JP7741254B2 - Video display device - Google Patents

Description

The present invention relates to a video display device and a video output device.

One of the extension features of digital broadcasting services is data broadcasting, which transmits digital data via broadcast waves and displays various information such as weather forecasts, news, and recommended programs. Many television receivers capable of receiving data broadcasting are already commercially available, and many technologies related to receiving data broadcasting have been published, including Patent Document 1 below.

Japanese Patent Application Laid-Open No. 2001-186486

In response to recent changes in the content distribution environment, television receivers are also being required to offer a variety of enhanced functionality. In particular, there is a strong demand for content and linked applications to be distributed over broadband networks such as the Internet, as well as for higher resolution and definition video content. However, it is difficult to provide high-value-added television receivers that can meet these demands by simply utilizing the data broadcasting reception functions and other features of current television receivers, or by simply expanding the functionality of said data broadcasting reception functions and other features.

The object of the present invention is to provide a video display device and a video output device that can perform functions with higher added value.

The technology described in the claims is used as a means to solve the above problem.

As an example, a video display device that displays video based on program content received via broadcast and/or communication includes a display unit capable of displaying video based on the program content and program information, a broadcast receiving unit capable of receiving program content via broadcast and transfer characteristic information related to the color gamut or luminance to which the program content corresponds, a communication unit capable of receiving program content via communication and transfer characteristic information related to the color gamut or luminance to which the program content corresponds, a storage unit that stores display characteristic information related to the color gamut or luminance that the display unit can handle, which displays video based on the program content received by the broadcast receiving unit and/or the communication unit, and a storage unit that stores display characteristic information related to the color gamut or luminance that the display unit can handle, and a storage unit that stores the transfer characteristic information received by the broadcast receiving unit and/or the communication unit. The video display device includes a video conversion processing unit that performs color gamut conversion processing or luminance conversion processing of the received program content based on the received information and the display characteristic information read from the storage unit, a speaker that outputs audio, and an IP interface, wherein the color gamut conversion processing in the video conversion processing unit is not performed if the color gamut indicated in the transfer characteristic information is contained within the color gamut indicated in the display characteristic information, and is performed if the color gamut indicated in the transfer characteristic information is not contained within the color gamut indicated in the display characteristic information, and the program information displayed on the display unit includes information indicating whether the program content received by the broadcast receiving unit and/or the communication unit is HDR video content based on the transfer characteristic information.

By using the technology of this invention, it is possible to provide video display devices and video output devices that can perform functions with higher added value.

1 is a system configuration diagram illustrating an example of a broadcast communication system including a broadcast receiving device according to a first embodiment. FIG. 1 is an explanatory diagram of an overview of a coded signal in MMT. FIG. 1 is a diagram illustrating the configuration of an MPU in MMT. FIG. 1 is a diagram illustrating the structure of an MMTP packet in MMT. FIG. 1 is a conceptual diagram of a protocol stack for a broadcasting system using MMT. FIG. 1 is a diagram showing a hierarchical structure of control information used in a broadcasting system. This is a list of tables used in the TLV-SI of the broadcasting system. This is a list of descriptors used in the TLV-SI of the broadcasting system. This is a list of messages used in MMT-SI of the broadcasting system. This is a list of tables used in MMT-SI of the broadcasting system. This is a list (part 1) of descriptors used in MMT-SI of the broadcasting system. This is a list (part 2) of descriptors used in MMT-SI of the broadcasting system. FIG. 2 is a diagram showing the relationship between data transmission in a broadcasting system and each table. 1 is a block diagram of a broadcast receiving device according to a first embodiment. FIG. 2 is a configuration diagram of a logical plane structure of a presentation function of the broadcast receiving device according to the first embodiment. 1 is a system configuration diagram of clock synchronization/presentation synchronization of a broadcast receiving device according to a first embodiment. FIG. 2 is a software configuration diagram of the broadcast receiving device according to the first embodiment. FIG. 2 is a block diagram of a broadcast station server according to the first embodiment. FIG. 2 is a block diagram of a service provider server according to the first embodiment. FIG. 1 is a block diagram of a portable information terminal according to a first embodiment. FIG. 2 is a software configuration diagram of the portable information terminal according to the first embodiment. A diagram showing the data structure of MH-TOT of the broadcasting system. FIG. 10 is a diagram illustrating the format of the JST_time parameter of a broadcasting system. 10 is a diagram showing a method for calculating the current date from the MJD of the broadcast receiving device according to the first embodiment. FIG. A diagram showing the configuration of the NTP format of a broadcasting system. A diagram showing the data structure of an MPU timestamp descriptor for a broadcasting system. A diagram showing the data structure of time information in the TMCC extension information area of a broadcasting system. 4 is an operational sequence diagram of the broadcast receiving device according to the first embodiment during channel scanning. FIG. A diagram showing the data structure of TLV-NIT of a broadcasting system. FIG. 10 is a diagram illustrating the data structure of a satellite distribution system descriptor for a broadcasting system. FIG. 10 is a diagram illustrating the data structure of a service list descriptor for a broadcasting system. FIG. 1 is a diagram showing the data structure of an AMT of a broadcasting system. 4 is a diagram illustrating an operation sequence when selecting a channel in the broadcast receiving device according to the first embodiment. FIG. A diagram showing the data structure of the MPT of the broadcasting system. A diagram showing the data structure of an LCT of a broadcasting system. FIG. 10 is a diagram illustrating an example of assignment of layouts to layout numbers based on an LCT. FIG. 10 is a diagram illustrating an example of assignment of layouts to layout numbers based on an LCT. FIG. 10 is a diagram illustrating an example of assignment of layouts to layout numbers based on an LCT. FIG. 10 is a diagram illustrating an example of assignment of layouts to layout numbers based on an LCT. 10A and 10B are diagrams illustrating the operation of exception handling in screen layout control based on LCT. 10A and 10B are diagrams illustrating the operation of exception handling in screen layout control based on LCT. A diagram showing the data structure of MH-EIT of a broadcasting system. FIG. 2 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 2 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 2 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. 3 is a diagram showing a screen display when an emergency alert broadcast is displayed on the broadcast receiving device according to the first embodiment. FIG. FIG. 10 is a block diagram of a broadcast receiving device according to a second embodiment. 10A and 10B are diagrams illustrating inconsistencies in the current time display when switching broadcast services. 10A and 10B are diagrams illustrating the operation of current time information reference source selection control according to the second embodiment. FIG. 10 is a screen display diagram of an EPG screen of a broadcast receiving device according to a second embodiment. FIG. 10 is a screen display diagram of an EPG screen of a broadcast receiving device according to a second embodiment. FIG. 10 is a system configuration diagram of a broadcast communication system according to a third embodiment. FIG. 10 is a diagram illustrating the data structure of a content information descriptor of a broadcasting system. FIG. 10 is a diagram illustrating the meaning of content types in a content information descriptor of a broadcasting system. 10 is a diagram illustrating the meaning of source device primary color chromaticity coordinates and source device white chromaticity coordinates in a content information descriptor of a broadcasting system. FIG. FIG. 10 is a diagram illustrating the meaning of EOTF identification in a content information descriptor of a broadcasting system. FIG. 11 is a screen display diagram of an EPG screen of a broadcast receiving device according to a third embodiment. FIG. 1 is a diagram illustrating a deviation in color gamut between a source device and a monitor device. 10A and 10B are diagrams illustrating a color gamut conversion process of a broadcast receiving device according to a third embodiment. 10A and 10B are diagrams illustrating a color gamut conversion process of a broadcast receiving device according to a third embodiment. FIG. 10 is a diagram illustrating image quality adjustment items of a broadcast receiving device according to a third embodiment. 10A and 10B are diagrams illustrating a luminance level conversion process of a broadcast receiving device according to a third embodiment. 10A and 10B are diagrams illustrating a luminance level conversion process of a broadcast receiving device according to a third embodiment. FIG. 10 is a system configuration diagram of a broadcast communication system according to a fourth embodiment. FIG. 10 is a block diagram of a broadcast receiving device according to a fourth embodiment. FIG. 10 is a software configuration diagram of a broadcast receiving device according to a fourth embodiment. FIG. 10 is a diagram illustrating an interface configuration between a broadcast receiving device and a monitor device according to a fourth embodiment. 10 is a diagram illustrating mastering information output by a broadcast receiving device according to a fourth embodiment. FIG.

Hereinafter, examples of embodiments of the present invention will be described with reference to the drawings.
Example 1

[System configuration]
1 is a system configuration diagram showing an example of a broadcast communication system including a broadcast receiving device of this embodiment. The broadcast communication system of this embodiment is composed of a broadcast receiving device 100 and an antenna 100a, a broadband network such as the Internet 200, a router device 200r and an access point 200a, a broadcast station radio tower 300t and a broadcast satellite (or communication satellite) 300s, a broadcast station server 300, a service provider server 400, other application servers 500, a mobile telephone communication server 600 and a base station 600b of a mobile telephone communication network, and a portable information terminal 700.

Broadcast receiving device 100 receives broadcast waves transmitted from radio tower 300t via broadcast satellite (or communication satellite) 300s and antenna 100a. Alternatively, broadcast waves transmitted from radio tower 300t may be received directly from antenna 100a without going through broadcast satellite (or communication satellite) 300s. Broadcast receiving device 100 can also connect to Internet 200 via router device 200r, enabling it to send and receive data via communication with various server devices and other communication devices on Internet 200.

The router device 200r is connected to the Internet 200 via wired communication, and is connected to the broadcast receiving device 100 via wired or wireless communication, and to the mobile information terminal 700 via wireless communication. The wireless communication may use a method such as Wi-Fi (registered trademark). This allows each server device and other communication device on the Internet 200 to transmit and receive data to and from the broadcast receiving device 100 and the mobile information terminal 700 via the router device 200r. Note that communication between the broadcast receiving device 100 and the mobile information terminal 700 may also be performed directly using a method such as Bluetooth (registered trademark) or NFC (Near Field Communication), without going through the router device 200r.

Radio tower 300t is the broadcasting equipment of the broadcasting station, and transmits broadcast waves containing encoded data for broadcast programs, subtitle information, other applications, general-purpose data, etc. Broadcast satellite (or communication satellite) 300s is a repeater that receives broadcast waves transmitted from the broadcasting station's radio tower 300t, performs appropriate frequency conversion, etc., and then retransmits the broadcast waves to antenna 100a connected to broadcast receiving device 100. The broadcasting station is also assumed to have a broadcasting station server 300. Broadcasting station server 300 stores broadcast programs (video content, etc.) and metadata for each broadcast program, such as the program title, program ID, program summary, cast information, and broadcast date and time, and is capable of providing the video content and each metadata to service providers based on a contract. The provision of the video content and each metadata to service providers may be performed via an API (Application Programming Interface) provided by broadcasting station server 300.

The service provider server 400 is a server device provided by a service provider, and is capable of providing various services linked to broadcast programs distributed by broadcast stations. The service provider server 400 also stores, manages, and distributes video content and metadata provided by the broadcast station server 300, as well as various content and applications linked to broadcast programs. It also has the function of searching for and providing a list of available content and applications in response to inquiries from television receivers, etc. The storage, management, and distribution of the content and metadata and the storage, management, and distribution of the applications may be performed by different server devices. The broadcast station and the service provider may be the same or different. Multiple service provider servers 400 may be provided for different services. The functions of the service provider server 400 may also be provided by the broadcast station server 300.

The other application servers 500 are well-known server devices that store, manage, and distribute other general applications, operating programs, content, data, etc. There may be multiple other application servers 500 on the Internet 200.

Mobile telephone communication server 600 is connected to the Internet 200, and is also connected to mobile information terminal 700 via base station 600b. Mobile telephone communication server 600 manages telephone communications (calls) and data transmission and reception via the mobile telephone communication network for mobile information terminal 700, enabling data transmission and reception between mobile information terminal 700 and various server devices and other communication devices on the Internet 200. Communication between base station 600b and mobile information terminal 700 may be performed using the W-CDMA (Wideband Code Division Multiple Access) (registered trademark) system, GSM (Global System for Mobile communications) (registered trademark) system, LTE (Long Term Evolution) system, or other communication systems.

The mobile information terminal 700 is assumed to have the functions of telephone communication (calls) and data transmission/reception via a mobile telephone communication network, as well as wireless communication functions such as Wi-Fi (registered trademark). The mobile information terminal 700 can connect to the Internet 200 via a router device 200r or an access point 200a, or via a base station 600b of the mobile telephone communication network and a mobile telephone communication server 600, and can transmit and receive data through communication with various server devices and other communication devices on the Internet 200. The access point 200a is connected to the Internet 200 via wired communication, and is connected to the mobile information terminal 700 via wireless communication. The wireless communication may use a method such as Wi-Fi (registered trademark). Note that communication between the mobile information terminal 700 and the broadcast receiving device 100 may be performed via the access point 200a, the Internet 200, and the router device 200r, or via the base station 600b, the mobile telephone communication server 600, the Internet 200, and the router device 200r.

[Overview of the MMT method]
1 is a television receiver that is compatible with MMT (MPEG Media Transport), instead of TS (Transport Stream) (hereinafter referred to as MPEG2-TS) defined in the MPEG (Moving Picture Experts Group)-2 system, which is widely used in conventional digital broadcasting systems as a media transport method for transmitting data such as video and audio. The television receiver may also be compatible with both MPEG2-TS and MMT.

MPEG2-TS is characterized by multiplexing the video, audio, and other components that make up a program into a single stream along with control signals and a clock. Because the clock is also treated as a single stream, it is suitable for transmitting a single piece of content over a single transmission path with guaranteed transmission quality, and has been adopted in many conventional digital broadcasting systems. However, in recent years, the diversification of content, the diversification of devices that use content, the diversification of transmission paths for delivering content, and the diversification of content storage environments have all led to limitations in the functionality of MPEG2-TS in response to changes in the content distribution environment. Therefore, a newly developed media transport method is MMT.

Figure 2A shows an example of an overview of an encoded signal in the MMT of this embodiment. As shown in the figure, the MMT of this embodiment has the following elements constituting the encoded signal: MFU (Media Fragment Unit), MPU (Media Processing Unit), MMTP (MMT Protocol) payload, and MMTP packet. The MFU is the format used when transmitting video, audio, etc., and may be configured in NAL (Network Abstraction Layer) units or access units. The MPU may be configured with MPU metadata containing information about the overall MPU configuration, movie fragment metadata containing information about the encoded media data, and sample data, which is the encoded media data. It is also assumed that the MFU can be extracted from the sample data. Furthermore, for media such as video components and audio components, presentation times and decoding times may be specified in MPU or access unit units. Figure 2B shows an example of the configuration of an MPU.

An MMTP packet consists of a header section and an MMTP payload, and transmits control information for the MFU and MMT. The MMTP payload has a payload header corresponding to the content (data unit) stored in the payload section. Figure 2C shows an example of an overview of how an MFU is constructed from video/audio signals, then stored in the MMTP payload to construct an MMTP packet. Note that for video signals encoded using inter-frame prediction, it is desirable to construct MPUs in GOP (Group of Pictures) units. Furthermore, if the size of the MFU to be transmitted is small, one MFU may be stored in one payload section, or multiple MFUs may be stored in one payload section. Furthermore, if the size of the MFU to be transmitted is large, one MFU may be divided and stored in multiple payload sections. In addition, MMTP packets may be protected using techniques such as AL-FEC (Application Layer Forward Error Correction) and ARQ (Automatic Repeat Request) to recover from packet loss on the transmission path.

In the broadcasting system of this embodiment, MPEG-H HEVC (High Efficiency Video Coding) is used as the video encoding method, and MPEG-4 AAC (Advanced Audio Coding) or MPEG-4 ALS (Audio Lossless Coding) is used as the audio encoding method. The encoded data of the video and audio of the broadcast program encoded using each of the above methods is in MFU or MPU format, and then loaded onto an MMTP payload for MMTP packetization and transmitted in IP (Internet Protocol) packets. Data content related to the broadcast program may also be in MFU or MPU format, and then loaded onto an MMTP payload for MMTP packetization and transmitted in IP packets. Four types of data content transmission methods will be available: a subtitle/superimposed text transmission method used for streaming data synchronized with broadcasting; an application transmission method used for transmitting data asynchronously with broadcasting; an event message transmission method used for synchronous/asynchronous message notifications to applications running on television receivers; and a general-purpose data transmission method for transmitting other general-purpose data synchronously/asynchronously.

To transmit MMTP packets, UDP/IP (User Datagram Protocol/Internet Protocol) is used on the broadcast transmission path, and UDP/IP or TCP/IP (Transmission Control Protocol/Internet Protocol) is used on the communication line. Furthermore, the TLV (Type Length Value) multiplexing method is used on the broadcast transmission path for efficient transmission of IP packets. An example of a protocol stack for the broadcast system of this embodiment is shown in Figure 3. In the figure, (A) is an example of a protocol stack on the broadcast transmission path, and (B) is an example of a protocol stack on the communication line.

The broadcasting system of this embodiment provides a mechanism for transmitting two types of control information: MMT-SI (MMT-Signaling Information) and TLV-SI (TLV-Signaling Information). MMT-SI is control information that indicates the configuration of a broadcast program, etc. It is formatted as an MMT control message, placed in an MMTP payload, packetized as an MMTP packet, and transmitted in an IP packet. TLV-SI is control information related to multiplexing of IP packets, and provides information for channel selection and information on the correspondence between IP addresses and services.

In addition, in broadcasting systems using MMT, time information is transmitted to provide absolute time. While MPEG2-TS indicates the display time of components based on a different clock for each TS, MMT indicates the display time of components based on Coordinated Universal Time (UTC). These mechanisms enable terminal devices to synchronize and display components transmitted from different transmission points over different transmission paths. To provide UTC, IP packets in NTP (Network Time Protocol) format are used.

[Control information for broadcasting systems using MMT]
As described above, the broadcast system compatible with the broadcast receiving device 100 of this embodiment provides the following control information: TLV-SI, which relates to the TLV multiplexing method for multiplexing IP packets, and MMT-SI, which relates to the MMT media transport method. TLV-SI provides information for the broadcast receiving device 100 to demultiplex IP packets multiplexed onto the broadcast transmission path. TLV-SI is composed of "tables" and "descriptors." Tables are transmitted in section format, and "descriptors" are placed within the "tables." MMT-SI is transmission control information that indicates the configuration of MMT packages and information related to broadcast services. MMT-SI is composed of three layers: "messages" that store "tables" and "descriptors,""tables" that contain elements and attributes indicating specific information, and "descriptors" that indicate more detailed information. An example of the hierarchical structure of control information used in the broadcasting system of this embodiment is shown in Figure 4.

<Tables used in TLV-SI>
5A shows a list of "tables" used in the TLV-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. In this embodiment, the following "tables" are used as TLV-SI "tables."

(1) TLV-NIT
The Network Information Table for TLV (TLV-NIT) represents information about the physical configuration of TLV streams transmitted by a network and the characteristics of the network itself.

(2) AMT
The Address Map Table (AMT) provides a list of multicast groups for the IP packets that make up each service transmitted in the network.

(3) Tables Set by Service Providers In addition, service providers and the like can prepare tables that they have set independently.

<Descriptors used in TLV-SI>
5B shows a list of "descriptors" placed in the TLV-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. In this embodiment, the following "descriptors" are used as TLV-SI "descriptors."

(1) Service List Descriptor The service list descriptor provides a list of services by service identification and service format type.

(2) Satellite Distribution System Descriptor The satellite distribution system descriptor indicates the physical conditions of the satellite transmission path.

(3) System Management Descriptor The system management descriptor is used to distinguish between broadcast and non-broadcast.

(4) Network Name Descriptor The network name descriptor describes the network name using character codes.

(5) Descriptors Set by Service Providers In addition, service providers and the like can prepare their own descriptors.

<Messages used in MMT-SI>
6A shows a list of "messages" used in MMT-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. In this embodiment, the following "messages" are used in MMT-SI.

(1) PA Message The Package Access (PA) message is used to transmit various tables.

(2) M2 Section Message The M2 section message is used to transmit the section extension format of the MPEG-2 Systems.

(3) CA Message The CA message is used to transmit a table for identifying the conditional access system.

(4) M2 Short Section Message The M2 short section message is used to transmit the section short format of the MPEG-2 Systems.

(5) Data Transmission Message A data transmission message is a message that stores a table related to data transmission.

(6) Messages set by service providers In addition, service providers and the like can prepare messages that they set independently.

<Tables used in MMT-SI>
FIG. 6B shows a list of "tables" used in MMT-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. A table is control information having elements and attributes indicating specific information, and is stored in a message and transmitted in an MMTP packet. Note that the message that stores the table may be determined depending on the table. In this embodiment, the following "tables" are used for MMT-SI.

(1) MPT
The MMT Package Table (MPT) provides information that configures a package, such as a list of assets and their locations on the network, etc. The MPT may be stored in a PA message.

(2) PLT
The package list table (PLT) indicates a list of IP data flows and packet IDs transmitting PA messages of MMT packages provided as broadcast services, and IP data flows transmitting IP services. The PLT may be stored in the PA message.

(3) LCT
A Layout Configuration Table (LCT) is used to associate layout information for presentation with a layout number, and may be stored in a PA message.

(4) ECM
An Entitlement Control Message (ECM) is common information consisting of program information and control information, and delivers key information for descrambling, etc. The ECM may be stored in an M2 section message.

(5) EMM
An Entitlement Management Message (EMM) transmits individual information including contract information for each subscriber, key information for decrypting ECM (common information), etc. The EMM may be stored in an M2 section message.

(6) CAT(MH)
The Conditional Access Table (CAT) (MH) is used to store a descriptor for identifying a conditional access system. The CAT (MH) may be stored in a CA message.

(7) DCM
The Download Control Message (DCM) transmits key-related information, such as a key for decrypting a transmission path encryption for downloading. The DCM may be stored in the M2 section message.

(8) DMM
The Download Management Message (DMM) transmits key-related information such as a download key for decrypting the DCM. The DMM may be stored in the M2 section message.

(9) MH-EIT
The MH-Event Information Table (MH-EIT) is time-series information about events included in each service. The MH-EIT may be stored in the M2 section message.

(10) MH-AIT
The MH-Application Information Table (MH-AIT) stores all information related to applications and the activation state required for the application, etc. The MH-AIT may be stored in the M2 section message.

(11) MH-BIT
The MH-Broadcaster Information Table (MH-BIT) is used to present information about broadcasters present on the network. The MH-BIT may be stored in the M2 section message.

(12) MH-SDTT
The MH-Software Download Trigger Table (MH-SDTT) is used for download notification information and may be stored in the M2 section message.

(13) MH-SDT
The MH-Service Description Table (MH-SDT) has sub-tables that represent services included in a specific TLV stream, and transmits information about the channel, such as the channel name, the broadcaster name, etc. The MH-SDT may be stored in the M2 section message.

(14) MH-TOT
The MH-Time Offset Table (MH-TOT) carries JST time and date (Modified Julian Date) information. The MH-TOT may be stored in the M2 short section message.

(15) MH-CDT
The MH-Common Data Table (MH-CDT) is used to transmit common data in section format to be stored in non-volatile memory for all receivers that receive it. The MH-CDT may be stored in an M2 section message.

(16) DDM Table The Data Directory Management Table (DDM table) provides a directory structure of files that constitute an application in order to separate the file structure of the application from the structure for file transmission. The DDM table may be stored in a data transmission message.

(17) DAM Table The Data Asset Management Table (DAM table) provides the configuration of the MPUs in the asset and version information for each MPU. The DAM table may be stored in a data transmission message.

(18) DCC Table The Data Content Configuration Table (DCC table) provides configuration information of files as data content to realize flexible and effective cache control. The DCC table may be stored in a data transmission message.

(19) EMT
The Event Message Table (EMT) is used to transmit information about event messages and may be stored in the M2 section message.

(20) Tables Set by Service Providers In addition, service providers and the like can prepare tables that they set independently.

<Descriptors used in MMT-SI>
6C and 6D show a list of "descriptors" arranged in the MMT-SI of the broadcasting system supported by the broadcast receiving device 100 of this embodiment. Descriptors are control information that provide more detailed information and are arranged in a table. Note that the table in which a descriptor is arranged may be determined depending on the descriptor. In this embodiment, the following "descriptors" are used in the MMT-SI.

(1) Asset Group Descriptor The asset group descriptor provides the group relationship of assets and the priority within the group. The asset group descriptor may be placed in the MPT.

(2) Event Package Descriptor The event package descriptor provides correspondence between an event representing a program and a package. The event package descriptor may be placed in the MH-EIT transmitted in the M2 section message.

(3) Background Color Specification Descriptor The background color specification descriptor provides the background color of the backmost element in the layout specification. The background color specification descriptor may be placed in the LCT.

(4) MPU Presentation Area Designation Descriptor The MPU presentation area designation descriptor provides the location where the MPU is to be presented. The MPU presentation area designation descriptor may be placed in the MPT.

(5) MPU Timestamp Descriptor The MPU Timestamp Descriptor indicates the presentation time of the first access unit in presentation order in the MPU. The MPU Timestamp Descriptor may be placed in the MPT.

(6) Dependency Descriptor The dependency descriptor provides the asset ID of the asset that is in dependency. The dependency descriptor may be placed in the MPT.

(7) Access Control Descriptor The access control descriptor provides information for identifying the conditional access method. The access control descriptor may be placed in the MPT or CAT (MH).

(8) Scrambling Method Descriptor The scrambling method descriptor provides information for identifying the encryption target and the type of encryption algorithm used during scrambling. The scrambling method descriptor may be placed in the MPT or CAT (MH).

(9) Message Authentication Scheme Descriptor The message authentication scheme descriptor provides information for identifying the message authentication scheme when performing message authentication. The message authentication scheme descriptor may be placed in the MPT or CAT(MH).

(10) Emergency Information Descriptor (MH)
The emergency information descriptor (MH) is used when an emergency alert is broadcast, and may be placed in the MPT.

(11) MH-MPEG-4 Audio Descriptor The MH-MPEG-4 Audio Descriptor is used to describe basic information for specifying the coding parameters of an audio stream of ISO/IEC 14496-3 (MPEG-4 Audio). The MH-MPEG-4 Audio Descriptor may be placed in the MPT.

(12) MH-MPEG-4 Audio Extension Descriptor The MH-MPEG-4 Audio Extension Descriptor is used to describe the profile and level of an MPEG-4 audio stream and settings specific to the encoding method. The MH-MPEG-4 Audio Extension Descriptor may be placed in the MPT.

(13) MH-HEVC Video Descriptor The MH-HEVC video descriptor is used to describe basic coding parameters of a video stream (HEVC stream) of ITU-T Recommendation H.265 | ISO/IEC 23008-2. The MH-HEVC video descriptor may be placed in the MPT.

(14) MH-Link Descriptor The MH-Link Descriptor identifies the service that will be provided if a viewer requests additional information related to a particular listing in the program service information system. The MH-Link Descriptor may be placed in the MPT, MH-EIT, MH-SDT, etc.

(15) MH-Event Group Descriptor The MH-Event Group Descriptor is used to indicate that multiple events are grouped when there is a relationship between them. The MH-Event Group Descriptor may be placed in the MH-EIT.

(16) MH-Service List Descriptor The MH-Service List Descriptor provides a list of services by service identification and service type. The MH-Service List Descriptor may be located in the MH-BIT.

(17) MH-Short Event Descriptor The MH-Short Event Descriptor represents the event name and a short description of the event in text form. The MH-Short Event Descriptor may be placed in the MH-EIT.

(18) MH-Extended Event Descriptor The MH-Extended Event Descriptor is used in addition to the MH-Short Event Descriptor to provide a detailed description of an event. The MH-Extended Event Descriptor may be placed in the MH-EIT.

(19) Video Component Descriptor The video component descriptor indicates parameters and descriptions related to a video component and is also used to express an elementary stream in text format. The video component descriptor may be placed in the MPT or MH-EIT.

(20) MH-Stream Identification Descriptor The MH-Stream Identification Descriptor is used to label a component stream of a service and to reference the description indicated by the video component descriptor in the MH-EIT using this label. The MH-Stream Identification Descriptor may be placed in the MPT.

(21) MH-Content Descriptor The MH-Content Descriptor indicates the genre of the event. The MH-Content Descriptor may be placed in the MH-EIT.

(22) MH-Parental Rating Descriptor The MH-Parental Rating Descriptor is used to indicate age-based viewing restrictions and to extend them to other restriction conditions. The MH-Parental Rating Descriptor may be placed in the MPT or the MH-EIT.

(23) MH-Audio Component Descriptor The MH-Audio Component Descriptor indicates each parameter of an audio elementary stream and is also used to express the elementary stream in text format. The MH-Audio Component Descriptor may be placed in the MPT or the MH-EIT.

(24) MH-Target Region Descriptor The MH-Target Region Descriptor is used to describe the region targeted by a program or some of the streams that make up a program. The MH-Target Region Descriptor may be placed in the MPT.

(25) MH-Series Descriptor The MH-Series Descriptor is used to identify a series of programs. The MH-Series Descriptor may be placed in the MH-EIT.

(26) MH-SI Transmission Parameter Descriptor The MH-SI transmission parameter descriptor is used to indicate the transmission parameters of the SI. The MH-SI transmission parameter descriptor may be placed in the MH-BIT.

(27) MH-Broadcaster Name Descriptor The MH-Broadcaster Name Descriptor describes the name of the broadcaster. The MH-Broadcaster Name Descriptor may be placed in the MH-BIT.

(28) MH-Service Descriptor The MH-Service Descriptor represents the name of the channel and its operator together with the service format type in character codes. The MH-Service Descriptor may be placed in the MH-SDT.

(29) IP Data Flow Descriptor The IP Data Flow Descriptor provides information about the IP data flows that constitute a service. The IP Data Flow Descriptor may be located in the MH-SDT.

(30) MH-CA Activation Descriptor The MH-CA activation descriptor describes activation information for activating a CAS program on the CAS platform. The MH-CA activation descriptor may be located in the MPT or CAT (CA).

(31) MH-Type Descriptor The MH-Type descriptor indicates the type of file transmitted in the application transmission method. The MH-Type descriptor may be placed in the DAM table.

(32) MH-Info Descriptor The MH-Info descriptor describes information about an MPU or an item. The MH-Info descriptor may be placed in a DAM table.

(33) MH-Expire Descriptor The MH-Expire descriptor describes the expiration date of an item. The MH-Expire descriptor may be placed in the DAM table.

(34) MH-Compression Type Descriptor The MH-Compression Type Descriptor indicates that the item to be transmitted is compressed, and indicates the compression algorithm and the number of bytes of the item before compression. The MH-Compression Type Descriptor may be placed in the DAM table.

(35) MH-Data Coding Scheme Descriptor The MH-Data Coding Scheme Descriptor is used to identify a data coding scheme. The MH-Data Coding Scheme Descriptor may be placed in the MPT.

(36) UTC-NPT Reference Descriptor The UTC-NPT reference descriptor is used to convey the relationship between the NPT (Normal Play Time) and the UTC. The UTC-NPT reference descriptor may be placed in the EMT.

(37) Event Message Descriptor The event message descriptor conveys information about event messages in general. The event message descriptor may be placed in the EMT.

(38) MH-Local Time Offset Descriptor The MH-Local Time Offset Descriptor is used when daylight saving time is in effect, to assign a certain offset value to the actual time (e.g., UTC + 9 hours) and the displayed time for the human system. The MH-Local Time Offset Descriptor may be placed in the MH-TOT.

(39) MH-Component Group Descriptor The MH-Component Group Descriptor defines and identifies a combination of components within an event. The MH-Component Group Descriptor may be placed in the MH-EIT.

(40) MH-Logo Transmission Descriptor The MH-Logo Transmission Descriptor is used to describe a simple logo character string, pointing to a logo in CDT format, etc. The MH-Logo Transmission Descriptor may be placed in the MH-SDT.

(41) MPU Extended Timestamp Descriptor The MPU extended timestamp descriptor provides the decoding time of an access unit in an MPU. The MPU extended timestamp descriptor may be placed in the MPT.

(42) MPU Download Content Descriptor The MPU download content descriptor is used to describe attribute information of content downloaded using an MPU. The MPU download content descriptor may be placed in the MH-SDTT.

(43) MH-Network Download Content Descriptor The MH-Network Download Content Descriptor is used to describe attribute information of content downloaded using a network. The MH-Network Download Content Descriptor may be placed in the MH-SDTT.

(44) MH-Application Descriptor The MH-Application Descriptor describes information about an application. The MH-Application Descriptor may be placed in the MH-AIT.

(45) MH-Transmission Protocol Descriptor The MH-Transmission Protocol Descriptor is used to specify a transmission protocol such as broadcasting or communication and to indicate location information of an application that depends on the transmission protocol. The MH-Transmission Protocol Descriptor may be placed in the MH-AIT.

(46) MH-Simple Application Location Descriptor The MH-Simple Application Location Descriptor is written to indicate details of where to obtain an application. The MH-Simple Application Location Descriptor may be placed in the MH-AIT.

(47) MH-Application Boundary Authority Setting Descriptor The MH-Application Boundary Authority Setting Descriptor is used to set an application boundary and to set broadcast resource access authority for each area (URL). The MH-Application Boundary Authority Setting Descriptor may be placed in the MH-AIT.

(48) MH-Launch Priority Information Descriptor The MH-Launch Priority Information Descriptor is written to specify the launch priority of an application. The MH-Launch Priority Information Descriptor may be placed in the MH-AIT.

(49) MH-Cache Information Descriptor The MH-Cache Information Descriptor is written to be used for cache control when the resources constituting an application are cached and stored when the application is expected to be reused. The MH-Cache Information Descriptor may be placed in the MH-AIT.

(50) MH-Probabilistic Application Delay Descriptor The MH-Probabilistic Application Delay Descriptor is used to delay the timing of application control by a probabilistically set delay amount, assuming load balancing of server access for application acquisition. The MH-Probabilistic Application Delay Descriptor may be placed in the MH-AIT.

(51) Link Destination PU Descriptor The link destination PU descriptor describes other presentation units that may transition from the presentation unit (PU). The link destination PU descriptor may be placed in the DCC table.

(52) Lock Cache Designation Descriptor The lock cache designation descriptor describes the designation of a file to be cached and locked in the presentation unit. The lock cache designation descriptor may be placed in the DCC table.

(53) Unlock Cache Designation Descriptor The unlock cache designation descriptor describes the designation of a file to be unlocked among the files locked in the presentation unit. The unlock cache designation descriptor may be placed in the DCC table.

(54) Descriptors Set by Service Providers In addition, service providers and the like can prepare their own descriptors.

<Relationship between data transmission and each control information in the MMT system>
Here, the relationship between data transmission and representative tables in the broadcasting system supported by the broadcasting receiving device 100 of this embodiment will be described with reference to FIG. 6E.

In the broadcasting system supported by the broadcast receiving device 100 of this embodiment, data can be transmitted via multiple routes, such as a TLV stream via a broadcast transmission path and an IP data flow via a communication line. A TLV stream contains TLV-SI such as TLV-NIT and AMT, and an IP data flow, which is a data flow of IP packets. An IP data flow contains video assets containing a series of video MPUs and audio assets containing a series of audio MPUs. Similarly, an IP data flow may contain subtitle assets containing a series of subtitle MPUs, superimpose assets containing a series of superimpose MPUs, data assets containing a series of data MPUs, etc. These various assets are associated in units called "packages" by the MPT (MMT Package Table), which is stored in and transmitted in a PA message. Specifically, the association is achieved by listing in the MPT the package ID (corresponding to the "MMT_package_id_byte" parameter shown in Figure 17, which will be described later) and the asset IDs of each asset included in the package (corresponding to the "asset_id_byte" parameter shown in Figure 17, which will be described later).

The assets constituting the package can be only assets in the TLV stream, but as shown in Figure 6E, it is also possible to include assets transmitted via the IP data flow of the communication line. This can be achieved by including location information of each asset included in the package (corresponding to "MMT_general_location_info()" shown in Figure 17 described later) in the MPT, allowing the broadcast receiving device 100 of this embodiment to grasp the reference destination of each asset. Specifically, by changing the value of the "MMT_general_location_infolocation_type" parameter placed in the location information,
(1) Data multiplexed in the same IP data flow as the MPT (location_type = 0x00)
(2) Data multiplexed in IPv4 data flow (location_type = 0x01)
(3) Data multiplexed in IPv6 data flow (location_type = 0x02)
(4) Data multiplexed into the broadcast MPEG2-TS (location_type = 0x03)
(5) Data multiplexed in IP data flow in MPEG2-TS format (location_type = 0x04)
(6) Data at the specified URL (location_type = 0x05)
It is possible to configure the broadcast receiving device 100 so that it can refer to various types of data transmitted via various transmission paths, such as the above.

Of the above-mentioned references, (1) is, for example, an IP data flow received via a digital broadcast signal received by the tuner/demodulator unit 131 of the broadcast receiving device 100 in Figure 7A, which will be described later. When the MPT is also transmitted as part of the IP data flow on the communication line side, the reference of (1) may be an IP data flow received via the communication line by the LAN communication unit 121, which will be described later. Furthermore, (2), (3), (5), and (6) above are IP data flows received via the communication line by the LAN communication unit 121, which will be described later. Furthermore, (4) above can be used, for example, in the case of a broadcast receiving device that has both a receiving function for receiving digital broadcast signals using the MMT system and a receiving function for receiving digital broadcast signals using the MPEG2-TS system, such as the broadcast receiving device 800 of Example 2 shown in Figure 24 described below, to refer to data multiplexed into MPEG2-TS received by the receiving function for receiving digital broadcast signals using the MPEG2-TS system, based on the MPT location information ('MMT_general_location_info()') included in the digital broadcast signals using the MMT system.

Note that while the data that makes up a "package" is specified in this way, in the broadcasting system that the broadcast receiving device 100 of this embodiment supports, the series of data in that "package" unit is treated as a digital broadcast "service" unit.

Furthermore, the MPT contains presentation time information for each MPU specified by the MPT (corresponding to the "mpu_presentation_time" parameter shown in Figure 13B, described below). Using this presentation time information, multiple MPUs specified by the MPT can be presented (displayed, output, etc.) in a coordinated manner based on a clock based on NTP, which is time information in UTC notation. Controlling the presentation of various data using this NTP-based clock will be described later.

The data transmission method of this embodiment shown in Figure 6E also includes the concept of an "event." An "event" is a concept that indicates a so-called "program" handled by the MH-EIT sent in an M2 section message. Specifically, in a "package" indicated by an event package descriptor stored in the MH-EIT, the data included in the concept of the "event" is a series of data included in a period from the start time stored in the MH-EIT (corresponding to the "start_time" parameter shown in Figure 21 below) to the duration (corresponding to the "duration" parameter shown in Figure 21 below). The MH-EIT can be used in the broadcast receiving device 100 of this embodiment for various processes on an "event" basis (for example, generating a program guide, controlling recording and viewing reservations, and copyright management processes such as temporary storage).

[Hardware configuration of broadcast receiving device]
7A is a block diagram showing an example of the internal configuration of broadcast receiving device 100. Broadcast receiving device 100 is composed of a main control unit 101, a system bus 102, a ROM 103, a RAM 104, a storage (accumulation) unit 110, a LAN communication unit 121, an extension interface unit 124, a digital interface unit 125, a tuner/demodulation unit 131, a separation unit 132, a video decoder 141, a video color gamut conversion unit 142, an audio decoder 143, a superimposed character decoder 144, a subtitle decoder 145, a subtitle synthesis unit 146, a subtitle color gamut conversion unit 147, a data decoder 151, a cache unit 152, an application control unit 153, a browser unit 154, an application color gamut conversion unit 155, a sound source unit 156, a video synthesis unit 161, a monitor unit 162, a video output unit 163, an audio synthesis unit 164, a speaker unit 165, an audio output unit 166, and an operation input unit 170.

The main control unit 101 is a microprocessor unit that controls the entire broadcast receiving device 100 in accordance with a predetermined operating program. The system bus 102 is a data communication path for transmitting and receiving data between the main control unit 101 and each operating block within the broadcast receiving device 100.

ROM (Read Only Memory) 103 is a non-volatile memory that stores basic operating programs such as an operating system and other operating programs. For example, a rewritable ROM such as an EEPROM (Electrically Erasable Programmable ROM) or flash ROM is used. ROM 103 may also store operational setting values required for the operation of broadcast receiving device 100. RAM (Random Access Memory) 104 serves as a work area when the basic operating programs and other operating programs are executed. ROM 103 and RAM 104 may be integrated with main control unit 101. ROM 103 may also use a portion of the storage area within storage unit 110, rather than being an independent configuration as shown in Figure 7A.

The storage (accumulation) unit 110 stores the broadcast receiving device 100's operating programs, operating setting values, personal information of the user of the broadcast receiving device 100, etc. It can also store operating programs downloaded via the Internet 200 and various data created by the operating programs. It can also store content such as video, still images, and audio obtained from broadcast waves or downloaded via the Internet 200. A portion of the storage (accumulation) unit 110 may replace all or part of the functions of the ROM 103. Furthermore, the storage (accumulation) unit 110 needs to retain the stored information even when external power is not being supplied to the broadcast receiving device 100. Therefore, devices such as non-volatile semiconductor element memory such as flash ROM or SSD (Solid State Drive), or magnetic disk drives such as HDD (Hard Disc Drive) are used.

The operating programs stored in the ROM 103 and storage unit 110 can be added to, updated, and have their functions expanded by downloading them from server devices on the Internet 200.

The LAN (Local Area Network) communication unit 121 is connected to the Internet 200 via the router device 200r, and transmits and receives data to and from each server device and other communication devices on the Internet 200. It also acquires the MMT data string (or a portion thereof) of a program transmitted via a communication line. The connection to the router device 200r may be wired or wireless, such as via Wi-Fi (registered trademark). The LAN communication unit 121 includes an encoding circuit, a decoding circuit, etc. The broadcast receiving device 100 may also include other communication units, such as a Bluetooth (registered trademark) communication unit, an NFC communication unit, or an infrared communication unit.

The tuner/demodulator 131 receives broadcast waves transmitted from the radio tower 300t via the antenna 100a and tunes (selects) to the channel of the service desired by the user under the control of the main controller 101. Furthermore, the tuner/demodulator 131 demodulates the received broadcast signal to obtain an MMT data sequence. Note that while the example shown in Figure 7A illustrates a configuration with one tuner/demodulator, the broadcast receiving device 100 may also be configured to include multiple tuner/demodulators for purposes such as simultaneous display on multiple screens or recording of other programs.

The separation unit 132 is an MMT decoder that distributes real-time presentation elements, such as video data sequences, audio data sequences, superimposed text data sequences, and subtitle data sequences, to the video decoder 141, audio decoder 143, superimposed text data sequence, and subtitle decoder 145, respectively, based on control signals in the input MMT data sequences. The data input to the separation unit 132 may be an MMT data sequence transmitted via a broadcast transmission path and demodulated by the tuner/demodulation unit 131, or an MMT data sequence transmitted via a communication line and received by the LAN communication unit 121. The separation unit 132 also plays multimedia applications and their component file data, temporarily storing them in the cache unit 152. The separation unit 132 also extracts general-purpose data and outputs it to the data decoder 151 for use in streaming data for players or applications that present data other than video, audio, and subtitles. Additionally, the separation unit 132 may perform error correction and access restriction control on the input MMT data sequence based on control from the main control unit 101.

The video decoder 141 decodes the video data stream input from the separation unit 132 and outputs video information. The video color gamut conversion unit 142 performs color space conversion processing on the video information decoded by the video decoder 141 as necessary for video synthesis processing in the video synthesis unit 161. The audio decoder 143 decodes the audio data stream input from the separation unit 132 and outputs the audio information. Streaming data in MPEG-DASH (MPEG-Dynamic Adaptive Streaming over HTTP) format, for example, acquired from the Internet 200 via the LAN communication unit 121 may also be input to the video decoder 141 and audio decoder 143. A plurality of video decoders 141, video color gamut conversion units 142, audio decoders 143, etc. may be provided to simultaneously decode multiple types of video data streams and audio data streams.

The superimposed text decoder 144 decodes the superimposed text data string input from the separation unit 132 and outputs superimposed text information. The subtitle decoder 145 decodes the subtitle data string input from the separation unit 132 and outputs subtitle information. The superimposed text information output from the superimposed text decoder 144 and the subtitle information output from the subtitle decoder 145 are combined in the subtitle composition unit 146, and furthermore, the subtitle color gamut conversion unit 147 performs color space conversion processing as necessary for the video composition processing in the video composition unit 161. Note that in this embodiment, of the services centered on text information presented simultaneously with the video of a broadcast program, those related to the content of the video are referred to as subtitles, and other services are referred to as superimposed text. Furthermore, when there is no need to distinguish between them, they will be collectively referred to as subtitles.

The browser unit 154 presents multimedia application files and their constituent file data obtained from a server device on the Internet 200 via the cache unit 152 or the LAN communication unit 121 in accordance with instructions from the application control unit 153, which interprets control information contained in the MMT data string and control information obtained from the server device on the Internet 200 via the LAN communication unit 121. The multimedia application files may be HTML (Hyper Text Markup Language) documents, BML (Broadcast Markup Language) documents, etc. The application information output from the browser unit 154 is further subjected to color space conversion processing as necessary in the application color gamut conversion unit 155 for video synthesis processing in the video synthesis unit 161. The browser unit 154 also plays application audio information by influencing the sound source unit 156.

The video synthesis unit 161 inputs the video information output from the video color gamut conversion unit 142, the subtitle information output from the subtitle color gamut conversion unit 147, the application information output from the application color gamut conversion unit 155, etc., and performs processing such as selection and/or superimposition as appropriate. The video synthesis unit 161 is equipped with a video RAM (not shown), and the monitor unit 162, etc. are driven based on the video information, etc. input to the video RAM. Furthermore, under the control of the main control unit 101, the video synthesis unit 161 performs scaling processing and superimposition processing of EPG (Electronic Program Guide) screen information created based on information such as the MH-EIT included in the MMT-SI, as necessary. The monitor unit 162 is a display device such as an LCD panel, and provides the video information selected and/or superimposed by the video synthesis unit 161 to the user of the broadcast receiving device 100. The video output unit 163 is a video output interface that outputs the video information that has been selected and/or superimposed by the video synthesis unit 161.

The presentation function of the broadcast receiving device 100 in this embodiment is equipped with a logical plane structure to display multimedia services as intended by the provider. Figure 7B shows an example of the configuration of the logical plane structure equipped with the presentation function of the broadcast receiving device 100 in this embodiment. In this logical plane structure, a text caption plane for displaying text captions is placed in the foreground, and a subtitle plane for displaying subtitles is placed in the next layer. A multimedia plane for displaying broadcast video, multimedia applications, or composite video thereof is placed in the third layer, and a background plane is placed in the background. The subtitle synthesis unit 146 and the video synthesis unit 161 draw text caption information on the text caption plane, subtitle information on the subtitle plane, and video information, application information, etc. on the multimedia plane. In addition, a background color is drawn on the background plane based on the LCT, etc. included in the MMT-SI. It is possible to prepare multiple third-layer multimedia planes depending on the number of video decoders 141. However, even if there are multiple multimedia planes, application information, etc. output from the application color gamut conversion unit 155 is output only to the foreground multimedia plane.

The audio synthesis unit 164 inputs the audio information output from the audio decoder 143 and the application audio information played by the sound source unit 156, and performs processing such as selection and/or mixing as appropriate. The speaker unit 165 provides the audio information selected and/or mixed by the audio synthesis unit 164 to the user of the broadcast receiving device 100. The audio output unit 166 is an audio output interface that outputs the audio information selected and/or mixed by the audio synthesis unit 164.

The expansion interface unit 124 is a group of interfaces for expanding the functionality of the broadcast receiving device 100, and in this embodiment is composed of an analog video/audio interface, a USB (Universal Serial Bus) interface, a memory interface, etc. The analog video/audio interface inputs analog video/audio signals from external video/audio output devices, outputs analog video/audio signals to external video/audio input devices, etc. The USB interface connects to a PC or the like to send and receive data. A HDD may be connected to record broadcast programs and content. A keyboard or other USB device may also be connected. The memory interface connects to a memory card or other memory medium to send and receive data.

The digital interface unit 125 is an interface that outputs or inputs encoded digital video data and/or digital audio data. The digital interface unit 125 is capable of directly outputting an MMT data sequence obtained by demodulation in the tuner/demodulation unit 131, an MMT data sequence obtained via the LAN communication unit 121, or mixed data of the above MMT data sequences. It may also be possible to control the MMT data sequence input from the digital interface unit 125 to be input to the separation unit 132. Digital content stored in the storage unit 110 may be output or stored in the storage unit 110 via the digital interface unit 125.

The digital interface unit 125 may be a DVI terminal, HDMI (registered trademark) terminal, DisplayPort (registered trademark) terminal, etc., which outputs or inputs data in a format conforming to the DVI specification, HDMI specification, DisplayPort specification, etc. It may also output or input data in a serial data format conforming to the IEEE 1394 specification, etc. It may also be configured as an IP interface that outputs digital interface data via hardware such as Ethernet (registered trademark) or wireless LAN. In this case, the digital interface unit 125 and the LAN communication unit 121 may share the same hardware configuration.

The operation input unit 170 is an instruction input unit that inputs operation instructions to the broadcast receiving device 100, and in this embodiment is configured with a remote control receiving unit that receives commands transmitted from a remote control (not shown) and an operation key with an array of button switches. Only one of these may be provided. The operation input unit 170 may also be replaced by a touch panel placed on top of the monitor unit 162. It may also be replaced by a keyboard or the like connected to the extended interface unit 124. The remote control (not shown) may also be replaced by a mobile information terminal 700 equipped with a remote control command transmission function.

As mentioned above, if the broadcast receiving device 100 is a television receiver or the like, the video output unit 163 and the audio output unit 166 are not essential components of the present invention. Furthermore, the broadcast receiving device 100 may be a television receiver, an optical disc drive recorder such as a DVD (Digital Versatile Disc) recorder, a magnetic disc drive recorder such as an HDD recorder, an STB (Set Top Box), etc. It may also be a PC (Personal Computer), tablet terminal, navigation device, game console, etc. equipped with digital broadcast reception function and broadcast communication linkage function. If the broadcast receiving device 100 is a DVD recorder, HDD recorder, STB, etc., the monitor unit 162 and speaker unit 165 may not be included. By connecting an external monitor and external speakers to the video output unit 163 and audio output unit 166 or the digital interface unit 125, it becomes possible to operate in the same way as the broadcast receiving device 100 of this embodiment.

[System configuration of clock synchronization/presentation synchronization of broadcast receiving device]
FIG. 7C shows an example of a system configuration for clock synchronization/presentation synchronization in a broadcasting system compatible with the broadcast receiving device 100 of this embodiment. In this broadcasting system, UTC is transmitted from the broadcast transmission system to the receiver (such as the broadcast receiving device 100 of this embodiment) in a 64-bit NTP timestamp format. In this NTP timestamp format, UTC "seconds or more" are represented by 32 bits, and "less than a second" is represented by 32 bits. However, in practice, it is difficult to reproduce one second with 32-bit precision. For this reason, a system clock for synchronizing a video system or for operating an NTP-formatted clock may have a frequency of, for example, 2 to the 24th power (approximately 16.8 MHz), as shown in the figure. Considering that the system clock in conventional broadcasting systems was 27 MHz and the ease of constructing receiver hardware, it is desirable to use a frequency that is a power of 2, such as 2 to the 28th power, as the system clock.

Note that if the system clock on the broadcast transmission system or receiver side is set to a frequency that is a power of 2, such as 2 to the 24th power to 2 to the 28th power, as described above, the lowest 8 to 4 bits of the NTP timestamp format transmitted from the broadcast transmission system to the receiver side, which are not referenced by the PLL (Phase Locked Loop) system used to reproduce the system clock or NTP format clock, may be fixed to 0 or 1. In other words, if the system clock is 2 to the nth power Hz (n = 24 in the example of Figure 7C), the lowest 32-n bits of the NTP timestamp format may be fixed to 0 or 1. Alternatively, the receiver side may process the lowest 32-n bits of the NTP timestamp format to be ignored.

When the broadcast transmission system receives NTP-formatted time information from an external source, it configures a PLL system with a 32+n-bit counter using a 2n-power Hz VCO (Voltage Controlled Oscillator), creating a transmission system clock that synchronizes with the externally provided time information. The entire signal processing system also operates in synchronization with the 2n-power Hz system clock. Furthermore, the output of the transmission system clock is periodically transmitted to the receiver via the broadcast transmission path as NTP-long formatted time information.

On the receiver side, time information in NTP long format is received via the broadcast transmission path, and, like the broadcast transmission system side, the receiving system clock is regenerated using a PLL system based on a 2n-power Hz VCO. This makes the receiving system clock synchronized with the broadcast transmission system side. Furthermore, by operating the receiver's signal processing system in synchronization with the 2n-power Hz system clock, clock synchronization is achieved between the broadcast transmission system side and the receiver side, enabling stable signal playback. Furthermore, the decoding time and presentation time for each presentation unit of the video/audio signal are set on the broadcast transmission system side based on the NTP format time information. Here, the MPT stored in the PA message transmitted in the broadcast signal contains the MPU timestamp descriptor shown in Figure 13B, described below. The "mpu_sequence_number" parameter in the MPU timestamp descriptor in Figure 13B indicates the sequence number of the MPU describing the timestamp, and the "mpu_presentation_time" parameter indicates the presentation time of the MPU in 64-bit NTP timestamp format. Therefore, the receiver can reference the MPU timestamp descriptor stored in the MPT to control the presentation (display, output, etc.) timing for each MPU of video signals, audio signals, subtitles, superimposed text, etc.

Note that when focusing on the control of the decoding timing and presentation timing for each presentation unit of the aforementioned video/audio signals, synchronization of the video/audio signals can be ensured even with a clock of about 2 to the power of 16 Hz (approximately 65.5 kHz), and in this case, it is not necessary to refer to the lower 16 bits of the NTP timestamp format described in the MPU timestamp descriptor, etc. In other words, if a 2 to the power of m Hz clock generated by dividing the system clock, etc., is used to control the decoding timing and presentation timing, it is not necessary to refer to the lower 32-m bits of the NTP timestamp format described in the MPU timestamp descriptor, etc. Therefore, the lower 32-m bits of the NTP timestamp format described in the MPU timestamp descriptor, etc. may be fixed to 0 or 1.

[Software configuration of broadcast receiving device]
7D is a software configuration diagram of the broadcast receiving device 100 of this embodiment, showing the software configuration in the ROM 103, RAM 104, and storage (accumulation) unit 110. In this embodiment, a basic operation program 1001 and other operation programs are stored in the ROM 103, and a receiving function program 1002 and other operation programs are stored in the storage (accumulation) unit 110. The storage (accumulation) unit 110 is also assumed to include a content storage area 1200 for storing content such as moving images, still images, and audio, an authentication information storage area 1300 for storing authentication information and the like required when accessing external mobile terminal devices and each server device, and various information storage areas for storing various other information.

The basic operation program 1001 stored in ROM 103 is loaded into RAM 104, and the main control unit 101 executes the loaded basic operation program to form a basic operation execution unit 1101. Similarly, the reception function program 1002 stored in the storage unit 110 is loaded into RAM 104, and the main control unit 101 executes the loaded reception function program to form a reception function execution unit 1102. Furthermore, RAM 104 is provided with a temporary storage area for temporarily storing data created when each operation program is executed, as needed.

In the following, for simplicity's sake, the process of the main control unit 101 expanding the basic operation program 1001 stored in ROM 103 into RAM 104 and executing it to control each operation block will be described as the basic operation execution unit 1101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The receiving function execution unit 1102 controls each operating block of the broadcast receiving device 100 to play components such as video and audio transmitted by the broadcasting system of this embodiment. In particular, the transport processing unit 1102a primarily controls the MMT decoder function of the separation unit 132, and distributes the video data streams, audio data streams, etc. separated from the MMT data stream to the corresponding decoding processing units. The AV decoding processing unit 1102b primarily controls the video decoder 141, audio decoder 143, etc. The application processing unit 1102c primarily controls the cache unit 152, application control unit 153, browser unit 154, and sound source unit 156. The character superimposition processing unit 1102d primarily controls the character superimposition decoder 144. The subtitle processing unit 1102e primarily controls the subtitle decoder 145. The general-purpose data processing unit 1102f primarily controls the data decoder 151. The EPG generation unit 1102g interprets the description contents of the MH-EIT and other information included in the MMT-SI to generate an EPG screen. The presentation processing unit 1102h mainly controls the video color gamut conversion unit 142, subtitle synthesis unit 146, subtitle color gamut conversion unit 147, application color gamut conversion unit 155, video synthesis unit 161, and audio synthesis unit 164 based on the logical plane structure.

The operating programs may be stored in advance in the ROM 103 and/or storage unit 110 at the time of product shipment. After product shipment, they may be acquired via the LAN communication unit 121 from another application server 500 or the like on the Internet 200. Furthermore, the operating programs may be stored on a memory card, optical disc, or the like and acquired via the expansion interface unit 124, etc.

[Configuration of broadcast station server]
8 is a block diagram showing an example of the internal configuration of the broadcast station server 300. The broadcast station server 300 is made up of a main control unit 301, a system bus 302, a RAM 304, a storage unit 310, a LAN communication unit 321, and a digital broadcast signal transmission unit 360.

The main control unit 301 is a microprocessor unit that controls the entire broadcast station server 300 in accordance with a predetermined operation program. The system bus 302 is a data communication path for transmitting and receiving data between the main control unit 301 and each operation block within the broadcast station server 300. The RAM 304 serves as a work area when each operation program is executed.

The storage unit 310 stores a basic operation program 3001, a broadcast content management/distribution program 3002, and a broadcast content transmission program 3003, and further includes a broadcast content storage area 3200 and a metadata storage area 3300. The broadcast content storage area 3200 stores program content for each broadcast program broadcast by a broadcast station. The metadata storage area 3300 stores metadata for each broadcast program, such as the program title, program ID, program summary, cast, broadcast date and time, and copy control information related to each program content.

In addition, the basic operation program 3001, broadcast content management/distribution program 3002, and broadcast content sending program 3003 stored in the storage unit 310 are each expanded into RAM 304, and the main control unit 301 executes each of the expanded programs to form a basic operation execution unit 3101, a broadcast content management/distribution execution unit 3102, and a broadcast content sending execution unit 3103.

In the following, for simplicity's sake, the process of the main control unit 301 expanding the basic operation program 3001 stored in the storage unit 310 into RAM 304 and executing it to control each operation block will be described as the basic operation execution unit 3101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The broadcast content management/distribution execution unit 3102 manages the program content and metadata of each broadcast program stored in the broadcast content storage area 3200 and the metadata storage area 3300, and controls the provision of the program content and metadata of each broadcast program to the service provider based on a contract. Furthermore, when providing the program content and metadata of each broadcast program to the service provider, the broadcast content management/distribution execution unit 3102 may, as necessary, perform authentication processing of the service provider server 400 based on the contract.

The broadcast content transmission execution unit 3103 performs time schedule management when transmitting MMT data sequences containing program content of broadcast programs stored in the broadcast content storage area 3200 and program titles, program IDs, and copy control information for program content of broadcast programs stored in the metadata storage area 3300 from the radio tower 300t via the digital broadcast signal transmission unit 360.

LAN communication unit 321 is connected to Internet 200 and communicates with service provider server 400 and the like on Internet 200. LAN communication unit 321 is equipped with an encoding circuit, a decoding circuit, and the like. Digital broadcast signal transmission unit 360 modulates MMT data strings composed of video data strings, audio data strings, program information data strings, etc., of program content of each broadcast program stored in broadcast content storage area 3200, and transmits them as digital broadcast waves via radio tower 300t.

[Configuration of service provider server]
9 is a block diagram showing an example of the internal configuration of the service provider server 400. The service provider server 400 is made up of a main control unit 401, a system bus 402, a RAM 404, a storage unit 410, and a LAN communication unit 421.

The main control unit 401 is a microprocessor unit that controls the entire service provider server 400 in accordance with a predetermined operating program. The system bus 402 is a data communication path for sending and receiving data between the main control unit 401 and each operating block within the service provider server 400. The RAM 404 serves as a work area when each operating program is executed.

The storage unit 410 stores a basic operation program 4001, a video content management/distribution program 4002, and an application management/distribution program 4004, and further includes a video content storage area 4200, a metadata storage area 4300, an application storage area 4400, and a user information storage area 4500. The video content storage area 4200 stores program content of broadcast programs provided by the broadcast station server 300 as video content. It also stores video content, etc. produced by the service provider. The metadata storage area 4300 stores various metadata provided by the broadcast station server 300 and metadata related to video content produced by the service provider. The application storage area 4400 stores various applications, etc. for realizing services linked to broadcast programs, which are distributed in response to requests from each television receiver. The user information storage area 4500 stores information (personal information, authentication information, etc.) related to users who are authorized to access the service provider server 400.

In addition, the basic operation program 4001, video content management/distribution program 4002, and application management/distribution program 4004 stored in the storage unit 410 are each expanded into RAM 404, and the main control unit 401 executes the expanded basic operation program, video content management/distribution program, and application management/distribution program to form a basic operation execution unit 4101, a video content management/distribution execution unit 4102, and an application management/distribution execution unit 4104.

In the following, for simplicity's sake, the process of the main control unit 401 expanding the basic operation program 4001 stored in the storage unit 410 into RAM 404 and executing it to control each operation block will be described as the basic operation execution unit 4101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The video content management/distribution execution unit 4102 acquires program content and metadata of broadcast programs from the broadcast station server 300, manages the video content and metadata stored in the video content storage area 4200 and the metadata storage area 4300, and controls the distribution of the video content and metadata to each television receiver. Furthermore, the video content management/distribution execution unit 4102 may perform authentication processing for each television receiver as needed when distributing the video content and metadata to each television receiver. Furthermore, the application management/distribution execution unit 4104 manages applications stored in the application storage area 4400 and controls the distribution of each application in response to a request from each television receiver. Furthermore, the application management/distribution execution unit 4104 may perform authentication processing for each television receiver as needed when distributing the application to each television receiver.

The LAN communication unit 421 is connected to the Internet 200 and communicates with the broadcast station server 300 on the Internet 200 and with the broadcast receiving device 100 via the router device 200r. The LAN communication unit 421 is equipped with an encoding circuit, a decoding circuit, etc.

[Hardware configuration of mobile information terminal]
10A is a block diagram showing an example of the internal configuration of a portable information terminal 700. The portable information terminal 700 is composed of a main control unit 701, a system bus 702, a ROM 703, a RAM 704, a storage unit 710, a communication processing unit 720, an expansion interface unit 724, an operation unit 730, an image processing unit 740, an audio processing unit 750, and a sensor unit 760.

The main control unit 701 is a microprocessor unit that controls the entire portable information terminal 700 in accordance with a predetermined operating program. The system bus 702 is a data communication path for transmitting and receiving data between the main control unit 701 and each operating block within the portable information terminal 700.

ROM 703 is memory that stores basic operating programs such as the operating system and other operating programs, and may be a rewritable ROM such as an EEPROM or flash ROM. RAM 704 serves as a work area when the basic operating programs and other operating programs are executed. ROM 703 and RAM 704 may be integrated with the main control unit 701. ROM 703 may also use a portion of the memory area within the storage unit 710, rather than being an independent configuration as shown in Figure 10A.

The storage unit 710 stores the operating programs and operating setting values of the mobile information terminal 700, personal information of the user of the mobile information terminal 700, etc. It can also store operating programs downloaded via the Internet 200 and various data created by the operating programs. It can also store content such as video, still images, and audio downloaded via the Internet 200. A portion of the storage unit 710 may replace all or part of the functions of the ROM 703. The storage unit 710 must also retain the information stored therein even when power is not being supplied to the mobile information terminal 700 from an external source. Therefore, devices such as non-volatile semiconductor memory such as flash ROM or SSD, or magnetic disk drives such as HDD, are used.

The operating programs stored in the ROM 703 and storage unit 710 can be added to, updated, and have their functions expanded by downloading them from each server device on the Internet 200.

The communication processing unit 720 is composed of a LAN communication unit 721, a mobile telephone network communication unit 722, and an NFC communication unit 723. The LAN communication unit 721 is connected to the Internet 200 via the router device 200r and the access point 200a, and transmits and receives data to and from each server device and other communication devices on the Internet 200. The connection to the router device 200r and the access point 200a is assumed to be wireless, such as Wi-Fi (registered trademark). The mobile telephone network communication unit 722 performs telephone communication (calls) and data transmission and reception via wireless communication with the base station 600b of the mobile telephone network. The NFC communication unit 723 performs wireless communication when in proximity to a corresponding reader/writer. The LAN communication unit 721, the mobile telephone network communication unit 722, and the NFC communication unit 723 each include an encoding circuit, a decoding circuit, an antenna, etc. Additionally, the communication processing unit 720 may further include other communication units, such as a BlueTooth (registered trademark) communication unit or an infrared communication unit.

The expansion interface unit 724 is a group of interfaces for expanding the functionality of the mobile information terminal 700, and in this embodiment is composed of a video/audio interface, a USB interface, a memory interface, etc. The video/audio interface inputs video/audio signals from external video/audio output devices, outputs video/audio signals to external video/audio input devices, etc. The USB interface connects to a PC or the like to send and receive data. It may also be used to connect a keyboard or other USB device. The memory interface connects to a memory card or other memory medium to send and receive data.

The operation unit 730 is an instruction input unit for inputting operation instructions to the mobile information terminal 700, and in this embodiment is configured with a touch panel 730t arranged on top of the display unit 741 and operation keys 730k with an array of button switches. Only one of these may be used. The mobile information terminal 700 may also be operated using a keyboard or the like connected to the extended interface unit 724. The mobile information terminal 700 may also be operated using a separate terminal device connected via wired or wireless communication. In other words, the mobile information terminal 700 may be operated from the broadcast receiving device 100. The touch panel function may also be provided by the display unit 741.

The image processing unit 740 is composed of a display unit 741, an image signal processing unit 742, a first image input unit 743, and a second image input unit 744. The display unit 741 is a display device such as an LCD panel, and provides image data processed by the image signal processing unit 742 to the user of the mobile information terminal 700. The image signal processing unit 742 is equipped with a video RAM (not shown), and the display unit 741 is driven based on image data input to the video RAM. The image signal processing unit 742 also has the function of performing format conversion and superimposing processing of menus and other OSD (On Screen Display) signals as necessary. The first image input unit 743 and second image input unit 744 are camera units that input image data of the surroundings or object by converting light input from the lens into an electrical signal using electronic devices such as a CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) sensor.

The audio processing unit 750 is composed of an audio output unit 751, an audio signal processing unit 752, and an audio input unit 753. The audio output unit 751 is a speaker, and provides the audio signal processed by the audio signal processing unit 752 to the user of the mobile information terminal 700. The audio input unit 753 is a microphone, and converts the user's voice, etc. into audio data and inputs it.

The sensor unit 760 is a group of sensors for detecting the state of the mobile information terminal 700, and in this embodiment is composed of a GPS receiver unit 761, a gyro sensor 762, a geomagnetic sensor 763, an acceleration sensor 764, an illuminance sensor 765, and a proximity sensor 766. These sensors make it possible to detect the position, inclination, direction, and movement of the mobile information terminal 700, as well as the ambient brightness and the proximity of surrounding objects. The mobile information terminal 700 may also be equipped with other sensors, such as a barometric pressure sensor.

The mobile information terminal 700 may be a mobile phone, smartphone, tablet terminal, etc. It may also be a PDA (Personal Digital Assistant) or a notebook PC. It may also be a digital still camera, a video camera capable of recording video, a portable game console, a navigation device, or any other portable digital device.

Note that the example configuration of the mobile information terminal 700 shown in Figure 10A includes many components that are not essential to this embodiment, such as the sensor unit 760, but the effects of this embodiment are not diminished even if these components are not included. Furthermore, components not shown, such as a digital broadcast reception function and an electronic money payment function, may also be added.

[Software configuration of mobile information terminal]
10B is a software configuration diagram of the mobile information terminal 700 of this embodiment, and shows the software configuration in the ROM 703, RAM 704, and storage unit 710. In this embodiment, a basic operation program 7001 and other operation programs are stored in the ROM 703, and a linkage control program 7002 and other operation programs are stored in the storage unit 710. The storage unit 710 is also assumed to include a content storage area 7200 that stores content such as moving images, still images, and audio, an authentication information storage area 7300 that stores authentication information and the like required when accessing a television receiver or each server device, and various information storage areas that store various other information.

The basic operation program 7001 stored in ROM 703 is loaded into RAM 704, and the main control unit 701 executes the loaded basic operation program to form a basic operation execution unit 7101. Similarly, the collaborative control program 7002 stored in the storage unit 710 is loaded into RAM 704, and the main control unit 701 executes the loaded collaborative control program to form a collaborative control execution unit 7102. Furthermore, RAM 704 is provided with a temporary storage area for temporarily storing data created when each operation program is executed, as needed.

In the following, for simplicity's sake, the process of the main control unit 701 expanding the basic operation program 7001 stored in ROM 703 into RAM 704 and executing it to control each operation block will be described as the basic operation execution unit 7101 controlling each operation block. Similar descriptions will be used for the other operation programs.

The linkage control execution unit 7102 manages device authentication and connection, sending and receiving of various data, etc. when the mobile information terminal 700 performs linkage operations with the television receiver. The linkage control execution unit 7102 also has a browser engine function for executing applications that link with the television receiver.

The operating programs may be stored in advance in the ROM 703 and/or storage unit 710 at the time of product shipment. After product shipment, they may be acquired from another application server 500 on the Internet 200 via the LAN communication unit 721 or mobile telephone network communication unit 722. Alternatively, the operating programs may be stored on a memory card, optical disc, etc. and acquired via the expansion interface unit 724, etc.

[Time management of broadcast receiving device]
The broadcast receiving device of this embodiment has two types of time management functions. The first time management function is a time management function based on NTP, as already explained using Figure 7C. The second time management function is a time management function based on MH-TOT, and time is managed based on the time information transmitted by MH-TOT, as explained in Figure 6B.

An example of the structure of time information transmitted by NTP is shown in Figure 13A. An example of the data structure of the MPU timestamp descriptor is shown in Figure 13B. The 'reference_timestamp' parameter and 'transmit_timestamp' parameter in the NTP format are 64-bit NTP long format time data, and the 'mpu_presentation_time' parameter in the MPU timestamp descriptor is also 64-bit NTP timestamp format time data. The NTP long format time data and the NTP timestamp format time data are data in which UTC's 'seconds or more' are represented by 32 bits and 'less than a second' by 32 bits. In other words, NTP format time information can transmit time information down to 'less than a second'. Furthermore, because the NTP format time information is in UTC notation, unlike clock management in conventional digital broadcasting, it can be matched with the NTP included in the signal received over the communication line path (for example, the communication line that can be received by the LAN communication unit 121 in Figure 7A) as shown in Figure 3(B).

In contrast, the information transmitted by MH-TOT is as follows: The broadcast receiving device 100 is assumed to be able to obtain the current date and Japan Standard Time from MH-TOT. Figure 11A shows an example of the data structure of MH-TOT. The broadcast receiving device 100 is able to obtain the current date and current time from the "JST_time" parameter of the MH-TOT. As shown in Figure 11B, the "JST_time" parameter is assumed to include the lower 16 bits of the coded data for the current date in Modified Julian Date (MJD) and 24 bits of information representing Japan Standard Time (JST) as six 4-bit binary-coded decimal (BCD) numbers. The current date can be calculated by performing a specified calculation on the 16-bit encoded data of the MJD. The six 4-bit binary coded decimal numbers consist of two 4-bit binary coded decimal numbers representing the hour in two decimal digits, the next two 4-bit binary coded decimal numbers representing the minute in two decimal digits, and the final two 4-bit binary coded decimal numbers representing the second in two decimal digits.

The difference between time based on NTP and time based on MH-TOT is that, as mentioned above, NTP transmits time information in UTC notation, which can transmit time information down to the "second," whereas the information transmitted by MH-TOT is JST notation, which transmits time information down to the "second."

The broadcast receiving device 100 of this embodiment uses a time management function based on NTP, which is time information in UTC notation, to synchronize the decoding and display of the video, audio, subtitles, superimposed text, and other presented data that make up the content of the broadcast signal, thereby achieving more accurate synchronization. Furthermore, by referencing information in UTC notation rather than the broadcast station's clock notation, it is also possible to synchronize the decoding and display of the video, audio, subtitles, superimposed text, or other data that make up the content of the broadcast signal received via the broadcast signal with the video, audio, subtitles, superimposed text, or other data acquired via the communication line path.

Furthermore, the broadcast receiving device of this embodiment can use a time management function based on "JST_time," which contains 24 bits of information expressed as six 4-bit binary-coded decimal numbers in the MH-TOT, for the process of presenting the current time to the user or for each process that handles the MH-Event Information Table (MH-EIT) described in Figure 6B. Generally, the process of presenting the current time to the user in a broadcast receiving device rarely requires precision down to the second. Furthermore, each piece of time information described in the MH-Event Information Table (MH-EIT) is stored as 24 bits of information expressed as six 4-bit binary-coded decimal numbers, with two decimal digits for "hour," "minute," and "second," similar to the EIT of conventional digital broadcasts transmitted using the MPEG2-TS format. For this reason, the MH-TOT-based time management function in the broadcast receiving device 100 of this embodiment is easily compatible with processes that use the MH-EIT. Specifically, processes that use MH-EIT include program guide generation processes (described below), control of recording and viewing reservations, and copyright management processes such as temporary storage. Precision down to the second is rarely required for any of these processes, and precision on the order of one second is sufficient.

Furthermore, the program guide generation process, recording and viewing reservation control, and copyright management processes such as temporary storage are also functions implemented in receivers of conventional digital broadcasting systems using the MPEG2-TS format. Therefore, if the broadcasting system of this embodiment is configured to handle program guide generation process, recording and viewing reservation control, copyright management processes such as temporary storage, and other processes using time management processes that are consistent with conventional MPEG2-TS digital broadcasting systems, then when configuring a broadcast receiving device that has both the functionality to receive conventional MPEG2-TS digital broadcasts and the functionality to receive MMT digital broadcasts, there will be no need to design separate processing algorithms for these processes (program guide generation process, recording and viewing reservation control, copyright management processes such as temporary storage, and other processes), thereby reducing costs.

In addition, even if a receiver only has the ability to receive MMT digital broadcasts and does not have the ability to receive conventional MPEG2-TS digital broadcasts, it can utilize the algorithms for functions that are also included in receivers for digital broadcast systems that use the conventional MPEG2-TS format, without having to create completely new algorithms for processes such as generating program guides, controlling recording and viewing reservations, and copyright management processes such as temporary storage, making development more cost-effective.

Therefore, by configuring a system that uses the time management function based on the MH-TOT "JST_time" parameter for these processes (such as program guide generation, recording and viewing reservation control, and copyright management processes such as temporary storage), it becomes possible to provide MMT digital broadcast receiving devices at a lower cost by improving compatibility with conventional broadcasting systems.

As explained above, the broadcast receiving device 100 of this embodiment has a time management function that uses two types of time information with different degrees of accuracy. One type of time information is time information written in a format that is consistent with conventional digital broadcasting systems, while the other type of time information has a higher resolution than the first type. By using the latter type of time information for synchronizing each piece of content data in the broadcast signal, more advanced information presentation processing than conventional broadcasting systems is realized, and by using the former type of time information for generating program guides, controlling recording and viewing reservations, and copyright management processing such as temporary storage, broadcast receiving devices can be provided at low cost.

Therefore, by being equipped with the two types of time management functions described above, the broadcast receiving device 100 of this embodiment can achieve both more advanced information presentation processing and lower costs.

[First Modification of Time Management]
Next, a first modification of the time management in the broadcasting system of this embodiment will be described below.

In a first variant, in order to improve the accuracy of the management time of the NTP-based time management function already described using Figure 7C, information regarding the expected delay time in transmitting time information from a time management server (not shown) or broadcast station server 300 to the broadcast receiving device 100 may be included in the broadcast signal and transmitted, and the broadcast receiving device 100 may be configured to use the information regarding the expected delay time to correct the system clock of the NTP-based time management function.

In this case, information regarding the expected delay time may be transmitted not within the TLV multiplexed stream shown in Figure 3(A) but within a TMCC (Transmission and Multiplexing Configuration Control) area outside the TLV multiplexed stream. Transmitting information within the TMCC area allows the broadcast receiving device 100 to extract information regarding the expected delay time without undergoing demultiplexing (demuxing) of the TLV multiplexed stream. In other words, it is possible to obtain information that is less affected by the delays caused by the demultiplexing process in the broadcast receiving device 100, thereby enabling highly accurate system clock adjustment processing. An example of the data structure of the time information transmitted in the TMCC signal is explained using Figure 13C. The time information may be stored and transmitted, for example, in a TMCC extended information area. In the time information in the TMCC extension information field in Figure 13C, the "delta" parameter represents the estimated transmission delay from the time management server that distributes UTC or the server device that creates the TMCC signal to a general broadcast receiving device, using a 32-bit signed fixed-point number. The upper 16 bits describe the integer part, and the lower 16 bits describe the decimal point. The "transmit_timestamp" parameter is a transmission timestamp, and describes the time when this TMCC signal is sent from the server device in NTP timestamp length format. The upper 32 bits represent the integer part, and the lower 32 bits represent the decimal point.

In this first variant, the broadcast receiving device 100 of this embodiment can more accurately correct the system clock of the NTP-based time management function used to synchronize each piece of content data in the broadcast signal, using information about the expected delay time (for example, the aforementioned "delta" parameter and/or "transmit_timestamp" parameter) described in the time information stored in the TMCC extended information area and transmitted.

[Second Modification of Time Management]
Next, a second modification of the time management in the broadcasting system of this embodiment will be described below.

As mentioned above, the broadcast receiving device 100 of this embodiment has a time management function that acquires the current date and Japan Standard Time from information transmitted via MH-TOT and manages the time. The current date and Japan Standard Time acquired from information transmitted via MH-TOT can be superimposed on video information, application information, etc. by the video synthesis unit 161 of the broadcast receiving device 100, and output to the monitor unit 162 or video output unit 163 for provision to the user. As mentioned above, MH-TOT has the data structure shown in Figure 11A, and the broadcast receiving device 100 can acquire the current date and current time from the "JST_time" parameter of the MH-TOT.

However, the aforementioned "JST_time" parameter only uses the lowest 16 bits of the MJD encoded data, which results in an overflow at "April 22, 2038," making it impossible to express dates after "April 23, 2038" using only the specified calculation. Therefore, in the second variant of this embodiment, the calculation method is switched depending on whether the MJD value is greater than or equal to a specified value or less than the specified value, allowing dates after "April 23, 2038" to be expressed.

Figure 12 shows an example of a first calculation method used when the MJD value is equal to or greater than a predetermined value, and a second calculation method used when the MJD value is less than the predetermined value. For example, if the predetermined value is 32768 (0x8000), the first calculation method is used to calculate the current date when the MJD is equal to or greater than 32768, and the second calculation method is used when the MJD is less than 32768. Note that an MJD less than 32768 is equivalent to the most significant bit of the 16-bit MJD data being 0. This makes it possible for the broadcast receiving device 100 of this embodiment to represent dates after April 23, 2038. However, the predetermined value can be set arbitrarily, and may be set to values such as 16384 (0x4000) or 49152 (0xC000). The condition for switching the calculation method may be when the most significant two bits of the 16-bit data of the MJD are "00" or when the most significant two bits of the 16-bit data of the MJD are not "11." Note that if the above-mentioned method is used with the predetermined value set to "32768," dates prior to "September 4, 1948" cannot be represented, but this does not pose any particular problem in practical use as a television receiver.

In addition, rather than switching between the first and second calculation methods based on the comparison result between the MJD and the predetermined value, the first and second calculation methods may be switched based on a flag that replaces part or all of the "reserved" parameter in the MH-TOT data structure shown in FIG. 11A or a newly added flag. For example, if the most significant bit of the 16-bit encoded data of the MJD is "0," the flag may be set to "1" if the MJD indicates "April 23, 2038" or later, or set to "0" if the MJD does not indicate "April 23, 2038" or later. Then, if the flag is "1," the second calculation method shown in FIG. 12 may be used, and if the flag is "0," the first calculation method may be used. Alternatively, a new descriptor having the same meaning as the flag may be prepared and placed in the MH-TOT.

Furthermore, as mentioned above, the broadcasting system of this embodiment transmits absolute time in NTP format, and the broadcast receiving device 100 of this embodiment has a time management function based on this NTP. Furthermore, the broadcast receiving device 100 of this embodiment controls the decoding timing and presentation timing for each presentation unit of video/audio signals by referencing the NTP timestamp etc. described in the MPU timestamp descriptor set on an MPU basis. As mentioned above, the time information in NTP format has the structure shown in Figure 13A. Furthermore, the MPU timestamp descriptor has the structure shown in Figure 13B.

For this reason, the broadcast receiving device 100 of this embodiment may refer to the "reference_timestamp" parameter, the "transmit_timestamp" parameter, or the "mpu_presentation_time" parameter, and select whether to use the first or second calculation method depending on the value of the referenced time data, etc. In other words, for example, if the most significant bit of the 64-bit NTP-length format time data is "0", the second calculation method may be used, and if it is not "0", the first calculation method may be used.

Using either of the above methods, the broadcast receiving device 100 of this embodiment can represent dates after April 23, 2038.

[Broadcast receiving device channel selection process (initial scan)]
The AMT of the broadcasting system of this embodiment provides a list of multicast groups for IP packets so that IP packets transmitted by the TLV multiplexing method can be received without distinction from IP packets transmitted over a communication line as much as possible. Multiple IP multicast groups can be listed for one service identifier. Address masks can also be used to efficiently describe consecutive IP addresses.

In the broadcast receiving device 100 of this embodiment, when scanning channels during initial setup or when rescanning to change settings, it is possible to store a list of services obtained from the TLV-NIT in non-volatile memory such as ROM 103 or storage unit 110. Furthermore, it is possible to associate a list of IP multicast groups corresponding to each of the services with each service as IP-related information and store it in the non-volatile memory. By storing the list of services and IP-related information in non-volatile memory and making them available for constant reference, it is no longer necessary to re-acquire the TLV-NIT or AMT when switching channels, etc., and broadcast content can be obtained more efficiently.

Figure 14 shows an example of the operational sequence during channel scanning (rescanning) in the broadcast receiving device 100 of this embodiment.

When channel scanning begins, the reception function execution unit 1102 sets an initial frequency value to the tuner/demodulator unit 131 and instructs it to tune to that frequency value (S101). If the tuner/demodulator unit 131 successfully locks onto the set frequency value (S102: Yes), the reception function execution unit 1102 then acquires the TLV-NIT from the received signal (S103).

If the TLV-NIT acquired in the processing of S103 is valid data (S104: Yes), the reception function execution unit 1102 acquires information such as the TLV stream ID and original network ID from the acquired TLV-NIT (S105). Figure 15A shows an example of the data structure of a TLV-NIT. The TLV stream ID information can be acquired from the 'tlv_stream_id' parameter, and the original network ID information can be acquired from the 'original_network_id' parameter. Furthermore, distribution system information regarding the physical conditions of the broadcast transmission path corresponding to each TLV stream ID/original network ID is acquired from the distribution system descriptor (S106), and a list of service IDs is acquired from the service list descriptor (S107). Figure 15B shows an example of the data structure of a satellite distribution system descriptor. Figure 15C shows an example of the data structure of a service list descriptor. If the TLV-NIT contains multiple different pieces of data, such as a TLV stream ID, original network ID, distribution system information, and list of service IDs, steps S105 to S107 are repeated. Next, the reception function execution unit 1102 creates a service list based on the data obtained in steps S105 to S107, such as the TLV stream ID, original network ID, distribution system information, and list of service IDs, and stores the created service list in the ROM 103 or storage unit 110 (updated when rescanning) (S108).

Next, the reception function execution unit 1102 acquires the AMT from the received signal (S109), and further acquires a list of IP multicast groups for each service ID stored in the service list (S110). Figure 15D shows an example of the data structure of an AMT. Note that if the AMT has lists of IP multicast groups for multiple service IDs, the process of S110 is repeated. If there are multiple AMTs with lists of IP multicast groups for different service IDs, the processes of S109 to S110 are repeated. Next, the reception function execution unit 1102 associates the list of IP multicast groups acquired in the process of S110 with the service ID as IP-related information and stores it in the ROM 103 or storage unit 110 (updated when rescanning) (S111).

Note that if the tuner/demodulator unit 131 does not successfully lock onto the set frequency value in the process of S102 (S102: No), or if the TLV-NIT acquired in the process of S103 is not valid data (S104: No), the processes of S105 to S111 are not performed.

After completing the process of S111, the reception function execution unit 1102 ends the process if the frequency value set in the tuner/demodulator unit 131 is the final frequency value in the channel scan range (S112: Yes). On the other hand, if the set frequency value is not the final frequency value in the channel scan range (S112: No), the frequency value set in the tuner/demodulator unit 131 is increased (S113), and the processes of S102 to S111 are repeated. Note that if a single TLV-NIT can acquire service IDs for all services that make up the broadcast network, and if an AMT containing a list of IP multicast groups related to the service IDs can be acquired, the processes of S112 to S113 are not necessary.

Through the above-described series of processes, the broadcast receiving device 100 of this embodiment creates/updates a list of services (service list) that make up the broadcast network when scanning channels during initial setup or when rescanning to change settings, and at the same time creates/updates a list of IP multicast groups (IP-related information) corresponding to each of the services, and can then store this information in non-volatile memory such as ROM 103 or storage unit 110.

The rescan for the setting change may be performed automatically when a change in the information in the table is detected by referencing the "version_number" parameter in the TLV-NIT or AMT. When a change in the "version_number" parameter in either the TLV-NIT or AMT is detected, only the information related to the table in which the change in the parameter was detected may be automatically updated. However, when the automatic update is performed, it is desirable to notify the user that a rescan has been performed automatically. Alternatively, the user may be notified that a change has been made to the information in the table, and the user may be allowed to choose whether or not to perform the rescan.

[Broadcast receiving device tuning process (channel switching)]
FIG. 16 is a diagram showing an example of an operation sequence when selecting a station (switching channels) in the broadcast receiving device 100 of this embodiment.

When a user operates a remote control (not shown) to instruct a channel change, the reception function execution unit 1102 interprets the command sent from the remote control and specifies the service ID of the desired service (S201). Next, the reception function execution unit 1102 begins acquiring an AMT from the signal received by the tuner/demodulator unit 131. If the AMT is successfully acquired within a predetermined time (S202: Yes), information regarding a list of IP multicast groups corresponding to the service ID is acquired from the acquired AMT (S204). On the other hand, if the AMT is not successfully acquired within the predetermined time (S202: No), information regarding a list of IP multicast groups corresponding to the service ID is acquired by referencing IP-related information stored in the ROM 103 or storage unit 110 (S203). Note that the determination process of S202 may not be performed, and the IP-related information stored in the ROM 103 or storage unit 110 may always be referenced.

Next, the reception function execution unit 1102 begins acquiring the TLV-NIT from the signal received by the tuner/demodulator unit 131. If the TLV-NIT is successfully acquired within the specified time (S205: Yes), distribution system information for acquiring the IP data flow corresponding to the service ID is acquired from the acquired TLV-NIT (S207). On the other hand, if the TLV-NIT is not successfully acquired within the specified time (S205: No), distribution system information for acquiring the IP data flow corresponding to the service ID is acquired (S207) by referring to a service list stored in ROM 103 or storage unit 110, etc. (S206). Note that it is also possible to always refer to a service list stored in ROM 103 or storage unit 110, etc., without performing the judgment process of S205. After acquiring the distribution system information in the processing of S207, the reception function execution unit 1102 then controls the tuner/demodulation unit 131 with the frequency value indicated in the acquired distribution system information, receives the IP data flow corresponding to the service ID (S208), extracts the MMT data string from the received IP data flow, and outputs it to the separation unit 132.

In the separation unit 132, the transport processing unit 1102a acquires an MMTP packet whose packet ID is "0" from the input MMT data sequence (S209), and further acquires the MPT contained in the acquired MMTP packet (S210). Next, the transport processing unit 1102a references the "MMT_package_id_byte" parameter contained in the acquired MPT and confirms whether the lowest 16 bits of the "MMT_package_id_byte" parameter are the same value as the service ID. In the example data structure of the MPT shown in Figure 17, if the lowest 16 bits of the "MMT_package_id_byte" parameter have the same value as the service ID (S211: Yes), it is determined that the MMTP packet whose packet ID is "0" is an MMTP packet containing data for the program corresponding to the service ID, and an MFU is obtained based on the information contained in the obtained MPT (S216).

On the other hand, if the lowest 16 bits of the "MMT_package_id_byte" parameter are not the same value as the service ID (S211: No), the MMTP packet with the packet ID of "0" is determined to not be an MMTP packet containing program data corresponding to the service ID. In this case, the transport processing unit 1102a acquires the PLT again (S212) and checks the acquired PLT to confirm the packet ID (assumed to be x) of the MMTP packet transmitting the MPT containing the "MMT_package_id_byte" parameter corresponding to the service ID (S213). Furthermore, the transport processing unit 1102a acquires an MMTP packet with a packet ID of "x" from the input MMT data sequence (S214) and acquires the MPT contained in the acquired MMTP packet (S215). Furthermore, the transport processing unit 1102a acquires an MFU based on the information contained in the acquired MPT (S216).

It is also possible to skip steps S209 to S211 and always perform steps S212 to S215. In this case, processing time can be shortened when program data corresponding to the service ID is stored in an MMTP packet with a packet ID other than "0."

When the MFU is acquired in the processing of S216, the transport processing unit 1102a extracts encoded video data, encoded audio data, etc. from the acquired MFU and outputs them to the video decoder 141, audio decoder 143, etc. Next, video/audio decoding processing is performed under the control of the AV decoding processing unit 1102b, and presentation processing is performed under the control of the presentation processing unit 1102h, but since each of these processes is publicly known, detailed explanations will be omitted.

The above series of processes enable the broadcast receiving device 100 of this embodiment to perform channel selection (channel switching) operations. In particular, as described using Figures 14 and 16, when scanning channels during initial setup or when rescanning to change settings, a service list and IP-related information are created and stored in non-volatile memory such as ROM 103 or storage unit 110 for continuous reference. When selecting a channel (switching a channel), the service list and IP-related information stored in non-volatile memory such as ROM 103 or storage unit 110 are referenced, thereby improving the efficiency of channel selection (channel switching). In other words, the time from the start of channel selection (channel switching) to the end of channel selection (channel switching) can be shortened compared to when re-acquiring AMT or TLV-NIT during channel selection (channel switching).

[Screen layout control of broadcast receiving device]
It is assumed that the broadcast receiving device 100 of this embodiment is capable of controlling the screen layout based on the description of the LCT. An example of the data structure of the LCT is shown in FIG.

In the diagram, the "left_top_pos_x" and "right_down_pos_x" parameters indicate the horizontal position of the top left and bottom right of the region, respectively, as a percentage of the total number of horizontal pixels, when the left side of the full-screen display is "0" and the right side is "100". The "left_top_pos_y" and "right_down_pos_y" parameters indicate the vertical position of the top left and bottom right of the region, respectively, as a percentage of the total number of vertical pixels, when the top side of the full-screen display is "0" and the bottom side is "100". The "layer_order" parameter indicates the relative position of the region in the depth direction.

Figures 19A-D show examples of layout assignments to layout numbers based on the settings of each of the above parameters, along with the setting values of each of the above parameters.

Figure 19A shows the default layout setting for the broadcast receiving device 100 of this embodiment, an example in which only one area is set across the entire screen. Figure 19B shows an example in which the entire screen is divided into three areas, each designated "Area 0," "Area 1," and "Area 2." For example, if the number of pixels across the entire screen is 7,680 horizontally and 4,320 vertically, "Area 0" is set to the range (0,0)-(6,143,3,455) because the "left_top_pos_x" parameter is "0," the "left_top_pos_y" parameter is "0," the "right_down_pos_x" parameter is "80," and the "right_down_pos_y" parameter is "80." Similarly, "Area 1" is set to the range (6144,0)-(7679,4319), and "Area 2" is set to the range (0,3456)-(6143,4319).

Figure 19C shows an example of setting three regions, similar to Figure 19B, but "Region 0" is set in the range (0,0)-(7679,4319), and "Region 1" and "Region 2" are placed in front of "Region 0" in the same range as above, depending on the setting of the "layer_order" parameter. Figure 19D shows an example where "Region 0" is set to Device 0 (the default device: in this example, the broadcast receiving device 100), and "Region 1" is set to Device 1 (in this example, the mobile information terminal 700).

As mentioned above, in the broadcasting system of this embodiment, by using LCT, it is possible to control the screen layout so that multimedia services are displayed on the receiver as intended by the service provider.

When dividing the screen according to the setting values of parameters such as "left_top_pos_x", any fractional part after the decimal point can be rounded up or down. Rounding (or rounding to the nearest integer in binary numbers) is also acceptable. For example, if the total screen pixel count is 7680 pixels x 4320 pixels vertically, and the "left_top_pos_x" parameter of "Area 0" is "0," the "left_top_pos_y" parameter is "0," the "right_down_pos_x" parameter is "51," and the "right_down_pos_y" parameter is "51," "Area 0" may be set to the range (0,0)-(3916,2203) by rounding up, or to the range (0,0)-(3915,2202) by rounding down. Furthermore, taking into account macroblocks during video compression processing, rounding up/down may be performed in 8-pixel or 16-pixel units. This processing enables efficient area setting based on the LCT and resolution conversion of multimedia content in the area.

[Exception handling of screen layout control in broadcast receiving device]
In the broadcast receiving device 100 of this embodiment, even when the screen layout area control is performed by the above-mentioned LCT, if the user instructs to display an EPG screen, etc., it is possible to perform screen layout control that ignores the contents of the LCT as an exceptional process. Figure 20A shows an example of the operation of exceptional process for screen layout control based on the LCT.

When the same screen layout control as in Figure 19B is performed based on the LCT description, and broadcast program video is displayed in "Area 0," and broadcast content such as program linked data linked to the broadcast program is displayed in "Area 1" and "Area 2," and the user instructs the display of the EPG screen using a remote control (not shown), the broadcast receiving device 100 of this embodiment returns the screen layout setting to the default setting (i.e., a state in which the same screen layout control as in Figure 19A is being performed) regardless of the contents of the LCT description, as shown in Figure 20A (A), and controls the EPG screen to be displayed on the entire screen. Furthermore, when the user instructs the display of the EPG screen to end, the screen layout control is re-executed in accordance with the contents of the LCT description.

By performing the above-described control, the EPG screen can be displayed larger and easier to view than when the EPG screen is displayed while maintaining area control of the screen layout, as shown in Figure 20A (B).

Note that the above-mentioned exception processing of screen layout control is not only applied when displaying the EPG screen, but may also be applied when displaying a sub-screen or dual-screen display of various setting screens (the recording setting screen in the illustrated example) of the broadcast receiving device 100, as shown in Figure 20B.

In the case of the recording setting screen shown in Figure 1A, the display area for the broadcast content changes from the entire screen to only the sub-screen portion in the lower right corner of the screen. Similarly, in the case of the dual-screen display shown in Figure 1B, the display area for the broadcast content changes from the entire screen to only the split-screen portion in the middle left corner of the screen. In either case, the display area for displaying the broadcast content is narrower than when the entire screen is used, so maintaining area control of the screen layout within the display area (i.e., dividing the area and displaying multiple broadcast contents simultaneously) is not desirable from a visual standpoint. Therefore, in the broadcast receiving device 100 of this embodiment, in the above situation, only the broadcast content in "Area 0" is selected and displayed in the display area. Note that it is also possible to select and display broadcast content in "Area 1" or "Area 2" depending on the previous area selection status.

By performing the above-mentioned control, it is possible to improve the ease of viewing broadcast content compared to when various broadcast content is displayed while maintaining area control of the screen layout. The same is true when displaying a sub-screen on the recorded program list screen, displaying internet content in a browser, etc.

[EPG display on broadcast receiving device]
In the broadcasting system of this embodiment, time-series information regarding events (so-called programs) included in each service constituting the broadcasting network is transmitted via the MH-EIT. FIG. 21 shows an example of the data structure of the MH-EIT of this embodiment. The MH-EIT is identified into two classes by a table ID (corresponding to the "table_id" parameter in the figure) and is capable of indicating information on the current/next event of its own TLV stream and schedule information for each event of its own TLV stream. The broadcast receiving device 100 of this embodiment refers to the MH-EIT and performs identification by service ID (corresponding to the "service_id" parameter in the figure), thereby obtaining information such as the start time and broadcast time of each event and creating an EPG screen. The created EPG can be superimposed on video information, etc., by the video synthesis unit 161 and displayed on the monitor unit 162.

Figure 22A shows an example of an EPG screen in the broadcast receiving device 100 of this embodiment. The EPG screen 162a is in a matrix format with the vertical axis representing time and the horizontal axis representing service ID (channel), and displays detailed information about broadcast programs broadcast on each channel during each time period. The detailed information 162a1 for each broadcast program is primarily composed of a title area 162a2 and a detailed description area 162a3.

The title area 162a2 displays the program title of the broadcast program and symbols or the like representing the attributes of the broadcast program. Symbols or the like representing the attributes of the broadcast program include, for example, symbols/letters indicating that it is a new program or a rebroadcast program. Alternatively, they may be a symbolized symbol for "data," indicating that the program is compatible with data broadcasting via a broadcast service. They may also be a symbolized symbol for "Network" 162a4, indicating that content, applications, etc. related to the broadcast program can be obtained from the network. Symbols or the like representing the attributes of the broadcast program may also be displayed by using a different background color for the detailed information 162a1 or by surrounding the display area of the detailed information 162a1 with a bold frame.

Incidentally, even if the control information (messages, tables, descriptors, etc.) in the broadcasting system of this embodiment indicates that content, applications, etc. related to the broadcast program can be obtained from the network, if the LAN cable is not connected to the LAN communication unit 121 of the broadcast receiving device 100, or if access to the server devices on the network is not possible, the mark 162a4 symbolizing "Network" etc. may be controlled not to be displayed.

Furthermore, if the broadcast program is a distributed program distributed via the Internet 200 and cannot be acquired solely from broadcast waves, and further, as described above, if the broadcast receiving device 100 is unable to access the server devices on the network, the detailed information 162b1 displayed on the EPG screen 162b may be controlled to be grayed out, as shown in FIG. 22B. In other words, the detailed information of the distributed program that cannot be viewed is controlled not to be displayed. Alternatively, the graying out process may be performed by differentiating the background color of the detailed information 162b1 from the others. When the detailed information 162b1 is selected by operating the remote control (not shown), the user may be notified by a pop-up or the like that the broadcast receiving device 100 is unable to access the server devices on the network or that the distributed program associated with the detailed information 162b1 cannot be viewed.

Through the above-mentioned controls, the broadcast receiving device 100 is able to provide program information for each broadcast program in a format that feels more natural to the user, depending on the network connection status.

Figure 22C is a diagram showing another example of an EPG screen in the broadcast receiving device 100 of this embodiment. In the figure, "M1 Television," "M2 Broadcast," "M3 Channel," "M4 TV," "Television M5," etc. are the names of the broadcast stations for each channel, and in particular, the "M2 Broadcast" station simultaneously provides broadcast programs distributed via airwaves and distributed programs distributed via the Internet 200 (slot information 162c1 indicated by "Internet Broadcast" in the figure).

As shown in the figure, when there is a channel that only has programs distributed via the Internet 200, the EPG screen 162c in the figure (A) is normally controlled to display information for all channels (including information 162c1). On the other hand, if the broadcast receiving device 100 is unable to access each server device on the network, the EPG screen 162d in the figure (B) may be controlled not to display information for the "M2 Broadcast (Internet Broadcast)" channel (information 162c1 in the figure (A)), which only has programs distributed via the Internet 200.

The above-mentioned controls enable users of the broadcast receiving device 100 to avoid having to check information about channels that they cannot watch.

[Emergency warning broadcast display on broadcast receiving device]
The broadcast receiving device 100 of this embodiment is capable of receiving emergency alert broadcasts when the emergency alert broadcast activation control signal bit of the TMCC signal contained in the transmission data including the TLV stream changes from "0" to "1."

The emergency alert broadcast may be provided as a full-screen application, or as text information with superimposed text. When the emergency alert broadcast is provided as text information with superimposed text, it is preferable to display the superimposed text regardless of the state of the broadcast receiving device 100 immediately before the emergency alert broadcast was received. That is, as shown in FIG. 23, if an emergency alert broadcast is received while the user is watching a regular broadcast program and the program screen 162e of the broadcast program is displayed on the monitor unit 162, the text information 162e1 from the emergency alert broadcast is superimposed on the program screen 162e. Similarly, if the user instructs the display of an EPG screen and the EPG screen 162f is displayed on the monitor unit 162 and the emergency alert broadcast is received, the text information 162f1 from the emergency alert broadcast is controlled to be superimposed on the EPG screen 162f.

With the above-described control, in the broadcast receiving device 100 of this embodiment, when an emergency alert broadcast is received, it is possible to avoid missing important text information based on the emergency alert broadcast, even if the user has selected and displayed an EPG screen, various setting screens, a recorded program list screen, an internet browser, etc. This control may also be applied to text information in regular superimposed text that is not based on emergency alert broadcasts.

[Various exception handling]
If the broadcast receiving device 100 of this embodiment cannot acquire data outside the TLV stream in the same package, it may perform exception processing such as the following.

As explained in Figure 6E, in the broadcast system supported by the broadcast receiving device 100 of this embodiment, data obtained within the TLV stream and data obtained via a path other than the TLV stream can be included in the same package based on the location information stored in the MPT (corresponding to "MMT_general_location_info()" in Figure 17). However, data transmission paths other than the TLV stream indicated by the location information (e.g., IPv4 data flow, IPv6 data flow, broadcast MPEG2-TS, etc.) are reception functions separate from the TLV/MMT stream reception function. Therefore, even when the broadcast receiving device 100 is operating, there may be situations in which data cannot be obtained from these transmission paths, such as when the reception functions for these transmission paths are not operating, when the reception functions themselves are operating but relay devices or the like are not operating, when these transmission paths are not connected via wired or wireless connections, or when the broadcast receiving device 100 is installed in an environment where these transmission paths cannot be connected in the first place.

Under such circumstances, when an event is received in which the location information stored in the MPT indicates that data obtained within the TLV stream and data obtained via a route other than the TLV stream should be associated so as to be included in the same package, the broadcast receiving device 100 of this embodiment may perform, for example, the following operations.

For example, if an LCT defines multiple regions within a screen, as shown in Figures 19B and 19C, and the video contained in the TLV stream is displayed in "Area 0," and data obtained via a transmission path other than the TLV stream is displayed in "Area 1" and "Area 2," and if data from a transmission path other than the TLV stream that should be displayed in "Area 1" or "Area 2" cannot be obtained, the layout display of the multiple regions specified by the LCT may be prohibited. Specifically, even when the LCT is received, the video of the content received in the TLV stream may remain displayed in "Area 0" of the default layout display shown in Figure 19A, and a transition to a multi-region layout display such as that shown in Figures 19B and 19C may not be made. Furthermore, even if an instruction to change from the default layout to the layout indicated by the LCT is input to the operation input unit 170 of Figure 7A in this state, the default layout display shown in Figure 19A may remain, or a transition to a multi-region layout display such as that shown in Figure 19B or 19C may be made, by, for example, switching to another data broadcasting screen.

As another example of operation when the LCT sets multiple regions on the screen as shown in Figures 19B and 19C, with video contained in the TLV stream displayed in "Area 0" and data acquired via a transmission path other than the TLV stream displayed in "Area 1" and "Area 2," and data from a transmission path other than the TLV stream to be displayed in "Area 1" or "Area 2" cannot be acquired, the display frames for the multiple regions shown in Figures 19B and 19C indicated by the LCT may be temporarily displayed, and a background color or a specified still image may be displayed in "Area 1" or "Area 2." If data from a transmission path other than the TLV stream indicated by the MPT location information cannot be acquired after a specified time has elapsed, the display may be switched back to the default layout display shown in Figure 19A. In this case, it is preferable to continue displaying the program video contained in the TLV stream in "Area 0" even when the layout of Figures 19A, 19B, and 19C is changed, as this will allow the user's program video to continue.

Furthermore, when the video of the content received in the TLV stream is displayed in "Area 0" of the default layout display shown in Figure 19A due to the inability to obtain data from transmission paths other than the TLV stream to be displayed in "Area 1" or "Area 2," the various communication functions and reception functions of the broadcast receiving device 100 of this embodiment may begin to operate, or the communication environment or communication status of the various communication functions or the reception environment or reception status of the various reception functions may change, resulting in a situation where data from transmission paths other than the TLV stream to be displayed in "Area 1" or "Area 2" may become available. In this case, the broadcast receiving device 100 of this embodiment may immediately switch from the default layout display shown in Figure 19A to a multi-area layout such as those shown in Figures 19B and 19C indicated by the LCT, displaying the video of the content received in the TLV stream in "Area 0," and displaying data obtained from transmission paths other than the TLV stream in "Area 1" or "Area 2." Alternatively, the layout change may not be performed immediately, but may be performed after an instruction to change from the default layout to the layout indicated by the LCT is input from the operation input unit 170.

[Copyright protection function]
In a digital broadcasting system compatible with the broadcast receiving device 100 of this embodiment, by transmitting copy control information included in the MPT, the copy control information may be configured to transmit information indicating the copy control status of the content referenced by the MPT, such as "unlimited copying permitted" (which may be divided into two types: "unlimited copying permitted with encryption required for storage and output" and "unlimited copying permitted with encryption not required for storage and output"), "one generation copying permitted,""a specified number of copies permitted" (for example, "dubbing 10" where nine copies permitted and one move permitted) or "copy prohibited." In this case, the broadcast receiving device 100 of this embodiment may be configured to control the storage of the content in the storage (storage) unit 110, recording on a removable recording medium, output to an external device, copying to an external device, moving to an external device, and the like, in accordance with the copy control information. Note that the storage process may not only target the storage (storage) unit 110 within the broadcast receiving device 100, but may also include recordings that have been protected by encryption or other means so that they can only be played on the broadcast receiving device 100. Specifically, the targets of the storage process include external recording devices and the like that are in a state where recording and playback can be performed only by the broadcast receiving device 100 .

Specific examples of processing based on this copy control information are described below.

First, if the copy control information included in the MPT indicates "unlimited copying permitted," the broadcast receiving device 100 of this embodiment may store in the storage unit 110, record on a removable recording medium, output to an external device, copy to an external device, and move to an external device without any restrictions. However, if there is a distinction between "unlimited copying permitted but encryption processing required for storage and output" and "unlimited copying permitted but encryption processing not required for storage and output," in the case of "unlimited copying permitted but encryption processing required for storage and output," storage in the storage unit 110, recording on a removable recording medium, output to an external device, copy to an external device, and move to an external device may be performed an unlimited number of times, but encryption processing is required for all of them.

Furthermore, if the copy control information included in the MPT indicates "copyable for one generation only," the broadcast receiving device 100 of this embodiment will allow the content to be encrypted and stored in the storage unit 110, but when the stored content is output to an external device for viewing, it will be encrypted and output together with the copy control information indicating "copy prohibited." However, so-called move processing to an external device (copying the content to an external device and making the content in the storage unit 110 of the broadcast receiving device 100 unplayable by erasing the content, etc.) is permitted.

Furthermore, if the copy control information included in the MPT indicates "copyable a specified number of times," the broadcast receiving device 100 of this embodiment will encrypt and store the content in the storage unit 110, but when outputting the stored content to an external device for viewing, it will be encrypted and output together with copy control information indicating "copy prohibited." However, it may be possible to copy and move a predetermined number of times to an external device. In the case of the so-called "Dubbing 10" standard, it may be possible to copy to an external device nine times and move once.

Furthermore, if the copy control information included in the MPT indicates "copy prohibited," the broadcast receiving device 100 of this embodiment prohibits copying to the storage unit 110. However, if the broadcast receiving device 100 is configured to have a "temporary storage" mode that allows storage in the storage unit 110 for only a predetermined period of time or a predetermined period of time specified by control information included in the broadcast signal (for example, the MH-Expire descriptor shown in Figure 6D), the content can be temporarily stored in the storage unit 110 even if the copy control information included in the MPT indicates "copy prohibited." When content whose copy control information included in the MPT indicates "copy prohibited" is output for viewing on an external device, it is encrypted and output together with the "copy prohibited" copy control information.

Note that output for viewing to the aforementioned external device may be performed via the video output unit 163 and audio output unit 166 in FIG. 7A, or via the digital I/F unit 125 or LAN communication unit 121, etc. Copying or moving to the aforementioned external device may be performed via the digital I/F unit 125 or LAN communication unit 121, etc. in FIG. 7A.

The process described above enables appropriate content protection to be achieved according to the copy control information associated with the content.

In addition, copying of content whose copy control information indicates copy restrictions such as "copyable for one generation only," "copyable a specified number of times," or "copying prohibited" to an external device via the LAN communication unit 121 may be permitted only if the IP address of the external device that is the destination of the packet sent from the broadcast receiving device 100 is within the same subnetwork as the IP address of the broadcast receiving device 100, and may be prohibited if the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100. Content whose copy control information indicates "unlimited copying permitted but requires encryption processing when stored and output" may also be handled in the same manner.

Similarly, the process of moving content whose copy control information indicates copy restrictions such as "copyable for one generation only," "copyable a specified number of times," or "unlimited copying with encryption required when storing and outputting" to an external device via the LAN communication unit 121 after it has been stored in the storage unit 110 is only permitted if the IP address of the external device that is the destination of the packet sent from the broadcast receiving device 100 is within the same subnetwork as the IP address of the broadcast receiving device 100, and may be prohibited if the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100.

In principle, video and audio output for viewing content stored in the storage (accumulation) unit 110 of the broadcast receiving device 100 is only possible if the IP address of the external device that is the destination of the packet transmitted from the broadcast receiving device 100 is within the same subnetwork as the IP address of the broadcast receiving device 100. This is prohibited if the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100. However, if the external device has been connected within the same subnetwork as the IP address of the broadcast receiving device 100 within a specified period of time and has been registered (paired) as a device that can be viewed even outside the same subnetwork as the IP address of the broadcast receiving device 100, the external device may be configured to enable video and audio output for viewing content stored in the storage (accumulation) unit 110 of the broadcast receiving device 100, even if the IP address of the external device is outside the same subnetwork as the IP address of the broadcast receiving device 100. In this case, the video and audio output for viewing is performed after the content is encrypted.

The processing described above allows different processing to be performed depending on whether the external device is located within the same subnetwork as the IP address of the broadcast receiving device 100 or outside the same subnetwork, thereby achieving both user convenience and content protection.

Next, as explained in Figure 6E, in the digital broadcasting system supported by the broadcast receiving device 100 of this embodiment, location information in the MPT ('MMT_general_location_info()' in Figure 17) means that data obtained via a different route (IPv4, IPv6, MPEG2-TS, URL, etc.) than the data obtained via the TLV stream on the broadcast route may be included in the same package and event as the data obtained via the TLV stream. This section explains content protection when copy control information is included in the MPT in this case.

First, if copy control information is included in the MPT, data included in the same package and event in the location information may be controlled in accordance with the copy control information included in the TLV stream, even if the data was obtained via a different path (IPv4, IPv6, MPEG2-TS, URL, etc.) than the data obtained via the TLV stream of the broadcast path. The copy control status of the content specified by this copy control information can be, as mentioned above, "unlimited copying allowed" (which may be divided into two types: "unlimited copying allowed with encryption required for storage and output" and "unlimited copying allowed with no encryption required for storage and output"), "one generation only," "a specified number of copies allowed" (for example, 9 copies allowed + 1 move allowed is known as "dubbing 10"), or "no copying allowed."

Here, if the data position indicated by the location information includes MPEG2-TS data transmitted in another digital broadcast signal, that MPEG2-TS data is also broadcast in association with copy control information in that other digital broadcast signal. This raises the question of how and according to which information copy control of that MPEG2-TS data should be performed (should it be according to the copy control information contained in the TLV/MMT stream, or the copy control information contained in the MPEG2-TS itself?).

In the digital broadcasting system of this embodiment, to solve this problem, the broadcast receiving device 100 can perform one of the following solutions:

<Operation example 1>
In a first operation example, when copy control information is included in the MPT and data included in the same package and the same event in the location information includes MPEG2-TS data transmitted in another digital broadcast signal, the copy control state indicated by the copy control information included in the TLV stream is given priority over the copy control state indicated by the copy control information included in the MPEG2-TS.

For example, if the copy control status indicated by the copy control information contained in the TLV stream is "one-generation copy permitted" and the copy control status indicated by the copy control information contained in the MPEG2-TS is "a specified number of copies permitted," then even if the data was acquired via a different path than the data acquired in the TLV stream (digital broadcast in MPEG2-TS transmission format), copy control may be performed on the data as "one-generation copy permitted" content. For example, if the copy control status indicated by the copy control information contained in the TLV stream is "unlimited copying permitted" and the copy control status indicated by the copy control information contained in the MPEG2-TS is "specified number of copies permitted," copy control may be performed on the data as "unlimited copying permitted" content, even if the data was acquired via a different path than the data acquired in the TLV stream (digital broadcast in MPEG2-TS transmission format).

With this operation, data acquired via routes other than TLV streams can also be put into the copy state that you want to manage in the broadcast system supported by the broadcast receiving device 100 of this embodiment.

<Operation example 2>
In a second operation example, when copy control information is included in the MPT and data included in the same package and the same event in the location information includes MPEG2-TS data transmitted in another digital broadcast signal, the copy control state indicated by the copy control information included in the TLV stream is compared with the copy control state indicated by the copy control information included in the MPEG2-TS, and if the copy control state indicated by the copy control information included in the MPEG2-TS is stricter than the copy control state indicated by the copy control information included in the TLV stream, the MPEG2-TS data is excluded from the content to be processed when performing accumulation processing in the storage unit 110 or the like, recording processing on a removable recording medium, or output processing from a digital interface.

In this operation, for data acquired via a route other than the TLV stream, duplication of copy control states on the broadcast receiving device 100 of this embodiment can be eliminated while respecting the original copy control information set by the broadcast system transmitting the data.

Furthermore, if the comparison shows that the copy control status indicated by the copy control information contained in the MPEG2-TS is the same as or more lenient than the copy control status indicated by the copy control information contained in the TLV stream, then copy control can be performed on the MPEG2-TS data contained in the same package and event using that location information as content with the copy control status indicated by the copy control information contained in the TLV stream.

In this operation, for data acquired via a route other than the TLV stream, duplication of copy control states on the broadcast receiving device 100 of this embodiment can be eliminated while respecting the original copy control information set by the broadcast system transmitting the data.

In the above explanation, the copyright protection function of the broadcast receiving device 100 of this embodiment has been described as being performed based on the copy control information contained in the MPT. However, the table in which the copy control information is placed is not limited to the MPT. It may also be placed and transmitted in the MH-Service Description Table (MH-SDT) or MH-Event Information Table (MH-EIT) described in Figure 6B, or in other tables, and the broadcast receiving device 100 may perform copyright protection processing in accordance with these.

According to the present embodiment described above, it is possible to provide a broadcast receiver compatible with MMT digital broadcasting.
Example 2

The following describes Example 2 of the present invention. Note that the configuration, processing, effects, etc. of this example are the same as those of Example 1 unless otherwise specified. For this reason, the following mainly describes the differences between this example and Example 1, and explanations of common points will be omitted as much as possible to avoid duplication. Furthermore, the following description will be given assuming that the broadcast receiving device of this example is a television receiver that supports both the MMT and MPEG2-TS media transport formats.

[Hardware configuration of broadcast receiving device]
24 is a block diagram showing an example of the internal configuration of a broadcast receiving device 800. The broadcast receiving device 800 is composed of a main control unit 801, a system bus 802, a ROM 803, a RAM 804, a storage unit 810, a LAN communication unit 821, an expansion interface unit 824, a digital interface unit 825, a first tuner/demodulation unit 831, a second tuner/demodulation unit 832, an MMT decoding processing unit 841, an MPEG2-TS decoding processing unit 842, a video synthesis unit 861, a monitor unit 862, a video output unit 863, an audio synthesis unit 864, a speaker unit 865, an audio output unit 866, and an operation input unit 870.

The main control unit 801, system bus 802, ROM 803, RAM 804, storage unit 810, expansion interface unit 824, digital interface unit 825, monitor unit 862, video output unit 863, speaker unit 865, audio output unit 866, operation input unit 870, etc. have equivalent functions to the main control unit 101, system bus 102, ROM 103, RAM 104, storage (accumulation) unit 110, expansion interface unit 124, digital interface unit 125, monitor unit 162, video output unit 163, speaker unit 165, audio output unit 166, operation input unit 170, etc. in the broadcast receiving device 100 of Example 1, and detailed description thereof will be omitted.

The first tuner/demodulation unit 831 receives, via an antenna not shown, the broadcast waves of a broadcast service that uses MMT as the media transport method, and tunes (selects) to the channel of the service desired by the user under the control of the main control unit 801. Furthermore, the first tuner/demodulation unit 831 demodulates the received broadcast signal to obtain an MMT data stream, which it outputs to the MMT decoding processing unit 841. The second tuner/demodulation unit 832 receives, via an antenna not shown, the broadcast waves of a broadcast service that uses MPEG2-TS as the media transport method, and tunes (selects) to the channel of the service desired by the user under the control of the main control unit 801. Furthermore, the second tuner/demodulation unit 832 demodulates the received broadcast signal to obtain an MPEG2-TS data stream, which it outputs to the MPEG2-TS decoding processing unit 842.

The MMT decoding processing unit 841 inputs the MMT data sequence output from the first tuner/demodulation unit 831 and performs separation and decoding processes for real-time presentation elements such as a video data sequence, an audio data sequence, a superimposed text data sequence, and a subtitle data sequence based on a control signal included in the MMT data sequence. The MMT decoding processing unit 841 has functions equivalent to the separation unit 132, video decoder 141, video color gamut conversion unit 142, audio decoder 143, superimposed text decoder 144, subtitle decoder 145, subtitle synthesis unit 146, subtitle color gamut conversion unit 147, data decoder 151, cache unit 152, application control unit 153, browser unit 154, application color gamut conversion unit 155, and sound source unit 156 of the broadcast receiving device 100 of Example 1. The MMT decoding processing unit 841 is capable of performing the various processes described in Example 1. Note that the details of the various processes are the same as those described in Example 1, and therefore will not be described here.

The MPEG2-TS decoding processing unit 842 inputs the MPEG2-TS data stream output from the second tuner/demodulation unit 832 and performs processes such as separating and decoding the real-time presentation elements, such as the video data stream, audio data stream, superimposed text data stream, and subtitle data stream, based on the control signals contained in the MPEG2-TS data stream. The MPEG2-TS decoding processing unit 842 has the same functionality as the IRD (Integrated Receiver Decoder) unit of a conventional television receiver that receives broadcast waves from a broadcast service that uses MPEG2-TS as the media transport method, and detailed description thereof will be omitted.

The video synthesis unit 861 inputs the video information, subtitle information, and application information output from the MMT decoding processing unit 841 and the video information, subtitle information, and application information output from the MPEG2-TS decoding processing unit 842, and performs processing such as selection and/or superimposition as appropriate. The video synthesis unit 861 is equipped with a video RAM (not shown), and drives the monitor unit 862 and other units based on the video information input to the video RAM. Furthermore, the video synthesis unit 861 performs scaling processing, superimposition processing of EPG screen information, and other processing as necessary based on the control of the main control unit 801. The audio synthesis unit 164 inputs the audio information output from the MMT decoding processing unit 841 and the audio information output from the MPEG2-TS decoding processing unit 842, and performs processing such as selection and/or mixing as appropriate.

The LAN communication unit 821 is connected to the Internet 200 via the router device 200r, and transmits and receives data to and from each server device and other communication devices on the Internet 200. It also acquires the MMT data sequence (or a portion thereof) and MPEG2-TS data sequence (or a portion thereof) of a program transmitted via the communication line, and outputs them to the MMT decoding processing unit 841 and MPEG2-TS decoding processing unit 842 as appropriate.

[Time display on broadcast receiving device]
In the broadcast receiving device 800 of this embodiment, the current date and current time can be displayed on the EPG screen, various setting screens, etc. Information regarding the current date and current time is transmitted by MH-TOT or the like in broadcast services that employ MMT as the media transport method, and is transmitted by TOT (Time Offset Table) or the like provided in SI (Service Information) specified in the MPEG-2 system in broadcast services that employ MPEG2-TS as the media transport method. The broadcast receiving device 800 can acquire information regarding the current date and current time by referring to the MH-TOT or the TOT.

In general, when the video synthesis unit 861 primarily selects video information, etc. output from the MMT decoding processing unit 841, it can be controlled so that information relating to the current date and time obtained from the MH-TOT is superimposed on the video information, etc., and when the video synthesis unit 861 primarily selects video information, etc. output from the MPEG2-TS decoding processing unit 842, it can be controlled so that information relating to the current date and time obtained from the TOT is superimposed on the video information, etc.

However, because there are differences in encoding/decoding processes and transmission paths between broadcast services that use MMT as the media transport method and broadcast services that use MPEG2-TS as the media transport method, there is a possibility that inconsistencies may occur, particularly in the current time display, when selecting a broadcast service that uses MMT as the media transport method and a broadcast service that uses MPEG2-TS as the media transport method. For example, as shown in FIG. 25, when switching the screen display from EPG screen 162g, which displays channel information for a broadcast service that uses MMT as the media transport method, to EPG screen 162h, which displays channel information for a broadcast service that uses MPEG2-TS as the media transport method, the current time display switches from current time display 162g1 to current time display 162h1, creating an inconsistency that may cause the user to feel visually uncomfortable.

In the broadcast receiving device 800 of this embodiment, in order to prevent the user from experiencing visual discomfort, even when the video synthesis unit 861 is primarily selecting video information output from the MMT decoding processing unit 841, the device is controlled to superimpose information related to the current date and time obtained from the TOT onto the video information. In other words, the device is controlled to superimpose current time information provided by a broadcast service that uses MPEG2-TS as the media transport method onto the content of a broadcast service that uses MMT as the media transport method.

By performing the above control, the broadcast receiving device 800 of this embodiment always displays the current time information obtained by referencing the TOT when displaying the current time. Therefore, even when switching between a broadcast service that uses MMT as the media transport method and a broadcast service that uses MPEG2-TS as the media transport method, it is possible to prevent the user from feeling visually uncomfortable due to inconsistencies in the display of the current time.

FIG. 26 shows an example of the control of the selection of the current time information reference source in accordance with the reception status of each broadcast service in the broadcast receiving device 800 of this embodiment. In the broadcast receiving device 800 of this embodiment, when reception of a broadcast service that uses MPEG2-TS as the media transport method is possible, the device always references the TOT to acquire current time information, and only when reception of a broadcast service that uses MPEG2-TS as the media transport method is impossible and reception of a broadcast service that uses MMT as the media transport method is possible, the device is controlled to reference the MH-TOT to acquire current time information.

Furthermore, the same effect as described above can be achieved by controlling the content of a broadcast service that uses MMT as the media transport method to be superimposed on the current time information provided by the broadcast service that uses MPEG2-TS as the media transport method, in the opposite way to the above control.

As mentioned above, in either case, whether the current time information provided by a broadcast service that uses MPEG2-TS as the media transport method is superimposed on the content of a broadcast service that uses MMT as the media transport method, or the current time information provided by a broadcast service that uses MPEG2-TS as the media transport method is superimposed on the content of a broadcast service that uses MMT as the media transport method, the current time information can be corrected by referencing the "delta" parameter of the time information in the TMCC extension information area, as described in "Time Management of Broadcast Receiving Device" in Example 1.

[EPG display on broadcast receiving device]
Event schedule information for broadcast services that employ MMT as the media transport method is transmitted by MH-EIT, etc. On the other hand, event schedule information for broadcast services that employ MPEG2-TS as the media transport method is transmitted by EIT (Event Information Table) or the like provided in SI defined in the MPEG-2 system. Therefore, generally, when video information, etc. provided by a broadcast service that employs MMT as the media transport method is displayed, the event schedule information (MH-EIT) for the broadcast service that employs MMT can be acquired, and when video information, etc. provided by a broadcast service that employs MPEG2-TS as the media transport method is displayed, the event schedule information (EIT) for the broadcast service that employs MPEG2-TS can be acquired.

However, the broadcast receiving device 800 of this embodiment is capable of acquiring both the MH-EIT and the EIT, whether it is displaying video information provided by a broadcast service that uses MMT as the media transport method or video information provided by a broadcast service that uses MPEG2-TS as the media transport method, thereby improving usability for the user.

Figure 27A shows an example of an EPG screen in the broadcast receiving device 800 of this embodiment. In the figure, EPG screen 162i is an EPG screen created based on the MH-EIT of a broadcast service that uses MMT as the media transport method, with "M1 TV," "M2 Broadcast," "M3 Channel," "M4 TV," "Television M5," etc. being the names of broadcast stations for broadcast services that use MMT as the media transport method. Also, EPG screen 162j is an EPG screen created based on the EIT of a broadcast service that uses MPEG2-TS as the media transport method, with "T6 TV," "T7 Broadcast," "T8 Channel," "T9 TV," "Television TA," etc. being the names of broadcast stations for broadcast services that use MPEG2-TS as the media transport method.

For example, if a user operates a remote control (not shown) to display an EPG screen while watching a broadcast program provided by a broadcast service that uses MMT as the media transport method, the initial EPG screen (not shown) will be displayed. The initial EPG screen is an EPG screen created based on the MH-EIT of the broadcast service that uses MMT as the media transport method, and displays detailed information about broadcast programs on each channel from 5:00 PM on October 7, 2014 (today) (nearby the current time). Next, if the user wishes to check detailed information about broadcast programs on each channel from 8:00 PM on October 9, 2014, and operates a remote control (not shown) to update the EPG screen, EPG screen 162i will be displayed.

Furthermore, if the user wishes to check detailed information about a broadcast program provided by a broadcast service that uses MPEG2-TS as the media transport method and operates a remote control (not shown) to instruct a network switch, EPG screen 162j is displayed. In this case, the broadcast receiving device 800 of this embodiment is controlled to display detailed information about the broadcast programs on each channel on the same day and in the same time slot (i.e., from 8:00 PM on October 9, 2014) as the previously displayed EPG screen 162i, rather than the initial EPG screen (i.e., detailed information about the broadcast programs on each channel from 5:00 PM on October 7, 2014) created based on the EIT of the broadcast service that uses MPEG2-TS as the media transport method.

The above control allows the user to easily and continuously check detailed information about broadcast programs airing on the same day and at the same time on multiple networks using different media transport methods. This improves the usability of the broadcast receiving device 800.

Figure 27B shows a different example of the EPG screen in the broadcast receiving device 800 of this embodiment. EPG screen 162k shows the state in which EPG screen 162i shown in Figure 27A has been scrolled in the channel direction (horizontal direction) by operating a remote control (not shown). In other words, in the example shown in Figure 27B, by scrolling the EPG screen in the channel direction (horizontal direction), channel information created based on the MH-EIT of a broadcast service that uses MMT as the media transport method and channel information created based on the EIT of a broadcast service that uses MPEG2-TS as the media transport method are seamlessly displayed on the same timeline.

Therefore, even if a user desires to check channel information created based on the EIT of a broadcast service that uses MPEG2-TS as the media transport method while checking channel information created based on the MH-EIT of a broadcast service that uses MMT as the media transport method, it is possible to eliminate the need to issue an instruction to switch networks using a remote control (not shown). Furthermore, the user can simultaneously check detailed information about broadcast programs airing on the same day and at the same time on multiple networks that use different media transport methods. In other words, the usability of the broadcast receiving device 800 is improved.
Example 3

The following describes Example 3 of the present invention. Note that the configuration, effects, etc. of this example are the same as those of Example 1 unless otherwise specified. Therefore, the following mainly describes the differences between this example and Example 1, and explanations of common points will be omitted as much as possible to avoid duplication.

The broadcast receiving device 100 of this embodiment is capable of supporting HDR (High Dynamic Range), a technology that expands the brightness range of colors in video content, and expanded color gamuts. Furthermore, MMT, the media transport method supported by the broadcast receiving device 100 of this embodiment, is capable of transmitting content information related to HDR and expanded color gamuts along with the encoded data of the program content, enabling video reproduction as intended by the content producer on the monitor device used by the user (such as the broadcast receiving device 100 of this embodiment).

[System configuration]
The system configuration in this embodiment is basically the same as the system configuration shown in Fig. 1. The coded data of the program content included in the broadcast waves transmitted from the radio tower 300t may be the content data output from the photographing device 390c, which is appropriately subjected to coding and modulation processes, etc., and then transmitted without being temporarily stored in the broadcast station server 300, as shown in Fig. 28. Alternatively, the content data output from the photographing device 390c may be stored in the broadcast station server 300, and the stored content data may be subjected to various video/audio editing processes by the editing device 390e, and then appropriately subjected to coding and modulation processes, etc., before being transmitted.

In addition, the broadcast waves will also contain coded data and text information for the program content, other applications, general-purpose data, etc., as well as content information descriptors containing information on the luminance of the program content and the color reproduction capabilities of the equipment used to create/edit the program content (such as the camera equipment 390c and the monitor device of the editing equipment 390e), as control information (content information) related to the program content, along with the aforementioned MMT-SI messages/tables/descriptors.

[Data structure of content information descriptor]
29A shows an example of the data structure of a content information descriptor. The content information descriptor may be placed in the MPT or MH-EIT. Each parameter in the data structure of the content information descriptor has the function described below.

・'descriptor_tag (descriptor tag)'
The descriptor tag is a 16-bit field that has the function of uniquely identifying each descriptor.

・'descriptor_length (descriptor length)'
The descriptor length indicates the total number of data bytes of each parameter that follows this field.

・'component_tag (component tag)'
The component tag is a label for uniquely identifying a component stream and is described in a 16-bit field. It shall have the same value as the component tag described in the MH-stream identification descriptor.

・'content_type (content type)'
The content type indicates the type of video content included in the component stream according to FIG. 29B. When this parameter is "0," this indicates that the video content has been edited and processed by the editing device 390e (such as a recorded program). When this parameter is "1," this indicates that the video content has been edited and processed by the editing device 390e (such as a recorded program) and that this content is HDR-compatible. When this parameter is "2," this indicates that the video content is content data (such as a live broadcast program) output from the image capture device 390c. When this parameter is "3," this indicates that the video content is content data (such as a live broadcast program) output from the image capture device 390c and that this content is HDR-compatible. Furthermore, other classifications may be made using this parameter.

・“source_primaries_rx (source device primary color chromaticity coordinates (Rx))”
“source_primaries_ry (source device primary color chromaticity coordinates (Ry))”
“source_primaries_gx (source device primary color chromaticity coordinates (Gx))”
“source_primaries_gy (source device primary color chromaticity coordinates (Gy))”
“source_primaries_bx (source device primary color chromaticity coordinates (Bx))”
“source_primaries_by (source device primary color chromaticity coordinates (By))”

The source device primary chromaticity coordinates are parameters that indicate information about the color reproduction performance of the source device, and indicate the color gamut that the source device can support using coordinate values on the CIE chromaticity diagram (CIExy chromaticity diagram) for each of the primary colors R (red), G (green), and B (blue). Note that if the "content_type" parameter is "0" or "1," the source device is the monitor device of editing device 390e. In this case, the source device primary chromaticity coordinates indicate the chromaticity coordinate values of the color gamut that can be displayed on the monitor device of editing device 390e. Note that if the "content_type" parameter is "2" or "3," the source device is the imaging device 390c. In this case, the source device primary chromaticity coordinates indicate the chromaticity coordinate values of the color gamut that can be output by the imaging device 390c.

Each coordinate value on the CIE chromaticity diagram is represented by a value ranging from "0.000" to "1.000," and is described in a 10-bit field in the range of "0000000000b" to "1111101000b." For example, as shown in Figure 29C, the chromaticity coordinate values for R (red) in the BT.709 standard are "x = 0.640 (1010000000b)" and "y = 0.330 (0101001010b)," while the chromaticity coordinate values for G (green) in the BT.2020 standard are "x = 0.170 (0010101010b)" and "y = 0.797 (1100011101b)."

・"source_white_point_x (source device white chromaticity coordinate (x))"
“source_white_point_y (source device white chromaticity coordinate (y))”
The source device white chromaticity coordinates are parameters indicating information regarding the color reproduction performance, etc., of the source device, and indicate the coordinate values on the CIE chromaticity diagram of the white reference point that the source device can support. Note that if the "content_type" parameter is "0" or "1," the source device is the monitor device of the editing device 390e. In this case, the source device white chromaticity coordinates indicate the chromaticity coordinate values of the white reference point of the monitor device of the editing device 390e. Also, if the "content_type" parameter is "2" or "3," the source device is the imaging device 390c. In this case, the source device white chromaticity coordinates indicate the chromaticity coordinate values of the white reference point that the imaging device 390c can output.

Each coordinate value on the CIE chromaticity diagram is represented by a value ranging from "0.0000" to "1.0000," and is described in a 14-bit field in the range of "00000000000000b" to "10011100010000b." For example, as shown in Figure 29C, the chromaticity coordinate values of the white reference point in the BT.709 and BT.2020 standards are "x = 0.3127 (00110000110111b)" and "y = 0.3290 (00110011011010b)."

・『source_luminance_max (maximum brightness of source device)』
"source_luminance_min (source device minimum luminance)"
The source device maximum luminance and source device minimum luminance are parameters indicating information regarding the maximum and minimum luminance that the source device can support. Note that if the "content_type" parameter is "0" or "1," the source device is the monitor device of the editing device 390e. In this case, the source device maximum luminance and source device minimum luminance indicate the maximum and minimum values of luminance that can be displayed on the monitor device of the editing device 390e. Note that if the "content_type" parameter is "2" or "3," the source device is the imaging device 390c. In this case, the source device maximum luminance and source device minimum luminance indicate the maximum and minimum values of luminance that the imaging device 390c can output.

The source device maximum luminance shall be expressed as a value in the range of "1 (cd/ ^m2 : candela/square meter)" to "65535 (cd/ ^m2 )" and shall be described in a 16-bit field in the range of "0000h" to "FFFFh". The source device minimum luminance shall be expressed as a value in the range of "0.0001 (cd/ ^m2 )" to "6.5535 (cd/ ^m2 )" and shall be described in a 16-bit field in the range of "0000h" to "FFFFh".

・'num_of_scene (number of scenes)'
The number of scenes indicates the number of scenes (which may also be called chapters, etc.) that make up the video content included in the component stream. If the number of scenes is "1", this parameter may be omitted.

・"scene_start_time (scene start time)"
The scene start time is a 40-bit field that indicates the start time of a scene (chapter). The upper 16 bits of this field indicate the lower 16 bits of the Modified Julian Day (MJD), and the lower 24 bits indicate the hour, minute, and second of Japan Standard Time (JST) as a six-digit BCD code. If the number of scenes is "1", this parameter may be omitted.

・'scene_duration'
The scene duration is a 24-bit field that indicates the duration of a scene (chapter). This field indicates the duration in hours, minutes, and seconds using a six-digit BCD code. If the number of scenes is "1", this parameter may be omitted.

・'max_light_level_of_content (maximum content brightness)'
The content maximum brightness is a 16-bit field that indicates the maximum brightness within each scene (chapter). If the number of scenes is "1", this parameter indicates the maximum brightness throughout the entire content. The content maximum brightness is expressed as a value in the range of "1 (cd/ ^m2 )" to "65535 (cd/ ^m2 )", and is written in the range of "0000h" to "FFFFh" in a 16-bit field.

・'max_frame_ave_light_level (maximum frame average brightness)'
The maximum average frame luminance is a 16-bit field that indicates the maximum value of the average frame luminance within each scene ( ^chapter ). If the number of scenes is "1", this parameter indicates the maximum value of the average frame luminance throughout the entire content. The maximum average frame luminance is expressed as a value in the range of "1 (cd/m2)" to "65535 (cd/ ^m2 )", and is written in the range of "0000h" to "FFFFh" in a 16-bit field.

・'max_light_level_of_frame (maximum brightness within frame)'
The maximum luminance within a frame is expressed as a 16-bit field, and is expressed as a value in the range of 1 (cd/ ^m2 ) to 65535 (cd/ ^m2 ), and is written in the range of 0000h to FFFFh in the 16-bit field.

・'frame_average_light_level (average brightness within the frame)'
The average luminance within a frame is expressed as a 16-bit field that indicates the average luminance of each frame. The average luminance within a frame is expressed as a value in the range of "1 (cd/ ^m2 )" to "65535 (cd/ ^m2 )" and is written in the range of "0000h" to "FFFFh" in the 16-bit field.

・“EOTF_identification”
The EOTF (Electro-Optical Transfer Function) identification identifies the type of electrical-to-optical signal conversion characteristics (transfer characteristics), such as gamma correction, applied to the video signal of the video content included in the component stream. For example, in the example shown in FIG. 29D, when this parameter is "0," it indicates that the video content has undergone gamma correction suitable for a monitor device with BT.709-compliant display characteristics. When this parameter is "2," it indicates that the video content has undergone 10-bit gamma correction suitable for a monitor device with BT.2020-compliant display characteristics. When this parameter is "3," it indicates that the video content has undergone 12-bit gamma correction suitable for a monitor device with BT.2020-compliant display characteristics. When this parameter is "4," it indicates that the video content has undergone gamma correction suitable for a monitor device with SMPTE2084-compliant display characteristics. Furthermore, other classifications may be performed using this parameter. The "EOTF identification" parameter may be capable of identifying the type of colorimetry, etc. Note that the types of conversion characteristics (transfer characteristics) between electrical signals and optical signals shown in Fig. 29D are merely examples, and other conversion characteristics (transfer characteristics) between electrical signals and optical signals may be processed on the video signal of the video content, and the characteristics may be identified by the "EOTF identification" parameter.

Here, the broadcast receiving device 100, which receives video content and the "EOTF identification" parameter, references the "EOTF identification" parameter associated with the video content and also references the display characteristics of the monitor device that will display the video content, and performs appropriate electrical-to-optical conversion and other processing based on these, thereby enabling the video content to be displayed in a state suitable for the monitor device. For example, if the transfer characteristics identified by the "EOTF identification" parameter associated with the video content correspond to the display characteristics of the monitor device that will display the video content, then the electrical-to-optical conversion identified by the "EOTF identification" parameter can be performed as is in the display processing. Furthermore, if the transfer characteristics identified by the "EOTF identification" parameter associated with the video content do not correspond to the display characteristics of the monitor device that displays the video content, rather than directly performing the electrical-to-optical conversion identified by the "EOTF identification" parameter, a conversion process can be performed to convert the video signal, which has been converted between an electrical signal and an optical signal according to the identification of the "EOTF identification" parameter, into a video signal suitable for electrical-to-optical conversion corresponding to the display characteristics of the monitor device, and then a display process can be performed to perform electrical-to-optical conversion corresponding to the display characteristics of the monitor device.

The following describes the conversion process that converts the video signal, which has undergone the aforementioned electrical-to-optical conversion process according to the "EOTF identification" parameter, into a video signal suitable for electrical-to-optical conversion corresponding to the display characteristics of the monitor device. Hereinafter, this process will be referred to as transfer characteristic conversion processing.

Video content with a value of "2," "3," or "4" for the "EOTF identification" parameter is HDR video content, which has a wide range of expressible brightness and color gamut. In contrast, video content with a value of "0" for the "EOTF identification" parameter is SDR (Standard Dynamic Range) video content, which has a narrower range of expressible brightness and color gamut than HDR video content.

In addition, display devices with display characteristics compliant with BT.2020 and display devices with display characteristics compliant with SMPTE2084 can be called HDR-compatible display devices. In contrast, display devices with display characteristics compliant with BT.709 can be called SDR-compatible display devices. Furthermore, display devices with display characteristics compliant with BT.709 that do not support HDR display characteristics such as BT.2020 or SMPTE2084 can be called SDR-compatible display devices (non-HDR-compatible display devices), as a sub-concept of SDR-compatible display devices.

If the transfer characteristic conversion process is not performed when displaying the HDR video content on an SDR-compatible display device (non-HDR display device), such as a monitor device with BT.709-compliant display characteristics, the monitor device will not be able to fully represent the wide range of brightness and color gamut of the HDR video content, resulting in a hard-to-view displayed image with loss of brightness and color. In other words, in this case, the transfer characteristic conversion process simply converts the wide range of brightness and color gamut of the HDR video content so that it fits within the range of brightness and color gamut that can be represented by the monitor device. This process may also be referred to as a light-to-dark dynamic range reduction conversion or a color gamut reduction conversion. Furthermore, since this process converts HDR video content with a wide range of brightness and color gamut that can be represented into SDR video content with a narrower range of brightness and color gamut, it may also be referred to as an HDR-SDR conversion process.

On the other hand, video content with a value of "0" for the "EOTF Identification" parameter is SDR video content with a narrow range of brightness and color gamut that can be displayed. When displaying such SDR video content on an HDR-compatible display device, such as a monitor device with BT.2020-compliant display characteristics, if the transfer characteristic conversion process is not performed, the monitor device's wide brightness and color gamut display capabilities cannot be fully utilized. In other words, in this case, the transfer characteristic conversion process simply involves performing a conversion process on the SDR video content so that the monitor device's wide brightness and color gamut display capabilities can be fully utilized. This process may also be referred to as brightness dynamic range expansion conversion or color gamut expansion conversion. Furthermore, since this process converts SDR video content with a narrow range of brightness and color gamut that can be displayed into HDR video content with a wide range of brightness and color gamut, it may also be referred to as SDR-HDR conversion processing. Note that this SDR-HDR conversion process is not necessarily required, and it is not necessary to perform the SDR-HDR conversion process when displaying the SDR video content on an HDR-compatible display device, such as a monitor with BT.2020-compliant display characteristics. In this case, the brightness and color gamut display performance will remain within the range of SDR display characteristics, but there will be no problem as the displayed image will not be difficult to see due to loss of brightness or color.

In addition, if the "EOTF identification" parameter is not associated with the video content received by the broadcast receiving device 100 and cannot be acquired (if it was not originally transmitted), or if the value of the "EOTF identification" parameter associated with the video content received by the broadcast receiving device 100 cannot be acquired and determined due to a transmission error or the like, the following processing can be performed.

As a first processing example, the value of the "EOTF identification" parameter of the received video content may be treated as, for example, "2" or "3." In other words, if the value of the "EOTF identification" parameter cannot be identified, the video content can be treated as HDR video content. In this way, if the monitor device is an HDR-compatible display device such as a monitor device with display characteristics that comply with BT.2020, the transfer characteristic conversion process will not be performed, but if the actual content is HDR video content, it will be displayed appropriately. Even if the actual content is SDR video content, the brightness and color gamut display performance will remain within the range of SDR display characteristics, but the displayed image will not be difficult to see due to brightness crushing or color crushing. Furthermore, if the monitor device is BT. On an SDR-compatible display device (non-HDR display device), such as a monitor with display characteristics conforming to G.709, the video content is treated as HDR video content and the transfer characteristic conversion process is performed. However, if the actual content is HDR video content, the HDR-SDR conversion process is appropriately performed and displayed. Even if the actual content is SDR video content, the brightness and color gamut display capabilities will be more limited than the range of SDR display characteristics, but at least the displayed image will not be difficult to see due to brightness and color crush that cannot fully express the brightness and color gamut of the video content. (If SDR-HDR conversion processing is performed on HDR video content, or if HDR video content is displayed directly on an SDR-compatible display device (non-HDR display device) without HDR-SDR conversion, the displayed image may be difficult to see due to brightness and color crush. However, the first processing example avoids this situation.)

According to the first processing example described above, if the value of the "EOTF identification" parameter cannot be identified, the video content is treated as HDR video content. This enables video display with fewer problems for the user, regardless of whether the monitor device is an HDR-compatible display device or an SDR-compatible display device (non-HDR-compatible display device), or whether the actual content is HDR video content or SDR video content.

As a second example of processing when the value of the "EOTF identification" parameter cannot be obtained (including when it has not been transmitted, there is a transmission error, or the value is invalid), parameters related to the resolution of the video signal contained in the video component descriptor, etc., may be referenced to determine whether to treat the content as HDR video content or SDR video content.

For example, even if the value of the "EOTF Identification" parameter cannot be identified, if the parameter related to the resolution of the video signal indicates that the video content is high-resolution content, such as 3840 x 2160 pixels or 7680 x 4320 pixels, it may be determined to be HDR video content. Specifically, the value of the "EOTF Identification" parameter can be interpreted as "2" or "3." Since it is expected that high-resolution content of 3840 x 2160 pixels or 7680 x 4320 pixels will often be prepared and used as HDR video content in the future, this type of processing will make it more likely that the content will be displayed appropriately.

Furthermore, even if the value of the "EOTF identification" parameter cannot be identified, if the parameter related to the resolution of the video signal indicates that the video content has a resolution of 1920 x 1080 pixels or less, it may be determined to be SDR video content. Specifically, the value of the "EOTF identification" parameter can be interpreted as "0." Since there is a large amount of existing SDR content with a resolution of 1920 x 1080 pixels or less, this type of processing makes it more likely that the content will be displayed appropriately.

According to the second processing example described above, when the value of the "EOTF identification" parameter cannot be identified, the resolution-related parameters are referenced for judgment, making it more likely that an appropriate display will be produced.

Next, we will explain the processing that is performed when the value of the "EOTF identification" parameter associated with the video content received by the broadcast receiving device 100 is a value for which no relationship to display characteristics is provided in the table of FIG. 29D. Here, a value for which no relationship to display characteristics is provided in the table of FIG. 29D means that the value of the "EOTF identification" parameter in the table of FIG. 29D is a value reserved for the future, such as "1" or "5" to "15," or an unexpected value. These values may also be expressed as invalid values. In the case of such invalid values (values for which no relationship to display characteristics is provided), similar effects can be achieved by performing either the first or second processing example described above.

In the configuration diagram of Figure 7A, the various video processing operations according to the "EOTF identification" parameters described above can be performed by the video color gamut conversion unit 142, which is controlled by the main control unit 101 based on the data separated by the separation unit 132.

Here, when the video content to be displayed switches between HDR and SDR video content due to a change in program or channel, ideally the timing at which the decoded video from the video decoder 141 in Figure 7A switches between HDR and SDR video content should coincide with the timing at which the video processing by the video color gamut conversion unit 142 switches between processing for HDR and SDR video content. However, in reality, it is conceivable that there will be some degree of timing discrepancy.

In an HDR-compatible display device that performs SDR-HDR conversion processing on SDR video content, if the timing of the video processing switch by the video color gamut conversion unit 142 is earlier than the timing of the switch of the decoded video from the video decoder 141 when switching from HDR video content to SDR video content, there will be a time when the SDR-HDR conversion processing is performed on the HDR video content, potentially resulting in a display image that is difficult to see due to brightness crushing and color crushing. Therefore, when switching from HDR video content to SDR video content, the main control unit 101 can control the processing timing of the video decoder 141 and the video color gamut conversion unit 142 so that the timing of the video processing switch by the video color gamut conversion unit 142 is later than the timing of the switch of the decoded video from the video decoder 141. Alternatively, control may be performed to mute the video, such as by displaying black, before the switching between the two begins, and then to cancel the mute state, such as by displaying black, after the switching between the two is complete.

Furthermore, in an HDR-compatible display device that performs SDR-HDR conversion processing on SDR video content, if the timing at which the video color gamut conversion unit 142 switches video processing is later than the timing at which the decoded video from the video decoder 141 switches when switching from SDR video content to HDR video content, there will be a time when the SDR-HDR conversion processing is performed on the HDR video content, and there is a possibility that the displayed image will be difficult to see due to brightness crushing and color crushing. Therefore, when switching from SDR video content to HDR video content, the main control unit 101 simply controls the processing timing of the video decoder 141 and the video color gamut conversion unit 142 so that the timing at which the video color gamut conversion unit 142 switches video processing is earlier than the timing at which the decoded video from the video decoder 141 switches. Alternatively, the video may be muted (e.g., blacked out) before the switching process between the two begins, and then the video may be muted (e.g., blacked out) after the switching process is complete.

In an SDR-compatible display device that performs HDR-SDR conversion processing on HDR video content and displays SDR video content without performing transfer characteristic conversion processing, if the timing of the video processing switch by the video color gamut conversion unit 142 is earlier than the timing of the switch of the decoded video from the video decoder 141 when switching from HDR video content to SDR video content, there will be a period of time when the HDR video content is displayed on the SDR-compatible display device as is without performing transfer characteristic conversion processing, potentially resulting in a display image that is difficult to see due to brightness crushing and color crushing. Therefore, when switching from HDR video content to SDR video content, the main control unit 101 simply controls the processing timing of the video decoder 141 and the video color gamut conversion unit 142 so that the timing of the video processing switch by the video color gamut conversion unit 142 is later than the timing of the switch of the decoded video from the video decoder 141. Alternatively, the video may be muted (e.g., blacked out) before the switching process between the two begins, and then the video may be muted (e.g., blacked out) after the switching process is complete.

In an SDR-compatible display device that performs HDR-SDR conversion processing on HDR video content and displays SDR video content without performing transfer characteristic conversion processing, if the timing at which the video color gamut conversion unit 142 switches video processing is delayed compared to the timing at which the decoded video from the video decoder 141 switches when switching from SDR video content to HDR video content, there will be a period of time where the HDR video content is displayed on the SDR-compatible display device without undergoing transfer characteristic conversion processing, potentially resulting in a poorly viewable displayed image with loss of brightness and color. Therefore, when switching from SDR video content to HDR video content, the main control unit 101 simply controls the processing timing of the video decoder 141 and the video color gamut conversion unit 142 so that the timing at which the video color gamut conversion unit 142 switches video processing is earlier than the timing at which the decoded video from the video decoder 141 switches. Alternatively, the video may be muted (e.g., blacked out) before the switching process between the two begins, and then the video may be muted (e.g., blacked out) after the switching process is complete.

As explained above, by performing processing related to the timing of switching between decoded images and transfer characteristic conversion processing, it is possible to avoid presenting users with images that are difficult to see due to loss of brightness or color.

In place of, or in addition to, the identification process and various video processes using the "EOTF_identification" parameter in the content information descriptor described above, a flag that enables identification similar to the aforementioned "EOTF_identification" parameter may be inserted into the coded video stream, and the identification process and various video processes may be performed using the inserted flag. The identification process and various video processes when using the "EOTF_identification" flag as a flag in the coded video stream can be performed by referencing the "EOTF_identification" flag inserted in the coded video stream instead of referencing the "EOTF_identification" parameter in the content information descriptor described above in the description of the identification process and various video processes when using the "EOTF_identification" parameter in the content information descriptor, and therefore a detailed description will be omitted.

However, if the "EOTF_identification" flag is inserted into the encoded video stream as a flag on a frame-by-frame or GOP-by-GOP basis, for example, it becomes possible to switch between HDR and SDR video content and switch between various video processing modes corresponding to each video content in finer time increments than when using the "EOTF_identification" parameter in the content information descriptor, which is set on an asset-by-asset or program-by-program basis. In other words, the video decoder 141 can grasp the switching between HDR and SDR video content on a frame-by-frame or GOP-by-GOP basis, and the downstream video gamut conversion unit 142 can refer to the identification information for the HDR and SDR video content on a frame-by-frame or GOP-by-GOP basis. This has the effect of improving the synchronization accuracy of the timing of switching video processing in the video gamut conversion unit 142 compared to when the "EOTF_identification" parameter in the content information descriptor is used.

Furthermore, when using both the transmission of the 'EOTF_identification' flag in the coded video stream and the transmission of the 'EOTF_identification' parameter in the content information descriptor, the identification process using the 'EOTF_identification' flag in the coded video stream can be used to switch the video processing of the video color gamut conversion unit 142, and the 'EOTF_identification' parameter in the content information descriptor can be used, for example, to inform the user on a program-by-program basis whether the program is an HDR video content program or an SDR video content program when displaying the program information or in a program guide, thereby making it possible to more appropriately use the two types of identification information.

Furthermore, when using both the "EOTF_identification" flag in the coded video stream and the "EOTF_identification" parameter in the content information descriptor, the following processing can be considered when there is a mismatch between the two sets of identification information. The first processing example is to prioritize the use of the "EOTF_identification" flag in the coded video stream. This has the advantage of enabling accurate synchronization of the switching between HDR video content and SDR video content as described above with the switching timing of the corresponding video processing. The second processing example is to prioritize the use of the "EOTF_identification" parameter in the content information descriptor. This has the advantage of enabling rapid identification of the transfer characteristics, etc., without referencing the coded video stream.

The content information descriptor described above may have a data structure different from that shown in FIG. 29A. For example, it may further include parameters different from the parameters described above, or it may not include all of the parameters described above. Furthermore, the parameters may use different names. Furthermore, the parameters do not necessarily have to be described in a single descriptor, but may be described in, for example, two different descriptors. Furthermore, the parameters may be described in a descriptor and arranged in a table, or may be described directly in the table.

[EPG display on broadcast receiving device]
In the broadcast receiving device 100 of this embodiment, as in embodiment 1, by referring to the MH-EIT etc. and identifying the service ID, it is possible to obtain information such as the start time and broadcast duration of each event (broadcast program) and create an EPG screen, and the created EPG can be superimposed on video information etc. by the video synthesis unit 161 and displayed on the monitor unit 162.

Furthermore, the broadcast receiving device 100 of this embodiment may refer to the "content_type" parameter of the content information descriptor, and if the video content type of each broadcast program is "1" or "3," may display a symbol or other attribute indicating that the broadcast program is an HDR-compatible program, as shown in FIG. 30. The symbol or other attribute may be, for example, a symbol/letter indicating that the program is HDR-compatible, or a symbol 162a5 that symbolizes "HDR," meaning that the program is HDR-compatible. The symbol or other attribute may be displayed in the title area 162a2 of the detailed information 162a1. Alternatively, it may be displayed in a pop-up when the cursor is placed over the detailed information 162a1. It may also be displayed in some other manner.

Furthermore, if the content information descriptor separately includes a parameter such as "HDR_flag" that indicates whether the video content of the broadcast program is HDR-compatible, the "HDR_flag" parameter may be referenced to control whether or not to display a symbol or other attribute indicating that the broadcast program is HDR-compatible. Note that the name of the "HDR_flag" parameter is an example, and a different name may be used.

Furthermore, when all or any of the parameters such as the "source_luminance_max", "max_light_level_of_content", and "max_light_level_of_frame" of the content information descriptor exceed a predetermined value (for example, "100 (cd/ ^m2 )"), control may be performed to display a symbol or the like representing an attribute indicating that the broadcast program is an HDR-compatible program.

In addition, even if the type of video content of each broadcast program is "1" or "3" by referring to the "content_type" parameter of the content information descriptor, or even if all or any of the "source_luminance_max" parameter, "max_light_level_of_content" parameter, "max_light_level_of_frame" parameter, etc. of the content information descriptor exceed a predetermined value (for example, "100 (cd/ ^m2 )"), if the monitor unit 162 of the broadcast receiving device 100 does not support HDR, control may be performed so that the symbols/characters indicating that the program is HDR-compatible or the mark 162a5 symbolizing "HDR" that means that the program is HDR-compatible may not be displayed.

Furthermore, the broadcast receiving device 100 of this embodiment may refer to the "EOTF_identification" parameter of the content information descriptor, and if the type of gamma correction applied to the video content of each broadcast program is compatible with the display characteristics of the monitor unit 162 of the broadcast receiving device 100, may display a symbol or the like representing an attribute indicating that the broadcast program is a program that can be displayed with correct luminance expression. The symbol or the like representing the attribute may be, for example, a symbol/letter indicating that the program is a program that can be displayed with correct luminance expression, or may be a mark 162a6 that symbolizes "True Contrast," which means that the program is a program that can be displayed with correct luminance expression. Note that, as mentioned above, the type of gamma correction applied to the video content of each broadcast program is compatible with the display characteristics of the monitor unit 162 of the broadcast receiving device 100 when, for example, the "EOTF_identification" parameter for the video content is "0" and the display characteristics of the monitor unit 162 of the broadcast receiving device 100 conform to BT.709.

By displaying symbols and other attributes such as those described above in the detailed information 162a1 of the EPG screen 162a, the user can easily understand whether each broadcast program displayed on the EPG screen 162a is HDR compatible, whether the program can be displayed with the correct brightness, etc.

[Color gamut conversion process of broadcast receiving device]
In this embodiment, it is assumed that video content, which is a recorded program, has undergone video/audio editing by editing device 390e, as shown in FIG. 28 . That is, the video content provider edits and processes the video content while checking the edited content on the monitor of editing device 390e. Therefore, it is highly likely that the video content will be displayed optimally within the color reproduction capabilities of the monitor of editing device 390e. Meanwhile, the monitor unit 162 of the broadcast receiving device 100, which is the monitor used by the user to view the video content, also generally has different color reproduction capabilities depending on the manufacturer and model. In this case, if the color reproduction capabilities of the monitor of editing device 390e and the color reproduction capabilities of the monitor unit 162 of the broadcast receiving device 100 differ significantly, a problem may arise in which the video content cannot be displayed correctly as intended by the video content provider when it is displayed on the monitor unit 162 of the broadcast receiving device 100.

In other words, as mentioned above, the broadcasting system of this embodiment transmits a content information descriptor as an MMT-SI descriptor. This content information descriptor contains parameters indicating information about the color reproduction performance of the source device, including the coordinate values on the CIE chromaticity diagram of the R/G/B primary colors and the white reference point of the color gamut that the source device can support.

In addition, the broadcast receiving device 100 of this embodiment stores, in various information storage areas of the storage unit 110, the coordinate values on the CIE chromaticity diagram of each of the R/G/B primary colors and the white reference point of the color gamut that the monitor unit 162 can support as parameters indicating information regarding the color reproduction performance of the monitor unit 162. In the above situation, if the coordinates of the R/G/B primary colors and white reference point of the color gamut compatible with the source device described in the content information descriptor are R0/G0/B0 and W0, respectively, as shown in FIG. 31A, and the coordinates of the R/G/B primary colors and white reference point of the color gamut compatible with the monitor unit 162 stored in the various information storage areas of the storage unit 110 are R1/G1/B1 and W1, respectively, then the portion of the area made up of R0/G0/B0, which is the color gamut compatible with the source device, that does not overlap with the area made up of R1/G1/B1, which is the color gamut compatible with the monitor unit 162, is an area that may not be displayed correctly on the monitor unit 162.

To solve the above-mentioned problem, the broadcast receiving device 100 of this embodiment is equipped with a color gamut conversion processing function that converts the video data of the video content into video data suitable for display on the monitor unit 162 when there is a discrepancy between the color gamut supported by the source device described in the content information descriptor and the color gamut supported by the monitor unit 162 stored in the various information storage areas of the storage unit 110. The color gamut conversion function equipped in the broadcast receiving device 100 is described below.

The color gamut conversion processing function provided in the broadcast receiving device 100 of this embodiment is a function that converts the color gamut of the video data (equivalent to the area consisting of R0/G0/B0, which is the color gamut supported by the source device shown in Figure 31A) so that it is compatible with the color gamut based on the color reproduction performance of the monitor unit 162 (the area consisting of R1/G1/B1 shown in Figure 31A).

The color gamut conversion processing function provided in the broadcast receiving device 100 of this embodiment may convert the color gamut of the video data so that correct colors can be reproduced on the monitor unit 162 by referencing the coordinate values of each of the R/G/B primary colors of the color gamut that the source device can support, as described in the content information descriptor, and the coordinate values of each of the R/G/B primary colors of the color gamut that the monitor unit 162 can support, as stored in the various information storage areas of the storage unit 110.

On the line segment R0/G0 (or its neighboring area), color gamut conversion processing may be performed by referencing only the coordinate values of the R/G primary colors of the color gamut that the source device can support and the coordinate values of the R/G primary colors of the color gamut that the monitor unit 162 can support. On the line segment G0/B0 (or its neighboring area), color gamut conversion processing may be performed by referencing only the coordinate values of the G/B primary colors of the color gamut that the source device can support and the coordinate values of the G/B primary colors of the color gamut that the monitor unit 162 can support. On the line segment R0/B0 (or its neighboring area), color gamut conversion processing may be performed by referencing only the coordinate values of the R/B primary colors of the color gamut that the source device can support and the coordinate values of the R/B primary colors of the color gamut that the monitor unit 162 can support.

Alternatively, as shown in Figure 31B, the color gamut of the video data may be divided into three regions, and the color gamut conversion process may be different for each divided region. For example, in the region of the color gamut of the video data consisting of R0/G0/W0, the color gamut conversion process is performed by referencing the coordinate values of each R/G primary color and white reference point of the color gamut supported by the source device and the coordinate values of each R/G primary color and white reference point of the color gamut supported by the monitor unit 162. In the region of the color gamut of the video data consisting of G0/B0/W0, the color gamut conversion process is performed by referencing the coordinate values of each G/B primary color and white reference point of the color gamut supported by the source device and the coordinate values of each G/B primary color and white reference point of the color gamut supported by the monitor unit 162. In the area of the color gamut of the video data that is composed of R0/B0/W0, color gamut conversion processing is performed by referencing the coordinate values of each R/B primary color and white reference point of the color gamut that the source device can support and the coordinate values of each R/B primary color and white reference point of the color gamut that the monitor unit 162 can support.

Furthermore, when different color gamut conversion processes are used for each divided area, color gamut conversion may be performed on line segment R0/W0 (or its neighboring area) by referencing only the coordinate values of the R primary color and white reference point in the color gamut supported by the source device and the coordinate values of the R primary color and white reference point in the color gamut supported by the monitor unit 162. On line segment G0/W0 (or its neighboring area), color gamut conversion may be performed by referencing only the coordinate values of the G primary color and white reference point in the color gamut supported by the source device and the coordinate values of the G primary color and white reference point in the color gamut supported by the monitor unit 162. On line segment B0/W0 (or its neighboring area), color gamut conversion may be performed by referencing only the coordinate values of the B primary color and white reference point in the color gamut supported by the source device and the coordinate values of the B primary color and white reference point in the color gamut supported by the monitor unit 162.

An example of the color gamut conversion process will be described using Figure 31C. In this figure, R0, G0, and B0 are the coordinates of the R/G/B primary colors of the color gamut supported by the source device described in the content information descriptor, and have coordinate values of (R0x, R0y), (G0x, G0y), and (B0x, B0y), respectively. R1, G1, and B1 are the coordinates of the R/G/B primary colors of the color gamut supported by the monitor unit 162, which are stored in the various information storage areas of the storage unit 110, and have coordinate values of (R1x, R1y), (G1x, G1y), and (B1x, B1y), respectively. P0 is the specified color gamut data of the video content, and has coordinate values of (P0x, P0y). In this case, the color gamut data of P0 is converted to the color gamut data shown in P1 by the color gamut conversion process. Note that P1 has coordinate values of (P1x, P1y) and is calculated using the formula for the color gamut conversion process, an example of which is shown below.

<Example of calculation formula for color gamut conversion processing>
P1 = αR1 + βG1 + γB1
however,
α={(G0y-B0y)(P0x-B0x)+(B0x-G0x)(P0y-B0y)}/{(G0y-B0y)(R0x-B0x)
+(B0x-G0x)(R0y-B0y)}
β={(B0y-R0y)(P0x-B0x)+(R0x-B0x)(P0y-B0y)}/{(G0y-B0y)(R0x-B0x)
+(B0x-G0x)(R0y-B0y)}
γ=1-α-β

The above formula is an example of a case where color gamut conversion processing of all color gamut data within the color gamut of the video content is performed by referencing the coordinate values of each R/G/B primary color of the color gamut supported by the source device, as described in the content information descriptor, and the coordinate values of each R/G/B primary color of the color gamut supported by the monitor unit 162, as stored in the various information storage areas of the storage unit 110. A similar calculation is possible even if the color gamut of the video data is divided into three regions and different color gamut conversion processing is performed for each divided region (however, different parameters are referenced). Furthermore, because the above formula is a well-known formula using a barycentric coordinate system, detailed explanation of the derivation of the formula will be omitted. Furthermore, the above formula is merely an example, and the coordinate values of P1 may be calculated using a different formula.

Furthermore, if the entire color gamut of the video content is contained within the color gamut that the monitor device (broadcast receiving device 100, etc.) can support, the color gamut conversion process does not need to be performed. For example, if the color gamut of the video content is equivalent to the BT.709 color gamut shown in Figure 29C and the color gamut that the monitor device (broadcast receiving device 100, etc.) can support is equivalent to the BT.2020 color gamut, the entire BT.709 color gamut is contained within the BT.2020 color gamut, and therefore the color gamut conversion process does not need to be performed. In other words, the monitor device (broadcast receiving device 100, etc.) can display all of the color gamut data of the video content.

As described above, the color gamut conversion processing function of the broadcast receiving device 100 of this embodiment makes it possible to optimally display the video content on the monitor unit 162 of the broadcast receiving device 100, even if the color reproduction capabilities of the source device and the monitor unit 162 of the broadcast receiving device 100 differ.

[Brightness adjustment process of broadcast receiving device]
The broadcast receiving device 100 of this embodiment is assumed to have image quality adjustment items as shown in Fig. 32. Each of the image quality adjustment items can be adjusted according to the user's preference through user operation. Meanwhile, for the brightness adjustment items among the image quality adjustment items, automatic brightness adjustment may be possible by referring to the description in the content information descriptor. The automatic brightness adjustment process will be described below.

The broadcast receiving device 100 of this embodiment is capable of (1) performing automatic brightness adjustment by referencing the "source_luminance_max" and "source_luminance_min" parameters of the content information descriptor, (2) performing automatic brightness adjustment by referencing the "max_light_level_of_content" and "source_luminance_min" parameters, and (3) performing automatic adjustment by referencing only the "max_light_level_of_content" parameter.

In this embodiment, the broadcast receiving device 100 stores the maximum and minimum brightness values that can be displayed on the monitor unit 162 in the various information storage areas of the storage unit 110 as parameters indicating information related to the brightness display performance of the monitor unit 162.

The automatic brightness adjustment using method (1) is performed by referencing the 'source_luminance_max' and 'source_luminance_min' parameters described in the content information descriptor, as well as the maximum and minimum brightness values that can be displayed on the monitor unit 162, which are stored in the various information storage areas of the storage unit 110.

That is, as shown in FIG. 33A, the luminance expression range of the video content is converted so that the luminance level indicated by the "source_luminance_max" parameter roughly matches the maximum luminance level that can be displayed on the monitor unit 162, and so that the luminance level indicated by the "source_luminance_min" parameter roughly matches the minimum luminance level that can be displayed on the monitor unit 162. By converting the luminance expression range, the user can view video content on the monitor unit 162 of the broadcast receiving device 100 with the same luminance expression as the monitor device of the editing device 390e used by the content provider to edit and process the content.

The automatic brightness adjustment using method (2) is performed by referencing the "max_light_level_of_content" and "source_luminance_min" parameters described in the content information descriptor, as well as the maximum and minimum brightness values that can be displayed on the monitor unit 162, which are stored in the various information storage areas of the storage unit 110.

That is, as shown in Figure 33B, the luminance expression range of the video content is converted so that the luminance level indicated by the "max_light_level_of_content" parameter roughly matches the maximum luminance level that can be displayed on the monitor unit 162, and so that the luminance level indicated by the "source_luminance_min" parameter roughly matches the minimum luminance level that can be displayed on the monitor unit 162. By converting the luminance expression range, the user can view video content by fully utilizing the contrast performance of the monitor unit 162 of the broadcast receiving device 100.

If the content information descriptor also includes a parameter indicating the minimum luminance within each scene (chapter) (for example, "min_light_level_of_content (minimum content luminance)"), then by referencing the "min_light_level_of_content" parameter instead of the "source_luminance_min" parameter, it becomes possible to more effectively utilize the contrast capabilities of the monitor unit 162 of the broadcast receiving device 100.

Furthermore, when the "num_of_scene" parameter is not "1," the luminance expression range conversion process in method (2) above may be performed by changing the parameters referenced for each scene (chapter). In this case, it is possible to ensure suitable contrast performance on the monitor unit 162 of the broadcast receiving device 100 for each scene (chapter).

The automatic brightness adjustment in the method (3) is performed by referring to the "max_light_level_of_content" parameter described in the content information descriptor and the maximum brightness value that can be displayed on the monitor unit 162, which is stored in the various information storage areas of the storage unit 110. The minimum brightness value is based on "0 (cd/ ^m2 )." In this case, it is possible to obtain the same effect as the automatic brightness adjustment in the method (2), and furthermore, it is possible to perform conversion processing of the brightness expression range with simple calculations by referring to a small number of parameters.
In addition, the conversion process of the luminance expression range may be performed only when the ``source_luminance_max'' parameter and the ``max_light_level_of_content'' parameter described in the content information descriptor are greater than the maximum luminance value that can be displayed on the monitor unit 162 stored in the various information storage areas of the storage unit 110.

In other words, if the 'source_luminance_max' parameter or the 'max_light_level_of_content' parameter described in the content information descriptor is greater than the maximum brightness value that can be displayed on the monitor unit 162 stored in the various information storage areas of the storage unit 110, there is a possibility that brightness collapse will occur if the received video content is displayed as is on the monitor unit of the broadcast receiving device 100, but in the opposite case, there is no possibility that brightness collapse will occur.

As described above, the automatic brightness adjustment process of the broadcast receiving device 100 in this embodiment allows the user to view video content with the preferred brightness representation on the monitor unit 162 of the broadcast receiving device 100 by referencing the content information descriptor.

According to this embodiment, by referring to the content information accompanying the program content contained in the broadcast wave, it is possible to provide a more useful MMT-compatible broadcast receiving device that is capable of performing the above-mentioned processes that correspond to HDR and expanded color gamut.
Example 4

The following describes Example 4 of the present invention. Note that the configuration, effects, etc. of this example are the same as those of Example 3 unless otherwise specified. Therefore, the following mainly describes the differences between this example and Example 3, and explanations of common points will be omitted as much as possible to avoid duplication.

[System configuration]
FIG. 34 is a system configuration diagram showing an example of a broadcast communication system including a broadcast receiving device of this embodiment. The broadcast communication system of this embodiment is composed of a broadcast receiving device 40100, an antenna 40100a, a connection cable 40200, a monitor device 40300, a broadband network such as the Internet 200, a router device 200r, a broadcast station radio tower 300t, a broadcast satellite (or communication satellite) 300s, a broadcast station server 300, a service provider server 400, and other application servers 500. Although not shown, the system may further include an access point 200a, a mobile telephone communication server 600, a mobile telephone communication network base station 600b, and a portable information terminal 700, connected in the same manner as the system configuration diagram of the broadcast communication system of Example 1 (see FIG. 1). In this case, the portable information terminal 700 may be able to communicate directly with the broadcast receiving device 40100 without going through the router device 200r or the like.

Furthermore, as shown in FIG. 28, the coded data of the program content contained in the broadcast waves transmitted from the radio tower 300t may be output from the filming equipment 390c, or may be data that has undergone various video/audio editing processes by the editing equipment 390e.

The broadcast receiving device 40100 receives broadcast waves transmitted from the radio tower 300t via the broadcast satellite (or communication satellite) 300s and the antenna 40100a. Alternatively, the broadcast waves transmitted from the radio tower 300t may be received directly from the antenna 40100a without going through the broadcast satellite (or communication satellite) 300s. The broadcast receiving device 40100 can also be connected to the Internet 200 via the router device 200r, and can send and receive data via communication with various server devices and other communication devices on the Internet 200.

The connection cable 40200 is a communication cable that connects the broadcast receiving device 40100 and the monitor device 40300, and transmits encoded video/audio data, etc. output from the broadcast receiving device 40100. The monitor device 40300 is a video display device that provides the user with video information and audio information obtained by performing predetermined signal processing on the encoded video/audio data, etc. received via the connection cable 40200, via a display device such as an LCD panel and speakers.

The monitor device 40300 may also be connectable to the Internet 200 via the router device 200r, and may be capable of transmitting and receiving data via communication with each server device and other communication devices on the Internet 200. The monitor device 40300 may also be capable of receiving broadcast waves transmitted from the radio tower 300t via the antenna 40300a (not shown).

[Hardware configuration of broadcast receiving device]
35A is a block diagram showing an example of the internal configuration of a broadcast receiving device 40100. The broadcast receiving device 40100 is composed of a main control unit 101, a system bus 102, a ROM 103, a RAM 104, a storage (accumulation) unit 110, a LAN communication unit 121, an extension interface unit 124, a digital interface unit 40125, a tuner/demodulation unit 131, a separation unit 132, a video decoder 141, a video color gamut conversion unit 142, an audio decoder 143, a character superimposition decoder 144, a subtitle decoder 145, a subtitle synthesis unit 146, a subtitle color gamut conversion unit 147, a data decoder 151, a cache unit 152, an application control unit 153, a browser unit 154, an application color gamut conversion unit 155, a sound source unit 156, a video synthesis unit 161, a video output unit 163, an audio synthesis unit 164, an audio output unit 166, an operation input unit 170, and a transcode processing unit 40181.

The broadcast receiving device 40100 of this embodiment is an optical disk drive recorder such as a DVD recorder or BD recorder, a magnetic disk drive recorder such as an HDD recorder, an STB, etc. In other words, compared to the broadcast receiving device 100 of Example 1, the monitor unit 162 and speaker unit 165 may be omitted.

The digital interface unit 40125 is an interface that outputs or inputs encoded digital video data and/or digital audio data. The digital interface unit 40125 is capable of directly outputting an MMT data sequence obtained by demodulation in the tuner/demodulation unit 131, an MMT data sequence obtained via the LAN communication unit 121, or mixed data of the above MMT data sequences. It may also be controlled so that the MMT data sequence input from the digital interface unit 40125 is input to the separation unit 132.

Digital content stored in the storage unit 110 may be output or digital content may be stored in the storage unit 110 via the digital interface unit 40125. The digital interface unit 40125 may also be a DVI terminal, an HDMI (registered trademark) terminal, a DisplayPort (registered trademark) terminal, or the like, and may be controlled to output video data and audio data output from the video synthesis unit 161 and the audio synthesis unit 164 in a format compliant with the DVI specification, the HDMI specification, the DisplayPort specification, or the like.

The transcode processing unit 40181 is a signal processing unit that performs transcode calculations to convert the encoding format, bit rate, media transport method, etc. of each component that makes up the content. For example, the transcode processing unit 40181 is capable of converting an MMT data stream of broadcast program content that includes a video component in MPEG-H HEVC format output from the separation unit 132 into an MPEG2-TS data stream (or an MPEG2-PS data stream) of program content that includes a video component in MPEG-2 or MPEG-4 AVC (Advanced Video Coding) format.

It is also possible to perform processing that changes only the bit rate without changing the component encoding format or media transport method. The program content that has undergone the transcoding calculation process can be stored in the storage unit 110 as recorded content, or output from the digital interface unit 40125 or the like and supplied to an external monitor device, etc.

[Software configuration of broadcast receiving device]
35B is a software configuration diagram of the broadcast receiving device 40100 of this embodiment, and shows the software configuration in the ROM 103, RAM 104, and storage (accumulation) unit 110. Compared to the software configuration diagram of the broadcast receiving device 100 of Example 1 (see FIG. 7D), a transcoding processing program 41003 and a recording/playback processing program 41004 are added to the storage (accumulation) unit 110.

The transcoding processing program 41003 and recording/playback processing program 41004 stored in the storage unit 110 are respectively expanded in RAM 104, and the main control unit 101 executes the expanded transcoding processing program and recording/playback processing program to form a transcoding processing execution unit 41103 and a recording/playback processing execution unit 41104. The transcoding processing execution unit 41103 mainly controls the transcoding calculation processing in the transcoding processing unit 40181. The recording/playback processing execution unit 41104 mainly controls the recording processing of broadcast program content to the content storage area 1200 and the playback processing of recorded content from the content storage area 1200.

The receiving function execution unit 1102 deployed in the RAM 104 further includes an output control unit 41102i. The output control unit 41102i of the receiving function execution unit 1102 controls each process related to data output from the video output unit 163, audio output unit 166, and digital interface unit 40125.

Note that the software configuration shown in Figure 35B is merely an example, and this embodiment does not necessarily include all of the programs and execution units shown.

[Interface configuration between broadcast receiving device and monitor device]
36 is a system configuration diagram showing an example of the interface configuration between the broadcast receiving device 40100 and the monitoring device 40300. In this embodiment, a case will be described in which a connection terminal (not shown) of the digital interface unit 40125 on the broadcast receiving device 40100 side and a connection terminal of a digital interface unit (not shown) on the monitoring device 40300 side are connected by a connection cable 40200. Note that the monitoring device 40300 may have the same configuration as the broadcast receiving device 100 shown in FIG. 7A. In this case, the digital interface unit 125 corresponds to the digital interface unit on the monitoring device 40300 side described above, and the connection cable 40200 is connected to its connection terminal.

As shown in Figure 36, the connection cable 40200 is composed of n pairs of differential transmission lanes (CH1 to CHn), as well as DDC (Display Data Channel) lines, HPD (Hot Plug Detect) lines, and CEC (Consumer Electronics Control) lines standardized by the VESA (Video Electronics Standards Association). The differential transmission lanes may also be referred to as differential transmission lines.

The n pairs of differential transmission lanes may consist of one pair of clock lanes and (n-1) pairs of data lanes. For example, n = 4 and one pair of clock lanes and three pairs of data lanes may be used, or n = 2 and one pair of clock lanes and one pair of data lanes may be used. Also, all of the n pairs of differential transmission lanes may be data lanes that transmit data with a clock superimposed thereon. For example, n = 4 and four pairs of data lanes may be used. The clock lanes and data lanes may also be referred to as clock lines and data lines, respectively.

Digital video (R/G/B/Vsync/Hsync, Y/Pb(Cb)/Pr(Cr), etc.)/audio signals and other control signals may be output in a predetermined format from the video synthesis unit 161 and audio synthesis unit 164 via the transmission processing unit 40125b of the digital interface unit 40125 on the broadcast receiving device 40100 side to the data lane. The predetermined format may conform to specifications such as HDMI (registered trademark), and detailed explanations will be omitted. The digital video/audio signals and other control signals are received by the reception processing unit 40325b of the digital interface unit on the monitor device 40300 side, and undergo necessary processing such as image quality adjustment and volume adjustment as appropriate in the video processing unit and audio processing unit (not shown), before being output from the display unit and speaker of the monitor device 40300.

The connection cable 40200 may further include a power supply line, a GND line, and a backup line, although these are not shown. The n pairs of differential transmission lanes and communication lines may be shielded by a GND line. All or part of the backup line, DDC line, HPD line, and CEC line may also be used as part of the communication line for network communication. For example, the backup line and HPD line may constitute one transmission line and one reception line of the communication line, or one pair of transmission and reception lines. The CEC line, etc. may be omitted. The DDC line may be used as an I2C (I-squared-C) communication line between the main control unit 101 of the broadcast receiving device 40100 and the main control unit (not shown) of the monitor device 40300.

The transmission processing unit 40125b of the digital interface unit 40125 on the broadcast receiving device 40100 side communicates with the reception processing unit 40325b of the digital interface unit on the monitor device 40300 side via the DDC line, and is also capable of reading EDID (Extended Display Identification Data) from the EDID storage unit 40325c. In other words, by obtaining the EDID, the broadcast receiving device 40100 can determine the display capabilities of the monitor device 40300.

In this embodiment, the display performance refers to items such as the input resolution and frame rate that the monitor device 40300 can support, the video standard, whether it supports 3D video display, and whether the monitor device 40300 can process HDR or an expanded color gamut.

In addition, in this embodiment, the following explanation will be given using as an example the process of acquiring the EDID as a means for the broadcast receiving device 40100 to determine the display performance of the monitor device 40300. However, the information acquired is not limited to EDID. For example, performance identification information that identifies the display performance and functions of the monitor device 40300, which is information different from EDID, may be acquired. Furthermore, the display performance of the monitor device 40300 may be determined by means other than acquiring the performance identification information.

The transmission control unit 40125a of the digital interface unit 40125 on the broadcast receiving device 40100 side controls the transmission processing unit 40125b and is capable of detecting, via the HPD line, that the monitor device 40300 has been connected or that the monitor device 40300 has been powered on. The transmission control unit 40125a of the digital interface unit 40125 on the broadcast receiving device 40100 side is also capable of performing processes such as powering on the monitor device 40300 via the CEC line. The reception control unit 40325a of the digital interface unit on the monitor device 40300 side also controls the reception processing unit 40325b.

Note that the configuration of the connection cable 40200, the internal configuration of the digital interface unit 40125 of the broadcast receiving device 40100, and the internal configuration of the digital interface unit of the monitor device 40300 shown in Figure 36 are merely examples, and different configurations may be used.

[Mastering information parameters]
In this embodiment, as in the third embodiment, the content information descriptor shown in FIG. 29A is transmitted as control information related to the program content together with each message/table/descriptor of the MMT-SI described above. On the other hand, the broadcast receiving device 40100 of this embodiment does not include a monitor unit or speaker that ultimately provides video and audio signals to the user, but transmits encoded video/audio data, etc. to the monitor device 40300 via a connection cable 40200, and the monitor device 40300 provides the video and audio signals to the user. In other words, processing such as color gamut conversion processing and brightness adjustment processing described in the third embodiment is performed on the monitor device 40300 side according to the display performance of the display unit of the monitor device 40300.

In order to enable the above-mentioned processes on the monitor device 40300 side, the broadcast receiving device 40100 of this embodiment has the function of receiving the content information descriptor from the broadcast waves, appropriately selecting each parameter described in the received content information descriptor, and transmitting it as mastering information in a predetermined format to the monitor device 40300 via the connection cable 40200. Note that, for example, if the connection cable 40200 is an HDMI (registered trademark) cable and the video data, audio data, and other control signals output from the digital interface unit 40125 are in a format that complies with the HDMI (registered trademark) specification, the mastering information may be output as part of the other control signals.

Figure 37 shows a list of the parameters that the broadcast receiving device 40100 in this embodiment transmits to the monitoring device 40300 as mastering information.

'source_primaries_R[x,y]', 'source_primaries_G[x,y]', and 'source_primaries_B[x,y]' are parameters that indicate information regarding the color reproduction performance of the source device, and indicate the color gamut that the source device can support using coordinate values on the CIE chromaticity diagram for each primary color of R (red), G (green), and B (blue). The parameters 'source_primaries_rx', 'source_primaries_ry', 'source_primaries_gx', 'source_primaries_gy', 'source_primaries_bx', and 'source_primaries_by' described in the content information descriptor may be selected and output as the 'source_primaries_R[x,y]', 'source_primaries_G[x,y]', and 'source_primaries_B[x,y]' parameters of the mastering information.

'white_point_x,y' is a parameter indicating information about the color reproduction performance of the source device, and indicates the coordinate values on the CIE chromaticity diagram of the white reference point that the source device can support. The 'source_white_point_x' and 'source_white_point_y' parameters described in the content information descriptor may be selected and output as the 'white_point_x,y' parameters of the mastering information.

"max_source_mastering_luminance" is a parameter that indicates information about the maximum luminance that the source device can support. It is indicated by a value ranging from "1 (cd/ ^m2 : candela/square meter)" to "65535 (cd/ ^m2 )." The "source_luminance_max" parameter described in the content information descriptor may be selected and output as the "max_source_mastering_luminance" parameter of the mastering information.

"min_source_mastering_luminance" is a parameter that indicates information about the minimum luminance that the source device can support. It is indicated by a value ranging from "0.0001 (cd/ ^m2 )" to "6.5535 (cd/ ^m2 )." The "source_luminance_min" parameter described in the content information descriptor may be selected and output as the "min_source_mastering_luminance" parameter of the mastering information.

"Maximum_Content_Light_Level" is a parameter that indicates the maximum brightness within the content. It is expressed as a value ranging from "1 (cd/ ^m2 )" to "65535 (cd/ ^m2 )." The "max_light_level_of_content" parameter described in the content information descriptor may be selected and output as the "Maximum_Content_Light_Level" parameter of the mastering information.

"Maximum_Frame-average_Light_Level" is a parameter that indicates the maximum value of the average frame luminance within the content. It is indicated by a value ranging from "1 (cd/ ^m2 )" to "65535 (cd/ ^m2 )." The "max_frame_ave_light_level" parameter described in the content information descriptor may be selected and output as the "Maximum_Frame-average_Light_Level" parameter of the mastering information.

'Light Level Status' is a 2-bit flag signal that indicates the status of the 'Maximum_Content_Light_Level' parameter and the 'Maximum_Frame-average_Light_Level' parameter.

When the value of this flag is "00b," the "Maximum_Content_Light_Level" parameter and the "Maximum_Frame-average_Light_Level" parameter indicate the maximum brightness and maximum frame average brightness throughout the entire content. When the value of this flag is "01b," the "Maximum_Content_Light_Level" parameter and the "Maximum_Frame-average_Light_Level" parameter indicate the maximum brightness and maximum frame average brightness for each scene (chapter).

If the value of this flag is "10b", it indicates that the "Maximum_Content_Light_Level" parameter and the "Maximum_Frame-average_Light_Level" parameter are omitted. Instead of setting the value of this flag to "10b", the values of the "Maximum_Content_Light_Level" parameter and the "Maximum_Frame-average_Light_Level" parameter may be set to "0".

The broadcast receiving device 40100 of this embodiment transmits the above-described parameters as mastering information to the monitor device 40300 via the connection cable 40200, allowing the monitor device 40300 to perform processing such as color gamut conversion and brightness adjustment according to the display capabilities of the display unit of the monitor device 40300 on the encoded video/audio data transmitted from the broadcast receiving device 40100. Note that the parameters of the mastering information described above may further include parameters different from those shown in Figure 37, or may not include all of the above parameters. Furthermore, the parameters may use different names.

[Mastering information generation process of broadcast receiving device]
In this embodiment, if the "content_type" parameter of the content information descriptor is "2" or "3," the video content is content data (such as a live broadcast program) output from the image capture device 390c, and the content information descriptor does not have the "max_light_level_of_content" parameter and the "max_frame_ave_light_level" parameter. This is because, in a live broadcast program or the like, the maximum brightness and maximum average brightness values throughout the entire content are not determined until the end of the program content.

In this case, the broadcast receiving device 40100 of this embodiment outputs mastering information by setting the values of the "Maximum_Content_Light_Level" parameter and the "Maximum_Frame-average_Light_Level" parameter to "0". Alternatively, the "max_light_level_of_frame" parameter and the "frame_average_light_level" parameter of the content information descriptor may be used in place of the "Maximum_Content_Light_Level" parameter and the "Maximum_Frame-average_Light_Level" parameter.

On the other hand, when the video content is recorded in the content storage area 1200 of the storage unit 110, the broadcast receiving device 40100 may create the 'Maximum_Content_Light_Level' parameter and the 'Maximum_Frame-average_Light_Level' parameter. In other words, by performing the recording process for the video content, the broadcast receiving device 40100 can scan the video content from its beginning to its end, and therefore determine the maximum values of the maximum brightness and average brightness throughout the entire content.

Furthermore, when video content recorded in the content memory area 1200 of the storage unit 110 through a recording process is output from the digital interface unit 40125 via the connection cable 40200 to the monitor device 40300 through a playback process, the broadcast receiving device 40100 may scan the video content from start to finish to create the maximum brightness and maximum average brightness values for the entire content, and output them as the 'Maximum_Content_Light_Level' parameter and the 'Maximum_Frame-average_Light_Level' parameter. In other words, in the case of video content that has already been recorded, all parameters of the mastering information can be output to the monitor device 40300 regardless of the value of the 'content_type' parameter in the content information descriptor.

[Mastering information output control of broadcast receiving device]
The parameters of the mastering information described above may be constantly output to the monitor device 40300 connected via the connection cable 40200. Alternatively, the transmission processing unit 40125b of the digital interface unit 40125 on the broadcast receiving device 40100 side may refer to the EDID acquired from the EDID storage unit 40325c of the monitor device 40300, and only when it is determined that the monitor device 40300 is capable of processing compatible with HDR and an expanded color gamut may the parameters of the mastering information be output to the monitor device 40300 via the connection cable 40200. Alternatively, the parameters of the mastering information may be output to the monitor device 40300 via the connection cable 40200 only when the content information descriptor indicates that the video content of the broadcast program is compatible with HDR.

Note that the content information descriptor indicates that the video content of the broadcast program is HDR-compatible when the "content_type" parameter of the content information descriptor is "1" or "3", when the "HDR_flag" parameter of the content information descriptor indicates that the video content of the broadcast program is HDR-compatible, when all or any of the "source_luminance_max" parameter, the "max_light_level_of_content" parameter, the "max_light_level_of_frame" parameter, etc. of the content information descriptor exceed a predetermined value (e.g., "100 (cd/ ^m2 )"), etc.

The output of each parameter of the mastering information may also be controlled according to the interface type of the digital interface unit 40125. For example, if the interface type of the digital interface unit 40125 is an HDMI interface, control may be performed to output each parameter of the mastering information, and if the interface type is a DVI interface, control may be performed to not output each parameter of the mastering information.

Alternatively, the output of each parameter of the mastering information may be controlled depending on the interface type of the digital interface unit 40125 on the broadcast receiving device 40100 side and the interface type of the digital interface unit on the monitor device 40300 side. For example, if the interface type of the digital interface unit 40125 on the broadcast receiving device 40100 side and the interface type of the digital interface unit on the monitor device 40300 side are both HDMI interfaces, control may be performed to output each parameter of the mastering information. If the interface type of the digital interface unit 40125 on the broadcast receiving device 40100 side is an HDMI interface but the interface type of the digital interface unit on the monitor device 40300 side is not an HDMI interface (for example, if it is a DVI interface or DisplayPort interface, i.e., if the connection cable 40200 is an interface conversion cable), control may be performed not to output each parameter of the mastering information.

Furthermore, if the digital interface unit 40125 is composed of a first digital interface terminal and a second digital interface terminal, control may be performed so that the format of the output data differs depending on whether the data is output from the first digital interface terminal or the second digital interface terminal. In this case, each of the digital interface terminals has the configuration shown in FIG. 36 or another configuration.

For example, if the first digital interface terminal is an HDMI interface and the second digital interface is not an HDMI interface, the output data generation process and data output process can be controlled so that when data is output from the first digital interface terminal, output data including a video signal, an audio signal, and the mastering information is generated and output from the first digital interface terminal, and when data is output from the second digital interface terminal, output data including a video signal and an audio signal but not the mastering information is generated and output from the second digital interface terminal.

As described above, the broadcast receiving device 40100 of this embodiment transmits mastering information along with encoded video/audio data to the monitor device 40300, allowing the monitor device 40300 to optimally perform color gamut conversion processing, brightness adjustment processing, and the like. In other words, it is possible to provide a broadcast receiving device that can perform functions with higher added value.

The above describes examples of embodiments of the present invention using Examples 1 to 4, but the configurations that realize the technology of the present invention are not limited to the above examples, and various modifications are possible. For example, it is possible to replace part of the configuration of one example with the configuration of another example, or to add the configuration of one example to the configuration of another example. All of these fall within the scope of the present invention. Furthermore, the numerical values, messages, etc. that appear in the text and figures are merely examples, and the effects of the present invention will not be diminished even if different ones are used.

The functions of the present invention described above may be realized in part or in whole in hardware, for example by designing them as integrated circuits. They may also be realized in software, with a microprocessor unit or the like interpreting and executing an operating program that realizes each function. Hardware and software may also be used together.

The software that controls the broadcast receiving device 100 may be stored in the ROM 103 and/or storage unit 110 of the broadcast receiving device 100 before the product is shipped. It may also be acquired via the LAN communication unit 121 from another application server 500 on the Internet 200 after the product is shipped. Furthermore, the software stored on a memory card, optical disc, etc. may be acquired via the expansion interface unit 124, etc.

Furthermore, the control and information lines shown in the diagram are those considered necessary for explanation, and do not necessarily represent all control and information lines on the product. In reality, it is safe to assume that almost all components are interconnected.

100, 800, 40100... Broadcast receiving device, 100a, 40100a... Antenna, 101, 801... Main control unit, 102, 802... System bus, 103, 803... ROM, 104, 804... RAM, 110, 810... Storage unit, 121, 821... LAN communication unit, 124, 824... Expansion interface unit, 125, 825, 40125... Digital interface unit, 131, 83 1,832...tuner/demodulation unit, 132...separation unit, 141...video decoder, 142...video color gamut conversion unit, 143...audio decoder, 144...character superimposition decoder, 145...subtitle decoder, 146...subtitle synthesis unit, 147...subtitle color gamut conversion unit, 151...data decoder, 152...cache unit, 153...application control unit, 154...browser unit, 155...application color gamut conversion unit, 1 56...sound source unit, 161, 861...video synthesis unit, 162, 862...monitor unit, 163, 863...video output unit, 164, 864...audio synthesis unit, 165, 865...speaker unit, 166, 866...audio output unit, 170, 870...operation input unit, 40181...transcode processing unit, 841...MMT decode processing unit, 842...MPEG2-TS decode processing unit, 200...Internet, 200r... Router device, 200a...access point, 300t...radio tower, 300s...broadcast satellite (or communication satellite), 300...broadcast station server, 390c...filming equipment, 390e...editing equipment, 400...service provider server, 500...other application servers, 600...mobile telephone communication server, 600b...base station, 700...portable information terminal, 40200...connection cable, 40300...monitor device.

Claims (6)

A video display device that displays video based on program content received via broadcasting and/or communication,
a display unit capable of displaying video data and program information based on the program content;
a broadcast receiving unit capable of receiving program content and transfer characteristic information relating to a color gamut or luminance corresponding to the program content via broadcast;
a communication unit capable of receiving program content and transfer characteristic information relating to a color gamut or luminance corresponding to the program content via communication;
a storage unit that stores display characteristic information related to a color gamut or brightness that can be supported by the display unit that displays based on the video data of the program content received by the broadcast receiving unit and/or the communication unit;
a video conversion processing unit that performs color gamut conversion processing and luminance conversion processing on the video data of the program content received by the broadcast receiving unit and/or the communication unit based on the transfer characteristic information received by the broadcast receiving unit and/or the communication unit and the display characteristic information read from the storage unit;
a control unit that generates detailed program information to be displayed on the display unit of the video display device based on the program information, and controls the broadcast receiving unit and/or the communication unit, the storage unit, and the video conversion processing unit;
Equipped with
The transfer characteristic information received by the broadcast receiving unit and/or the communication unit includes two types of transfer characteristic information: first type transfer characteristic information indicating whether or not video data of the program content supports high dynamic range (HDR) on a program-by-program basis, and received in a state where the transfer characteristic information is not included in the video data stream of the program content; and second type transfer characteristic information indicating whether or not video data of the program content supports HDR on a program-by-program basis, and received in a state where the transfer characteristic information is included in the video data stream of the program content;
a first control state in which the control unit displays, on a program-by-program basis, a mark indicating whether or not the program content is HDR-compatible in the display of the program detail information based on the first type of transfer characteristic information;
a second control state in which the control unit controls the video conversion processing unit to perform the color gamut conversion processing and the luminance conversion processing on the video data of the program content in a unit different from a program unit, based on the second type of transfer characteristic information;
the second type of transfer characteristic information is received in a time unit that is finer than the first type of transfer characteristic information;
Video display device. 2. The image display device according to claim 1,
The color gamut conversion process in the image conversion processing unit includes:
If the color gamut indicated by the transfer characteristic information is included in the color gamut indicated by the display characteristic information, the color gamut conversion process is not performed, and if the color gamut indicated by the transfer characteristic information is not included in the color gamut indicated by the display characteristic information, the color gamut conversion process is performed so that the color gamut of the program content is included in the color gamut indicated by the display characteristic information.
Video display device. 2. The image display device according to claim 1,
The luminance conversion process in the image conversion processing unit is
When the maximum luminance that the display unit can handle, which is indicated in the display characteristic information, is not greater than the maximum luminance of the program content, which is indicated in the transfer characteristic information, the luminance conversion process is performed so that the maximum luminance of the program content becomes the luminance that can be displayed on the display unit.
Video display device. A video display device that displays video based on program content received via broadcasting and/or communication,
a display unit capable of displaying video data and program information based on the program content;
a broadcast receiving unit capable of receiving program content and transfer characteristic information relating to a color gamut or luminance corresponding to the program content via broadcasting, and/or a communication unit capable of receiving program content and transfer characteristic information relating to a color gamut or luminance corresponding to the program content via communication;
a storage unit that stores display characteristic information related to a color gamut or brightness that can be supported by the display unit that displays based on the video data of the program content received by the broadcast receiving unit and/or the communication unit;
a video conversion processing unit that performs color gamut conversion processing and luminance conversion processing on the video data of the program content received by the broadcast receiving unit and/or the communication unit based on the transfer characteristic information received by the broadcast receiving unit and/or the communication unit and the display characteristic information read from the storage unit;
a control unit that generates detailed program information to be displayed on the display unit of the video display device based on the program information, and controls the broadcast receiving unit and/or the communication unit, the storage unit, and the video conversion processing unit;
Equipped with
The transfer characteristic information received by the broadcast receiving unit and/or the communication unit includes two types of transfer characteristic information: first type transfer characteristic information indicating whether or not video data of the program content supports high dynamic range (HDR) on a program-by-program basis, and received in a state where the transfer characteristic information is not included in the video data stream of the program content; and second type transfer characteristic information indicating whether or not video data of the program content supports HDR on a program-by-program basis, and received in a state where the transfer characteristic information is included in the video data stream of the program content;
a first control state in which the control unit displays, on a program-by-program basis, a mark indicating whether or not the program content is HDR-compatible in the display of the program detail information based on the first type of transfer characteristic information;
a second control state in which the control unit controls the video conversion processing unit to perform the color gamut conversion processing and the luminance conversion processing on the video data of the program content in a unit different from a program unit, based on the second type of transfer characteristic information;
the second type of transfer characteristic information is received in a time unit that is finer than the first type of transfer characteristic information;
Video display device. 5. The image display device according to claim 4,
The color gamut conversion process in the image conversion processing unit includes:
If the color gamut indicated by the transfer characteristic information is included in the color gamut indicated by the display characteristic information, the color gamut conversion process is not performed, and if the color gamut indicated by the transfer characteristic information is not included in the color gamut indicated by the display characteristic information, the color gamut conversion process is performed so that the color gamut of the program content is included in the color gamut indicated by the display characteristic information.
Video display device. 5. The image display device according to claim 4,
The luminance conversion process in the image conversion processing unit is
When the maximum luminance that the display unit can handle, which is indicated in the display characteristic information, is not greater than the maximum luminance of the program content, which is indicated in the transfer characteristic information, the luminance conversion process is performed so that the maximum luminance of the program content becomes the luminance that can be displayed on the display unit.
Video display device.