JP7587006B2 - Content protection processing method - Google Patents

Description

The present invention relates to a content protection processing method.

One of the extension functions 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.

JP 2001-186486 A

In response to recent changes in the content distribution environment, television receivers are also being asked to expand their functions in various ways. In particular, there are many demands for the distribution of content and linked applications using broadband network environments such as the Internet, and for higher resolution and definition video content. However, it is difficult to provide high-added-value television receivers that can meet these demands by simply reusing the data broadcasting reception function and other functions that are equipped in current television receivers, or by simply expanding the functions of said data broadcasting reception function and other functions.

The object of the present invention is to realize a content protection processing method that can execute functions with higher added value.

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

By using the technology of the present invention, it is possible to realize a content protection processing method that can execute functions with higher added value.

1 is a system configuration diagram showing 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 configuration diagram of an MPU in MMT. FIG. 1 is a diagram illustrating the structure of an MMTP packet in MMT. A conceptual diagram of a protocol stack of a broadcasting system using MMT. FIG. 2 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. 2 is a configuration diagram of a logical plane structure of a presentation function of the broadcast receiving device according to the first embodiment. FIG. 1 is a system configuration diagram of clock synchronization/presentation synchronization of a broadcast receiving device according to a first embodiment. 2 is a software configuration diagram of the broadcast receiving device according to the first embodiment. FIG. FIG. 2 is a block diagram of a broadcasting station server according to the first embodiment. FIG. 2 is a block diagram of a service provider server according to the first embodiment. FIG. 2 is a block diagram of a portable information terminal according to the 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 a broadcasting system. A diagram showing the format of the JST_time parameter of a broadcasting system. 11 is a diagram showing a method of calculating the current date from the MJD of the broadcast receiving device in Example 1. A diagram showing the configuration of the NTP format of a broadcasting system. A diagram showing the data structure of an MPU timestamp descriptor in 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 the TLV-NIT of a broadcasting system. A diagram showing the data structure of a satellite distribution system descriptor of a broadcasting system. A diagram showing the data structure of a service list descriptor for a broadcasting system. A diagram showing the data structure of AMT of a broadcasting system. 4 is a sequence diagram of an operation of the broadcast receiving device according to the first embodiment when selecting a channel. 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. 13 shows an example of assignment of layouts to layout numbers based on the LCT. FIG. 13 shows an example of assignment of layouts to layout numbers based on the LCT. FIG. 13 shows an example of assignment of layouts to layout numbers based on the LCT. FIG. 13 shows an example of assignment of layouts to layout numbers based on the LCT. 11A and 11B are diagrams illustrating the operation of exception handling in screen layout control based on an LCT. 11A and 11B are diagrams illustrating the operation of exception handling in screen layout control based on an LCT. A diagram showing the data structure of MH-EIT of a broadcasting system. 3 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 3 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 3 is a screen display diagram of an EPG screen of the broadcast receiving device according to the first embodiment. FIG. 4 is a screen display diagram of the broadcast receiving device according to the first embodiment when an emergency alert broadcast is displayed. FIG. FIG. 11 is a block diagram of a broadcast receiving device according to a second embodiment. 11A and 11B are diagrams illustrating inconsistencies in the current time display when switching broadcast services. 13A and 13B are diagrams illustrating the operation of current time information reference source selection control according to the second embodiment. FIG. 11 is an operation sequence diagram of a current time information update process according to the second embodiment. FIG. 11 is a screen display diagram of an EPG screen of a broadcast receiving device according to a second embodiment. FIG. 11 is a screen display diagram of an EPG screen of a broadcast receiving device according to a second embodiment. FIG. 2 is a diagram showing the structure of program data. FIG. 2 is a structural diagram of asset data. A diagram showing the data structure of a PA message. A diagram showing the data structure of MMT_general_location_info. FIG. 2 is a diagram showing the data structure of a PLT. FIG. 13 is a diagram illustrating the meaning of location types. A diagram showing the data structure of an MPU presentation area designation descriptor. 13A to 13C are diagrams illustrating a presentation operation according to a third embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a third embodiment. A diagram showing the data structure of an LCT expiration descriptor. FIG. 13 is a diagram illustrating the data structure of a layout validity period descriptor. 13 is a diagram showing the data structure of a presentation area expiration date descriptor. 13 is a diagram showing the data structure of a common presentation area information descriptor. A diagram showing the meaning of full_set_flag. 13 is a diagram showing the data structure of an overlapping presentation area designation descriptor. 13A to 13C are diagrams illustrating a presentation operation according to a third embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a third embodiment. FIG. 13 is a diagram illustrating the data structure of a dependency descriptor. 13A to 13C are diagrams illustrating a presentation operation according to a third embodiment. FIG. 13 is a diagram illustrating a data structure of a modified example of a dependency descriptor. FIG. 13 is a diagram showing the meaning of dependency_type. 13A to 13C are diagrams illustrating a presentation operation according to a third embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a fourth embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a fourth embodiment. FIG. 13 is a diagram showing the data structure of a content control descriptor. FIG. 13 is a diagram showing the meaning of content control modes. 13A to 13C are diagrams illustrating a presentation operation according to a fourth embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a fourth embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a fourth embodiment. 13A to 13C are diagrams illustrating a presentation operation according to a fourth embodiment. A diagram showing a protocol stack of the MPEG2-TS standard. A diagram showing the data structure of a timestamp offset descriptor. FIG. 13 is a diagram for explaining a method for processing time information according to a fifth embodiment. A diagram showing the data structure of an MPU timestamp descriptor. A diagram showing the data structure of an asset presentation area designation descriptor. A diagram showing the data structure of an asset timestamp descriptor.

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, an antenna 100a, a broadband network such as the Internet 200, a router device 200r, an access point 200a, a radio tower 300t of a broadcast station, a broadcast satellite (or a communication satellite) 300s, a broadcast station server 300, a service provider server 400, other application servers 500, a mobile telephone communication server 600, a base station 600b of a mobile telephone communication network, and a mobile information terminal 700.

The broadcast receiving device 100 receives broadcast waves transmitted from a radio tower 300t via a broadcast satellite (or communication satellite) 300s and an antenna 100a. Alternatively, the broadcast waves transmitted from the radio tower 300t may be received directly from the antenna 100a without passing through the broadcast satellite (or communication satellite) 300s. The broadcast receiving device 100 can also be connected to the Internet 200 via a router device 200r, and can transmit and receive data by communicating with each server device and other communication devices on the Internet 200.

The router device 200r is connected to the Internet 200 via wired communication, 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 devices 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 be performed directly using a method such as BlueTooth (registered trademark) or NFC (Near Field Communication) without going through the router device 200r.

The radio tower 300t is a broadcasting facility of a broadcasting station, and transmits broadcast waves including encoded data and subtitle information of broadcast programs, other applications, general-purpose data, etc. The broadcasting satellite (or communication satellite) 300s is a repeater that receives broadcast waves transmitted from the radio tower 300t of the broadcasting station, performs appropriate frequency conversion, etc., and then retransmits the broadcast waves to the antenna 100a connected to the broadcast receiving device 100. The broadcasting station is also assumed to have a broadcasting station server 300. The broadcasting station server 300 stores broadcast programs (video content, etc.) and metadata such as the program title, program ID, program summary, performer information, broadcast date and time of each broadcast program, and is capable of providing the video content and each metadata to a service provider based on a contract. The video content and each metadata may be provided to the service provider through an API (Application Programming Interface) provided by the broadcasting station server 300.

The service provider server 400 is a server device prepared by a service provider, and is capable of providing various services linked to broadcast programs distributed by a broadcast station. 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 a 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. A plurality of service provider servers 400 may be prepared for each different service. The functions of the service provider server 400 may also be provided by the broadcast station server 300.

The other application server 500 is a known server device that stores, manages, and distributes other general applications, operating programs, content, data, etc. There may be multiple other application servers 500 on the Internet 200.

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

The mobile information terminal 700 has a function of telephone communication (calls) and data transmission/reception via a mobile telephone communication network, and a function of wireless communication by Wi-Fi (registered trademark) or the like. The mobile information terminal 700 can be connected to the Internet 200 via the router device 200r or the access point 200a, or via the base station 600b of the mobile telephone communication network and the mobile telephone communication server 600, and can transmit and receive data by communication with each server device on the Internet 200 and other communication devices. The access point 200a is connected to the Internet 200 by wired communication, and is connected to the mobile information terminal 700 by wireless communication. The wireless communication may be a method such as Wi-Fi (registered trademark). The 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]
The broadcast receiving device 100 shown in Fig. 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 adopted in conventional digital broadcasting systems as a media transport method for transmitting data such as video and audio. The television receiver may 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. As 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, there are limitations to the functionality of MPEG2-TS in dealing with changes in the content distribution environment, such as the recent diversification of content, the diversification of devices that use content, the diversification of transmission paths for distributing content, and the diversification of content storage environments. As a result, MMT is a newly formulated media transport method.

Figure 2A shows an example of an outline of the encoded signal in the MMT of this embodiment. As shown in the figure, the MMT of this embodiment has an MFU (Media Fragment Unit), an MPU (Media Processing Unit), an MMTP (MMT Protocol) payload, and an MMTP packet as elements constituting the encoded signal. The MFU is a format for transmitting video, audio, etc., and may be configured in NAL (Network Abstraction Layer) unit units or access unit units. The MPU may be configured with MPU metadata including information on the configuration of the entire MPU, movie fragment metadata including information on 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. In addition, in the case of media such as video components and audio components, the presentation time and the decoding time may be specified in MPU units or access unit units. Figure 2B shows an example of the configuration of an MPU.

The MMTP packet is composed of a header section and an MMTP payload, and transmits control information of the MFU and MMT. The MMTP payload has a payload header according to the contents (data units) to be stored in the payload section. FIG. 2C shows an example of an overview of constructing an MFU from a video/audio signal, storing it in the MMTP payload, and constructing an MMTP packet. In addition, for a video signal that is encoded using inter-frame prediction, it is desirable to configure the MPU in GOP (Group Of Pictures) units. In addition, when 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. In addition, when 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 by each of the above methods is in the format of MFU or MPU, and is further loaded on the MMTP payload to be packetized as MMTP packets and transmitted in IP (Internet Protocol) packets. In addition, data content related to the broadcast program may also be in the format of MFU or MPU, and further loaded on the MMTP payload to be packetized as MMTP packets 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 data transmission asynchronous with broadcasting; an event message transmission method used for synchronous/asynchronous message notification to applications running on television receivers; and a general-purpose data transmission method for synchronous/asynchronous transmission of other general-purpose data.

For the transmission of 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. In addition, 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.

In the broadcasting system of this embodiment, a mechanism is provided 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 in the form of an MMT control message, placed on 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 correspondence information between IP addresses and services.

In addition, in broadcasting systems using MMT, time information is also transmitted to provide absolute time. Note that 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]
In the broadcasting system supported by the broadcasting receiving device 100 of this embodiment, as described above, TLV-SI related to the TLV multiplexing method for multiplexing IP packets and MMT-SI related to MMT, which is a media transport method, are prepared as control information. TLV-SI provides information for the broadcasting receiving device 100 to demultiplex IP packets multiplexed on a broadcast transmission path. TLV-SI is composed of a "table" and a "descriptor". The "table" is transmitted in a section format, and the "descriptor" is placed in the "table". MMT-SI is transmission control information indicating the configuration of an MMT package and information related to a broadcasting service. MMT-SI is composed of three hierarchical layers: a "message" that stores a "table" or a "descriptor", a "table" that has elements and attributes that indicate specific information, and a "descriptor" that indicates more detailed information. An example of the hierarchical structure of control information used in the broadcasting system of this embodiment is shown in FIG. 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 are used as the "tables" of the TLV-SI.

(1) TLV-NIT
A Network Information Table for TLV (TLV-NIT) represents information on the physical configuration of the TLV stream transmitted by the 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 constitute each service transmitted in the network.

(3) Tables Set by Service Providers In addition, service providers and the like can prepare tables that they 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 the 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 etc. may prepare their own unique 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 are used as "messages" of 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>
6B shows a list of "tables" used in the 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 according to the table. In this embodiment, the following is used as the "table" of MMT-SI.

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

(2) PLT
A package list table (PLT) indicates a list of IP data flows and packet IDs that transmit PA messages of MMT packages provided as broadcast services, and IP data flows that transmit 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. The LCT may be stored in the 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)
A 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
A Download Control Message (DCM) transmits key-related information including a key for decrypting a transmission line encryption for downloading. The DCM may be stored in an M2 section message.

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

(9) MH-EIT
The MH-Event Information Table (MH-EIT) is time-series information regarding 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 their required activation states, etc. The MH-AIT may be stored in the M2 section message.

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

(13) MH-SDT
The MH-Service Description Table (MH-SDT) has a sub-table that indicates services included in a specific TLV stream, and information about the channel, such as the name of the channel and the name of the broadcasting company. 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 to be stored in a non-volatile memory in a section format for all receivers that receive the data. - The CDT may be stored in the M2 section message.

(16) DDM Table The Data Directory Management Table (DDM table) provides a directory structure of files that configure 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 MPUs in an 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 contents 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. The EMT 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. The descriptor is control information that provides more detailed information, and is arranged in a table. The table in which the descriptor is arranged may be determined according to the descriptor. In this embodiment, the following are used as "descriptors" of 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 Specification Descriptor The MPU presentation area specification descriptor provides a position for presenting the MPU. The MPU presentation area specification 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 dependent asset. The dependency descriptor may be placed in the MPT.

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

(8) Scrambling Scheme Descriptor The scrambling scheme descriptor provides information for identifying the encryption target and the type of encryption algorithm at the time of scrambling. The scrambling scheme descriptor may be placed in the MPT or CAT (MH).

(9) Message Authentication Scheme Descriptor The message authentication scheme descriptor provides information for identifying a 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. The emergency information descriptor (MH) 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 the coding method specific settings. 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 located 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 the events. 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 an event name and a short description of the event in a text format. 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 a character 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 refer to the description contents indicated by the video component descriptor in the MH-EIT by 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 an 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 viewing restrictions based on age and to extend to other restriction conditions. The MH-Parental Rating Descriptor may be placed in the MPT or 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 a character 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 constitute 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 located in the MH-BIT.

(27) MH-Broadcaster Name Descriptor The MH-Broadcaster Name Descriptor describes the name of a 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 a channel and its operator together with the service 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 Invocation Descriptor The MH-CA invocation descriptor describes invocation information for invoking a CAS program on the CAS platform. The MH-CA invocation 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 a certain offset value is to be given between the actual time (e.g., UTC+9 hours) and the display time for the human system during daylight saving time implementation. 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 in 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 the 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 depending 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 described 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 described to set an application boundary and to set authority of broadcast resource access for each area (URL). The MH-application boundary authority setting descriptor may be placed in the MH-AIT.

(48) MH-Launching Priority Information Descriptor The MH-Launching Priority Information Descriptor is described to specify the startup priority of an application. The MH-Launching Priority Information Descriptor may be placed in the MH-AIT.

(49) MH-cache information descriptor The MH-cache information descriptor is described for use in cache control when the resources constituting an application are cached and held 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 another presentation unit 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 arranged 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 arranged in the DCC table.

(54) Descriptors Set by Service Providers In addition, service providers and the like may prepare their own unique 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. The TLV stream includes TLV-SI such as TLV-NIT and AMT, and an IP data flow, which is a data flow of IP packets. The IP data flow includes video assets including a series of video MPUs and audio assets including a series of audio MPUs. Similarly, the IP data flow may include subtitle assets including a series of subtitle MPUs, superimposition assets including a series of superimposition MPUs, and data assets including a series of data MPUs. These various assets are associated in units called "packages" by the MPT (MMT package table) stored in and transmitted in a PA message. Specifically, the association is made by recording in the MPT a package ID (corresponding to the "MMT_package_id_byte" parameter shown in FIG. 17, described below) and the asset IDs of each asset included in the package (corresponding to the "asset_id_byte" parameter shown in FIG. 17, described below).

The assets constituting the package can be only assets in the TLV stream, but as shown in Figure 6E, they can also include assets transmitted in 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 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 in the broadcast MPEG2-TS (location_type = 0x03)
(5) Data multiplexed in the 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 FIG. 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. Also, (2), (3), (5), and (6) 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 having 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 FIG. 24 described later, when referring to data multiplexed into the 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.

The data constituting a "package" is specified in this manner, but in the broadcasting system to which the broadcast receiving device 100 of this embodiment corresponds, a series of data in units of this "package" is treated as a "service" unit for digital broadcasting.

Furthermore, the MPT describes the presentation time information of each MPU specified by the MPT (corresponding to the "mpu_presentation_time" parameter shown in FIG. 13B described below), and using this presentation time information, it becomes possible to present (display, output, etc.) multiple MPUs specified by the MPT in a linked manner based on a clock based on the NTP, which is time information in UTC notation. Presentation control of various data using the clock based on the NTP will be described later.

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

[Hardware configuration of broadcast receiving device]
7A is a block diagram showing an example of the internal configuration of the broadcast receiving device 100. The 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 text 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 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 according to 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 operation programs such as an operating system and other operation programs, and may be a rewritable ROM such as an EEPROM (Electrically Erasable Programmable ROM) or a flash ROM. Operation setting values required for the operation of the broadcast receiving device 100 may be stored in ROM 103. RAM (Random Access Memory) 104 serves as a work area when the basic operation programs and other operation programs are executed. ROM 103 and RAM 104 may be integrated with the main control unit 101. ROM 103 may not be an independent configuration as shown in FIG. 7A, but may use a portion of the storage area in the storage unit 110.

The storage (accumulation) unit 110 stores the operation program and operation setting values of the broadcast receiving device 100, personal information of the user of the broadcast receiving device 100, etc. It can also store operation programs downloaded via the Internet 200 and various data created by the operation programs. It can also store content such as videos, still images, and audio acquired 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. The storage (accumulation) unit 110 must retain the stored information even when power is not being supplied from an external source to the broadcast receiving device 100. Therefore, for example, devices such as non-volatile semiconductor element memories such as flash ROM and SSD (Solid State Drive), and magnetic disk drives such as HDD (Hard Disc Drive) are used.

The operating programs stored in the ROM 103 and the storage unit 110 can be added to, updated, and have their functions expanded by downloading them from each server device 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 part of it) of a program transmitted via a communication line. The connection to the router device 200r may be a wired connection or a wireless connection such as Wi-Fi (registered trademark). The LAN communication unit 121 includes an encoding circuit, a decoding circuit, and the like. The broadcast receiving device 100 may further include other communication units such as a BlueTooth (registered trademark) communication unit, an NFC communication unit, an infrared communication unit, and the like.

The tuner/demodulator 131 receives broadcast waves transmitted from the radio tower 300t via the antenna 100a, and tunes (selects) 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 string. Note that while the example shown in FIG. 7A illustrates a configuration with one tuner/demodulator, the broadcast receiving device 100 may be configured to include multiple tuner/demodulators for purposes such as simultaneous display of multiple screens and recording of other programs.

The separation unit 132 is an MMT decoder, and distributes the real-time presentation elements such as a video data string, an audio data string, a text superimposed data string, and a subtitle data string to the video decoder 141, the audio decoder 143, the text superimposed data string, and the subtitle decoder 145, based on the control signal in the input MMT data string. The data input to the separation unit 132 may be an MMT data string transmitted via a broadcast transmission path and demodulated by the tuner/demodulation unit 131, or an MMT data string transmitted via a communication line and received by the LAN communication unit 121. The separation unit 132 also plays back a multimedia application and file-based data that is a component of the application, and temporarily stores the data in the cache unit 152. The separation unit 132 also extracts generic data and outputs it to the data decoder 151 for use in streaming data for a player that presents data other than video, audio, and subtitles, or data for an application. In addition, the separation unit 132 may perform error correction and access restriction control on the input MMT data sequence based on the control of the main control unit 101.

The video decoder 141 decodes the video data string 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 string input from the separation unit 132 and outputs the audio information. In addition, the video decoder 141 and the audio decoder 143 may be input with streaming data in, for example, MPEG-DASH (MPEG-Dynamic Adaptive Streaming over HTTP) format acquired from the Internet 200 via the LAN communication unit 121. In addition, a plurality of video decoders 141, video color gamut conversion units 142, audio decoders 143, etc. may be provided in order to simultaneously decode and process a plurality of types of video data strings and audio data strings.

The character superimposition decoder 144 decodes the character superimposition data string input from the separation unit 132 and outputs character superimposition information. The subtitle decoder 145 decodes the subtitle data string input from the separation unit 132 and outputs subtitle information. The character superimposition information output from the character superimposition decoder 144 and the subtitle information output from the subtitle decoder 145 are subjected to synthesis processing in the subtitle synthesis unit 146, and further, in the subtitle color gamut conversion unit 147, color space conversion processing is performed as necessary for video synthesis processing in the video synthesis unit 161. Note that in this embodiment, among 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 the rest are referred to as character superimposition. Furthermore, when there is no distinction between them, they are collectively referred to as subtitles.

The browser unit 154 presents the multimedia application file and its component file data acquired from the server device on the Internet 200 via the cache unit 152 or the LAN communication unit 121 in accordance with the instructions of the application control unit 153, which interprets the control information included in the MMT data string and the control information acquired from the server device on the Internet 200 via the LAN communication unit 121. The multimedia application file may be an HTML (Hyper Text Markup Language) document or a BML (Broadcast Markup Language) document, 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. In addition, based on 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 MH-EIT included in MMT-SI, as necessary. The monitor unit 162 is, for example, a display device such as a liquid crystal 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 of this embodiment is provided with a logical plane structure in order to display the multimedia service as intended by the provider. FIG. 7B shows an example of the configuration of the logical plane structure provided by the presentation function of the broadcast receiving device 100 of this embodiment. In the logical plane structure, a character superimposition plane for displaying character superimposition is arranged in the foreground, and a subtitle plane for displaying subtitles is arranged in the next layer. A multimedia plane for displaying broadcast video, multimedia applications, or their composite video is arranged in the third layer, and a background plane is arranged in the background. The subtitle synthesis unit 146 and the video synthesis unit 161 draw character superimposition information on the character superimposition plane, subtitle information on the subtitle plane, and video information, application information, and the like 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 assumed that multiple third-layer multimedia planes can be prepared according to 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 voice synthesis unit 164 inputs the voice information output from the voice decoder 143 and the application voice information reproduced by the sound source unit 156, and performs processing such as selection and/or mixing as appropriate. The speaker unit 165 provides the voice information selected and/or mixed by the voice synthesis unit 164 to the user of the broadcast receiving device 100. The voice output unit 166 is an audio output interface that outputs the voice information selected and/or mixed by the voice synthesis unit 164.

The expansion interface unit 124 is a group of interfaces for expanding the functions 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 the MMT data string obtained by demodulation in the tuner/demodulator unit 131, the MMT data string obtained via the LAN communication unit 121, or mixed data of the above-mentioned MMT data strings. In addition, the digital interface unit 125 may control the MMT data string input to the separator unit 132. The output of digital content stored in the storage unit 110, or the storage of digital content in the storage unit 110 may be performed via the digital interface unit 125.

The digital interface unit 125 may be a DVI terminal, an HDMI (registered trademark) terminal, a Display Port (registered trademark) terminal, etc., and may output or input data in a format conforming to the DVI specification, the HDMI specification, the Display Port specification, etc. It may output or input data in the form of serial data conforming to the IEEE 1394 specification, etc. It may also be configured as an IP interface that outputs digital interfaces 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 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 them may be used. 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, when 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. In addition, the broadcast receiving device 100 may be a television receiver, an optical disk drive recorder such as a DVD (Digital Versatile Disc) recorder, a magnetic disk drive recorder such as a HDD recorder, a STB (Set Top Box), etc. It may also be a PC (Personal Computer), a tablet terminal, a navigation device, a game console, etc. equipped with a digital broadcast receiving function or a broadcast communication linkage function. When the broadcast receiving device 100 is a DVD recorder, a HDD recorder, a STB, etc., the monitor unit 162 and the speaker unit 165 may not be provided. 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 achieve the same operation as the broadcast receiving device 100 of this embodiment.

[System configuration of clock synchronization/presentation synchronization of broadcast receiving device]
FIG. 7C is an example of a system configuration of clock synchronization/presentation synchronization in a broadcasting system that the broadcast receiving device 100 of this embodiment supports. In the broadcasting system of this embodiment, UTC is transmitted from the broadcast sending system to the receiver (such as the broadcast receiving device 100 of this embodiment) in a 64-bit NTP timestamp format. In the NTP timestamp format, "seconds or more" of UTC are represented by 32 bits, and "less than a second" is represented by 32 bits. However, in reality, it is difficult to reproduce one second with 32-bit accuracy. For this reason, as a system clock for synchronizing a video system or a system clock for operating an NTP format clock, for example, a frequency of "2 to the 24th power" Hz (approximately 16.8 MHz) as shown in the figure may be used. In addition, considering that the system clock in the conventional broadcasting system was 27 MHz and that the hardware configuration of the receiver can be easily constructed, it is desirable to adopt a frequency of a power of 2, such as "2 to the 24th power" to "2 to the 28th power", as the system clock.

When the system clock is set to a power of 2 frequency, such as 2 to the 24th power or 2 to the 28th power, on the broadcast transmission system or receiver side, the lowest 8 to 4 bits in 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 for regenerating the system clock or the 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 FIG. 7C), the lowest 32-n bits in the NTP timestamp format may be fixed to 0 or 1. Alternatively, the receiver side may process the lowest 32-n bits in the NTP timestamp format to be ignored.

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

On the receiver side, the time information in NTP long format is received via the broadcast transmission path, and the receiving system clock is regenerated by a PLL system based on a VCO of "2 to the power of n" Hz, just like on the broadcast transmission system side. This makes the receiving system clock a clock synchronized with the broadcast transmission system side. In addition, by operating the signal processing system of the receiver in synchronization with the system clock of "2 to the power of n" Hz, clock synchronization between the broadcast transmission system side and the receiver side is realized, enabling stable signal reproduction. In addition, 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 time information in the NTP format. Here, the MPT stored in the PA message transmitted by the broadcast signal stores the MPU timestamp descriptor shown in FIG. 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 refer to the MPU timestamp descriptor stored in the MPT and control the presentation (display, output, etc.) timing of each MPU, such as the video signal, audio signal, subtitles, and superimposed text.

When focusing on the control of the decoding timing and presentation timing for each presentation unit of the aforementioned video/audio signals, etc., 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 clock of 2 to the power of m Hz 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, and shows the software configuration in the ROM 103, the RAM 104, and the 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 for accessing an external mobile terminal device or each server device, and various information storage areas for storing various other information.

The basic operation program 1001 stored in ROM 103 is expanded in RAM 104, and the main control unit 101 executes the expanded basic operation program to form a basic operation execution unit 1101. Similarly, the reception function program 1002 stored in the storage unit 110 is expanded in RAM 104, and the main control unit 101 executes the expanded reception function program to form a reception function execution unit 1102. The RAM 104 also has a temporary storage area for temporarily holding data created when each operation program is executed, as necessary.

In the following, for simplicity, the process in which the main control unit 101 controls each operation block by expanding the basic operation program 1001 stored in the ROM 103 into the RAM 104 and executing it 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 operation block of the broadcast receiving device 100 to play components such as video and audio transmitted in the broadcasting system of this embodiment. In particular, the transport processing unit 1102a mainly controls the MMT decoder function of the separation unit 132, and distributes the video data string and audio data string separated from the MMT data string to the corresponding decoding processing units. The AV decoding processing unit 1102b mainly controls the video decoder 141 and audio decoder 143. The application processing unit 1102c mainly controls the cache unit 152, application control unit 153, browser unit 154, and sound source unit 156. The character superimposition processing unit 1102d mainly controls the character superimposition decoder 144. The subtitle processing unit 1102e mainly controls the subtitle decoder 145. The general-purpose data processing unit 1102f mainly controls the data decoder 151. The EPG generation unit 1102g interprets the description contents of the MH-EIT and the like included in the MMT-SI to generate an EPG screen. The presentation processing unit 1102h mainly controls the video color gamut conversion unit 142, the subtitle synthesis unit 146, the subtitle color gamut conversion unit 147, the application color gamut conversion unit 155, the video synthesis unit 161, and the audio synthesis unit 164 based on the logical plane structure.

The operating programs may be stored in the ROM 103 and/or the storage unit 110 beforehand at the time of product shipment. After product shipment, they may be acquired via the LAN communication unit 121 from other application servers 500 on the Internet 200. In addition, the operating programs stored on a memory card, optical disk, etc. may be acquired via the expansion interface unit 124, etc.

[Broadcast station server configuration]
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, etc., of each broadcast program broadcast by a broadcast station. The metadata storage area 3300 stores metadata, such as the program title, program ID, program summary, cast, broadcast date and time, and copy control information related to each program content, of each broadcast program.

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 in the 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 ease of explanation, the process in which the main control unit 301 expands the basic operation program 3001 stored in the storage unit 310 into the RAM 304 and executes 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 each 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 each metadata of each broadcast program to the service provider based on a contract. Furthermore, when providing the program content and each metadata of each broadcast program to the service provider, the broadcast content management/distribution execution unit 3102 may perform authentication processing of the service provider server 400 based on the contract as necessary.

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

The LAN communication unit 321 is connected to the Internet 200 and communicates with the service provider server 400 on the Internet 200. The LAN communication unit 321 includes an encoding circuit, a decoding circuit, and the like. The digital broadcast signal sending unit 360 modulates an MMT data sequence consisting of video data sequences, audio data sequences, program information data sequences, and the like, of the program contents of each broadcast program stored in the broadcast content storage area 3200, and sends it out as a digital broadcast wave via the 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 composed 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 operation program. The system bus 402 is a data communication path for transmitting and receiving data between the main control unit 401 and each operation block within the service provider server 400. The RAM 404 serves as a work area when each operation 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 the program content of the broadcast program provided by the broadcast station server 300 as video content. It also stores the video content and the like produced by the service provider. The metadata storage area 4300 stores each metadata provided by the broadcast station server 300 and metadata related to the video content produced by the service provider. The application storage area 4400 stores various applications and the like for realizing services linked to the broadcast program for distribution 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 permitted to access the service provider server 400.

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 in the 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 ease of explanation, the process in which the main control unit 401 expands the basic operation program 4001 stored in the storage unit 410 into the RAM 404 and executes 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 contents and metadata of broadcast programs from the broadcast station server 300, manages the video contents and metadata stored in the video content storage area 4200 and the metadata storage area 4300, and controls the distribution of the video contents and metadata to each television receiver. Furthermore, when distributing the video contents and metadata to each television receiver, the video content management/distribution execution unit 4102 may perform authentication processing of each television receiver as necessary. Furthermore, the application management/distribution execution unit 4104 manages each application stored in the application storage area 4400 and controls the distribution of each application in response to a request from each television receiver. Furthermore, when distributing the application to each television receiver, the application management/distribution execution unit 4104 may perform authentication processing of each television receiver as necessary.

The LAN communication unit 421 is connected to the Internet 200, and communicates with the broadcast station server 300 on the Internet 200 and 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 a memory in which basic operation programs such as an operating system and other operation programs are stored, and may be a rewritable ROM such as an EEPROM or flash ROM. RAM 704 serves as a work area when the basic operation programs and other operation programs are executed. ROM 703 and RAM 704 may be integrated with the main control unit 701. Also, ROM 703 may not be an independent configuration as shown in FIG. 10A, but may use a portion of the memory area in the storage unit 710.

The storage unit 710 stores the operation program and operation setting values of the mobile information terminal 700, personal information of the user of the mobile information terminal 700, etc. It can also store operation programs downloaded via the Internet 200 and various data created by the operation programs. It can also store content such as videos, 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 stored information even when the mobile information terminal 700 is not receiving power from an external source. Therefore, for example, devices such as non-volatile semiconductor element memories such as flash ROM and SSDs, and magnetic disk drives such as HDDs are used.

The operating programs stored in the ROM 703 and the storage unit 710 can be added to, updated, and have their functions expanded by downloading 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 made via a wireless connection such as Wi-Fi (registered trademark). The mobile telephone network communication unit 722 performs telephone communication (calls) and data transmission and reception through wireless communication with the base station 600b of the mobile telephone communication network. The NFC communication unit 723 performs wireless communication when in close proximity to a corresponding reader/writer. The LAN communication unit 721, the mobile telephone network communication unit 722, and the NFC communication unit 723 are assumed to 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 functions of the portable 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 signals/audio signals from external video/audio output devices, outputs video signals/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 devices. 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 that inputs 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 them may be used. The mobile information terminal 700 may be operated using a keyboard or the like connected to the extended interface unit 724. The mobile information terminal 700 may be operated using a separate terminal device connected by 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 in 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, for example, a display device such as a liquid crystal panel, and provides the 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 the image data input to the video RAM. In addition, the image signal processing unit 742 has a function of performing format conversion, superimposition processing of menus and other OSD (On Screen Display) signals, etc. as necessary. The first image input unit 743 and the second image input unit 744 are camera units that input image data of the surroundings or object by converting light input from a 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 brightness of the surroundings, the proximity of surrounding objects, and the like. The mobile information terminal 700 may also be equipped with other sensors, such as an air pressure sensor.

The portable information terminal 700 may be a mobile phone, a smartphone, a tablet terminal, or the like. 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 shooting video, a portable game machine, a navigation device, or other portable digital device.

The example configuration of the mobile information terminal 700 shown in FIG. 10A includes many components that are not essential to this embodiment, such as the sensor unit 760, but the effect of this embodiment is not diminished even if these components are not included in the configuration. In addition, components not shown, such as a digital broadcast receiving function and an electronic money payment function, may be added.

[Software configuration of mobile information terminal]
10B is a software configuration diagram of the portable information terminal 700 of this embodiment, and shows the software configuration in the ROM 703, the RAM 704, and the 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 for storing content such as moving images, still images, and audio, an authentication information storage area 7300 for storing authentication information and the like required when accessing a television receiver or each server device, and various information storage areas for storing various other information.

The basic operation program 7001 stored in the ROM 703 is expanded in the RAM 704, and the main control unit 701 executes the expanded basic operation program to constitute a basic operation execution unit 7101. Similarly, the cooperative control program 7002 stored in the storage unit 710 is expanded in the RAM 704, and the main control unit 701 executes the expanded cooperative control program to constitute a cooperative control execution unit 7102. The RAM 704 also includes a temporary storage area for temporarily storing data created when each operation program is executed, as necessary.

In the following, for simplicity, the process in which the main control unit 701 loads the basic operation program 7001 stored in the ROM 703 into the RAM 704 and executes 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, and the like, 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 the ROM 703 and/or the storage unit 710 beforehand at the time of product shipment. After product shipment, they may be acquired from other application servers 500 on the Internet 200 via the LAN communication unit 721 or the mobile telephone network communication unit 722. In addition, the operating programs stored in a memory card, optical disk, etc. may be 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 with reference to Fig. 7C. The second time management function is a time management function based on MH-TOT, in which time is managed based on the time information transmitted by MH-TOT, as explained with reference to Fig. 6B.

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

In contrast, the information transmitted by MH-TOT is as follows. It is assumed that the broadcast receiving device 100 is capable of acquiring the current date and Japan Standard Time from MH-TOT. An example of the data structure of MH-TOT is shown in FIG. 11A. The broadcast receiving device 100 is capable of acquiring the current date and current time from the "JST_time" parameter of the MH-TOT. As shown in FIG. 11B, the "JST_time" parameter is assumed to include the lower 16 bits of the coded data of the current date based on the Modified Julian Date (MJD) and 24 bits of information that represents 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 are: two 4-bit binary coded decimal numbers represent the hour in two decimal digits, the next two 4-bit binary coded decimal numbers represent the minutes in two decimal digits, and the last two 4-bit binary coded decimal numbers represent the seconds in two decimal digits.

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

The broadcast receiving device 100 of this embodiment can achieve more accurate synchronization processing by using 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 are the content of the broadcast signal. Furthermore, by referring to information in UTC notation rather than the clock notation of the broadcast station, it is also possible to perform synchronization processing for the decoding and display of the video, audio, subtitles, superimposed text, or other data that are the content of the broadcast signal received by the broadcast signal and the video, audio, subtitles, superimposed text, or other data obtained via the communication line path.

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

The program guide generation process, the control of recording and viewing reservations, and copyright management processes such as temporary storage are also functions that are installed in receivers of digital broadcasting systems using the conventional MPEG2-TS format. In this embodiment, if the broadcasting system is configured to handle the program guide generation process, the control of recording and viewing reservations, and copyright management processes such as temporary storage 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 conventional MPEG2-TS format digital broadcast reception function and the MMT format digital broadcast reception function, it will no longer be necessary to design separate processing algorithms for these processes (program guide generation process, recording and viewing reservation control, copyright management processes such as temporary storage, etc.), which can reduce costs.

In addition, even if a receiver does not have the ability to receive digital broadcasts using the conventional MPEG2-TS format, and only has the ability to receive digital broadcasts using the MMT format, it is possible to develop the receiver at lower cost by using the algorithms of functions that are also installed in receivers for digital broadcast systems using 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.

Therefore, by configuring 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 will be possible to provide MMT digital broadcast receiving devices at a lower cost by improving compatibility with conventional broadcasting systems.

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

Therefore, by providing 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 with reference to FIG. 7C, information regarding an expected delay time in the transmission of 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, the information on the expected delay time may be configured to be transmitted not in the TLV multiplexed stream shown in FIG. 3A, but in a TMCC (Transmission and Multiplexing Configuration Control) area outside the TLV multiplexed stream. If the information is transmitted in the TMCC area, the broadcast receiving device 100 can extract the information on the expected delay time without undergoing a separation process (demux process) of the TLV multiplexed stream. In other words, it is possible to obtain information that is less susceptible to the delay caused by the separation process in the broadcast receiving device 100, and therefore it is possible to perform a highly accurate system clock correction process. An example of the data structure of the time information transmitted by the TMCC signal is described with reference to FIG. 13C. The time information may be stored in the TMCC extension information area and transmitted, for example. In the time information in the TMCC extension information area of FIG. 13C, the "delta" parameter represents the expected value of the 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. The upper 16 bits describe the integer part, and the lower 16 bits describe the decimal part. 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 part.

In the first modified example, the broadcast receiving device 100 of this embodiment can correct the system clock of the NTP-based time management function used for synchronizing each content data of the broadcast signal with higher accuracy by using information about the expected delay time described in the time information stored in the TMCC extension information area and transmitted (for example, the aforementioned "delta" parameter and/or "transmit_timestamp" parameter).

[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 by MH-TOT and manages the time. The current date and Japan Standard Time acquired from information transmitted by 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 FIG. 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, so an overflow occurs at "April 22, 2038", and dates after "April 23, 2038" cannot be expressed using the specified calculation alone. Therefore, in the second variant of this embodiment, the calculation method is switched between when the MJD value is equal to or greater than a specified value and when it is less than the specified value, so that dates after "April 23, 2038" can 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 to calculate the current date when the MJD is less than "32768". Note that the case where the MJD is less than "32768" is equivalent to the case where the most significant bit of the 16-bit data of the MJD is "0". This makes it possible for the broadcast receiving device 100 of this embodiment to express dates after "April 23, 2038". However, the predetermined value can be set arbitrarily, and the predetermined value may be set to "16384 (0x4000)" or "49152 (0xC000)", etc. The condition for switching the calculation method may be when the most significant 2 bits of the 16-bit data of the MJD are "00" or when the most significant 2 bits of the 16-bit data of the MJD are not "11." If the above-mentioned means is used with the predetermined value set to "32768," it will not be possible to express dates prior to "September 4, 1948," but this will not be a problem in practical use as a television receiver.

In addition, instead of switching between the first and second calculation methods depending on the comparison result between the MJD and the predetermined value, the first and second calculation methods may be switched depending on a flag that replaces part or all of the "reserved" parameter in the data structure of the MH-TOT shown in FIG. 11A or a newly added flag. For example, when 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, and set to "0" if the MJD does not indicate "April 23, 2038" or later. Then, when the flag is "1", the second calculation method shown in FIG. 12 may be used, and when 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.

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

Therefore, in the broadcast receiving device 100 of this embodiment, the "reference_timestamp" parameter, the "transmit_timestamp" parameter, or the "mpu_presentation_time" parameter, etc. may be referenced, and either the first calculation method or the second calculation method may be selected 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, etc.

Either way, the broadcast receiving device 100 of this embodiment can express 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 of 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 identification. Also, an address mask can be used to efficiently describe consecutive IP addresses.

In the broadcast receiving device 100 of this embodiment, when scanning channels for initial settings or when rescanning to change settings, it is possible to store a list of services acquired from the TLV-NIT in non-volatile memory such as the ROM 103 or the storage unit 110, and further, it is possible to store a list of IP multicast groups corresponding to each of the services as IP-related information in the non-volatile memory in association with each of the services. By storing the list of services and the IP-related information in non-volatile memory and making them available for constant reference, it becomes unnecessary to re-acquire the TLV-NIT or AMT when switching channels, etc., and it becomes possible to acquire broadcast content efficiently.

Figure 14 shows an example of an 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 process of S103 is valid data (S104: Yes), the reception function execution unit 1102 acquires information such as the TLV stream ID and the original network ID from the acquired TLV-NIT (S105). FIG. 15A shows an example of the data structure of the 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). FIG. 15B shows an example of the data structure of the satellite distribution system descriptor. FIG. 15C shows an example of the data structure of the service list descriptor. If the TLV-NIT has multiple different data such as the TLV stream ID, the original network ID, the distribution system information, and the list of service IDs, the processes of S105 to S107 are repeated. Next, the reception function execution unit 1102 creates a service list based on the data acquired in the processes of S105 to S107, such as the TLV stream ID, the original network ID, the distribution system information, and the list of service IDs, and stores the created service list in the ROM 103 or the storage unit 110 (updates 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 related to each service ID stored in the service list (S110). FIG. 15D shows an example of the data structure of the AMT. If the AMT has a list of IP multicast groups related to multiple service IDs, the process of S110 is repeated. If there are multiple AMTs that have lists of IP multicast groups related to 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 the storage unit 110, etc. (updates it when rescanning) (S111).

Note that if the tuner/demodulator unit 131 does not succeed in locking onto the set frequency value in the process of S102 (S102: No), and 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, if the frequency value set in the tuner/demodulator 131 is the final frequency value of the channel scan range (S112: Yes), the reception function execution unit 1102 ends the process. On the other hand, if the frequency value set is not the final frequency value of the channel scan range (S112: No), the frequency value set in the tuner/demodulator 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 having a list of IP multicast groups related to the service IDs can be acquired, the processes of S112 to S113 are not necessary.

By performing the above-mentioned 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 further stores this information in non-volatile memory such as the 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 referring to the "version_number" parameter of the TLV-NIT or AMT. When a change in the "version_number" parameter of either the TLV-NIT or AMT is detected, only the information about the table in which the change in the parameter was detected may be automatically updated. However, when the automatic update described above is performed, it is desirable to notify the user that a rescan has been performed automatically. Also, the user may be notified that a change has been made to the information in the table, and the user may be allowed to select 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 a channel) in the broadcast receiving device 100 of this embodiment.

When the user operates a remote control (not shown) to instruct channel switching, 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 starts acquiring the AMT from the signal received by the tuner/demodulator unit 131. If the AMT is successfully acquired within a predetermined time (S202: Yes), information on 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 on a list of IP multicast groups corresponding to the service ID is acquired (S204) by referring to IP-related information stored in the ROM 103 or storage unit 110 (S203). Note that the judgment process of S202 may not be performed and the IP-related information stored in the ROM 103 or storage unit 110 may always be referred to.

Next, the reception function execution unit 1102 starts acquiring the TLV-NIT from the received signal of the tuner/demodulator unit 131. If the TLV-NIT is successfully acquired within a predetermined 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 predetermined time (S205: No), the distribution system information for acquiring the IP data flow corresponding to the service ID is acquired (S207) by referring to the service list stored in the ROM 103 or the storage unit 110, etc. (S206). Note that it is also possible to always refer to the service list stored in the ROM 103 or the storage unit 110, etc. without performing the judgment process of S205. After acquiring the distribution system information in the process 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 with a packet ID of "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 refers to the "MMT_package_id_byte" parameter of the acquired MPT, and checks whether the lowest 16 bits of the "MMT_package_id_byte" parameter are the same value as the service ID. In the example of the data structure of the MPT shown in FIG. 17, if the lowest 16 bits of the "MMT_package_id_byte" parameter are 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 that contains data of the program corresponding to the service ID, and the 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), it is determined that the MMTP packet with the packet ID of "0" is not an MMTP packet having data of a program corresponding to the service ID. In this case, the transport processing unit 1102a acquires the PLT again (S212) and confirms the packet ID (assumed to be x) of the MMTP packet transmitting the MPT having the "MMT_package_id_byte" parameter corresponding to the service ID by checking the acquired PLT (S213). Furthermore, the transport processing unit 1102a acquires an MMTP packet with a packet ID of "x" from the input MMT data string (S214) and acquires the MPT included in the acquired MMTP packet (S215). Furthermore, it acquires the MFU based on the information contained in the acquired MPT (S216).

It is also possible to always perform steps S212 to S215 without performing steps S209 to S211. In this case, it is possible to reduce the processing time when data for a program 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 process of S216, the transport processing unit 1102a extracts the encoded video data, encoded audio data, etc. from the acquired MFU and outputs them to the video decoder 141, the audio decoder 143, etc. Below, video/audio decoding processing based on the control of the AV decoding processing unit 1102b and presentation processing based on the control of the presentation processing unit 1102h are performed, but since each of the above 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 with reference to FIG. 14 and FIG. 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 a non-volatile memory such as the ROM 103 or the storage unit 110 so that they can be referenced at all times, and when selecting a channel (switching a channel), the service list and IP-related information stored in the non-volatile memory such as the ROM 103 or the storage unit 110 are referenced, thereby improving the efficiency of operations during channel selection (switching a channel). In other words, it is possible to shorten the time from the start of channel selection (switching a channel) to the end of channel selection (switching a channel) compared to the case where AMT or TLV-NIT is reacquired during channel selection (switching a channel).

[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 pixels in the horizontal direction, 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 pixels in the vertical direction, 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.

Examples of layout assignment to layout numbers based on the settings of each of the above parameters are shown in Figures 19A to 19D, along with the setting values of each of the above parameters.

Figure 19A shows the default layout setting of the broadcast receiving device 100 of this embodiment, and is an example in which only one area is set on the entire screen. Figure 19B shows an example in which the entire screen is divided into three areas, each of which is designated as "Area 0", "Area 1", and "Area 2". For example, if the number of pixels on the entire screen is 7680 pixels horizontally and 4320 pixels vertically, "Area 0" is set to the range (0,0)-(6143,3455) since 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 is an example of setting three regions, similar to Figure 19B, but "region 0" is set in the range of (0,0)-(7679,4319), and "region 1" and "region 2" are placed in front of "region 0" in the same range as above, according to the setting of the "layer_order" parameter. Figure 19D is an example of the case where "region 0" is set in device 0 (default device: in this example, broadcast receiving device 100), and "region 1" is set in device 1 (in this example, mobile information terminal 700).

As mentioned above, in the broadcasting system of this embodiment, by using LCT, it becomes possible to perform screen layout control to display multimedia services 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 off (or rounding down to the nearest whole number in binary numbers) is also acceptable. For example, if the number of pixels on the entire screen is 7680 pixels/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 in the range of (0,0)-(3916,2203) by rounding up, or in the range of (0,0)-(3915,2202) by rounding down. Also, taking into account the macroblocks during video compression processing, rounding up/down processing may be performed in 8 pixel units or 16 pixel units. This processing makes it possible to efficiently perform area setting based on the LCT and resolution conversion processing 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 if the screen layout area control is performed by the above-mentioned LCT, when 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 exception process. Figure 20A shows an example of the operation of exception process of screen layout control based on the LCT.

When the same screen layout control as in FIG. 19B is performed according to the description in the LCT, and broadcast program video is displayed in "Area 0", and broadcast content such as program linkage 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 FIG. 19A is being performed) regardless of the contents of the description in the LCT, as shown in FIG. 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 according to the description in the LCT is re-executed.

By performing the above-mentioned 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 FIG. 20A (B).

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

In the case of the recording setting screen shown in FIG. 1A, the display area of the broadcast content is changed from the entire screen to only the sub-screen portion at the bottom right of the screen. Similarly, in the case of the dual-screen display shown in FIG. 1B, the display area of the broadcast content is changed from the entire screen to only the split screen portion at the left middle section 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 the area control of the screen layout within the display area (i.e., dividing the area to display 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 the broadcast content in "Area 1" or "Area 2" depending on the immediately preceding area selection situation.

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

[EPG display on broadcast receiving device]
In the broadcasting system of this embodiment, time-series information on events (so-called programs) included in each service constituting the broadcasting network is transmitted by 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 the own TLV stream and schedule information of each event of the own TLV stream. The broadcast receiving device 100 of this embodiment is capable of acquiring information such as the start time and broadcast time of each event by identifying the event by a service ID (corresponding to the "service_id" parameter in the figure) with reference to the MH-EIT, etc., and creating an EPG screen, and is capable of superimposing the created EPG on video information, etc. by the video synthesis unit 161 and displaying it on the monitor unit 162.

Figure 22A is a diagram showing an example of an EPG screen in the broadcast receiving device 100 of this embodiment. The EPG screen 162a is in a matrix shape with the vertical axis indicating time and the horizontal axis indicating service ID (channel), and displays detailed information about broadcast programs broadcast on each channel during each time period. In addition, the detailed information 162a1 of each broadcast program is mainly 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 and the like representing the attributes of the broadcast program. The symbols and the like representing the attributes of the broadcast program are, for example, symbols/characters indicating that it is a new program, or symbols/characters indicating that it is a rebroadcast program, etc. Alternatively, it may be a symbolized mark of "data", which means that it supports data broadcasting by a broadcasting service. It may also be a symbolized mark 162a4 of "Network", which means that content, applications, etc. related to the broadcast program can be obtained from a network. Furthermore, the symbols and the like representing the attributes of the broadcast program may be replaced by differentiating the background color of the detailed information 162a1 from others, or by surrounding the display area of the detailed information 162a1 with a thick frame.

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 each server device on the network is not possible, the mark 162a4 symbolizing "Network" etc. may be controlled not to be displayed.

In addition, when the broadcast program is a distributed program distributed via the Internet 200 and cannot be acquired only from the broadcast waves, and further, as described above, when the broadcast receiving device 100 is in a state where it cannot access each server device 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 substituted 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 in a state where it cannot access each server device 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 the user with 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 broadcast station names for each channel, and in particular, the "M2 Broadcast" station simultaneously provides broadcast programs distributed by 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, when the broadcast receiving device 100 is in a state where it cannot 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 make it possible for 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 performing receiving processing of an emergency alert broadcast when the emergency alert broadcast start 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 text information of the superimposed text, regardless of the state of the broadcast receiving device 100 immediately before receiving the emergency alert broadcast. That is, as shown in FIG. 23, when a user is watching a normal broadcast program and an emergency alert broadcast is received while a program screen 162e of the broadcast program is displayed on the monitor unit 162, the text information 162e1 of the emergency alert broadcast is superimposed on the program screen 162e. Similarly, when a user instructs the display of an EPG screen and an emergency alert broadcast is received while an EPG screen 162f is displayed on the monitor unit 162, the text information 162f1 of the emergency alert broadcast is superimposed on the EPG screen 162f.

By the above-mentioned control, in the broadcast receiving device 100 of this embodiment, even if the user selects and displays an EPG screen, various setting screens, a recorded program list screen, an Internet browser, etc., when an emergency alert broadcast is received, it is possible to avoid missing important text information based on the emergency alert broadcast. Note that this control may also be performed on text information of normal text superimpositions that are not based on emergency alert broadcasts.

[Various exception handling]
If the broadcast receiving device 100 of this embodiment cannot obtain data outside the TLV stream in the same package, it may perform exception processing, for example, as described below.

As described in FIG. 6E, in the broadcasting system supported by the broadcast receiving device 100 of this embodiment, the data acquired in the TLV stream and the data acquired via a route 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 FIG. 17). However, the data transmission route other than the TLV stream indicated by the location information (e.g., IPv4 data flow, IPv6 data flow, broadcast MPEG2-TS, etc.) is a receiving function separate from the receiving function of the TLV/MMT stream. Therefore, even when the broadcast receiving device 100 is operating, there may be a situation in which data cannot be acquired from these transmission routes, such as a situation in which the receiving function of these transmission routes is not operating, a situation in which the receiving function itself is operating but a relay device or the like is not operating, a situation in which these transmission routes are not connected by wire or wirelessly, or a situation in which the broadcast receiving device 100 is installed in an environment in which these transmission routes 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 acquired within the TLV stream and data acquired 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, in the case where the LCT sets multiple regions in the screen as shown in FIG. 19B or FIG. 19C, and the video contained in the TLV stream is displayed in "region 0", and data acquired through a transmission path other than the TLV stream is displayed in "region 1" or "region 2", and data from a transmission path other than the TLV stream to be displayed in "region 1" or "region 2" cannot be acquired, the layout display of the multiple regions specified by the LCT may be prohibited. Specifically, even if the LCT is received, the video of the content received in the TLV stream may be left displayed in "region 0" of the default layout display shown in FIG. 19A, and the layout display of the multiple regions may not be changed to that of FIG. 19B or FIG. 19C. Furthermore, even if an instruction to change the default layout to the layout indicated by the LCT is input to the operation input unit 170 of FIG. 7A in this state, the default layout display shown in FIG. 19A may be left as it is, or the display may be switched to another data broadcasting screen, so that the layout display of the multiple regions may not be changed to that of FIG. 19B or FIG. 19C.

As shown in Fig. 19B and Fig. 19C, when the LCT sets multiple regions within the screen, and the video contained in the TLV stream is displayed in "region 0", and data acquired via a transmission path other than the TLV stream is displayed in "region 1" and "region 2", and data of a transmission path other than the TLV stream to be displayed in "region 1" and "region 2" cannot be acquired, another example of operation when the display frame of the multiple regions shown in Fig. 19B and Fig. 19C indicated by the LCT is displayed once, and a background color or a specified still image is displayed in "region 1" and "region 2". If data of a transmission path other than the TLV stream indicated by the location information of the MPT cannot be acquired even after a specified time has elapsed, the display may be switched back to the default layout display state shown in Fig. 19A. In this case, it is preferable to operate so that the program video contained in the TLV stream continues to be displayed in "region 0" even when the layout of Fig. 19A, Fig. 19B, and Fig. 19C is changed, since the user's program video itself will continue.

In addition, when the video of the content received in the TLV stream is displayed in "Area 0" of the default layout display shown in FIG. 19A due to the inability to obtain data of a transmission path other than the TLV stream to be displayed in "Area 1" or "Area 2", the operation of various communication functions and various reception functions of the broadcast receiving device 100 of this embodiment may start, 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 in which data of a transmission path other than the TLV stream to be displayed in "Area 1" or "Area 2" can be obtained. In this case, the broadcast receiving device 100 of this embodiment may immediately switch from the default layout display shown in FIG. 19A to a layout of multiple areas as shown in FIG. 19B or FIG. 19C indicated by the LCT, and may display the video of the content received in the TLV stream in "Area 0", and switch to display data obtained from a transmission path 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 the digital broadcasting system compatible with the broadcast receiving device 100 of this embodiment, by including copy control information in the MPT and transmitting it, the copy control information may be configured to transmit, for example, "unlimited copying allowed" (which may be divided into two types: "unlimited copying allowed and encryption processing required when storing and outputting" and "unlimited copying allowed and encryption processing not required when storing and outputting"), "one generation only allowed", "predetermined number of times of copying allowed" (for example, so-called "dubbing 10" if nine times of copying and one time of moving allowed), "copy prohibited", etc. of the content referred to by the MPT. 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, etc., according to the copy control information. Note that the target of the storage process may include not only the storage (storage) unit 110 inside the broadcast receiving device 100, but also records that have been subjected to protection processing such as encryption processing so that they can be played back only by 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 the copy control information are described below.

First, when the copy control information included in the MPT indicates "unlimited copying", 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 restrictions. However, when "unlimited copying and encryption processing required at the time of storage and output" is separated from "unlimited copying and no encryption processing required at the time of storage and output", in the case of "unlimited copying and encryption processing required at the time of 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 must be performed in all cases.

In addition, if the copy control information included in the MPT indicates "copyable for one generation only," the broadcast receiving device 100 of this embodiment allows for encryption and storage in the storage (accumulation) 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, so-called move processing to an external device (processing in which content is copied to an external device and the content in the storage (accumulation) unit 110 of the broadcast receiving device 100 is made unplayable by erasing the content, etc.) is possible.

In addition, if the copy control information included in the MPT indicates that copying is permitted a specified number of times, the broadcast receiving device 100 of this embodiment allows the content to be encrypted and stored in the storage (accumulation) 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, a predetermined number of copies and move processes may be allowed to be made to external devices. In the case of the so-called "dubbing 10" provision, nine copies and one move process may be made to external devices.

In addition, 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 (accumulation) unit 110. However, if the broadcast receiving device 100 is configured to have a "temporary storage" mode that allows storage in the storage (accumulation) unit 110 only for a predetermined time or a predetermined time specified by control information included in the broadcast signal (for example, by the MH-Expire descriptor shown in FIG. 6D), the content can be temporarily stored in the storage (accumulation) unit 110 even if the copy control information included in the MPT indicates "copy prohibited". When the content for which the 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 control information indicating "copy prohibited".

The 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 and LAN communication unit 121, etc. The copy or move process to the aforementioned external device may be performed via the digital I/F unit 125 and LAN communication unit 121, etc. in FIG. 7A.

The process described above makes it possible to achieve appropriate content protection 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 is permitted only when the IP address of the external device that is the destination of the packet transmitted from the broadcast receiving device 100 is in the same subnetwork as the IP address of the broadcast receiving device 100, and may be prohibited when 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 "Copyable without limit and 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 "Copyable an unlimited number of times with encryption processing 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 possible if the IP address of the external device that is the destination of the packet sent from the broadcast receiving device 100 is in 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 output and audio output for viewing of the content stored in the storage (accumulation) unit 110 of the broadcast receiving device 100 are possible only when the IP address of the external device that is the destination of the transmission packet from the broadcast receiving device 100 is in the same subnetwork as the IP address of the broadcast receiving device 100, and are prohibited when 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 is 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, it may be configured to enable video output and audio output for viewing of the content stored in the storage (accumulation) unit 110 of the broadcast receiving device 100 to the external device 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 output and audio output for viewing are performed by encrypting the content.

According to the process described above, different processes are performed depending on whether the external device is in the same subnetwork as the IP address of the broadcast receiving device 100 or not, thereby achieving both user convenience and content protection.

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

First, when copy control information is included in the MPT, data included in the same package and the same event in the location information may be controlled according to the copy control information included in the TLV stream, even if the data was obtained via a different route (IPv4, IPv6, MPEG2-TS, URL, etc.) than the data obtained via the TLV stream of the broadcast route. As described above, the copy control state of the content specified by this copy control information can be specified as "unlimited copying" (which may be divided into two types: "unlimited copying and encryption processing required when storing and outputting" and "unlimited copying and no encryption processing required when storing and outputting"), "one generation only copying", "a specified number of copies" (for example, 9 copies + 1 move is the so-called "dubbing 10"), "no copying", etc.

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

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

In this operation, data acquired via a route other than the TLV stream can also be put into a copy state that is desired to be managed 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 storing in storage unit 110 or the like, recording on a removable recording medium, or outputting 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 in the broadcasting system that transmits the data.

In addition, if the comparison shows that the copy control status indicated by the copy control information included in the MPEG2-TS is the same as or more lenient than the copy control status indicated by the copy control information included in the TLV stream, copy control can be performed on the MPEG2-TS data included in the same package and the same event in the location information as content in the copy control status indicated by the copy control information included 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 in the broadcasting system that transmits 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. In addition to the MPT, the copy control information may be placed and transmitted in the MH-Service Description Table (MH-SDT) or MH-Event Information Table (MH-EIT) described in FIG. 6B, or in other tables, and the broadcast receiving device 100 may perform copyright protection processing according to 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 are omitted as much as possible to avoid duplication. In addition, 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 methods.

[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 decode processing unit 841, an MPEG2-TS decode 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 the same functions as 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 explanations are omitted.

The first tuner/demodulator 831 receives the broadcast waves of a broadcast service that employs MMT as a media transport method via an antenna (not shown), and tunes (selects) the channel of the service desired by the user based on the control of the main control unit 801. Furthermore, the first tuner/demodulator 831 demodulates the received broadcast signal to obtain an MMT data string, and outputs it to the MMT decode processor 841. The second tuner/demodulator 832 receives the broadcast waves of a broadcast service that employs MPEG2-TS as a media transport method via an antenna (not shown), and tunes (selects) the channel of the service desired by the user based on the control of the main control unit 801. Furthermore, the second tuner/demodulator 832 demodulates the received broadcast signal to obtain an MPEG2-TS data string, and outputs it to the MPEG2-TS decode processor 842.

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

The MPEG2-TS decode processing unit 842 inputs the MPEG2-TS data string output from the second tuner/demodulation unit 832, and performs processes such as separation and decoding of the real-time presentation elements such as the video data string, audio data string, superimposed text data string, and subtitle data string based on the control signal contained in the MPEG2-TS data string. The MPEG2-TS decode processing unit 842 has the same functions 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 will be omitted.

The video synthesis unit 861 inputs the video information, subtitle information, and application information output from the MMT decode processing unit 841 and the video information, subtitle information, and application information output from the MPEG2-TS decode processing unit 842, and performs appropriate selection and/or superimposition processing. The video synthesis unit 861 is equipped with a video RAM (not shown), and the monitor unit 862 and the like are driven based on the video information input to the video RAM. The video synthesis unit 861 also performs scaling processing, superimposition processing of EPG screen information, and the like 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 decode processing unit 841 and the audio information output from the MPEG2-TS decode processing unit 842, and performs appropriate selection and/or mixing processing.

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 part of it) and MPEG2-TS data sequence (or a part of it) of a program transmitted via a communication line, and outputs them to the MMT decoding processing unit 841 and the 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 the current time can be displayed on the EPG screen, various setting screens, etc. The information on the current date and the current time is transmitted by MH-TOT or the like in a broadcast service that adopts MMT as a media transport method, and is transmitted by TOT (Time Offset Table) or the like provided in SI (Service Information) defined in the MPEG-2 system in a broadcast service that adopts MPEG2-TS as a media transport method. The broadcast receiving device 800 can obtain the information on the current date and the current time by referring to the MH-TOT or the TOT.

In addition, generally, when the video synthesis unit 861 mainly selects the video information etc. output from the MMT decode processing unit 841, the information relating to the current date and current time obtained from the MH-TOT is superimposed on the video information etc., and when the video synthesis unit 861 mainly selects the video information etc. output from the MPEG2-TS decode processing unit 842, the information relating to the current date and current 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 when selecting a broadcast service that uses MPEG2-TS as the media transport method. For example, as shown in FIG. 25, when the screen display is switched 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, which may cause the user to feel a visual discomfort due to the inconsistency.

In the broadcast receiving device 800 of this embodiment, in order to prevent the user from feeling visually uncomfortable, even when the video synthesis unit 861 is primarily selecting video information, etc. output from the MMT decoding processing unit 841, the information relating to the current date and current time obtained from the TOT is controlled to be superimposed on the video information, etc. In other words, the current time information provided by a broadcast service that employs MPEG2-TS as a media transport method is controlled to be superimposed on the content of the broadcast service that employs MMT as a 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 visual discomfort due to inconsistencies in the display of the current time.

FIG. 26A shows an example of the selection control of the current time information reference source according to 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 a broadcast service that uses MPEG2-TS as the media transport method is available for reception, the device always refers to the TOT to acquire current time information, and only when a broadcast service that uses MPEG2-TS as the media transport method is unavailable for reception and a broadcast service that uses MMT as the media transport method is available for reception is the device controlled to refer to the MH-TOT to acquire current time information.

In addition, the same effect as described above can be obtained 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 manner to the above control.

As described above, in either case of controlling the content of a broadcast service that employs MMT as the media transport method to be superimposed with current time information provided by a broadcast service that employs MPEG2-TS as the media transport method, or controlling the content of a broadcast service that employs MPEG2-TS as the media transport method to be superimposed with current time information provided by a broadcast service that employs MMT as the media transport method, it is possible to correct the current time information by referring to the "delta" parameter of the time information in the TMCC extension information area, as explained in [Time management of the broadcast receiving device] in Example 1.

In addition, in both cases of 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 the MH-TOT or TOT transmitted by each broadcast service constituting the network may contain errors due to malfunctions in the transmitting system, transmission errors, etc. In the broadcast receiving device 800 of this embodiment, as a countermeasure against the errors in the MH-TOT or TOT, if it is determined that the MH-TOT or TOT acquired from the service being received contains an error, the device has a function to acquire the MH-TOT or TOT from another broadcast service on the same network or from an arbitrary broadcast service on another network and perform a process of updating the time information of the built-in clock by referring to the current time information.

Figure 26B shows an example of the process of updating current time information when a broadcast service that uses MPEG2-TS as the media transport method is being received in the broadcast receiving device 800 of this embodiment. Note that the same process as shown in the figure can be performed even when a broadcast service that uses MMT as the media transport method is being received.

When updating the time information of the built-in clock in the broadcast receiving device 800 of this embodiment, the receiving function execution unit 1102 first acquires the TOT from the MPEG2-TS data string of the currently being received broadcast service (broadcast service that employs MPEG2-TS as the media transport method) (S301), and then acquires the current time information by referencing the acquired TOT (S302). Next, the receiving function execution unit 1102 performs a process of comparing the current time information acquired in the process of S302 with the time information of the built-in clock.

If the result of the comparison process shows that the difference between the current time information acquired in the process of S302 and the time information of the built-in clock is within a predetermined value (for example, within 3 minutes) (S303: Yes), the reception function execution unit 1102 updates the time information of the built-in clock with the current time information acquired in the process of S302 (S306). On the other hand, if the result of the comparison process shows that the difference between the current time information acquired in the process of S302 and the time information of the built-in clock is not within a predetermined value (S303: No), or if the TOT acquired in S301 has a flag indicating that there is an error in the data, the reception function execution unit 1102 acquires a TOT from an MPEG2-TS data sequence of another broadcast service in the same network, or acquires an MH-TOT from an MMT data sequence of an arbitrary broadcast service (broadcast service that adopts MMT as a media transport method) of another network (S304), and further acquires current time information from the acquired TOT or MH-TOT (S305). The reception function execution unit 1102 can then perform the comparison process of S303 again using the current time information acquired in the process of S305.

By performing the above process, if the broadcast receiving device 800 of this embodiment determines that the MH-TOT or TOT acquired from the service being received contains an error, it is able to acquire the MH-TOT or TOT from another broadcast service on the same network, or from any broadcast service on another network, and refer to the current time information to update the time information of the built-in clock.

Note that if, during initial settings after shipping from the factory, repeating the processes of S304 to S305 fails to obtain current time information whose difference with the time information of the built-in clock falls within a specified range, the time information of the built-in clock can be set again using the current time information obtained in the process of S302. In this way, it is possible to deal with cases where there is an error in the time information of the built-in clock of the broadcast receiving device 800 of this embodiment.

[EPG display on broadcast receiving device]
Event schedule information of a broadcast service that adopts MMT as a media transport method is transmitted by MH-EIT, etc. On the other hand, event schedule information of a broadcast service that adopts MPEG2-TS as a media transport method is transmitted by EIT (Event Information Table) etc. provided in SI defined in the MPEG-2 system. Therefore, generally, when video information etc. provided by a broadcast service that adopts MMT as a media transport method is displayed, event schedule information (MH-EIT) of the broadcast service that adopts MMT can be acquired, and when video information etc. provided by a broadcast service that adopts MPEG2-TS as a media transport method is displayed, event schedule information (EIT) of the broadcast service that adopts 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 even when displaying video information provided by a broadcast service that employs MMT as the media transport method, or when displaying video information provided by a broadcast service that employs 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 employs MMT as the media transport method, and "M1 TV", "M2 Broadcast", "M3 Channel", "M4 TV", "TV M5", etc. are the broadcast station names of the broadcast service that employs MMT as the media transport method. Also, EPG screen 162j is an EPG screen created based on the EIT of a broadcast service that employs MPEG2-TS as the media transport method, and "T6 TV", "T7 Broadcast", "T8 Channel", "T9 TV", "TV TA", etc. are the broadcast station names of the broadcast service that employs MPEG2-TS as the media transport method.

For example, when a user is watching a broadcast program provided by a broadcast service that employs MMT as the media transport method and instructs the display of an EPG screen by operating a remote control (not shown), the initial screen of the EPG screen (not shown) is displayed. The initial screen of the EPG screen is an EPG screen created based on the MH-EIT of the broadcast service that employs MMT as the media transport method, and displays detailed information about the broadcast programs of each channel from 17:00 (nearby the current time) on October 7, 2014 (today). Next, if the user wishes to check detailed information about the broadcast programs of each channel from 20:00 on October 9, 2014, and instructs the update of the EPG screen by operating a remote control (not shown), EPG screen 162i is displayed.

Furthermore, if the user wishes to check detailed information on a broadcast program provided by a broadcast service that employs MPEG2-TS as the media transport method and instructs a network switch by operating a remote control (not shown), an EPG screen 162j is displayed. At this time, the broadcast receiving device 800 of this embodiment controls to display detailed information on the broadcast programs of each channel on the same day and in the same time slot (i.e., from 8:00 p.m. on October 9, 2014) as the EPG screen 162i that was displayed immediately before, rather than the initial screen of the EPG screen (i.e., detailed information on the broadcast programs of each channel from 5:00 p.m. on October 7, 2014) created based on the EIT of the broadcast service that employs MPEG2-TS as the media transport method.

The above-mentioned control enables the user to continuously check detailed information about broadcast programs on the same day and at the same time on multiple networks using different media transport methods with simple operations. In other words, the usability of the broadcast receiving device 800 is improved.

Figure 27B is a diagram showing an example of an EPG screen in the broadcast receiving device 800 of this embodiment that is different from the above. EPG screen 162k shows a state in which EPG screen 162i shown in Figure 27A is displayed and then scrolled in the channel direction (horizontal direction) by operating a remote control (not shown). That is, 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 employs MMT as the media transport method and channel information created based on the EIT of a broadcast service that employs MPEG2-TS as the media transport method are seamlessly displayed on the same time axis.

Therefore, even if the user desires to check channel information created based on the EIT of a broadcast service that adopts MPEG2-TS as a media transport method while checking channel information created based on the MH-EIT of a broadcast service that adopts MMT as a media transport method, it is possible to eliminate the need to instruct switching of networks by operating a remote control (not shown). Furthermore, the user can simultaneously check detailed information related to broadcast programs 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 and effects of this example are the same as those of Examples 1 and 2 unless otherwise specified. For this reason, the following mainly describes the differences between this example and Examples 1 and 2, and omits explanations of common points as much as possible to avoid duplication. In this example, the handling of presentation area information set by the layout setting table (LCT) shown in FIG. 18 will be described.

[Hardware configuration of broadcast receiving device]
The hardware configuration of the broadcast receiving device 100 is the same as that of the first embodiment, so a description thereof will be omitted.

[Program Data Structure]
FIG. 28 shows the structure of program data. The program data consists of information (asset 30003) to be presented to the broadcast receiving device 100, such as video, audio, and program linkage information, and control information. The program linkage information stores text information, graphic information, image information, or video information to be presented in accordance with the program video. FIG. 28 shows a PA message 30000 that describes the presentation method and acquisition destination information of the asset 30003, among the control information. The acquisition destination of the asset 30003 is described as MMT_general_location_info (FIG. 31) in the MP table (MPT) 30001 (FIG. 17) in the PA message 30000 (FIG. 30). In addition, a layout setting table (LCT) 30100 (FIG. 18) is arranged in the PA message 30000, and the layout of the area in which each asset 30003 should be presented is described. Examples of the layout of the presentation area are shown in FIG. 19A to FIG. 19D.

In the PA message 30000, a package list table (PLT) 30002 (Figure 32) is placed, and the acquisition destination of another PA message 30000 can be described by MMT_general_location_info (Figure 31) in the PLT. By specifying the acquisition destination of this PA message 30000, the PA message 30000 can be made into a hierarchical structure. The location types of the acquisition destination of the PA message 30000 and the asset 30003 are shown in Figure 33.

Normally, the hierarchical structure of the PA message 30000 is limited to two levels as shown in FIG. 28, but it is also possible to add more levels by placing a PLT 30002 in the second level PA message 30000.

Since assets are composed of Media Processing Units (MPUs), which are the processing units (Figure 29), the presentation area of the asset 30003 is specified by specifying the presentation area of the MPU in the MPU presentation area specification descriptor (Figure 34). The MPU presentation area specification descriptor is placed in the asset descriptor area of the MPT. Note that since a presentation area is specified for each MPU, a presentation method is also possible in which the presentation area of the same asset 30003 is changed during presentation. Note that in order to reduce the amount of data, a control method is also possible in which presentation areas are not specified for all MPUs belonging to the asset, but only the presentation area of the first MPU and the first MPU of the group of MPUs whose presentation area is to be changed.

[Example of asset presentation]
<Operation example 1>
The broadcast receiving device 100 acquires the presentation area information by reading the LCT 30100. FIG. 16 shows a flow in which the broadcast receiving device 100 acquires the control information of a program as an example of channel switching. The LCT 30100 is arranged in an MMTP packet and transmitted, similar to the MPT 30001. Since the MPT 30001 describes the designation information of the presentation area of the asset 30003, it is preferable that the LCT 30100 is acquired before the MPT 30001. As shown in FIG. 16, it is preferable that the LCT 30100 is acquired as a step between S209 and S210 and between S214 and S215. Even if the acquisition at the above timing is not possible, it is equally preferable if the LCT can be acquired before S216.

The LCT 30100 is placed in the PA message 30000, but the LCT 30100 relating to the asset 30003 corresponding to the second layer PA message is placed in the first layer PA message 30000 or the second layer PA message 30000. When presenting the asset 30003, the presentation area information of the LCT 30100 placed in the PA message 30000 to which the asset 30003 to be presented belongs is used preferentially. If the LCT 30100 is not placed in the PA message 30100 to which it belongs, the presentation area information of the LCT 30100 placed in the PA message 30100 at the higher layer is used.

By using the method of this operation example, if the same LCT 30100 is used for the entire program data in Figure 28, by placing a common LCT 30100 in the first layer PA message 30000, presentation area information can be obtained at an early stage, making it possible to present program data quickly.

<Operation example 2>
If the LCT 30100 is not included in the MMTP packet, the broadcast receiving device uses the presentation area information of the LCT 30100 acquired up to that point. In other words, the broadcast receiving device stores the presentation area information of the LCT 30100, and updates the stored presentation area information every time a new LCT 30100 is acquired.

However, immediately after an event occurs that invalidates the presentation area information used up until that point, such as when the power is turned on or the channel is changed, there is still no valid presentation area information, so even if the video and audio data of a program has been acquired, it may not be possible to present that data. Therefore, until valid presentation area information is acquired, presentation processing is performed assuming that the presentation area shown in FIG. 19A, for example, is set as temporary presentation area information. The setting in FIG. 19A is hereinafter referred to as the default setting. The presentation area shown in the default setting (FIG. 19A) is a full-screen display area set for a device with a device_id of 0, i.e., the main device, and 0 is assigned to layout_number, region_number, and layer_order.

Figure 35A shows a state in which only the main asset 30201 is presented using temporary presentation area information, while Figure 35B shows a state in which, after acquiring the LCT 30100, the sub-asset 30202 is also presented according to the program's original presentation area information. When temporary presentation area information is used, the presentation area designation of the main asset is ignored, and an area with layout_number 0 and region_number 0 is designated, and no other assets are presented. Note that here, a main asset refers to an asset for which region_number 0 is designated for the main device, or an asset transmitted by broadcast waves for which region_number 0 is designated, and a sub-asset refers to any other asset.

By setting temporary presentation area information in this way, it becomes possible to perform at least the presentation process of the main asset even before the information of LCT30100 is loaded.

<Operation example 3>
In the operation example 2, an example has been shown in which only the main asset is presented using default presentation area information until a new LCT30100 is obtained when changing channels, etc., but the LCT30100 used in the program that was being viewed up until that point may also be used. An asset (main asset) designated for an area with region_number 0 in the program after the channel change is presented in an area with region_number 0 in the presentation area information that was used up until that point, and other assets (sub-assets) are not displayed.

After obtaining the LCT30100 of the program after the channel change, all assets are presented using the presentation area information. If the LCT30100 used in the previously viewed program divides the display area as shown in FIG. 19B, the process of operation example 2 may be performed, and if the LCT30100 used in the previously viewed program performs an overlay display as shown in FIG. 19C, the process of operation example 3 may be performed. If the LCT30100 used in the previously viewed program has an area with region_number 1 or greater, a predetermined pattern or message may be displayed in the area.

By using the presentation area information of the program that was being viewed in this way, it becomes possible to perform at least the presentation process of the main asset even before the information of LCT30100 is loaded.

<Operation example 4>
Since there may be cases where the original channel is restored after the channel is changed, it is also possible to store the information of the LCT 30100 once read in association with the channel information, and use the stored presentation area information when the channel is restored. Note that if the latest LCT 30100 is stored for each of all channels that can be received by the broadcast receiving device 100, the convenience of controlling the presentation area when changing channels is improved.

Since the presentation area information may change even during a program, an expiration date is set in the LCT30100, and if the expiration date has passed when the channel is returned, the presentation area information is not used, and the default settings are used, or only the main asset is presented using the presentation area information of the program that was being viewed up until that point, as shown in operation example 2 or operation example 3. Alternatively, only the main asset may be presented using the expired presentation area information of that channel. Of course, once a new LCT30100 is obtained, the normal presentation method is restored. Note that the control may be performed by referencing the expiration date, but may also be performed by referencing the version instead of the expiration date information.

Figure 36A shows an example of setting an expiration date in an LCT 30100. It is set in the NTP long format in the LCT expiration date descriptor (ending_time). The descriptor is placed in the descriptor area of the LCT 30100 (Figure 18).

Alternatively, an expiration date can be set for each layout, as shown in the layout expiration date descriptor in Figure 36B.

Alternatively, an expiration date can be set for each area, as shown in Figure 36C as a presentation area expiration date descriptor.

You can set an expiration date for a single hierarchical level, or for multiple hierarchical levels. When setting an expiration date for multiple hierarchical levels, the earlier expiration date for each area is given priority.

This method allows you to effectively use presentation area information once it has been acquired, while taking into account its expiration date.

<Operation example 5>
In operation example 4, the presentation area information of a program is read once and stored, but it is also possible to prepare presentation area information (common presentation area information) to be used commonly by multiple programs on a channel for each channel, acquire the common presentation area information in advance in broadcast receiving device 100, and use the common presentation area information for each program.

The common presentation area information is acquired in advance by the broadcast receiving device 100 in the format of the LCT (Figure 18). To indicate that it is common presentation area information, the common presentation area descriptor shown in Figure 37 is used. This descriptor is placed in the descriptor area of the LCT (Figure 18), and the layout number of the common presentation area is listed together with the device number. The service_id represents the broadcast channel. Furthermore, the start time (beginning_time) and end time (ending_time) of the validity period of the common presentation area information are described in NTP long format. A full_set_flag is also described so that it can be confirmed that all information is present when updating information. The meaning of the full_set_flag is summarized in Figure 38.

This common presentation area information can be read periodically, such as once a day or once a week, for example, outside of broadcast hours. It can also be obtained from broadcast waves or via the Internet.

Note that in case the common presentation area information has not been loaded, the program data transmits the common presentation area information used in that program as LCT30100. At that time, the full_set_flag of the common presentation area descriptor indicates that this is only a portion of the common presentation area information.

By using this common presentation area information, asset 30003 can be presented quickly even immediately after the broadcast receiving device 100 is turned on or immediately after a program change, before LCT 30100 is obtained.

<Operation example 6>
Operation example 5 shows a method of utilizing common presentation area information, but even if the common presentation area information is transmitted via broadcast waves or the Internet on a channel, depending on the program, a presentation area with a layout that is not described in the common presentation area information may be used.

Specifically, layout information that is not described in the common presentation area information can be described in the LCT30100 of the program. In this case, the layout number of the common presentation area is described in the common presentation area descriptor (Figure 37), so the broadcast receiving device 100 determines whether the LCT30100 contains additional presentation area information that is not a common presentation area, and if so, uses that information. In this case, if the layout number and area number of the presentation area overlap with the common presentation area information, it is determined in advance which information is to be prioritized. In other words, depending on the broadcast system, the broadcast receiving device 100 may be configured to prioritize common presentation area information. Also, depending on the broadcast system, the broadcast receiving device 100 may be configured to prioritize program-specific presentation area information.

Furthermore, if a common presentation area descriptor (Figure 37) is not placed in LCT30100, all presentation area information described in LCT30100 is treated as being specified as not being common area information.

This program-specific additional presentation area information may be obtained from broadcast waves, but it may also be obtained via the Internet instead of from broadcast waves.

This method allows you to use common presentation area information while also using presentation area information optimized for each program.

<Operation example 7>
Asset 30003 is presented in one presentation area, but in cases where it is better to display it on as many terminals as possible, such as breaking news, it is better to present the same content on all terminals available at that time.

Specifically, in the overlap presentation area specification descriptor (Fig. 39), a layout_number is written that specifies the layout setting of the main device (a device with Device_id of 0) so that the same area setting is performed on other devices. This descriptor is placed in the descriptor area of the LCT30100 (Fig. 18).

Figure 40 shows an example in which the same screen is presented on a sub-device (mobile information terminal 700) in addition to a main device (broadcast receiving device 100).

In addition, in case the original program is returned to after the breaking news ends, the presentation area information used in the original program may be stored and used after the breaking news ends.

This method increases awareness of important and urgent information.

<Operation example 8>
The presentation area of each asset 30003 is specified by the MPU presentation area specification descriptor (FIG. 34) by specifying the layout_number (layout number) and region_number (region number). If there is no presentation area information corresponding to this layout number and region number, the asset 30003 cannot be presented, and is not presented. However, if the abnormal asset 30003 is presented in a partial area of the screen, it may not be immediately obvious that there is a display abnormality. Therefore, when an asset 30003 that cannot be presented occurs, an error message such as that shown in FIG. 41 is displayed.

This method allows the viewer to know that the display is not working properly.

<Operation example 9>
In the operation example 8, the operation when a presentation area without presentation area information is specified is described, but the operation when different assets 30003 specify the same presentation area is described below. In the case of an asset that displays some content, it cannot be displayed in the same presentation area, so the same presentation area must not be specified simultaneously by different assets 30003. If they are specified simultaneously, the asset transmitted by the broadcast wave is given priority. Alternatively, the presentation of the asset 30003 that first used the layout number and area number is continued, and the presentation of the asset 30003 specified later is prohibited. Alternatively, the presentation of all assets 30003 with overlapping area specifications is prohibited. If an asset 30003 that cannot be presented occurs, an error message as shown in FIG. 41 may be displayed.

However, it is possible that the same presentation area may be specified for different assets 30003, for example when adding additional asset information to a video asset to achieve higher gradation. In order to indicate that multiple assets are in a complementary relationship such that they constitute a single piece of content, dependency descriptor information is used. The data structure of the dependency descriptor is shown in Figure 42. When this dependency exists, presentation is permitted even when the same presentation area is specified.

To manage the presentation area designation of assets 30003, a management table showing which assets 30003 designate which presentation area may be used. An example of a management table is shown in Figure 43. Since assets 30003 with asset IDs 1 and 3, and asset IDs 2 and 4 are dependent on each other, display is permitted even if the same area is designated. On the other hand, asset 30003 with asset ID 7 is a video asset, and since there is no dependency and it designates the same area as asset ID 0, presentation is prohibited.

Asset 30003 with asset ID 1 is transmitted by broadcast waves, so this is given priority. As asset 30003 with asset ID 8 is likely to be audio that is paired with asset ID 7 because asset 30003 with the same acquisition source has been prohibited from presentation, it is also prohibited from presentation. As assets with asset IDs 2, 4, 6, and 8 are audio assets, and audio assets are not directly related to the presentation process in the monitor unit 162, they do not necessarily need to be managed in the management table. In other words, only video assets may be managed in the management table.

By controlling the presentation in this way, it is possible to prevent abnormal presentations from being made when there is an inconsistency in the control information.

<Operation example 10>
The dependency relationship of assets 30003 may be a parallel relationship in which content is not complete unless multiple dependent assets 30003 are available, or a subordinate relationship in which data for improving image quality is provided to a subjective asset 30003 by another asset 30003. The subjective asset 30003 can be presented alone, but the subordinate asset 30003 is likely to be presented abnormally if the subjective asset 30003 does not exist, so if the subordinate asset 30003 cannot be obtained, the subordinate asset 30003 is prohibited from being presented. Note that a multi-layer structure in which a subordinate asset 30003 is further subordinate to another asset 30003 may be adopted.

To specify a dependency relationship, it is necessary to determine in advance whether the asset 30003 described in the dependency descriptor (Fig. 42) indicates the asset 30003 that is dependent on the asset, or indicates the asset 30003 that is dependent on the asset. In the case of assets 30003 that are in a parallel relationship, the dependency descriptor (Fig. 42) is placed so that both depend on the other.

Another method for specifying a dependency relationship is to explicitly state the dependency relationship in the dependency descriptor (Figure 42). Figure 44 shows a dependency descriptor that explicitly states the dependency relationship. A parameter called dependency_type is specified, which indicates the type of dependency for the dependent asset. The meaning of dependency_type is shown in Figure 45. 0 means that one asset is dependent on the other, and 1 means that one asset is dependent on the other. In the case of a parallel relationship, each asset is specified as being dependent on the other asset.

An example of a presentation permission/prohibition management table is shown in Figure 46. Assets with IDs 3 and 4 are subordinate to assets with IDs 1 and 2, but presentation is permitted because assets with IDs 1 and 2 have been acquired. On the other hand, assets with IDs 9 and 10 are prohibited from presentation because the subordinate assets with IDs 7 and 8 have not been acquired.

Assets with IDs 11 and 12 are mutually dependent, but since both are available, presentation is permitted. On the other hand, assets with IDs 13 and 14 are also mutually dependent, but since asset with ID 14 has not been acquired, presentation of asset with ID 13 is prohibited. If an asset 30003 that cannot be presented occurs, an error message as shown in FIG. 41 may be displayed.

In this way, by controlling presentation while taking into account the dependency relationships, it is possible to prevent abnormal presentation when there is an inconsistency in the control information.

<Operation Example 11>
The broadcast receiving device 100 can present both the asset 30003 acquired from the broadcast wave and the asset 30003 acquired from the communication line (Internet), but depending on the state of the communication line, it may be impossible to acquire the asset 30003 via the communication line, or the broadcast receiving device 100 may not be connected to the communication line in the first place. Therefore, normally, only the broadcast video of the broadcast wave is displayed in full screen using the default setting (FIG. 19A), and when the asset 30003 via the communication line is acquired, the asset 30003 may be presented in a region specified according to the setting of the LCT 30100.

For example, the case will be described in which the area setting of the LCT 30100 is as shown in FIG. 19B, the broadcast video is set to be presented in area 0, and the asset 30003 via the communication line is set to be presented in area 1 and area 2. When only the broadcast wave video can be received, the broadcast video is displayed in full screen using the default setting (FIG. 19A), and when the asset 30003 via the communication line can be acquired, the area setting of the LCT 30100 is used, the broadcast video is presented in area 0 in FIG. 19B, and the asset 30003 via the communication line is presented in area 1 and area 2. In this case, the LCT 30100 may not be transmitted by the broadcast wave, but may be transmitted together with the asset 30003 via the communication line. By using the method of this operation example, it is possible to display according to the reception status of the actual program data. Note that, when only one of the assets 30003 via the communication line has been acquired and the other has not been acquired, the default setting (FIG. 19A) may be used. It is desirable to control so that the transition to the area setting in FIG. 19B occurs when assets 30003 via both communication lines are collected.
Example 4

The following describes Example 4 of the present invention. Note that the configuration and effects of this example are the same as those of Examples 1 to 3 unless otherwise specified. For this reason, the following mainly describes the differences between this example and Examples 1 to 3, and explanations of common points are omitted as much as possible to avoid duplication. In this example, an example of the operation of handling presentation area information set by the layout setting table (LCT) shown in FIG. 18 and handling of off-program content are described.

[Hardware configuration of broadcast receiving device]
The hardware configuration of the broadcast receiving device 100 is the same as that of the first embodiment, so a description thereof will be omitted.

[Example of asset presentation transformation]
<Operation example 1>
When changing channels using an electronic program guide (EPG), when a new program is selected on the EPG as shown in the dashed frame 30203 in Figure 47, if an LCT 30100 is obtained from the PA message 30000 of the new program while the EPG is displayed, then when the program is displayed, assets can be presented in accordance with the presentation area information specified by the program.

Alternatively, the presentation area information for each program can be incorporated into the EPG data (MH-EIT acquired from broadcast waves or a communication network, along with other necessary data stored in a storage unit such as a memory), and the presentation area information for the program to be newly changed can be read from the EPG data to acquire the presentation area information for that program more quickly. In this case, there is no need to use a separate tuner, and therefore fewer tuners are required.

Alternatively, presentation area information for each program can be distributed via the Internet, and a process for reading the presentation area information for each program can be performed in advance. In this case, there is also no need to use a separate tuner, so the number of tuners can be reduced.

When the EPG is displayed, a reduced version of the program video may be displayed on the child screen 30204. In this state, presenting sub-assets will be difficult to view, so the LCT setting for the program may be ignored and only the main asset may be presented on the entire child screen 30204. The LCT setting may be ignored in any situation where the display of sub-assets makes it difficult to view the main asset, not just in the child screen when the EPG is displayed.

<Operation example 2>
To accommodate viewing partway through a program, LCT30100 is repeatedly transmitted, but if LCT30100 is not transmitted for a certain period of time, including when broadcast reception is interrupted, the receiver determines that valid presentation area information is no longer available and sets the presentation area to the default setting (FIG. 19A). When reception is resumed and the presentation area setting has been changed, this can prevent abnormal presentation caused by the old presentation area setting remaining. The default setting is a setting that only presents the main asset, so there will be no abnormal presentation regardless of the program.

<Operation example 3>
If there is an inconsistency in the information of the LCT 30100 used in the program and there is no valid presentation area information, the default setting (Figure 19A) is used to ensure that only the main asset is displayed at a minimum.

<Operation example 4>
In the case where there are assets via the Internet in addition to broadcast waves, asset data via the Internet can be acquired, but if reception of broadcast waves is interrupted, the presentation area setting is maintained and the presentation of assets via the Internet continues for a certain period of time even if no LCT 30100 is acquired, or until a new presentation area setting is established. With this method, it is possible to continue presenting assets that can be presented even partially in an abnormal situation.

<Operation example 5>
In the case where there are assets via the Internet in addition to the broadcast waves, reception of the broadcast waves continues, but if it becomes impossible to obtain asset data via the Internet, the presentation area setting is changed to the default setting (FIG. 19A) and only the main asset is presented. For example, if the presentation area of the assets via the Internet is area 1 and area 2 in FIG. 19B and the presentation area of the broadcast screen is area 0, when the presentation of the assets via the Internet is no longer present, areas 1 and 2 will become the background color, which will be unsightly. In such a case, if the default setting (FIG. 19A) is used to display the broadcast screen (main asset) over the entire screen, it will not be unsightly and the screen can be used effectively.

When changing the presentation area settings to the default settings (Figure 19A) in the above process, an error message 30205 may be displayed to inform the user that data acquisition from the Internet is no longer possible (Figure 48).

[Handling of non-program content]
While watching a program, there may be cases where a user wishes to use content other than the program, such as content on the Internet or an application, etc. The process for such a case will be described below.

First, whether or not to permit the presentation of content outside the program while watching the program is set in the content control descriptor. The data structure of the content control descriptor is shown in Figure 49. This descriptor is placed in MPT30001 (Figures 17 and 28). In Figure 49, a parameter called contents_control_mode indicates whether or not the presentation of content outside the program is permitted.

Figure 50 shows the meaning of the content control modes. Mode 00 means that it is not permitted, and all other modes mean that it is permitted. There are three types of permission modes. Mode 01 allows presentation in a specified area. The area is specified using layout_number and region_number. Mode 10 allows the presentation of non-program content as long as the presentation of program content is not hidden. Mode 11 allows the presentation of non-program content, and the method of presentation is optional.

Figure 51 shows an example of mode 01. Program content is a main asset presented in area 30206 and a sub-asset presented in area 30207. Non-program content is displayed in area 30208. Here, presentation in a web browser 30209 is shown as an example. In the example of Figure 51, there is no overlap between the presentation area of the program content and the presentation area of the non-program content, but these areas may be overlapped and the non-program content may be presented on top of the program content.

Figure 52 shows an example of mode 10. Shown is the presentation of program content 30210 and non-program content 30209. The program content here is presented in a partial area of the broadcast receiver screen 162 as the full screen area specified by LCT 30100. That is, the top left position 30211 of the presentation area of program content 30210 corresponds to the position of left_top_pos_x = 0, left_top_pos_y = 0 in LCT 30100, and the bottom right position 30212 corresponds to the position of right_down_pos_x = 100, right_down_pos_y = 100 in LCT 30100. The position on the screen 162 of the broadcast receiver 100 at which the full screen area specified by the LCT is set is set in advance in the broadcast receiver 100 or by the viewer. Non-program content can be presented anywhere as long as it does not interfere with the presentation of program content. It should not overlap as an area, and if it does overlap, it should be presented behind the program content so as not to hide the presentation of the program content (Figure 53).

Figure 54 shows an example of mode 11. In this case, the relationship between the presentation of program content and non-program content is arbitrary. The presentation of non-program content may be performed so as to hide the presentation of program content.

As described above, being able to simultaneously view program content and non-program content provides greater convenience for viewers.
Example 5

The following describes Example 5 of the present invention. Note that the configuration and effects of this example are the same as those of Examples 1 to 4 unless otherwise specified. For this reason, the following mainly describes the differences between this example and Examples 1 to 4, and explanations of common points are omitted as much as possible to avoid duplication. In addition, 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 methods.

[Hardware configuration of broadcast receiving device]
The hardware configuration of the broadcast receiving device 800 is the same as that of the second embodiment, so a description thereof will be omitted.

[Asset type]
There are two media transport formats that correspond to assets: MMT and MPEG2-TS, which are distinguished by location_type in MMT_general_location_info (FIG. 31). The types of location types are shown in FIG.

[MPEG2-TS Packet Synchronization Control]
<Operation example 1>
Synchronization control of MMT packets is performed by a time stamp based on time information of the NTP (Network Time Protocol) shown in Fig. 3. As a hardware configuration, a clock inside the receiver synchronized with the NTP shown in Fig. 7C is used.

On the other hand, the MPEG2-TS format uses a time stamp based on time information called PCR (Program Clock Reference) to control synchronization. The protocol stack for the MPEG2-TS format is shown in Figure 55. This PCR-based time system consists of a 33-bit upper counter that operates at 90 kHz and a 9-bit lower counter that operates at 27 MHz. A count of 300 in the lower 9 bits corresponds to one count in the upper 90 kHz. This upper 33-bit counter completes one cycle in approximately 26.5 hours, and the counter returns to 0 (Figure 57). In contrast, a clock synchronized with the NTP consists of 32 upper bits (seconds) and 32 lower bits (decimal part). Therefore, a clock based on the NTP can express a period of approximately 136 years, and is a completely different system for expressing time from the PCR system (Figure 57).

Therefore, a receiver that processes MPEG2-TS packets must have an internal clock synchronized to the PCR in addition to a clock synchronized to the NTP, and must present assets according to that clock, or use the NTP clock based on the relationship between the PCR and NTP times to present assets. Also, when precise presentation synchronization is required between MMT assets and MPEG2-TS assets, it is desirable to know the relationship between the PCR and NTP times even when an internal clock synchronized to the PCR is present.

The relationship between PCR and NTP times can be obtained, for example, in the following way. First, on the transmitting side, one method of providing the correspondence between PCR and NTP times is to describe that relationship for each MMT package table. That is, this is described as an MPT_descriptor in the MPT in FIG. 17. An example of a descriptor is shown in FIG. 56. Here, the timestamp_offset parameter gives the difference between the timestamp based on the PCR and the timestamp based on the NTP (timestamp offset). Here, the time based on the NTP corresponding to the time when the counter of the PCR timestamp used in the asset group indicated by the MPT was reset to 0 is shown in 64-bit NTP timestamp format.

To explain using Figure 57, if A in the figure is the PCR timestamp, B in the figure is the timestamp offset. If this timestamp offset value is used, the value of the NTP-based timestamp can be obtained by adding the value of the PCR timestamp offset to the timestamp offset. If the value of the NTP-based timestamp can be obtained, even for MPEG2-TS type assets, the presentation process can be performed using an NTP-based clock, enabling precise presentation synchronization with MMT type assets.

It is also possible to describe the timestamp offset for each asset that corresponds to the MPEG2-TS format. In this case, it is described as asset_descriptor in the MPT in Figure 17.

Note that if the PCR timestamps used in an asset include ones that exceed 0, there may be multiple times when the counter value of the PCR timestamp corresponds to 0. In that case, the timestamp offset can be written with the earliest time. Explained with reference to FIG. 57, this is the case when the PCR timestamps used in an asset are A' in addition to A. In this case, the value of B is used as the timestamp offset written in the descriptor. In the presentation process of an MPEG2-TS asset, the value of the timestamp offset written in the descriptor is used at first, and if the value of the PCR timestamp decreases when viewed in chronological order of the packets as the presentation process proceeds, it is determined that the counter has completed one cycle, and the time offset value used in the process is added with the time of one cycle of the PCR counter, i.e., the value obtained by dividing 2 to the power of 33 by 90 kHz (approximately 26.5 hours), and the process continues as the new time offset value. If the value of the PCR time offset decreases during processing thereafter, the value of the timestamp offset can be updated in the same way.

<Operation example 2>
Next, a process when the sending side does not describe the timestamp offset will be described. If the sending data does not describe the timestamp offset, when the PCR timestamp is received, the value of the NTP clock in the receiving device at the time of reception is read, and the time of the NTP clock corresponding to the time when the PCR timestamp counter was reset to 0, as described above, is set as the value of the timestamp offset. After the timestamp offset value is set, the presentation process of the MPEG2-TS format asset can be performed in the same manner as when the timestamp offset value is described in the above-mentioned descriptor.

When watching a program as it is being broadcast, even if the timestamp offset value is not described in the descriptor in the transmission data, it is possible for the receiving device to obtain it, for example, as described above. However, when recording a program and playing it back, it is difficult to obtain the relationship between the NTP timestamp and PCR timestamp values. Therefore, when recording a program that contains a mixture of MMT and MPEG2-TS assets, it is desirable to simultaneously record the timestamp offset descriptor. If the transmission side does not describe the timestamp offset in the transmission data, it is desirable to obtain the timestamp offset value at the receiving device and add it to the received data before recording and recording. These recorded and recorded data may be recorded, for example, in the storage unit 810 in FIG. 24. When watching, the recorded data may be played back from the storage unit 810 and used.

As described above, by using a timestamp offset that gives the relationship between the NTP timestamp and the PCR timestamp to process assets for presentation, more precise presentation synchronization processing becomes possible in programs that contain a mixture of MMT and MPEG2-TS assets.

<Operation example 3>
The presentation area of an asset transmitted by the MMT media transport method is specified by the MPU presentation area designation descriptor (FIG. 34), but the presentation area of an asset transmitted by other media transport methods such as the MPEG2-TS method may also be specified by the MPU presentation area designation descriptor (FIG. 34). In this case, designations that are meaningless depending on the type of asset, such as mpu_sequence_number, are ignored. This makes it possible to present assets without using a special designation method, improving convenience.

Note that if the mpu_sequence_number specification is ignored, the presentation area of the entire asset specified in the MP table (MPT) 30001 (Figures 17 and 28) shall follow the area specification in the MPU presentation area specification descriptor (Figure 34).

<Operation example 4>
The presentation time of an asset transmitted by the MMT media transport method is specified by the MPU timestamp descriptor (FIG. 58), but the presentation time of an asset transmitted by other media transport methods such as the MPEG2-TS method may also be specified by the MPU timestamp descriptor (FIG. 58). In this case, the receiver ignores designations that are meaningless depending on the type of asset, such as mpu_sequence_number. In this case, the time to be specified is the presentation time of the head of the asset, and by using this time information, the difference between the NTP timestamp and the PCR timestamp can be obtained, and the presentation of the asset transmitted by the MMT method and the asset transmitted by the MPEG2-TS method can be synchronized. This makes it possible to present an asset without using a special designation method, improving convenience.

<Operation example 5>
In the operation examples 3 and 4, the method of using the MPU presentation area designation descriptor (FIG. 34) and the MPU time stamp descriptor (FIG. 58) for the presentation of assets transmitted by a method other than the MMT method has been shown, but a dedicated descriptor may be used. As an example of a dedicated descriptor, the asset presentation area designation descriptor (FIG. 59) and the asset time stamp descriptor (FIG. 60) may be used. In these descriptors, information that is meaningless in a method other than the MMT method, such as mpu_sequence_number, is not described. This improves reliability without causing confusion in the process.

The descriptor that transmits the timestamp offset or the descriptor that transmits the presentation time of an asset other than the MMT media transport method described above in the operation examples 1, 3, 4, and 5 is transmitted as a descriptor in the MMT package table. In this case, it is transmitted as data that is received by the tuner/demodulator 831 in FIG. 24 and decoded by the MMT decoding processing unit 841.

However, as a variation of this operation example, the data may be received by the tuner/demodulation unit 832 and transmitted as data that is decoded by the MPEG2-TS decoding processing unit 842.

As described above in the fifth embodiment, the synchronized asset video transmitted in the MMT format and the asset video transmitted in the MPEG2-TS format can be generated and output as a composite video by the video synthesis unit 861 in FIG. 24 so as to be presented in one of the areas into which the screen is divided based on the LCT described in the first to fourth embodiments.

Although examples of the embodiment of the present invention have been described above using Examples 1 to 5, the configurations for realizing 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, and it is also possible to add the configuration of another example to the configuration of one example. All of these fall within the scope of the present invention. Furthermore, the numerical values and messages that appear in the text and figures are merely examples, and the effect of the present invention will not be impaired even if different ones are used.

The functions of the present invention described above may be realized in part or in whole by hardware, for example by designing them as integrated circuits. They may also be realized by 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 in combination.

The software that controls the broadcast receiving device 100 may be stored in the ROM 103 and/or storage (accumulation) unit 110 of the broadcast receiving device 100 beforehand at the time of product shipment. It may also be acquired via the LAN communication unit 121 from another application server 500 on the Internet 200 after product shipment. In addition, the software stored in a memory card, optical disk, etc. may be acquired via the expansion interface unit 124, etc.

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...Broadcast receiving device, 100a...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...Digital interface unit, 131, 831, 832...Tuner/demodulation unit, 132...Separation unit, 141...Video decoder, 142...Video color gamut conversion unit, 143...Audio decoder, 144...Text 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, 156...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, 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, 400...service provider server, 500...other application servers, 600...mobile telephone communication server, 600b...base station, 700...mobile information terminal.

Claims (1)

A content protection processing method in a broadcast receiving device of a transmission system in which date and time information including a current date and time, control information related to a broadcast program, and broadcast program content are transmitted from a broadcast station, and the date and time information, the control information related to the broadcast program, and the broadcast program content are received by the broadcast receiving device, the method comprising:
a receiving step of receiving the date and time information, the control information related to the broadcast program, and the broadcast program content;
a recording reservation step of reserving a recording of the broadcast program by using the date and time information and an EIT in which information related to an event is described among the control information received in the receiving step;
a storage step of storing the broadcast program content received in the receiving step, using copy control information of the control information received in the receiving step, for the broadcast program reserved for recording in the recording reservation step;
an output step of outputting the broadcast program content stored in the storage step to an external device in a copy-protected state;
Equipped with
The current date and time included in the date and time information represents Japan Standard Time,
With regard to the broadcast program content stored in the storing step, when the broadcast program content received in the receiving step is a content that can be copied without restriction in the transmission system and is transmitted with protection by encryption specified, the broadcast program content is stored in an encrypted state so that it can be played back only by the broadcast receiving device,
The storage of the broadcast program content in the storage step can be performed in a storage unit at the output destination of the IP interface provided in the broadcast receiving device via an IP interface of the broadcast receiving device, and the storage of the broadcast program content in the storage unit in the storage step in an encrypted state so that it can be played back only by the broadcast receiving device, and the output of the broadcast program content to an external device in a copy-protected state in the output step can be performed via an IP interface configured with the same hardware compatible with Ethernet.
Content protection processing method.

Images