JP7204615B2 - CONTENT TRANSMISSION DEVICE, TRANSMISSION METHOD - Google Patents

Description

The embodiments relate to a content transmission device and a transmission method.

A receiver for BS digital broadcasting, 110-degree CS digital broadcasting, and terrestrial digital broadcasting (hereinafter referred to as the preceding three waves) can transmit received broadcast content to a home IP (Internet Protocol) network. Such content transmission is performed by the receiver serving as a content server (hereinafter referred to as a server) based on DLNA (registered trademark) (Digital Living Network Alliance), and the transmitted content is sent to the server by the home IP network. received by a DLNA-based content client (hereafter referred to as client) interconnected with the In transmitting content, it is necessary to apply a content protection technology that is defined as appropriate by each broadcasting standard. DTCP (Digital Transmission Content Protection), for example, is defined as a corresponding content protection technology.

In December 2018, a new 4K/8K satellite broadcast was launched in addition to the three preceding waves. The receiver of the new 4K8K satellite broadcast can also transmit the received new 4K8K satellite broadcast content to the home IP network on the premise that the content protection technology is applied, like the receivers of the preceding three waves. DTCP2 (Digital Transmission Content Protection Two) is defined as an appropriate content protection technology.
A new 4K8K satellite broadcast receiver may be a receiver capable of receiving the preceding three waves (hereinafter referred to as a shared receiver). In this case, the shared receiver can serve as a server and transmit the content of the new 4K8K satellite broadcast and the content of the preceding three waves to surrounding clients over the home IP network.

By the way, the new 4K8K satellite broadcast content and the content of the preceding three waves use different character encoding methods. The former is UTF-8 and the latter is an 8 unit code.

ARIB TR-B14 Version 6.5 "Operational Regulations for Terrestrial Digital Television Broadcasting" (Volume 4) ARIB TR-B15 Version 7.1 "BS/Broadband CS Digital Broadcasting Operation Regulations" (Volume 1) ARIB STD-B21 Version 5.10 "Digital broadcasting receiver standard" ARIB TR-B39 Version 1.7 "Advanced Broadband Satellite Digital Broadcasting Operational Regulations" (Volume 1) ARIB STD-B60 Version 1.12 "Advanced Broadband Satellite Digital Broadcast Receiver Standard" ARIB STD-B62 Version 1.9 "Multimedia Coding Method for Digital Broadcasting (Second Generation)" (Volume 1) ARIB STD-B63 Version 1.7 "Advanced Broadband Satellite Digital Broadcast Receiver Standard"

However, the related applicable standards and operational regulations do not specify the fields to be placed in the content data to indicate the character encoding method used in the content, and the client receiving the content can There is no way to know the character encoding used in the transmitted content. Therefore, there is a possibility that the client may perform incorrect processing on the character data included in the content, causing malfunctions such as displaying a character string different from the intended one (hereinafter collectively referred to as garbled characters). In particular, if the server has a recording function or a content editing function, the character encoding method is converted when content is recorded on a recording medium, or multiple pieces of content with different character encoding methods are combined into one. It is also assumed that the contents will be reconstructed as one content, and there is a high possibility that the characters will be garbled when the client receives such content.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a content transmission device and a transmission method that make it possible to use character data in content without garbled characters.

A content transmission device according to one embodiment includes encoded content data input/output means, analysis means, and transmission means, and the encoded content data input/output means is configured to transmit content including at least character data transmitted by a broadcast signal. First encoded content data obtained by encoding data and first content accompanying information attached to the first encoded content data are input, and second encoded content data obtained by encoding the content data and second encoded content data are inputted. second content-accompanied information accompanying the encoded content data is output, and the analysis means analyzes the second content-accompanying information and extracts information on the character encoding method used in the second encoded content data. , and the transmitting means includes the extracted character encoding method in a DTCP2 standard CMI (Content Management Information) packet and transmits it to the outside together with the second encoded content data.

1 is a block diagram illustrating an example of a functional configuration of a server according to an embodiment; FIG. FIG. 2 is a block diagram illustrating an example of a functional configuration of a client according to the embodiment; 3 is a flowchart illustrating an example of a processing operation of a server according to the first embodiment; FIG. FIG. 4 is a flow chart showing an example of a client processing operation according to the first embodiment. FIG. 5A is a flowchart showing an example of processing operations of a server according to the second embodiment; FIG. 5B is a flowchart showing an example of the processing operation of the server according to the second embodiment; FIG. 6 is a diagram showing an example of parameters transmitted by the server in the second embodiment. FIG. 7A is a flowchart showing an example of processing operations of a client according to the second embodiment; FIG. 7B is a flowchart showing an example of processing operations of a client according to the second embodiment; FIG. 8 is a flowchart illustrating an example of a processing operation of a server according to the third embodiment; FIG. 9 is a diagram showing an example of the configuration of the SIT transmitted by the server in the third embodiment. FIG. 10 is a flow chart showing an example of the processing operation of the client according to the third embodiment. FIG. 11 is a flowchart illustrating an example of processing operations of a server according to the fourth embodiment; 12A is a diagram showing an example of protection management information transmitted by a server in the fourth embodiment; FIG. 12B is a diagram showing an example of a field of protection management information transmitted by the server in the fourth embodiment; FIG. FIG. 12C is a diagram showing an example of a descriptor written in a field of protection management information transmitted by a server in the fourth embodiment; FIG. 13 is a flow chart showing an example of a client processing operation according to the fourth embodiment.

Embodiments will be described below with reference to the drawings.

1 is a block diagram illustrating an example of a functional configuration of a server according to an embodiment; FIG.

The server 10 is a shared receiver that can receive both the content data transmitted by the new 4K8K satellite broadcasting and the content data transmitted by the preceding three waves, receives and processes the broadcast signal, decodes and reproduces it, and obtains it. The content data obtained can be displayed and output as video, audio, text, and the like. The server 10 is, for example, a television receiver capable of viewing the new 4K8K satellite broadcast and the preceding three waves. Generally, the character encoding method for character content transmitted by broadcast signals is uniquely determined according to the type of broadcast signal. Therefore, the server 10 can perform decoding and reproduction corresponding to the character encoding system required for receiving the broadcast signal as a shared receiver, but the server 10 can decode and reproduce the character encoding system other than the character encoding system required for receiving the broadcast signal. An encoding method and a decoding reproduction method may be provided. Further, the server 10 can store content data or content data before decoding/playback (hereinafter referred to as encoded content data when particularly distinguished) in the storage unit 13 as digital data. In addition, the server 10 can output content data to an external device (client) using a network conforming to DLNA (registered trademark) or the like.

The broadcast signal receiving unit 11 receives a broadcast signal via an antenna (not shown), acquires encoded content data, and outputs it as content data that can be output as video, audio, and text. In addition, the broadcast signal receiving unit 11 can output interim data acquired until the content data is obtained from the received broadcast signal of the new 4K/8K satellite broadcast and the broadcast signals of the preceding three waves. Intermediate data includes MMT/TLV streams and control information generated by the MPEG Media Transport method (hereinafter referred to as MMT method) used in the new 4K8K satellite broadcasting, and MPEG-2 Transport Stream method used in the preceding three wave broadcasts. (hereinafter referred to as the TS system), transmission control information, program-related information, and the like. Also, the broadcast signal receiving unit 11 can appropriately convert the acquired content data and encoded content data, and output them to the storage unit 13 or the like together with related control information, transmission control information, program-related information, and the like. . Normally, the broadcast type and the character encoding method for the character data transmitted by the broadcast match. As a result, in the data stored in the storage unit 13, there are cases where the broadcast type and the character encoding method for the character data do not always match. In addition, in the data stored in the storage unit 13, a plurality of encoded content data with different character encoding methods are combined so that the encoded content data including a plurality of character data encoded with different character encoding methods can be encoded. Content data may exist.

The display output unit 12 is, for example, a monitor or a speaker capable of outputting content data output from the broadcast signal receiving unit 11 and the storage unit 13 as video, audio, and characters that can be used by the user.

The storage unit 13 is a storage device capable of storing data output by the broadcast signal receiving unit 11, and is, for example, a hard disk. In addition, the storage unit 13 can output saved data. Further, the storage unit 13 may have a function of editing a program stored (recorded). In this case, for example, the 4K8K program and the programs of the preceding three waves can be cut and pasted or combined into one content. Encoded content data combined with encoded content data transmitted by 4K8K satellite broadcasting can be stored. In this case, as for the encoding method of the combined encoded content data, the encoded content data portion of the new 4K8K satellite broadcast encoded by the MMT method may be re-encoded to the MPEG2 TS method and the whole may be set to the MPEG2 TS method. Alternatively, the encoded contents data portion of the preceding three waves encoded by the MPEG2 TS system may be re-encoded by the MMT system and the whole may be made by the MMT system. Alternatively, both the encoded content data part of the new 4K8K satellite broadcast and the encoded content data part of the preceding three waves are converted into an encoding system neither MPEG2 TS system nor MMT system, and the combined encoded content data may be used as the encoding method. Note that the function of editing the saved (recorded) program may be provided as a function within the server 10 instead of the storage unit 13 .

The analysis unit 14 analyzes the control information output by the broadcast signal reception unit 11, the content data stored in the storage unit 13, or the accompanying information attached to the encoded content data. Content management information such as the character encoding method of encoded character data (hereinafter referred to as encoded character data) is extracted.

The accompanying information generation unit 15 converts the content management information extracted by the analysis unit 14 into a format that can be transmitted to the client.

The character data conversion unit 16 converts the character encoding method of the encoded character data output from the broadcast signal receiving unit 11 and the storage unit 13 (or output via the analysis unit 14), and converts the converted character data ( hereinafter referred to as conversion-encoded character data) is output.

The control unit 17 controls each function within the server 10 . For example, the character data conversion unit 16 is designated whether or not to execute encoding conversion of encoded character data, or a conversion method in the case of execution. In FIG. 1, data may also be exchanged with functional blocks that are not particularly connected to the control unit 17 .

The content stream generation unit 18 generates a content stream from data such as encoded content data including conversion-encoded character data output by the character data conversion unit 16 and control information including content management information generated by the accompanying information generation unit 15. Generate.

The content protection unit 19 implements content protection such as encryption on the content stream generated by the content stream generation unit 18 . Techniques used for content protection are, for example, techniques conforming to standards such as DTCP (Digital Transmission Content Protection) and DTCP2 (Digital Transmission Content Protection Two). Whether the content protection function of the content protection unit 19 is enabled or disabled is determined based on content protection instruction information (specifically, digital copy control descriptor, content usage control descriptor, etc.) included in the broadcast signal.

The transmission/reception unit 110 transmits the content-protected content stream output by the content protection unit 19 (hereinafter referred to as a protected content stream) to the client 20 as a content stream signal using a predetermined communication method. The transmission/reception unit 110 in this embodiment employs a communication method based on IP communication conforming to DLNA (registered trademark) (hereinafter, particularly referred to as server/client communication when distinguished from reception of broadcast signals). Although wireless communication is used as a communication medium for server/client communication, there is no particular limitation, and a wired communication medium may also be used. The server 10 can also output a content stream without content protection, which is output by the content stream generation unit 18 without going through the content protection unit 19, as a content stream signal. Whether or not to protect the content stream is selected by the control unit 17 based on, for example, control information received by the broadcast signal receiving unit 11 (specifically, digital copy control descriptor, content usage control descriptor, etc.).

FIG. 2 is a block diagram illustrating an example of a functional configuration of a client according to the embodiment;

The client 20 receives the content stream signal transmitted by the server 10, processes it, and displays and outputs video, audio, character data, and the like. The client 20 is, for example, a television receiver, a tablet, a smart phone, or the like that is different from the server 10 . Also, the client 20 does not necessarily have to be a receiver of the new 4K8K satellite broadcast or the preceding three waves. Also, the client 20 may be capable of processing both the character encoding method used in the new 4K8K satellite broadcasting and the character encoding method used in the preceding three waves, or may be capable of processing only one of them. may

The transmitting/receiving unit 21 is an interface capable of communicating with the transmitting/receiving unit 110 of the server 10, receives a content stream signal transmitted from the server 10 by a predetermined communication method, processes it, and outputs a content stream. In this embodiment, a communication method based on IP communication conforming to DLNA (registered trademark) is provided for the transmission/reception unit 110 .

The control unit 22 controls each function within the client 20 . In FIG. 2, data may also be exchanged with functional blocks that are not particularly connected to the control unit 22 .

The content stream processing unit 23 performs content protection release processing, demultiplexing (separation processing), decoding playback, etc., on the content stream output by the transmitting/receiving unit 21 as necessary, extracts content data, and outputs the content data for display. Content data is output to the unit 24 . The display output unit 24 displays and outputs the content data as video, audio, and characters.

The analysis unit 25 extracts the content management information from the signal received by the transmission/reception unit 21 and outputs it to the control unit 22 or the transmission/reception unit 21 or the content stream processing unit 23 .

(First embodiment)
In this embodiment, the server 10 selects the character encoding method of the character data sent by the server 10 according to the character encoding method that can be processed by the client 20, and converts the character data. For example, if the client 20 can process the character data of the new 4K8K satellite broadcast, the server 10 uses UTF-8 as the character encoding method. An octet code is used as the encoding method. An operation example of the system according to this embodiment will be described below.

FIG. 3 is a flow chart showing an example of the processing operation of the server according to the first embodiment.
The server 10 establishes a communication path with the client 20 in server/client communication (step S31). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 . The control unit 17 obtains from the client 20 information on the character encoding system that can be processed by the client 20 when this communication path is established. Alternatively, instead of obtaining the information from the client 20, if the user knows in advance the character encoding method that can be processed by the client 20, for example, the server 10 transmits the information to the client 20 from a remote controller (not shown). A character encoding method for character data may be set.

When the control unit 17 detects a content data transmission request to the client 20 , the control unit 17 inputs the encoded content data from the broadcast signal receiving unit 11 and the storage unit 13 to the analysis unit 14 . The analysis unit 14 analyzes the content accompanying information accompanying the encoded content data (YES in step S32, step S33). The content-associated information includes information related to content such as program information and a data processing method. , the extracted information about the character encoding system is input to the control unit 17 . The control unit 17 receives the information on the character encoding method (hereinafter referred to as the first character encoding method) extracted by the analysis unit 14 and the character encoding method available to the client 20 obtained in step S31 (hereinafter referred to as the first character encoding method). 2 character encoding). As a result of the comparison, if the two match, the control unit 17 transmits encoded content data including encoded character data according to the first character encoding method from the broadcast signal receiving unit 11 and the storage unit 13 to the content stream generating unit 18. (YES in step S34). On the other hand, if the two do not match (NO in step S34), the control unit 17 inputs the encoded content data from the broadcast signal receiving unit 11 and the storage unit 13 to the character data converting unit 16. FIG. The character data conversion unit 16 decodes and reproduces the encoded character data of the encoded content data using the first character encoding method, and again encodes and outputs the encoded character data using the second character encoding method (step S35). For example, this corresponds to the case where the client 20 can only support the character encoding method of the preceding three waves and cannot support the character encoding method of the character content by the new 4K8K satellite broadcast received by the server 10 .

In this embodiment, the case where the character encoding method (second character encoding method) that can be processed by the client 20 is valid in the server 10 is shown. If it is invalid, the display output unit 13 of the server 10 can notify the user of an alarm.

The content stream generation unit 18 generates a content stream including the input encoded content data and data such as control information (step S36). The content stream may be, for example, a transport stream conforming to the MPEG2 system, an MMT/TLV stream conforming to the MMT/TLV system, or the like.

It is confirmed whether content protection is necessary or not (step S37). Specifically, for example, when server/client communication is established in step S31, the server 10 and the client 20 determine whether content protection is necessary or not. When content protection is required, the content protection unit 19 performs content protection processing on the content stream output from the content stream generation unit 18 by encrypting it by a predetermined method, adding necessary data, or the like, thereby generating protected content. The stream is output to the transmission/reception unit 110 (YES in step S37, step S38). In step S37, if content protection is not required, the content stream generated by the content stream generation unit 18 is output to the transmission/reception unit 110 (NO in step S37).

Transmitter/receiver 110 outputs the input content stream or protected content stream to the outside as a content stream signal by a predetermined communication method (step S39). For example, the transmitting/receiving unit 110 outputs DLNA (registered trademark) compliant IP communication data as a Wi-Fi (registered trademark) compliant wireless signal. When there are no more content transmission requests, the process ends (NO in step S32).

FIG. 4 is a flowchart showing an example of processing operations of a client according to the embodiment;
The client 20 establishes a communication path with the server 10 in server/client communication (step S41). Upon receiving the content stream signal, the transmission/reception unit 21 performs necessary processing such as demodulation, and outputs the content stream or protected content stream (YES in step S42). The output content stream is input to the content stream processing unit 23 and processed by the content stream processing unit 23 to obtain content data (step S43). Also, the content stream processing unit 23 performs content protection release processing on the protected content stream, and acquires content data from the obtained content stream. The acquired content data is output to the display output unit 24 and displayed as video, audio, and character data (step S44). The client 20 ends the process when it stops receiving the content stream signal (NO in step S42).

Thus, in this embodiment, the server 10 analyzes the encoded content data to be sent to the client 20, and if the character encoding method used is not valid for the client 20, the server 10 By converting the encoded content data into an effective character encoding method and transmitting the encoded content data, the client 20 can use the content data without causing garbled characters in the character content.

Also, when the receiver for the new 4K8K satellite broadcasting and the first three waves is a server (DMS in DLNA (registered trademark)) equipped with a content transmission function, it transmits to the client (DMR/DMP in DLNA (registered trademark)) The content to be displayed can be both a program of the new 4K8K satellite broadcast and a program of the preceding three waves. . In such a case, when the client 20 receives character data in an invalid character encoding method, garbled characters occur. Further, the character encoding method is not limited to UTF-8 and 8-bit code, and the same problem occurs even in the case of other character encoding methods. According to this embodiment, the server 10 converts the character data into a valid character encoding method for the client 20, so that the client 20 can use the content data without garbled character content.

Also, whether the server 10 is a receiver compatible with the new 4K8K satellite broadcasting and whether it is a receiver compatible with the preceding three waves is determined whether the server 10 can process UTF-8 and whether it can process 8 unit codes. For example, even if the server 10 is a receiver that supports only the preceding three waves, if it can process a plurality of character encoding methods, the server 10 will not cause garbled characters according to the present embodiment. It becomes possible to provide the client 20 with content data that does not exist.

(Second embodiment)
In this embodiment, an example is shown in which the server 10 transmits to the client 20 information on the character encoding method applied to the character data together with the content data.

The method according to the present embodiment is a method of putting character encoding information into a DLNA (registered trademark) media format profile (hereinafter simply referred to as profile). Two examples of operation will be described according to the method of a "content transmission request" that serves as a trigger for the server 10 to transmit content, and the processing method when the information on the character encoding method in the media format profile of the client 20 is confirmed.
First, using FIGS. 5A and 7A, the user executes a "content transmission request" to the server 10 by operating the remote control, and the client 20 confirms the information on the character encoding method in the media format profile, A case of returning (ACK transmission) to the server 10 information indicating whether or not the checked character encoding method is compatible will be described.
Second, using FIGS. 5B and 7B, the client 20 executes a “content transmission request” to the server 10, and after confirming the information on the character encoding method in the media format profile, the client 20 receives the confirmation result. A case where no reply (ACK transmission) is made to the server 10 is shown.
An operation example of the first system will be described below.

FIG. 5A is a flow chart showing an example of the processing operation of the server according to this embodiment.

The server 10 establishes a communication path with the client 20 in server/client communication (step S50). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 . When the user executes a "content transmission request" to the server 10 by operating the remote controller or the like, and a request to transmit content data is generated in the server 10, the analysis unit 14 analyzes the encoded content data (YES in step S51). , step S52). Specifically, in step S52, the analysis unit 14 extracts the character encoding method of the encoded character data input from the broadcast signal receiving unit 11 or the storage unit 13 from the content accompanying information. The character encoding method of the encoded character data extracted by the analysis unit 14 is input to the accompanying information generation unit 15 . The accompanying information generation unit 15 generates content management information according to the character encoding method of the input encoded character data. For example, this content management information is ARIB. OR. The parameter indicated by JP_PN (hereinafter referred to as ARIB.OR.JP_PN parameter), but is not limited to this. protocolInfo is a property described in a DIDL-Lite document, which is an XML document that is exchanged over a DLNA (registered trademark)-compliant network. may be placed.

FIG. 6 is a diagram showing an example of parameters transmitted by the server in the same embodiment.

This parameter indicates the profile of the content data transmitted by the server 10, and is particularly referred to as Profile ID. The meaning of each Profile ID is explained below.

No1: TS_JP_UTF8
It contains character data encoded in UTF-8 and is transmitted as a content stream conforming to the TS system.

No2: TS_JP_8UNIT
It contains character data encoded with an 8-bit code, and is transmitted as a content stream conforming to the TS system.

No.3: MMT_JP_UTF8
It contains character data encoded in UTF-8, and is transmitted as a content stream conforming to the MMT method.

No.4: TS_JP_8UNIT
It contains character data encoded with an 8-bit code, and is transmitted as a content stream conforming to the MMT system.

Although only two character encoding methods and two transmission methods are shown in FIG. 6, other encoding methods and transmission methods may be used. Also, the Profile ID does not need to consist only of the encoding method and the transmission method as shown in FIG. 6, and may be combined with other information. The other information is, for example, the video encoding method, resolution, frame rate, and the like of the content.

Returning to FIG. 5, the accompanying information generating unit 15 generates ARIB. OR. A Profile ID is set in the JP_PN parameter, and the Profile ID is output to the transmitting/receiving section 110 as content management information. The content management information is transmitted from the transmitter/receiver 110 to the client 20 as a profile signal (step S53). The server 10 receives information from the client 20 as to whether or not the client 20 can support the character encoding method transmitted by the profile signal (S53A). As a result of checking the information received from the client 20, the server 10, if the character encoding methods do not match between the two, for example, causes the display output unit 13 of the server 10 to display characters such as "not displayable". , the user is notified by outputting voice or the like from a speaker (NO in step S54, step S55). Note that if the server 10 and the client 20 can support a plurality of encoding methods, they may be adjusted to match the encoding method. On the other hand, the case where the character encoding methods that can be used by the server 10 and the client 20 match will be described below (YES in step S54). When the broadcast signal receiving unit 11 and the storage unit 13 have encoded content data to be transmitted, the broadcast signal receiving unit 11 and the storage unit 13 input the encoded content data to the content stream generation unit 18 . The content stream generation unit 18 generates a content stream from the input encoded content data (YES in step S56, step S57). The generated content stream is transmitted as a content stream signal from the transmitting/receiving section 110 (step S58). When there is no more encoded content data, the process ends (NO in step S56).

FIG. 7A is a flowchart showing an example of processing operations of a client according to the embodiment;

The client 20 establishes a communication path with the server 10 in server/client communication (step S70). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 . The transmitter/receiver 21 of the client 20 receives the profile signal transmitted by the server 10 (step S71). The transmitting/receiving unit 21 outputs the Profile ID extracted from the received profile signal to the analysis unit 25, and the analysis unit 25 analyzes the Profile ID (step S72). Specifically, in step S<b>72 , the analysis unit 25 recognizes the character encoding method corresponding to the Profile ID, and outputs the recognized character encoding method to the control unit 22 . The control unit 22 checks whether the input character encoding method is a character encoding method that can be processed by the client 20 (step S73). If the two match, the control unit 22 determines that the character encoding methods of the server 10 and the client 20 match. Then, the transmission/reception unit 21 and the content stream processing unit 23 are caused to execute processing (YES in step S73, S73A). Upon receiving the content stream signal, the transmission/reception unit 21 performs necessary processing such as demodulation, and outputs the content stream (YES in step S74). The output content stream is input to the content stream processing unit 23, processed by the content stream processing unit 23, and content data is obtained (step S75). The acquired content data is output to the display output unit 24, and video, audio, and character data are output from the display output unit 24 (step S76). When the transmitting/receiving unit 21 no longer receives the content stream signal, the processing is terminated (NO in step S74).

Further, in step S73, when the control unit 22 determines that the client 20 cannot support the character encoding method used by the server 10, the server 10 is informed, for example, that the character encoding method of the server 10 is "not compatible". The determination result is transmitted (step S73B), and an alarm is notified to the user by displaying characters such as "display not possible" on the display output unit 24 or by outputting voice or the like from a speaker (step S77).
An operation example of the second system will be described below with reference to FIGS. 5B and 7B.
In this operation example, the client 20 executes a "content transmission request" to the server 10, the client 20 confirms the information on the character encoding method in the media format profile transmitted by the server 10, and then transmits the confirmation result to the server 10. This is an example when no reply (ACK transmission) is made.
FIG. 5B is a flow chart showing an example of the processing operation of the server according to the second embodiment, but the description of the same processing parts as in FIG. 5A will be omitted.
The server 10 establishes a communication path with the client 20 in server/client communication (step S500). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 .
When the client 20 executes a "content transmission request" to the server 10 and the server 10 detects the "content transmission request" (YES in step S501), the server 10 transmits the requested content as in S52 and S53 of FIG. 5A. Data analysis processing is executed (step S502), and content management information including the content-associated information extracted by the analysis processing is transmitted from the transmission/reception unit 110 to the client 20 as a profile signal (step S503).
In the second system operation example of the present embodiment, the client 20 does not return the confirmation result to the server 10 even if it confirms the information on the character encoding method sent by the server 10 . If the character encoding method sent from is compatible, it sends a "content stream transmission request". When the server 10 receives a "content stream transmission request" from the client 20, the server 10 determines that the client 20 can receive the content, performs content stream generation processing, and transmits the content stream signal. (YES in step S504, S505, S506). On the other hand, if the server 10 does not receive a "content stream transmission request" from the client 20, the server 10 determines that the client 20 cannot receive the content, and stops processing (NO in step S504).
FIG. 7B is a flow chart showing an example of the processing operation of the client according to the second embodiment, but the description of the processing parts equivalent to those in FIG. 7A will be omitted.
The client 20 establishes a communication path with the server 10 in server/client communication (step S700). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 .
The client 20 transmits a "content transmission request" to the server 10 (step S701). As in steps S71 and S72 in FIG. 7A, the transmitting/receiving unit 21 of the client 20 receives the profile signal transmitted by the server 10, outputs the Profile ID extracted from the received profile signal to the analysis unit 25, and the analysis unit 25 , the server 10 recognizes the character encoding method of the content to be output (steps S701 and S702). The analysis unit 25 outputs the recognized character encoding method to the control unit 22, and the control unit 22 confirms whether the input character encoding method is a character encoding method that can be processed by the client 20 (step S703). . As a result of checking, if the control unit 22 determines that the character encoding method can be processed, it transmits a "content stream transmission request" to the server 10 (step S704A), and YES in steps S74, S75, and S76 in FIG. 7A. , the transmitting/receiving unit 21 and the content stream processing unit 23 are caused to process the content stream signal and the content stream to acquire the content data (YES in step S705, S706). The acquired content data is output as video, audio, and character data in the display output unit 24 (step S707). When the transmitting/receiving unit 21 no longer receives the content stream signal, the processing ends (NO in step S705).
If the control unit 22 determines in step S704 that the client 20 cannot support the character encoding method used by the server 10, the process ends (NO in step S704). At this time, an alarm may be notified to the user by displaying characters such as "display not possible" on the display output unit 24, or by outputting voice or the like from a speaker.

As described above, in this embodiment, the server 10 notifies the client 20 of the character encoding method of the encoded character data transmitted by the server 10 separately from the content stream, so that the client 20 can detect garbled characters in the character content. Content data can be used without causing According to this embodiment, it is also possible for the server 10 to transmit character content to the client 20 without converting the character encoding method.

In addition, in the present embodiment, since the server 10 only has to notify the character encoding method before transmitting the content data, it is possible to reduce the frequency of transmitting data other than the content data through communication.

(Third embodiment)
In this embodiment, an example is shown in which the server 10 includes information about the character encoding method in TS control information and SIT (Selection Information Table), which is program-related information, and transmits a content stream. The client 20 extracts the SIT from the received content stream, and obtains from the SIT information on the character encoding method of the character data transmitted by the server 10 .

An operation example of the system according to this embodiment will be described below.

FIG. 8 is a flow chart showing an example of the processing operation of the server according to this embodiment.
The server 10 establishes a communication path with the client 20 (step S80), and inputs the encoded content data from the broadcast signal receiving unit 11 or the storage unit 13 to the analysis unit 14 when there is a content data transmission request to the client 20. do. The analysis unit 14 analyzes the accompanying information of the encoded content data and extracts the character encoding method of the encoded character data (YES in step S81, step S82). The character encoding method of the encoded character data extracted by the analysis unit 14 is input to the accompanying information generation unit 15 . The accompanying information generation unit 15 generates content-related information based on the input character encoding method (step S83). This embodiment specifically uses SIT disclosed in ARIB standard ARIB STD-B21 as the content-related information.

FIG. 9 is a diagram showing an example of the configuration of the SIT transmitted by the server in the same embodiment.

A reserved area 91 and a reserved area 93 are currently not defined as reserved future use. Descriptor area 92 and descriptor area 94 are areas in which descriptors having data structures are placed.

In this embodiment, information about the character encoding method of character data is arranged in one of reserved area 91 , reserved area 93 , descriptor area 92 , and descriptor area 94 . When arranging in the reserved area 91 or reserved area 93, the position of the area is set as "character encoding method identification information" instead of the reserved area. For example, if the character encoding method is UTF-8, the character encoding method 0 is set to the information identifier, and 1 is set to the character encoding system information identifier in the case of an 8-bit code. When character encoding information is placed in the descriptor area 92 or descriptor area 94, a descriptor having a descriptor data structure and containing information about the character encoding, for example, a "character encoding information description child” and placed in descriptor area 92 or descriptor area 94. For the character encoding system information included in the descriptor, for example, a value of 0 is set when the character encoding system is UTF-8, and a value of 1 is set when the character encoding system is an 8-bit code.

Returning to FIG. 8, the content stream generator 18 generates a content stream including the SIT generated by the accompanying information generator 15 (step S84). When content protection is required for the generated content stream, the content protection unit 19 performs content protection processing on the content stream generated by the content stream generation unit 18, and outputs the protected content stream to the transmission/reception unit 110. (YES in step S85, step S86). If content protection is not required, the content stream generation unit 18 outputs the generated content stream to the transmission/reception unit 110 (NO in step S85). The transmitting/receiving unit 110 transmits the content stream or protected content stream to the client 20 as a content stream signal (step S87). In the server 10, when there is no content transmission request due to completion of transmission to the end of the content or detection of a signal such as "content transmission stop", the process ends (NO in step S81).

FIG. 10 is a flowchart showing an example of processing operations of a client according to the embodiment;

The client 20 establishes a communication path with the server 10 in server/client communication (step S100). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 . Upon receiving the content stream signal, the transmission/reception unit 21 of the client 20 performs content stream signal processing, acquires a content stream or a protected content stream, and outputs it to the content stream processing unit 23 (YES in step S101, step S102). If the content protection is applied, the content stream processing unit 23 performs a process of canceling the content protection on the protected content stream to obtain the content stream (YES in step S103, step S104). If content protection is not applied, the transmission/reception unit 21 outputs the content stream to the content stream processing unit 23 (NO in step S103). Whether or not the content stream is content-protected depends on, for example, information exchanged when the server 10 and the client 20 establish a communication path. In that case, for example, the control unit 22 controls the content stream processing unit 23 based on the information whether to implement content protection.

The content stream processing unit 23 performs demultiplexing (separation) processing on the content stream, and acquires SIT and encoded content data (step S105). The analysis unit 25 extracts the character encoding system information identifier specified in step S83 of FIG. 8 from the acquired SIT, and detects the character encoding system of the character data contained in the received encoded content data ( step S106). The content stream processing unit 23 decodes the encoded content data to obtain content data. In this embodiment, the encoded character data is decoded by the character encoding method of the character data detected by the analysis unit 25 to obtain the character data (step S107). The acquired content data including character data is output to the display output unit 24, and the display output unit 24 outputs video, audio, character data, etc. in a form that can be viewed by the user (step S108). Further, in step S106, if the content stream processing unit 23 cannot support the character encoding method detected by the analyzing unit 25, the processing of the character data is stopped, and the character data is not output to the display output unit 24. When the transmitting/receiving unit 21 stops receiving the content stream signal, the client 20 ends the process (NO in step S101).

As described above, in the present embodiment, the server 10 transmits the content stream to the client 20 by including the character encoding method of the encoded character data transmitted by the server 10 in the SIT. Content data can be used without garbled characters. According to this embodiment, it is also possible for the server 10 to transmit character content to the client 20 without converting the character encoding method.

In addition, in the present embodiment, the information on the character encoding method can be transmitted even while the server 10 is transmitting the content data. Even in such a case, the server 10 can notify the client 20 of the information of the changed character encoding method by SIT, and the client 20 can use the content data without garbled character content.

(Fourth embodiment)
This embodiment shows an example in which information about a character encoding method is included in a CMI (Content Management Information) packet, which is protection management information, when content protection processing by DTCP2 is applied to a content stream.

An operation example of the system according to this embodiment will be described below.

The server 10 has established a communication path with the client 20 and is requested to send content. Moreover, the server 10 and the client 20 according to the present embodiment are compatible with DTCP2, and the client 20 recognizes that the server 10 will transmit the content data in accordance with DTCP2 at the time of establishing the communication path.

FIG. 11 is a flow chart showing an example of the processing operation of the server according to this embodiment.

The server 10 establishes a communication channel with the client 20 in server/client communication (step S110). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 .
In the server 10 , when there is a content data transmission request to the client 20 , the control section 17 causes the broadcast signal receiving section 11 or the storage section 13 to output the encoded content data to the analysis section 14 . The analysis unit 14 analyzes the accompanying information of the encoded content data and extracts the character encoding method of the encoded character data (YES in step S111, step S112). The character encoding method of the encoded character data extracted by the analysis unit 14 is input to the accompanying information generation unit 15 . The accompanying information generation unit 15 generates content-related information based on the encoding method of the input encoded character data (step S113). Specifically, the content-related information in this embodiment is placed in a CMI packet disclosed in the DTCP2 specification (DTCP2 Volume 1 Specification), which is a content protection standard.

FIG. 12A is a diagram showing an example of protection management information transmitted by the server in the same embodiment, showing the configuration of a CMI packet. A CMI packet consists of a Header and a Body. Header and Body are indicated as 8-bit bit data rows, Header indicates information about a CMI packet to be transmitted, and Body indicates CMI, ie, protection management information, as CMI Field.

FIG. 12B is a diagram showing an example of a field of protection management information transmitted by the server in the same embodiment, showing a configuration example of the Body portion of FIG. 12A, that is, the CMI Field. An example of arranging two CMI Descriptors, X and Y, in the CMI Field is shown.

FIG. 12C is a diagram showing an example of a descriptor to be written in the field of protection management information transmitted by the server in the same embodiment, showing the contents of the CMI Descriptor in FIG. 12B.

This embodiment shows an example in which the CMI Descriptor of FIG. 12C is arranged in the field 12B1 of FIG. 12B. Field 12B1 is located in field 12A1 of FIG. 12A. Also, as an identifier indicating character encoding method information, for example, Char_encode_type is defined and placed in field 12C1 in FIG. 12C.

As for the encoding method and the value set in the identifier Char_encode_type, for example, if the encoding method is UTF-8, Char_encode_type is set to 0000, and if it is an 8-bit code, Char_encode_type is set to 0001.

Returning to FIG. 11, the content stream generator 18 generates a content stream from the encoded content data (step S114). The content protection unit 19 encrypts the content stream input from the content stream generation unit 18 by a method defined by DTCP2 to generate a PCP (Protected Content Packet), and generates a protected content packet (PCP) together with the CMI packet generated in step S113. It is output to the transmitting/receiving unit 110 as a content stream (step S115). CMI packets are not encrypted. The transmitting/receiving unit 110 transmits the protected content stream as a content stream signal to the client 20 (step S116). When there is no encoded content data to be transmitted from the broadcast signal receiving unit 11 or the storage unit 13, the server 10 ends the process (NO in step S111).

FIG. 13 is a flowchart showing an example of processing operations of a client according to the embodiment;

The client 20 establishes a communication path with the server 10 in server/client communication (step S130). When the communication path is established, the server 10 and the client 20 communicate via the transmitter/receiver 110 and the transmitter/receiver 21 .
Upon receiving the content stream signal, the transmission/reception unit 21 of the client 20 processes the content stream signal to obtain a protected content stream, outputs the CMI packet to the analysis unit 25, and outputs the PCP to the content stream processing unit 23 ( YES in step S131, step S132). The analysis unit 25 detects the setting value of Char_encode_type set by the server 10 in step S<b>113 from the CMI packet, and outputs the detected setting value to the control unit 22 . On the other hand, the content stream processing unit 23 performs a process of canceling content protection for the PCP, and obtains a content stream (step S134). The control unit 22 checks whether the client 20 supports the character encoding method corresponding to the input setting value of Char_encode_type (step S135). After confirming that the client 20 supports the character encoding method corresponding to the setting value of Char_encode_type, the control unit 22 instructs the content stream processing unit 23 to select the character encoding method corresponding to the setting value of Char_encode_type. is used to process the content stream (YES in step S135). The content stream processing unit 23 decodes the encoded content data extracted from the content stream to obtain content data. In this embodiment, the encoded character data is decoded by the character encoding method designated by the control unit 22 to obtain the character data (step S136). The acquired content data including character data is output to the display output unit 24, and the display output unit 24 outputs video, audio, character data, etc. in a form that can be viewed by the user (step S137). The client 20 ends the process when it stops receiving the content stream signal (NO in step S131).

Further, in step S135, if the content stream processing unit 23 cannot support the character encoding method detected by the analysis unit 25, the processing of the character data is stopped, and the character data is not output to the display output unit 24 (step S135). NO in S135).

As described above, in this embodiment, the client 20 can use the content data without garbled character content by notifying the character encoding method of the encoded character data transmitted by the server 10 by using the CMI packet. becomes. According to this embodiment, it is also possible for the server 10 to transmit character content to the client 20 without converting the character encoding method.

In particular, since the CMI packet is transmitted every time there is a change in the content described in the CMI packet, the character encoding method can be quickly detected even in the content data whose character encoding method frequently changes to some extent. It is possible.

According to at least one embodiment described above, it is possible to provide a content transmission device and a transmission method that make it possible to use character content without garbled characters.
It goes without saying that the first, second, third, and fourth embodiments may be combined with any other embodiment. In addition, the user may set or switch between enabling and disabling of functions according to any embodiment, that is, switching between combinations of embodiments.

The gist of the system described above can also be described as follows.
(A1) first broadcast receiving means for receiving a first broadcast (new 4K8K satellite broadcast) using a first character encoding method;
a second broadcast receiving means for receiving a second broadcast (preceding three waves) using a second character encoding method;
analysis means for determining a character encoding method used in video content received by the first broadcast receiving means or the second broadcast receiving means;
the first character encoding method, the second character encoding method, or the first character encoding method as the character encoding method used in the video content based on the determination result of the analyzing means; Character data conversion means for converting into a third character encoding method, which is a character encoding method other than the second character encoding method;
and a transmitting means conforming to the DLNA (registered trademark) standard for transmitting a video content signal containing video content whose character encoding system has been converted by said character data converting means.
(A1-1)
The video content transmission device according to (A1), wherein the video content received by the first broadcast reception means or the second broadcast reception means is directly input to the analysis unit.
(A1-2)
(A1) comprising storage means for storing video content received by said first broadcast receiving means or said second broadcast receiving means, wherein said analysis means receives as input the video content stored in said storage means; Content transmission device as described.
(A2) first broadcast receiving means for receiving a first broadcast (new 4K8K satellite broadcast) using a first character encoding method;
a second broadcast receiving means for receiving a second broadcast (preceding three waves) using a second character encoding method;
analysis means for determining a character encoding method used in video content received by the first broadcast receiving means or the second broadcast receiving means;
Accompanying information addition means for adding information indicating a character encoding method used in the video content to the video content as content management information based on the determination result of the analysis device;
and a transmitting means conforming to the DLNA (registered trademark) standard for transmitting the video content to which the content management information has been added by the incidental information adding means.
(A2-1) The video content transmitting apparatus according to (A2), wherein the video content received by the first broadcast receiving means or the second broadcast receiving means is directly input to the analyzing means.
(A2-2)
Storing means for storing the video content received by the first broadcast receiving means or the second broadcast receiving means is provided, and the analyzing means receives the video content stored in the storing means (A2) Content transmission device as described.
(A2-2-1)
When the video content received by the first broadcast receiving means or the second broadcast receiving means is stored in the storage means, the character encoding method used in the received video content is The content transmission device (A2-2-2) according to (A2-2), which converts to a character encoding method other than the character encoding method used and stores the content
combining the video content received by the first broadcast receiving means and the video content received by the second broadcast receiving means into one video content, and storing the combined video content in the storage means; A2-2) or the content transmission device according to (A-2-2) (A3), wherein the content management information added by the incidental information adding means is in a DLNA (registered trademark) media format transmitted by the transmitting means The video content transmission device according to (A2), (A2-1), (A2-2), (A2-2-1), and (A2-2-2), which is arranged in a profile.
(A4) The content management information added by the accompanying information adding means is arranged in an SIT conforming to the MPEG-2 TS format included in the video content signal transmitted by the transmitting means (A2). , (A2-1), (A2-2), (A2-2-1), and (A2-2-2).
(A5) The video content transmission device has content protection means conforming to the DTCP2 standard, and the content management information added by the incidental information addition means is arranged in a CMI packet generated by the content protection means. The video content transmission device according to (A2), (A2-1), (A2-2), (A2-2-1), and (A2-2-2) characterized by
While several embodiments of the invention have been described, these embodiments have been presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and equivalents thereof. Furthermore, in each constituent element of the claims, even if the constituent element is divided and expressed, a plurality of constituent elements are expressed together, or a combination of these is expressed, it is within the scope of the present invention. Moreover, a plurality of embodiments may be combined, and examples configured by such combinations are also within the scope of the invention.

Also, in order to make the description clearer, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual mode. In the block diagram, data and signals may be exchanged between unconnected blocks, or between connected blocks in directions not indicated by arrows. The processing shown in the flowchart may be realized by hardware (such as an IC chip), software (such as a program), or a combination of hardware and software. In addition, when the claims are expressed as control logic, when expressed as a program including instructions for executing a computer, and when expressed as a computer-readable recording medium in which the instructions are written, the apparatus of the present invention is applied. be. Also, the names and terms used are not limited, and other expressions are included in the present invention as long as they have substantially the same content and the same meaning.

DESCRIPTION OF SYMBOLS 10... Server, 11... Broadcast signal receiver, 12... Display output part, 13... Storage part, 14... Analysis part, 15... Accompanying information generation part, 16... Character data conversion unit 17 Control unit 18 Content stream generation unit 19 Content protection unit 20 Client 21 Transmission/reception unit 22 Control unit 23 . . . content stream processing unit, 24 .. display output unit, 25 .

Claims (10)

first encoded content data obtained by encoding content data including at least character data transmitted by a broadcast signal and first content accompanying information accompanying the first encoded content data; encoded content data input/output means for outputting encoded second encoded content data and second content accompanying information accompanying said second encoded content data;
analysis means for analyzing the second content-associated information and extracting information on a character encoding method used in the second encoded content data;
a transmission unit for including the extracted information on the character encoding method in a DTCP2 standard CMI (Content Management Information) packet and transmitting the packet to the outside together with the second encoded content data. 2. The encoded content data input/output means inputs and outputs the first encoded content data and the first content accompanying information obtained by processing a broadcast signal transmitted according to the MPEG2 transport stream system. The content transmission device according to . 2. The encoded content data input/output means according to claim 1, wherein the encoded content data input/output means inputs/outputs the first encoded content data and the first content-accompanying information obtained by processing a broadcast signal broadcast by the MMT system. Content transmission device. The encoded content data input/output means stores the first encoded content data and the first content accompanying information transmitted by the broadcast signal, and stores the stored first encoded content data and the first content accompanying information. 2. The content transmitting apparatus according to claim 1, which outputs first content-associated information as said second encoded content data and said second content-associated information. 5. The content transmission device according to claim 4, wherein said broadcast signal is broadcast according to MPEG2 transport stream system. 5. The content transmission device according to claim 4, wherein the broadcast signal is broadcast according to the MMT system. The encoded content data input/output means converts at least part of the input first encoded content data into a character encoding method different from the first character encoding method used in the first encoded content data. 2. The content transmission device according to claim 1, wherein the encoded content data is stored as second encoded content data converted into the second character encoding method, and the second encoded content data is output. The stored second encoded content data is encoded by combining encoded content data transmitted by a broadcast signal according to the MPEG2 transport stream system and encoded content data transmitted by a broadcast signal according to the MMT system. 8. The content transmission device according to claim 7, which is content data. 9. The content transmission device according to any one of claims 1 to 8, wherein said transmission means conforms to the DLNA (registered trademark) standard. first encoded content data obtained by encoding content data including at least character data transmitted by a broadcast signal and first content accompanying information accompanying the first encoded content data; outputting the encoded second encoded content data and second content accompanying information accompanying the second encoded content data;
analyzing the second content-accompanying information and extracting information on a character encoding method used in the second encoded content data;
A content transmission method for including the extracted character encoding method in a DTCP2 standard CMI (Content Management Information) packet and transmitting it to the outside together with the second encoded content data.

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