JP7804121B2 - Content transmission device and transmission method - Google Patents

Description

The embodiment relates to a content transmission device and a transmission method.

Receivers for BS digital broadcasting, 110-degree CS digital broadcasting, and terrestrial digital broadcasting (hereinafter referred to as the three leading waves) can transmit the received broadcast content to a home IP (Internet Protocol) network. This content transmission is performed by the receiver acting as a DLNA (registered trademark) (Digital Living Network Alliance)-based content server (hereinafter referred to as the server), and the transmitted content is received by a DLNA-based content client (hereinafter referred to as the client) interconnected with the server via the home IP network. Note that content transmission requires the application of content protection technology defined as appropriate by each broadcasting standard. One example of such content protection technology is DTCP (Digital Transmission Content Protection).

In December 2018, new 4K/8K satellite broadcasting was launched, joining the three preceding waves. As with the receivers of the preceding three waves, receivers of the new 4K/8K satellite broadcasting can transmit received new 4K/8K satellite broadcasting content to a home IP network, provided that content protection technology is applied. Appropriate content protection technology is DTCP2 (Digital Transmission Control Protocol 2 (DTCP)).
Transmission Content Protection Two) is specified.
Some receivers for new 4K/8K satellite broadcasting are capable of receiving the three preceding waves (hereinafter referred to as "shared receivers"). In this case, the shared receiver functions as a server and can transmit the content of the new 4K/8K satellite broadcasting and the content of the three preceding waves to nearby clients via a home IP network.

By the way, the character encoding method used for the new 4K/8K satellite broadcasting content and the content of the three preceding waves is different. The former uses UTF-8, while the latter uses 8-bit encoding.

ARIB TR-B14 6.5 Edition "Digital Terrestrial Television Broadcasting Operational Guidelines" (Volume 4) ARIB TR-B15 7.1 Edition "BS/Broadband CS Digital Broadcasting Operational Guidelines" (Volume 1) ARIB STD-B21 5.10 edition "Digital Broadcasting Receiver Standard" ARIB TR-B39 1.7 Edition "Advanced Wideband Satellite Digital Broadcasting Operational Guidelines" (Volume 1) ARIB STD-B60 1.12 Edition "Standard for Advanced Wideband Satellite Digital Broadcasting Receivers" ARIB STD-B62 Version 1.9 "Multimedia Coding Method for Digital Broadcasting (Second Generation)" (Volume 1) ARIB STD-B63 1.7 Edition "Standard for Advanced Wideband Satellite Digital Broadcasting Receivers"

However, the relevant standards and operational regulations do not specify a field to be placed within content data to indicate the character encoding used in the content, and clients receiving content have no way of knowing the character encoding used in the content sent from the server. This means that clients may incorrectly process the character data contained in the content, resulting in malfunctions such as displaying characters different from those intended (hereinafter referred to as garbled characters). In particular, if the server has recording or content editing functions, it is expected that the character encoding will be converted when recording content to a recording medium, or multiple pieces of content with different character encodings will be combined to reconstruct a single piece of content, and there is a high possibility that garbled characters will occur when such content is received by a client.

The problem that this invention aims to solve is to provide a content transmission device and transmission method that enables the use of character data within content without garbling.

According to one embodiment, an encoded content data input/output means receives first encoded content data obtained by encoding content data including at least character data transmitted by a broadcast signal and first content associated information associated with the first encoded content data, and outputs second encoded content data obtained by encoding the content data and second content associated information associated with the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
Based on the information of the character encoding extracted by the analysis means, a character data conversion means for converting the first character encoding for the character data of the second encoded content data to output third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
Further, a content transmission device is provided that has a means for communicating with the external client, obtaining information on a second character encoding method that the client can handle, comparing the information on the first character encoding method for the character data in the third encoded content data, and if the two match, inputting encoded content data containing encoded character data using the first character encoding method into a content stream generation unit, and if the two do not match, inputting the character data in the third encoded content data into the character data conversion means.

FIG. 1 is a block diagram illustrating an example of a functional configuration of a server according to an embodiment. FIG. 2 is a block diagram illustrating an example of the functional configuration of a client according to the embodiment. FIG. 3 is a flowchart illustrating an example of a processing operation of the server according to the first embodiment. FIG. 4 is a flowchart showing an example of a processing operation of a client according to the first embodiment. FIG. 5A is a flowchart showing an example of a processing operation of the server according to the second embodiment. FIG. 5B is a flowchart showing an example of a 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 a processing operation of a client according to the second embodiment. FIG. 7B is a flowchart showing an example of a processing operation of a client according to the second embodiment. FIG. 8 is a flowchart showing an example of a processing operation of the server according to the third embodiment. FIG. 9 is a diagram showing an example of the configuration of an SIT transmitted by a server in the third embodiment. FIG. 10 is a flowchart showing an example of a processing operation of a client according to the third embodiment. FIG. 11 is a flowchart showing an example of a processing operation of the server according to the fourth embodiment. FIG. 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 a server in the fourth embodiment. 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 flowchart showing an example of a processing operation of a client according to the fourth embodiment.

The following describes the embodiment with reference to the drawings.

Figure 1 is a block diagram showing an example of the functional configuration of a server according to an embodiment.

Server 10 is a shared receiver capable of receiving both content data transmitted by new 4K/8K satellite broadcasting and content data transmitted by the three preceding waves. It receives and processes broadcast signals, decodes and plays back the resulting content data, and displays and outputs it as video, audio, text, and other formats. Server 10 is, for example, a television receiver capable of viewing new 4K/8K satellite broadcasting and the three preceding waves. Typically, the character encoding method for text content transmitted by broadcast signals is uniquely determined by the type of broadcast signal. Therefore, as a shared receiver, server 10 is capable of decoding and playing back content corresponding to the character encoding method required for receiving broadcast signals. However, server 10 may also be equipped with encoding and decoding methods for character encoding methods other than the character encoding method required for receiving broadcast signals. Server 10 can also store content data or content data before decoding and playing back (hereinafter, when specifically distinguished, referred to as encoded content data) as digital data in storage unit 13. Server 10 can also output content data to an external device (client) using a network compliant with DLNA (registered trademark) or similar.

The broadcast signal receiving unit 11 receives broadcast signals via an antenna (not shown), acquires encoded content data, and outputs it as content data that can be output as video, audio, and text. The broadcast signal receiving unit 11 can also output intermediate data acquired from the received new 4K/8K satellite broadcasting signal or the broadcast signals of the three preceding waves before obtaining the content data. This intermediate data includes MMT/TLV streams and control information generated by the MPEG Media Transport method (hereinafter referred to as the MMT method) used in the new 4K/8K satellite broadcasting, transport streams and transmission control information generated by the MPEG-2 Transport Stream method (hereinafter referred to as the TS method) used in the three preceding waves, and program-related information. The broadcast signal receiving unit 11 can also perform appropriate conversions on the acquired content data and encoded content data and output them to the storage unit 13, etc., along with related control information, transmission control information, program-related information, etc. Normally, the broadcast type and the character encoding method for the character data transmitted by that broadcast match; however, for example, when the character encoding method for the character data in the encoded content data is converted when output to storage unit 13, the broadcast type and the character encoding method for the character data may not necessarily match in the data stored in storage unit 13. Furthermore, in the data stored in storage unit 13, multiple encoded content data with different character encoding methods may be combined, resulting in encoded content data containing multiple character data encoded using different character encoding methods.

The display output unit 12 is, for example, a monitor or speaker, which can output the content data output by the broadcast signal receiving unit 11 and storage unit 13 as video, audio, and text 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, such as a hard disk. The storage unit 13 can also output stored data. The storage unit 13 may also have a function for editing programs stored (recorded). In this case, it is possible to create a single piece of content by cutting and pasting or combining a 4K/8K program and a program from the three preceding waves. The storage unit 13 may store encoded content data that combines encoded content data transmitted in the three preceding waves with encoded content data transmitted in new 4K/8K satellite broadcasting. In this case, the encoding method for the combined encoded content data may be to re-encode the encoded content data portion of the new 4K/8K satellite broadcasting that was encoded using the MMT method into the MPEG2 TS method, thereby converting the entire data into the MPEG2 TS method, or to re-encode the encoded content data portion of the three preceding waves that was encoded using the MPEG2 TS method into the MMT method, thereby converting the entire data into the MMT method. Alternatively, both the encoded content data portion of the new 4K/8K satellite broadcast and the encoded content data portion of the three preceding waves may be converted to an encoding format other than the MPEG2 TS format or the MMT format, and this may be used as the encoding format for the combined encoded content data. Note that the function for editing saved (recorded) programs may be provided as a function within the server 10, rather than in the storage unit 13.

The analysis unit 14 analyzes the control information output by the broadcast signal receiving unit 11, the content data stored in the storage unit 13, or accompanying information associated with the encoded content data, and extracts content management information such as the character encoding method of the encoded character data (hereinafter referred to as encoded character data) that is part of the encoded content data.

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

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

The control unit 17 controls each function within the server 10. For example, it instructs the character data conversion unit 16 on whether or not to perform encoding conversion of encoded character data, and if so, the conversion method. In Figure 1, data may also be exchanged between function blocks that are not specifically connected to the control unit 17.

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

The content protection unit 19 performs content protection such as encryption on the content stream generated by the content stream generation unit 18. The technology used for content protection is, for example, DTCP (Digital Transmission Content Protocol).
This technology complies with standards such as DTCP (Digital Transmission 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, a digital copy control descriptor, a content usage control descriptor, etc.) included in the broadcast signal.

The transceiver 110 transmits the content-protected content stream (hereinafter referred to as the protected content stream) output by the content protection unit 19 to the client 20 as a content stream signal using a predetermined communication method. In this embodiment, the transceiver 110 uses a DLNA (registered trademark)-compliant IP communication method (hereinafter, when distinguishing from broadcast signal reception, this will be particularly referred to as server-client communication). Note that wireless is used as the communication medium for server-client communication, but this is not limited to wireless and wired communication may also be used. The server 10 can also output the unprotected content stream output by the content stream generator 18 as a content stream signal without going through the content protection unit 19. Whether to protect or not protect the content stream is selected by the control unit 17, for example, based on control information received by the broadcast signal receiver 11 (specifically, a digital copy control descriptor, a content usage control descriptor, etc.).

Figure 2 is a block diagram showing an example of the functional configuration of a client according to an embodiment.

Client 20 receives and processes the content stream signal transmitted by server 10, and displays and outputs video, audio, text data, etc. Client 20 is, for example, a television receiver, tablet, smartphone, etc. separate from server 10. Furthermore, client 20 does not necessarily have to be a receiver for new 4K8K satellite broadcasting or the three preceding waves. Furthermore, client 20 may be capable of processing both the character encoding method used in new 4K8K satellite broadcasting and the character encoding method used in the three preceding waves, or may be capable of processing only one of them.

The transceiver 21 is an interface capable of communicating with the transceiver 110 of the server 10, and receives and processes the content stream signal transmitted by the server 10 using a predetermined communication method, and outputs the content stream. In this embodiment, the transceiver 110 is equipped with a communication method using IP communication compliant with DLNA (registered trademark).

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

The content stream processing unit 23 performs content protection removal, demultiplexing (separation processing), decryption and playback, etc. on the content stream output by the transmission/reception unit 21 as necessary to extract the content data, and outputs the content data to the display output unit 24. The display output unit 24 displays and outputs the content data as video, audio, and text.

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

(First embodiment)
In this embodiment, the server 10 selects and converts 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. For example, if the client 20 can process the character data of the new 4K8K satellite broadcasting, the server 10 uses UTF-8 as the character encoding method, and if the client 20 can only process the preceding three waves, the server 10 uses an 8-bit code as the character encoding method. Below, an example of the operation of the system according to this embodiment will be described.

FIG. 3 is a flowchart showing an example of a 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 transmission/reception unit 110 and the transmission/reception unit 21. The control unit 17 obtains information from the client 20 about the character encoding method that the client 20 can process when establishing this communication path. Alternatively, instead of obtaining the information from the client 20, if the user knows in advance the character encoding method that the client 20 can process, for example, in the server 10, it may be possible to set the character encoding method of the character data to be sent to the client 20 from a remote control (not shown).

When the control unit 17 detects a request to send content data to the client 20, it inputs the encoded content data from the broadcast signal receiving unit 11 or the storage unit 13 to the analysis unit 14. The analysis unit 14 analyzes the content-associated information accompanying the encoded content data (YES in step S32, step S33). The content-associated information includes information related to the content, such as program information and data processing methods. In this embodiment, the analysis unit 14 extracts information about the character encoding method for the encoded character data from the content-associated information and inputs the extracted information about the character encoding method to the control unit 17. The control unit 17 compares the information about the character encoding method (hereinafter referred to as the first character encoding method) extracted by the analysis unit 14 with the information about the character encoding method (hereinafter referred to as the second character encoding method) that can be used by the client 20 obtained in step S31. If the comparison shows that the two match, the control unit 17 inputs the encoded content data including the encoded character data using the first character encoding method from the broadcast signal receiving unit 11 or 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 or the storage unit 13 to the character data conversion unit 16. The character data conversion unit 16 decodes and plays back the encoded character data of the encoded content data using the first character encoding method, and then encodes and outputs it again using the second character encoding method (step S35). For example, this corresponds to a case where the client 20 can only support the character encoding method of the three preceding waves and cannot support the character encoding method of the character content received by the new 4K8K satellite broadcasting received by the server 10.

In this embodiment, we have shown the case where the character encoding method (second character encoding method) that the client 20 can process is valid on the server 10, but if the second character encoding method is invalid on the server 10, it is also possible to notify the user of an alarm on the display output unit 13 of the server 10.

The content stream generator 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 standard or an MMT/TLV stream conforming to the MMT/TLV standard.

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

The transceiver 110 outputs the input content stream or protected content stream to the outside as a content stream signal using a predetermined communication method (step S39). For example, the transceiver 110 outputs IP communication data compliant with DLNA (registered trademark) as a wireless signal compliant with the Wi-Fi (registered trademark) system. When there are no more content transmission requests, the process ends (NO in step S32).

FIG. 4 is a flowchart showing an example of a processing operation of a client according to the embodiment.
The client 20 establishes a communication path with the server 10 for server-client communication (step S41). When the transceiver 21 receives a content stream signal, it performs necessary processing, such as demodulation, and outputs a content stream or a protected content stream (YES in step S42). The output content stream is input to the content stream processor 23, which processes it to obtain content data (step S43). The content stream processor 23 also performs content protection removal processing on the protected content stream and obtains content data from the obtained content stream. The obtained content data is output to the display output unit 24, where it is displayed and output as video, audio, and text data (step S44). When the client 20 no longer receives the content stream signal (NO in step S42), it terminates the process.

In this embodiment, the server 10 analyzes the encoded content data to be sent to the client 20, and if the character encoding used is not valid for the client 20, the server 10 converts it to a character encoding that is valid for the client 20 and sends the encoded content data, allowing the client 20 to use the content data without garbling the character content.

Furthermore, when a receiver for new 4K/8K satellite broadcasting and the three preceding waves serves as a server (DMS in DLNA (registered trademark)) with content transmission capabilities, the content sent to the client (DMR/DMP in DLNA (registered trademark)) may include both new 4K/8K satellite broadcasting programs and programs from the three preceding waves, and therefore, unless special conversion is performed, the character encoding method for the character information may be UTF-8 or 8-bit code. In such cases, garbled characters will occur if character data is received using a character encoding method that is not valid for the client 20. Furthermore, character encoding methods are not limited to UTF-8 and 8-bit code; similar problems will occur with other character encoding methods. According to this embodiment, the server 10 converts the character data into a character encoding method that is valid for the client 20, allowing the client 20 to use the content data without garbling the character content.

Furthermore, whether the server 10 is a receiver compatible with the new 4K/8K satellite broadcasting and a receiver compatible with the three preceding waves does not limit whether the server 10 can process UTF-8 or 8-bit codes. For example, even if the server 10 is a receiver compatible with only the three preceding waves, as long as it can process multiple character encoding methods, this embodiment allows the server 10 to provide the client 20 with content data that does not cause garbled characters.

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

The method according to this embodiment is a method of putting character encoding information into a DLNA (registered trademark) media format profile (hereinafter simply referred to as the profile). Two operation examples are shown, depending on the method of "content transmission request" that triggers the server 10 to transmit content, and the processing method when confirming the character encoding information in the media format profile of the client 20.

The first example, using Figures 5A and 7A, shows a case where a user issues a "content transmission request" to the server 10 by operating the remote control, and the client 20 checks the character encoding information in the media format profile, and then returns (sends an ACK) to the server 10 with information on whether the confirmed character encoding is compatible.

The second example, using Figures 5B and 7B, shows a case where the client 20 issues a "content transmission request" to the server 10, and after checking the character encoding information in the media format profile, the client 20 does not return the confirmation result to the server 10 (sends an ACK). Below, we will explain an example of the operation of the first system.

Figure 5A is a flowchart 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 for server-client communication (step S50). Once the communication path is established, the server 10 and the client 20 communicate via the transceiver units 110 and 21. When a user issues a "content transmission request" to the server 10 by operating a remote control or the like, and a request to transmit content data is generated in the server 10, the analysis unit 14 performs an analysis process on 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 associated information. The character encoding method of the encoded character data extracted by the analysis unit 14 is input to the associated information generation unit 15. The associated information generation unit 15 generates content management information in accordance with the specifications from the character encoding method of the input encoded character data. For example, this content management information is, but is not limited to, the parameter indicated by ARIB.OR.JP_PN (hereinafter referred to as the ARIB.OR.JP_PN parameter) placed in the fourth field of protocolInfo described in the ARIB standard ARIB STD-B21. protocolInfo is a property described in a DIDL-Lite document, which is an XML document exchanged over a network compliant with DLNA (registered trademark), but the content management information may also be placed in another property, element, etc. within the same document.

Figure 6 shows an example of parameters sent by the server in this embodiment.

This parameter indicates the profile related to the content data sent by the server 10, and is specifically referred to as a 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 format.

No.2: TS_JP_8UNIT
It contains character data coded with 8-bit codes and is transmitted in a content stream conforming to the TS format.

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

No.4: TS_JP_8UNIT
It contains character data encoded with 8-bit codes and is transmitted in a content stream conforming to the MMT method.

Note that Figure 6 only shows two character encoding methods and two transmission methods, but other encoding methods and transmission methods may also be used. Furthermore, the Profile ID does not have to consist of only the encoding method and transmission method as shown in Figure 6, but may also be combined with other information. Examples of other information include the encoding method, resolution, and frame rate of the content's video.

Returning to FIG. 5, in the associated information generation unit 15, the Profile ID is set in the ARIB.OR.JP_PN parameter based on the transmission method and character encoding method used by the server 10, and the Profile ID is output to the transmission/reception unit 110 as content management information. The content management information is transmitted from the transmission/reception unit 110 to the client 20 as a profile signal (step S53). The server 10 receives information from the client 20 about whether the client 20 can support the character encoding method transmitted in the profile signal (S53A). If the server 10 confirms the information received from the client 20 and the character encoding methods do not match, the server 10 notifies the user by, for example, displaying text such as "Not Displayable" on the display output unit 13 of the server 10 or outputting a sound or other message through a speaker (NO in step S54, step S55). Note that if the server 10 and the client 20 are compatible with multiple encoding methods, they may be adjusted to match the encoding methods of the two. On the other hand, the following describes the case where the character encoding methods that the server 10 and client 20 can use match (YES in step S54). If the broadcast signal receiving unit 11 or the storage unit 13 has encoded content data to transmit, the broadcast signal receiving unit 11 or the storage unit 13 inputs the encoded content data to the content stream generating unit 18. The content stream generating 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 unit 110 (step S58). When there is no more encoded content data, the process ends (NO in step S56).

Figure 7A is a flowchart showing an example of a client's processing operation according to this embodiment.

The client 20 establishes a communication path with the server 10 in server/client communication (step S70). Once the communication path is established, the server 10 and the client 20 communicate via the transmission/reception unit 110 and the transmission/reception unit 21. In the client 20, the transmission/reception unit 21 receives the profile signal sent by the server 10 (step S71). The transmission/reception 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 S72, the analysis unit 25 recognizes the character encoding corresponding to the Profile ID and outputs the recognized character encoding to the control unit 22. The control unit 22 checks whether the input character encoding is a character encoding that can be processed by the client 20 (step S73). If the two match, the control unit 22 determines that the character encodings of the server 10 and the client 20 match, and returns a determination result such as "compatible" to the server 10, causing the transceiver 21 and the content stream processing unit 23 to execute processing (YES in step S73, S73A). When the transceiver 21 receives the content stream signal, it 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 acquired (step S75). The acquired content data is output to the display output unit 24, and video, audio, and character data are output by the display output unit 24 (step S76). When the transceiver 21 no longer receives the content stream signal, the processing ends (NO in step S74).

Also, if the control unit 22 determines in step S73 that the client 20 is incompatible with the character encoding method used by the server 10, it sends a determination result to the server 10, such as "incompatible" with the server 10's character encoding method (step S73B), and notifies the user of the alarm by having the display output unit 24 display text such as "display not possible" or by outputting a sound via the speaker (step S77).

Below, an example of the operation of the second system is explained using Figures 5B and 7B.

This operation example is an example in which the client 20 issues a "content transmission request" to the server 10, and after checking the character encoding information in the media format profile sent by the server 10, the client 20 does not return the confirmation result to the server 10 (sends an ACK).

Figure 5B is a flowchart showing an example of the processing operation of the server according to the second embodiment, but a description of the processing equivalent to that in Figure 5A will be omitted.

The server 10 establishes a communication path with the client 20 for server/client communication (step S500). Once the communication path is established, the server 10 and client 20 communicate via the transceiver units 110 and 21.

When the client 20 issues a "content transmission request" to the server 10 and the server 10 detects the "content transmission request" (YES in step S501), the server 10 executes an analysis process of the requested content data (step S502), similar to steps S52 and S53 in FIG. 5A, and transmits content management information, including content-related information extracted by the analysis process, from the transmitter/receiver 110 to the client 20 as a profile signal (step S503).

In the second system operation example of this embodiment, even if the client 20 checks the character encoding information sent by the server 10, it does not return the confirmation result to the server 10. However, if the client 20 can handle the character encoding sent from the server 10, it sends a "content stream transmission request." When the server 10 receives a "content stream transmission request" from the client 20, it determines that the client 20 can receive the content, performs content stream generation processing, and transmits it as a content stream signal (YES in steps S504, S505, S506). On the other hand, if the server 10 does not receive a "content stream transmission request" from the client 20, it determines that the client 20 cannot receive the content and stops processing (NO in step S504).

Figure 7B is a flowchart showing an example of the processing operation of a client according to the second embodiment, but a description of the processing equivalent to that in Figure 7A will be omitted.

The client 20 establishes a communication path with the server 10 for server/client communication (step S700). Once the communication path is established, the server 10 and client 20 communicate via the transceiver units 110 and 21.

The client 20 sends a "content transmission request" to the server 10 (step S701). As in steps S71 and S72 of FIG. 7A, the transceiver 21 in the client 20 receives the profile signal sent by the server 10 and outputs the Profile ID extracted from the received profile signal to the analysis unit 25. The analysis unit 25 recognizes the character encoding of the content that the server 10 is to output (steps S701 and S702). The analysis unit 25 outputs the recognized character encoding to the control unit 22, and the control unit 22 checks whether the input character encoding is a character encoding that can be processed by the client 20 (step S703). If the control unit 22 determines that the character encoding can be processed as a result of the check, it sends a "content stream transmission request" to the server 10 (step S704A), and similar to steps S74 YES, S75, and S76 of FIG. 7A, causes the transceiver unit 21 and content stream processing unit 23 to process the content stream signal and content stream, and acquires content data (steps S705 YES, S706). The acquired content data is output as video, audio, and character data by the display output unit 24 (step S707). When the transceiver unit 21 no longer receives the content stream signal, the processing ends (step S705 NO).

Also, in step S704, if the control unit 22 determines 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, the display output unit 24 may display text such as "Display not possible" or output a sound via the speaker to notify the user of this.

In this way, in this embodiment, the server 10 notifies the client 20 of the character encoding method of the encoded character data that the server 10 sends separately from the content stream, allowing the client 20 to use the content data without garbling the character content. According to this embodiment, the server 10 can also send character content to the client 20 without converting the character encoding method.

Furthermore, in this embodiment, the server 10 only needs to notify the user of the character encoding method before sending the content data, thereby reducing the frequency of sending data other than content data via communication.

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

Below, we will explain an example of the operation of the system related to this embodiment.

Figure 8 is a flowchart 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 when there is a request to send content data to the client 20, it inputs the encoded content data from the broadcast signal receiving unit 11 or the storage unit 13 to the analysis unit 14. The analysis unit 14 performs an analysis process on 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). In this embodiment, the content-related information specifically uses the SIT disclosed in ARIB STD-B21 of the ARIB standard.

Figure 9 shows an example of the configuration of an SIT transmitted by the server in this embodiment.

Reserved areas 91 and 93 are reserved for future use and are not currently defined. Descriptor areas 92 and 94 are areas where descriptors with data structures are placed.

In this embodiment, information about the character encoding method of character data is placed in either reserved area 91, reserved area 93, descriptor area 92, or descriptor area 94. When placed in reserved area 91 or reserved area 93, the positioning of the area is not a reserved area, but for example, "character encoding identification information". For example, if the character encoding method is UTF-8, the character encoding method information identifier is set to 0, and if it is an 8-bit code, the character encoding method information identifier is set to 1. When placing character encoding information in descriptor area 92 or descriptor area 94, a descriptor that has a descriptor data structure and contains information about the character encoding method, for example, a "character encoding information descriptor", is defined and placed in descriptor area 92 or descriptor area 94. The character encoding method information included in the descriptor is, for example, set to 0 if the character encoding method is UTF-8, and set to 1 if it is an 8-bit code.

Returning to FIG. 8 , the content stream generation unit 18 generates a content stream including the SIT generated by the associated information generation unit 15 (step S84). If 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 transceiver 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 transceiver unit 110 (NO in step S85). The transceiver unit 110 transmits the content stream or protected content stream to the client 20 as a content stream signal (step S87). If the server 10 has finished transmitting the content up to the end or has detected a signal such as "stop content transmission," and there is no longer a content transmission request, the process ends (NO in step S81).

Figure 10 is a flowchart showing an example of a client's processing operation according to this embodiment.

The client 20 establishes a communication path with the server 10 for server-client communication (step S100). Once the communication path is established, the server 10 and client 20 communicate via the transceiver 110 and transceiver 21. When the transceiver 21 of the client 20 receives a content stream signal, it processes the content stream signal to obtain a content stream or a protected content stream, and outputs the resulting stream to the content stream processing unit 23 (YES in step S101, step S102). If content protection is applied, the content stream processing unit 23 removes content protection from the protected content stream to obtain a content stream (YES in step S103, step S104). If content protection is not applied, the transceiver 21 outputs the content stream to the content stream processing unit 23 (NO in step S103). Whether the content stream is content protected is determined, for example, by information exchanged when the server 10 and client 20 establish a communication path. In this case, for example, the control unit 22 controls the content stream processing unit 23 to implement or disable content protection based on that information.

The content stream processing unit 23 performs demultiplexing (separation) processing on the content stream to obtain the SIT and encoded content data (step S105). The analysis unit 25 extracts the character encoding information identifier specified in step S83 of FIG. 8 from the obtained SIT and detects the character encoding of the character data included 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 analysis unit 25 decodes the encoded character data using the character encoding method of the character data detected to obtain the character data (step S107). The obtained content data, including the character data, is output to the display output unit 24, which outputs video, audio, character data, etc. in a format that the user can view (step S108). Also, if the content stream processing unit 23 cannot support the character encoding detected by the analysis unit 25 in step S106, it stops processing the character data and does not output the character data to the display output unit 24. When the content stream signal is no longer received by the transmitter/receiver 21, the client 20 ends the process (NO in step S101).

In this way, in this embodiment, the server 10 sends a content stream to the client 20 by including the character encoding method of the encoded character data sent by the server 10 in the SIT, allowing the client 20 to use the content data without garbling the character content. According to this embodiment, the server 10 can also send character content to the client 20 without converting the character encoding method.

In addition, in this embodiment, the server 10 can send information about the character encoding method while sending content data. Therefore, even if the character encoding method of the content data being sent changes midway, for example, the server 10 can notify the client 20 of the changed character encoding method information via SIT, allowing the client 20 to use the content data without garbling the character content.

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

Below, we will explain an example of the operation of the system related to this embodiment.

The server 10 has established a communication path with the client 20 and has been requested to send content. Furthermore, the server 10 and client 20 according to this embodiment are DTCP2 compatible, and the client 20 recognizes that the server 10 will send content data in a format compliant with DTCP2 at the time the communication path is established.

Figure 11 is a flowchart 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 for server/client communication (step S110). Once the communication path is established, the server 10 and client 20 communicate via the transceiver units 110 and 21.

When the server 10 receives a request to send content data to the client 20, the control unit 17 causes the broadcast signal receiving unit 11 or the storage unit 13 to output the encoded content data to the analysis unit 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), a content protection standard.

Figure 12A is a diagram showing an example of protection management information transmitted by the server in this embodiment, illustrating the structure of a CMI packet. A CMI packet consists of a Header and a Body. The Header and Body are each represented as 8-bit data lines, with the Header indicating information about the CMI packet being sent, and the Body indicating the CMI, i.e., protection management information, as the CMI Field.

Figure 12B shows an example of a field of protection management information transmitted by the server in this embodiment, and shows an example of the configuration of the Body portion of Figure 12A, i.e., the CMI Field. This shows an example in which two CMI Descriptors, X and Y, are placed in the CMI Field.

Figure 12C is a diagram showing an example of a descriptor written in the protection management information field transmitted by the server in this embodiment, and shows the contents of the CMI Descriptor in Figure 12B.

In this embodiment, an example is shown in which the CMI Descriptor in Figure 12C is placed in field 12B1 in Figure 12B. Field 12B1 is placed in field 12A1 in Figure 12A. In addition, for example, Char_encode_type is defined as an identifier indicating character encoding information and placed in field 12C1 in Figure 12C.

The value set for the encoding method and identifier Char_encode_type is, 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 generation unit 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 using a method defined in DTCP2 to generate a PCP (Protected Content Packet), and outputs this to the transmission/reception unit 110 as a protected content stream together with the CMI packet generated in step S113 (step S115). The CMI packet is not encrypted. The transmission/reception unit 110 transmits the protected content stream to the client 20 as a content stream signal (step S116). The server 10 ends the process if there is no more encoded content data to transmit from the broadcast signal reception unit 11 or the storage unit 13 (NO in step S111).

Figure 13 is a flowchart showing an example of a client's processing operation according to this embodiment.

The client 20 establishes a communication path with the server 10 for server/client communication (step S130). Once the communication path is established, the server 10 and client 20 communicate via the transceiver units 110 and 21.

When the transceiver 21 of the client 20 receives the content stream signal, it processes the content stream signal to obtain the protected content stream, outputs the CMI packet to the analyzer 25, and outputs the PCP to the content stream processor 23 (YES in step S131, step S132). The analyzer 25 detects the Char_encode_type setting value set by the server 10 in step S113 from the CMI packet and outputs the detected setting value to the controller 22. Meanwhile, the content stream processor 23 performs a process to remove content protection from the PCP and obtains the content stream (step S134). The controller 22 checks whether the client 20 supports the character encoding method corresponding to the input Char_encode_type setting value (step S135). When the control unit 22 confirms that the client 20 supports the character encoding method corresponding to the setting value of Char_encode_type, it causes the content stream processing unit 23 to process the content stream using the character encoding method corresponding to the setting value of Char_encode_type (YES in step S135). The content stream processing unit 23 decodes the encoded content data extracted from the content stream to obtain the content data. In this embodiment, the encoded character data is decoded using the character encoding method specified by the control unit 22 to obtain the character data (step S136). The obtained content data, including the character data, is output to the display output unit 24, which then outputs the video, audio, character data, etc. in a format that the user can view (step S137). The client 20 ends the processing when it no longer receives the content stream signal (NO in step S131).

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

In this way, in this embodiment, by notifying the client 20 of the character encoding method of the encoded character data sent by the server 10 in a CMI packet, the client 20 can use the content data without garbling the character content. According to this embodiment, the server 10 can also send character content to the client 20 without converting the character encoding method.

In particular, CMI packets are sent every time there is a change in the content written within the CMI packet, so it is possible to quickly detect the character encoding method even for content data where the character encoding method changes fairly frequently.

At least one of the embodiments described above can provide a content transmission device and transmission method that allows text content to be used without garbled characters.

It goes without saying that the first, second, third, and fourth embodiments may be implemented in any combination. Furthermore, the user may be able to set or switch between enabling and disabling the functions of any embodiment, i.e., be able to switch between combinations of embodiments.

The main points of the above-described system can also be described as follows: (A1) A 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 (three preceding waves) using a second character encoding method;
An analysis means for determining the character encoding method used in the video content received by the first broadcast receiving means or the second broadcast receiving means;
Character encoding used in the video content based on the determination result of the analysis means is the first character encoding, the second character encoding, or the first character encoding, the character encoding other than the second character encoding, character data conversion means for converting the third character encoding;
A content transmitting device comprising: a transmitting means conforming to the DLNA (registered trademark) standard for transmitting a video content signal including the video content whose character encoding method has been converted by the character data converting means. (A1-1)
The video content transmitting device according to (A1), wherein the video content received by the first broadcast receiving means or the second broadcast receiving means is directly input to the analyzing unit. (A1-2)
The content transmitting device according to (A1) includes a storage means for storing the video content received by the first broadcast receiving means or the second broadcast receiving means, and the analysis means receives the video content stored in the storage means as an input. (A2) A 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 (three preceding waves) using a second character encoding method;
An analysis means for determining the character encoding method used in the video content received by the first broadcast receiving means or the second broadcast receiving means;
An accompanying information adding means for adding information indicating the character encoding method used in the video content as content management information to the video content based on the determination result of the analysis means;
and a transmission means conforming to the DLNA (registered trademark) standard that transmits the video content to which the content management information has been added by the associated information adding means. (A2-1) The video content transmission device according to (A2), in which the video content received by the first broadcast receiving means or the second broadcast receiving means is directly input to the analysis means. (A2-2)
The content transmission device according to (A2), further comprising a storage means for storing video content received by the first broadcast receiving means or the second broadcast receiving means, and the analysis means receives as input the video content stored in the storage means. (A2-2-1)
When storing the video content received by the first broadcast receiving means or the second broadcast receiving means in the storage means, the character encoding method used in the received video content is converted to a character encoding method other than the character encoding method used and then stored, (A2-2) content transmission device (A2-2-2)
(A2-2) or (A-2-2), the content transmission device described in (A2-2) or (A-2-2), which combines the video content received by the first broadcast receiving means and the video content received by the second broadcast receiving means to form a single video content, and stores the combined video content in the storage means. (A3) The video content transmission device described in (A2), (A2-1), (A2-2), (A2-2-1), (A2-2-2), characterized in that the content management information assigned by the associated information assigning means is placed in a DLNA (registered trademark) media format profile transmitted by the transmission means. (A4) The video content transmission device described in (A2), (A2-1), (A2-2), (A2-2-1), (A2-2-2), characterized in that the content management information assigned by the associated information assigning means is placed in an SIT compliant with the MPEG-2 TS standard that is included in the video content signal transmitted by the transmission means. (A5) The video content transmission device described in (A2), (A2-1), (A2-2), (A2-2-1), and (A2-2-2) is characterized in that the video content transmission device is equipped with a content protection means compliant with the DTCP2 standard, and the content management information added by the associated information adding means is placed in a CMI packet generated by the content protection means.

While several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are within the scope and spirit of the invention, and are also included in the inventions and their equivalents as set forth in the claims. Furthermore, the scope of the present invention also includes cases in which each component in the claims is expressed separately, as a combination of multiple components, or as a combination of these. Furthermore, multiple embodiments may be combined, and examples composed of such combinations are also within the scope of the invention.

In addition, to clarify the explanation, the drawings may show the width, thickness, shape, etc. of each part more schematically than in the actual embodiment. In block diagrams, data and signals may be exchanged between unconnected blocks, or even between connected blocks in directions not indicated by arrows. The processes shown in flowcharts may be realized by hardware (e.g., IC chips), software (e.g., programs), or a combination of hardware and software. The device of the present invention is also applied when the claims are expressed as control logic, a program containing instructions for a computer to execute, or a computer-readable recording medium containing the instructions. Furthermore, the names and terminology used are not intended to be limiting; other expressions that have substantially the same content and intent are also included in the present invention.

(Additional Note) The above-described embodiment includes the following aspects.
[1] An encoded content data input/output means for inputting 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, and outputting second encoded content data obtained by encoding the content data and second content accompanying information accompanying the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
The character encoding information extracted by the analysis means and the information of the second character encoding that can be decoded by an external device, based on the character encoding for the character data of the second encoded content data converted character data conversion means for outputting third encoded content data;
a transmitting unit configured to transmit either the second encoded content data or the third encoded content data to the external device.
[2] The character encoding method of the first encoded content data is either the UTF-8 method or the 8-bit encoding method;
The character encoding method of the second encoded content data is either a UTF-8 method or an 8-bit encoding method, or a character encoding method other than a UTF-8 method or an 8-bit encoding method;
The content transmission device according to [1], wherein the character encoding method of the third encoded content data is either UTF8 or 8-bit encoding, or a character encoding method other than UTF8 or 8-bit encoding.
[3] A content transmission device described in either [1] or [2], wherein the encoded content data input/output means inputs the first encoded content data and the first content associated information obtained by processing a broadcast signal transmitted using an MPEG2 transport stream method, and outputs the first encoded content data and the first content associated information as the second encoded content data and the second content associated information.
[4] The encoded content data input/output means inputs the first encoded content data and the first content associated information obtained by processing a broadcast signal broadcast using the MMT system, and outputs the first encoded content data and the first content associated information as the second encoded content data and the second content associated information. [1] or [2] A content transmission device described in either one of [1] or [2].
[5] The encoded content data input/output means of the content transmitting device described in [1] stores the first encoded content data and the first content associated information transmitted by the broadcast signal, and outputs the stored first encoded content data and the first content associated information as the second encoded content data and the second content associated information.
[6] The encoded content data input/output means stores at least a portion of the input first encoded content data as second encoded content data converted into a second character encoding method different from the first character encoding method used in the first encoded content data, and outputs the second encoded content data. [1] A content transmission device as described in.
[7] The content transmission device described in [6], wherein the stored second encoded content data is encoded content data that combines encoded content data transmitted by a broadcast signal using the MPEG2 transport stream method and encoded content data transmitted by a broadcast signal using the MMT method.
[8] A method for encoding content data including at least character data transmitted by a broadcast signal, and first content-accompanying information associated with the first encoded content data are input, and second encoded content data obtained by encoding the content data and second content-accompanying information associated with the second encoded content data are output;
Analyze the second content associated information and extract the information of the character encoding used in the second encoded content data;
Based on the extracted character encoding information and the information of the second character encoding that can be decoded by the external device, convert the character encoding for the character data of the second encoded content data and output the third encoded content data;
A content transmission method for transmitting either the second encoded content data or the third encoded content data to the external device.
[9] An encoded content data input/output means for inputting 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, and outputting second encoded content data obtained by encoding the content data and second content accompanying information accompanying the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
Based on the information of the character encoding extracted by the analysis means, character data conversion means for converting the character encoding for the character data of the second encoded content data and outputting third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
The encoded content data input/output means inputs the first encoded content data and the first content associated information obtained by processing a broadcast signal transmitted by an MPEG2 transport stream system, and outputs the first encoded content data and the first content associated information as the second encoded content data and the second content associated information.
[10] An encoded content data input/output means for inputting 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, and outputting second encoded content data obtained by encoding the content data and second content accompanying information accompanying the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
Based on the information of the character encoding extracted by the analysis means, character data conversion means for converting the character encoding for the character data of the second encoded content data and outputting third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
The encoded content data input/output means inputs the first encoded content data and the first content associated information obtained by processing a broadcast signal broadcast using the MMT system, and outputs the first encoded content data and the first content associated information as the second encoded content data and the second content associated information.
[11] An encoded content data input/output means for inputting 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, and outputting second encoded content data obtained by encoding the content data and second content accompanying information accompanying the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
Based on the information of the character encoding extracted by the analysis means, character data conversion means for converting the character encoding for the character data of the second encoded content data and outputting third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
The encoded content data input/output means is a content transmitting device that accumulates the first encoded content data and the first content associated information transmitted by the broadcast signal, and outputs the accumulated first encoded content data and the first content associated information as the second encoded content data and the second content associated information.
[12] An encoded content data input/output means for inputting 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, and outputting second encoded content data obtained by encoding the content data and second content accompanying information accompanying the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
Based on the information of the character encoding extracted by the analysis means, character data conversion means for converting the character encoding for the character data of the second encoded content data and outputting third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
The encoded content data input/output means stores at least a portion of the input first encoded content data as second encoded content data converted into a second character encoding method different from the first character encoding method used in the first encoded content data, and outputs the second encoded content data.

10: Server, 11: Broadcast signal receiving unit, 12: Display output unit, 13: Storage unit, 14: Analysis unit, 15: Associated information generating unit, 16: Character data conversion unit, 17: Control unit, 18: Content stream generating unit, 19: Content protection unit, 20: Client, 21: Transmitter/receiver unit, 22: Control unit, 23: Content stream processing unit, 24: Display output unit, 25: Analysis unit, 110: Transmitter/receiver unit.

Claims (2)

an encoded content data input/output means for inputting 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, and outputting second encoded content data obtained by encoding the content data and second content accompanying information accompanying the second encoded content data;
An analysis means for analyzing the second content associated information and extracting information on the character encoding used in the second encoded content data;
Based on the information of the character encoding extracted by the analysis means, a character data conversion means for converting the first character encoding for the character data of the second encoded content data to output third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
Further, the external client communicates with the external client, obtains information on the second character encoding method that the client can support, and compares it with the information on the first character encoding method for the character data in the third encoded content data. If the two match, the encoded content data containing the encoded character data by the first character encoding method is input to the content stream generation unit. If the two do not match, the character data in the third encoded content data is input to the character data conversion means.
Content transmission device. an encoded content data input/output means inputting first encoded content data obtained by encoding content data including at least character data transmitted by a broadcast signal and first content associated information associated with the first encoded content data, and outputting second encoded content data obtained by encoding the content data and second content associated information associated with the second encoded content data;
The analysis means analyzes the second content associated information and extracts the information of the character encoding used in the second encoded content data;
Character data conversion means, based on the information of the character encoding extracted by the analysis means, converts the first character encoding for the character data of the second encoded content data and outputs the third encoded content data;
a transmitting means for transmitting either the second encoded content data or the third encoded content data to an external device,
Further, the external client is communicated with, and the information of the second character encoding method that the client can support is obtained, and the information of the first character encoding method for the character data in the third encoded content data is compared with the information of the first character encoding method, and if the two match, the encoded content data containing the encoded character data by the first character encoding method is input to the content stream generation unit, and if the two do not match, the character data in the third encoded content data is input to the character data conversion means,
How content is sent.