JP4925266B2 - Content download method and content download device - Google Patents

Description

The present invention relates to a content download method and content download equipment to download content to the terminal. Here, the content is broadcast by at least a broadcasting station or a distribution device.

  In recent years, the transition from analog terrestrial television broadcasting to terrestrial digital television broadcasting has been promoted, and terrestrial analog television broadcasting will be canceled around 2011 after terrestrial digital television broadcasting has spread throughout the country. It has become. Then, the VHF (Very High Frequency) band is released from terrestrial analog television broadcasting. Terrestrial digital audio broadcasting is a next-generation broadcasting that uses the VHF band, and has already been experimentally performed.

The standard of digital terrestrial audio broadcasting is defined as ISDB-TSB (Integrated Services Digital Broadcasting-Terrestrial for Sound Broadcasting) (ARIB STD-B29) in the Association of Radio Industries and Businesses (for example, (Refer nonpatent literature 1.).
“Transmission Standard for Digital Terrestrial Audio Broadcasting ARIB STD-B29 Version 2.1” Publisher: Japan Radio Industry Association, Month of Publication: July 2003

  In terrestrial digital audio broadcasting, it is possible to broadcast not only audio but also various contents (still images, moving images, data, etc.). Therefore, it can be assumed that the receiving device for digital terrestrial audio broadcasting has a function of downloading, storing, and reproducing content broadcast from a broadcasting station, and the user enjoys such content. .

  For example, if a basic broadcast is broadcast in the A layer of digital terrestrial audio broadcasting, a link to content broadcast in the B layer is included in the broadcast, and the link is selected by the user in the receiving apparatus It can be assumed that the receiving device downloads the content, stores it, and then plays it back and forth.

  In terrestrial digital audio broadcasting, content is broadcast by a DSM-CC data carousel (Digital Storage Media-Command and Control Data Carousel) transmission system defined in ISO / IEC 13818-6. Even if a part of the blocks fails to be downloaded once, the failure can be compensated by downloading the blocks repeatedly broadcast after the failure.

  However, since the number of repetitions of one module is limited, after all the repetitions are completed, the receiving device can no longer download the block from the broadcast station, and the block can be downloaded from the broadcast station. Fail completely. For example, such a situation occurs when the download of a certain module is started when the end of the module is being repeated, and the download of the same block fails subsequently. In such a case, the download of the content that requires all the blocks fails as a whole.

  In addition, when the receiving apparatus fails to download a part of the block of the content once and downloads the block repeatedly broadcast after the failure, the receiving apparatus compensates for the failure. At least until the next block is broadcast. Accordingly, since the repetition cycle per module is long, the download end time may be considerably delayed.

Therefore, the present invention provides a content download method and content download device that can acquire a part of the content that has been broadcast from the broadcasting station even if the part of the content has failed to be downloaded. The purpose is to provide a device.

In addition, the present invention provides a content download method and a content download method that enable early acquisition of a part of the content even when the part of the content broadcast from the broadcasting station has failed to be downloaded. an object of the present invention is to provide a download equipment.

According to the present invention, primary download means for downloading content broadcast from a broadcasting station or a distribution device, detection means for detecting a portion of the content that has failed to be downloaded by the primary download means, Secondary download means for downloading a portion of the content that failed to be downloaded by the primary download means from a server via a communication line, and the detection means and the secondary download means include: The primary download means operates before the entire content is completed, the primary download means operates in accordance with a carousel transmission system, and the detection means performs repetitive transmission of a module including a certain block. That the block was downloaded successfully Before long, when the repetitive transmission of the module is completed, it is detected that the download of the block by the primary download means has failed, and the secondary download means includes the primary download means. content download system according to claim download on the block that failed is detected downloaded from the server by is provided.

  According to the present invention, a primary download step of downloading content broadcast from a broadcasting station or a distribution device, a detection step of detecting a portion of the content that has failed to be downloaded by the primary download step, A second download step of downloading a portion of the content that failed to be downloaded in the first download step from a server via a communication line, and the detection step and the second download step include: The primary download step is performed before the entire content is completed, and the primary download step operates according to a carousel transmission method. In the detection step, in the repeated transmission of a module including a certain block, That The second download step detects that the download of the block has failed in the first download step with the end of repeated transmission of the module before the lock download has been successful. Then, a content download method is provided, wherein the block detected to have failed to download in the first download step is downloaded from the server.

According to the present invention, primary download means for downloading content broadcast from a broadcasting station or a distribution device, detection means for detecting a portion of the content that has failed to be downloaded by the primary download means , Secondary download means for downloading a portion of the content that failed to be downloaded by the primary download means from a server via a communication line, so that a part of the content broadcast from the broadcast station Even if the download fails, that part of the content can be acquired.

Further, according to the present invention, the detection means and the secondary download means are configured to perform the operation before the operation of the primary download means is completed for the entire content. Even if the download of a part of the content that has been made fails, that part of the content can be acquired at an early stage.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  First, the configuration of the content download system according to the present embodiment will be described.

  Referring to FIG. 1, the content download system according to the present embodiment includes a broadcasting station 101, a plurality of terminals 102-1, 102-2,... 102-N, a first server 103, and a second server 105. .

  The broadcasting station 101 performs terrestrial digital audio broadcasting. The terrestrial digital audio broadcast from the broadcast station 101 includes content. The terminal 102 is, for example, a mobile phone, in addition to the functions of a normal mobile phone (call function, mail function, address book function, browsing function, etc.), a function of receiving terrestrial digital audio broadcast from the broadcast station 101, It has a function of performing bidirectional communication with the first server 103 and the second server 105 via the mobile network 104. The terminal 102 also has a function of downloading content included in the terrestrial digital audio broadcast and additionally downloading a portion of the content that has failed to download from the second server 105. The first server 103 has a function of authenticating the terminal 102, charging the terminal 102, and sending a decryption key to the terminal 102. The second server 105 transmits, to the terminal 102, a portion requested from the terminal 102 in the content included in the terrestrial digital audio broadcast from the broadcasting station 101.

  Accordingly, the broadcasting station 101 functions as a primary content distribution device, and the second server 105 functions as a secondary content distribution device.

  The mobile network 104 includes a base station, a base station controller, an interface with the first server 103, an interface with the second server 105, an SGSN (Serving GPRS Support Node), and a GGSN (Gateway GPRS). Support Node (Gateway GPRS Support Node), WPG (WAP Gateway), MSC (Mobile Service Switching Center), SMS-C (Short Message Service Center) -Service Center), PPG (Push Proxy Gateway), etc. are included.

  Further, data having the same content as the digital terrestrial audio broadcast transmitted from the broadcasting station 101 is stored in a distribution server connected to a network such as the Internet, and the terminal 102 has a function of downloading the data (so-called “ The network distribution of the television broadcast or the radio broadcast ") can perform the same operation as the terminal 102 receiving the terrestrial digital audio broadcast broadcast from the broadcast station 101. The following description of the broadcasting station and related parts also applies when the broadcasting station is replaced with a distribution server.

  The terrestrial digital audio broadcast is, for example, compliant with ISDB-TSB (ARIB STD-B29) as described above. In terrestrial digital audio broadcasting, as shown in FIG. 2, one of a plurality of segments (for example, 8, 14 (depending on the usable frequency bandwidth)) included in one VHF channel or UHF channel. The segment (three in the example of FIG. 2) is used for one terrestrial digital audio broadcasting channel. The transmission rate per segment is about 330 kbps, for example, and the frequency bandwidth per segment is about 432 kHz, for example. As a modulation method, for example, OFDM (Orthogonal Frequency Division Multiplexing) is used.

  A plurality of segments included in one digital terrestrial audio broadcasting channel are classified into an A layer and a B layer. In the A layer, BML (Broadcast Markup Language) data, moving image data, still image data, audio data, caption data, and the like are broadcast. In the B layer, contents (for example, still image data, moving image data, audio data, document data, etc.) are broadcast. However, in general, the usage form of the A hierarchy and the B hierarchy is free and may be used in other forms. A receiver that has selected a certain terrestrial digital audio broadcasting channel can receive all data of the A layer and the B layer. In BML included in a certain elementary stream in layer A, if a link to content included in a certain elementary stream in layer B is described, the content is output by the user selecting the link. become able to.

  BML is an application language of XML, and adopts CSS (Cascading Style Sheets), DOM (Document Object Model), and ECMA Script (script) standards. In the BML data, character data to be displayed, scripts, and the like are described. In addition, according to the description of the BML data, still image data, caption data, and the like are arranged on the screen.

  BML data, still image data, content, and the like are broadcast by a DSM-CC data carousel (Digital Storage Media-Command and Control Data Carousel) transmission system defined in ISO / IEC 13818-6. As shown in FIGS. 3 and 4, according to this transmission method, data to be transmitted (“transmission data” shown in FIG. 3) is divided into a plurality of modules, and each module is divided into a plurality of blocks. Is done. And all the modules which comprise transmission data are transmitted repeatedly. In each repetition, all the modules constituting the transmission data are sequentially transmitted only once. In the transmission of one module, a plurality of DDBs belonging to the module are sequentially transmitted only once. Further, when the capacity of transmission data is smaller than the capacity of one module, only one module can be obtained from the transmission data. Transmission data here is one content, a part of one content, or a plurality of contents. In order for transmission data to correspond to one content and to be composed of a plurality of modules, a function for dividing one content into a plurality of modules on the transmission side and restoring the content on the reception side is necessary. It becomes. When the transmission data is a plurality of contents, a multipart format is used.

  Each block in the data carousel system is assigned to the payload of each section (similar to PES) in the transport stream referred to in the MPEG (Moving Picture Experts Group) standard. In each section, a cyclic redundancy code (CRC (Cyclic Redundancy Check)) is added to the payload, and error detection can be performed on the receiving side.

  For example, only blocks satisfying a predetermined condition for normal download such as no error is detected from the section corresponding to the block, version information is normal, etc. are written to the buffer according to the module ID and block number on the receiving side. Like that. In addition, if a block that does not satisfy a predetermined condition for normal download is associated with a flag, a module ID, and a block number indicating that block, the block of that module could not be downloaded correctly. Can be detected.

  Referring to FIG. 5, the broadcasting station 101 includes an A layer transmission processing unit 200-1, a B layer transmission processing unit 200-2, a transmission path encoding unit 207, and an RF (Radio Frequency) unit 208.

  The A layer transmission processing unit 200-1 generates a transport stream based on the data to be transmitted in the A layer, and outputs this to the transmission path encoding unit 207.

  The B layer transmission processing unit 200-2 generates a transport stream based on the data to be transmitted in the B layer, and outputs this to the transmission path encoding unit 207.

  The transmission path encoding unit 207 performs transport stream remultiplexing, error correction encoding, interleaving, modulation, OFDM frame configuration, IFFT, etc. for the transport stream input from the A layer and the transport stream input from the B layer. And outputs the result as a transmission signal.

  The RF unit 208 transmits a transmission signal as a broadcast radio wave.

  Referring to FIG. 6, layer A transmission processing section 200-1 includes an encoder group 201, a PES conversion section 202, a carousel transmission processing section 204, a sectioning section 205, and a transport stream (TS) multiplexing section 206.

  The encoder group 201 includes a plurality of encoders. Each encoder corresponds to the type of each content, and is, for example, a moving image encoder, a still image encoder, an audio encoder, a caption encoder, or a document data encoder.

  The PES unit 202 divides each elementary stream (ES: Elementary Stream) input from the encoder group 201 into a plurality of packets, and outputs the result as a PES (Packetized Elementary Stream). A PID (Packet ID) indicating a base elementary stream is attached to the PES.

  The carousel transmission processing unit 204 performs a carousel transmission process on content input from the encoder group 201 or content input from outside without going through the encoder group 201. Specifically, the content is divided into a plurality of modules, each module is divided into blocks, and a plurality of DDBs (Download Data Blocks) are output for each module.

  The section unit 205 performs sectioning processing on the DII and DDB input from the carousel transmission processing unit 204, the PSI / SI (Program Specific Information / Specific Information) and the event message input from the outside. Specifically, a header (including a table ID) and CRC (Cyclic Redundancy Check) are added to the input payload portion, and the resulting section is output.

  The TS multiplexing unit 206 generates a transport stream by multiplexing the PES input from the PES converting unit 202 and the section input from the sectioning unit 205, and outputs the transport stream.

  The BML data included in the A layer is input to the TS multiplexing unit 206 via the carousel transmission processing unit 204 and the sectioning unit 205. The moving image data and audio data included in the A layer are input to the TS multiplexing unit 206 via the encoder group 201 and the PES conversion unit 202. Still image data included in the A layer is input to the TS multiplexing unit 206 via the encoder group 201, the carousel transmission processing unit 204, and the sectioning unit 205. Subtitle data included in the A layer is input to the TS multiplexing unit 206 via the encoder group 201 and the sectioning unit 205.

  Referring to FIG. 7, the layer B transmission processing unit 200-2 includes an encoder group 201, a PES conversion unit 202, an encryption unit 203, a carousel transmission processing unit 204, a sectioning unit 205, and a TS multiplexing unit 206. 6 is different from the A-layer transmission processing unit 200-1 shown in FIG. 6 in that an encryption unit 203 is added.

  The encoder group 201, the PES conversion unit 202, the section unit 205, and the TS multiplexing unit 206 are the same as those of the A layer transmission processing unit 200-1, and thus description thereof is omitted.

  The encryption unit 203 encrypts content input from the encoder group 201 or content input from the outside without going through the encoder group 201. Encryption is performed using an encryption key corresponding to the content title. Here, the title is, for example, in the case of music, a combination of a song title and a performer (including a singer) (may include the place of performance, date and time, etc.), and in the case of a movie. For example, the name (which may include the language of audio or subtitles). However, it is not essential to have a one-to-one correspondence between the content and the encryption key. One encryption key is associated with one authentication, and a plurality of contents or a part of one content is assigned to one encryption key. You may make it respond | correspond.

  The carousel transmission processing unit 204 performs a carousel transmission process on content input from the encoder group 201, content input from the encryption unit 203, or content input from the outside without the encoder group 201 and the encryption unit 203. .

  The content included in the B layer is transmitted through the encoder group 201, the encryption unit 203, the carousel transmission processing unit 204, and the sectioning unit 205, or without passing through the encoder group 201. The data is input to the TS multiplexing unit 206 via the processing unit 204 and the sectioning unit 205.

  Referring to FIG. 8, each terminal 102 includes a tuner unit 221, a transmission path decoding unit 222, a TS demultiplexing unit 223, a PES reception processing unit 224, a section reception processing unit 225, a carousel reception processing unit 226, a decoder group 227, BML browser 228, content download unit 229, content storage unit 230, mobile network antenna 231, mobile network modulation / demodulation unit 232, decryption key acquisition unit 233, decryption key storage unit 234, decryption unit 235, display unit 236 Speaker 237, key group 238, and user interface control unit 239.

  The tuner unit 221 receives the broadcast radio wave transmitted from the RF unit 208 of the broadcast station 101 corresponding to the designated terrestrial digital audio broadcast channel, and restores the transmission signal.

  The transmission path decoding unit 222 performs processing reverse to the processing of the transmission path encoding unit 207 to restore the A layer transport stream and the B layer transport stream.

  The TS demultiplexing unit 223 demultiplexes the PES and the section from the designated transport stream of the A layer transport stream and the B layer transport stream input from the tuner 222.

  The PES reception processing unit 224 restores the elementary stream for each PID based on the PES input from the TS demultiplexing unit 223.

  The section reception processing unit 225 restores the data before sectioning for each table ID based on the section input from the TS demultiplexing unit 223. The section reception processing unit 225 performs error detection based on the CRC for each section, and sets a flag indicating that data cannot be restored for the section in which the error is detected.

  The carousel reception processing unit 226 basically collects a plurality of blocks input from the section reception processing unit 225 (a plurality of blocks downloaded from the broadcast station 101), thereby restoring each module and collecting a plurality of modules. Thus, the transmission data is restored. In addition, the carousel reception processing unit 226 additionally inputs a block that has failed to be downloaded from the broadcast station 101 from the mobile network modulation / demodulation unit 232 (downloads from the second server 105), and also uses that block. The associated module is restored, and finally the transmission data is restored.

  Referring to FIG. 9, the carousel reception processing unit 226 includes a section payload receiving unit 226-1, a DII buffer 226-2, a DDB buffer 226-3, a block error flag buffer 226-4, and a module restoring unit 226. 5, a module buffer 226-6, a module error flag buffer 226-7, a content restoration unit 226-8, a block buffer 226-9, and a control unit 226-10.

  The section payload receiving unit 226-1 receives the payload of each section from the section reception processing unit 225, and stores the payload in the DII buffer 226-2 or the DDB buffer 226-3 depending on the type. Also, based on the CRC check results for the payload, version information, DII inspection results, DDB inspection results, DII and DDB cross-reference results, etc., errors are determined for each block and downloaded to which block of which module A block error flag indicating whether an error has occurred is written to the block error flag buffer 226-4. The error flag of the block is set before the block is first received, and the error flag of the block is reset when the block is normally received for the first time. By doing this, the error flag of the block that has been successfully received even once is reset, and the error flag of the block that has not been normally received is still set.

  The DII buffer 226-2 stores the DII for each repetition of carousel transmission.

  The DDB buffer 226-3 stores a plurality of DDBs for each module.

  The module restoration unit 226-5 basically collects a plurality of blocks based on the contents read from the DII buffer 226-2, the DDB buffer 226-3, and the block error flag buffer 226-4. Thus, each module is restored, and each module is written in the module buffer 226-6. In addition, if an error is included in at least one block that constitutes a module, the module cannot be restored, so that a module error flag indicating that the module cannot be restored is set as a module error flag. Write to the flag buffer 226-7.

  The module buffer 226-6 stores one or more modules constituting the content.

  The content restoration unit 226-8 restores the content based on the contents read from the module buffer 226-6 and the module error flag buffer 226-7, and outputs the content to the content download unit 229. To do. Further, when an error is included in at least one module constituting a certain content, the content cannot be restored. Therefore, a content error flag indicating that the content cannot be restored is displayed in the content download unit. 229 may be output.

  The block buffer 226-9 stores the block input from the mobile network modem 232.

  The control unit 226-10 controls the overall operation of the carousel reception processing unit 226. In particular, the control unit 226-10 refers to the output signal of the section payload receiving unit 226-1, the block error flag buffer 226-4, or the like that the downloading of a certain block from the broadcasting station 101 has failed. If it is detected, an instruction (including information for identifying the block, information for identifying the second server 105, etc.) is issued to the mobile network modulation / demodulation unit 232. 2 Download from the server 105. The blocks so downloaded are stored in the block buffer 226-9. When the module restoration unit 226-5 restores the module, the module stored in the block buffer 226-9 is also used.

  Returning to FIG. 8, the decoder group 227 includes a plurality of decoders. Each decoder corresponds to the type of each content, and is, for example, a moving picture decoder, a still picture decoder, an audio decoder, a caption decoder, or a document data decoder.

  The BML browser 228 displays the screen to be displayed on the display unit 236 and the audio to be output from the speaker 237 according to the description in the BML file input from the carousel reception processing unit 226 and the user operation input from the user interface control unit 239. The screen and audio obtained as a result are output to the display unit 236 and the speaker 237, respectively. In particular, the BML browser 228 downloads a certain content of the B level based on the description in the BML file input from the carousel reception processing unit 226 and the user operation input from the user interface control unit 239. If it is detected that an operation has been performed, the content download unit 229 is activated, and the content download unit 229 is instructed to download the content. For this activation, for example, a function for activating the content download unit 229 described in the BML file is executed. In addition, as content location information for designating content, for example, the URI of the content is used. As this URI, for example, the following one defined in ARIB STD-B24 is used.

arib-dc: // <original_network_id>. <transport_stream_id>
. <service_id>[; content_id] [. event_id] /
<component_tag> / <module_name>
Here, original_networ_id is an ID unique to each master, for example, an ID of FM Tokyo (registered trademark). transport_stream_id is an ID unique to each transport, for example, an ID of a B-layer transport stream of a certain three-segment terrestrial digital audio broadcast. service_id is for identifying the inside of one organization channel in the terrestrial digital audio broadcasting channel. The component_tag specifies an elementary stream (or a stream composed of a series of sections). module_name designates a specific content among a plurality of contents flowing in time series in the elementary stream.

The content download unit 229 downloads content instructed from the BML browser 228. An example of the operation will be described. Based on the content position information, the designation of the terrestrial digital audio broadcasting channel including the content is output to the tuner unit 221 and the designation of the transport stream including the content is TS. The data is output to the demultiplexing unit 223. Of the data transmitted from the tuner unit 221 through the transmission path decoding unit 222, the TS demultiplexing unit 223, the section reception processing unit 225, and the carousel reception processing unit 226,
<service_id><component_tag> / <module_name>
The content corresponding to the content position information, which is data corresponding to, is input and the content is written in the content storage unit 230. However, normally, since the terrestrial digital audio broadcasting channel including the content is the same as the current channel, it is not necessary to specify the channel. When the data that is made into a single piece of data by the carousel transmission processing unit 204 and the carousel reception processing unit 226 is a part of a certain content, the content download unit 229 collects a plurality of these to obtain one content. Process to restore.

  In addition, when the data that is grouped by the carousel transmission processing unit 204 and the carousel reception processing unit 226 is multipart content, it may be stored in the content storage unit 230 as it is, The contents may be separately stored in the content storage unit 230.

  The content storage unit 230 stores content from the content download unit 229. The content storage unit 230 is, for example, a non-volatile memory (for example, EEPROM, flash memory) built in the mobile phone, a non-volatile memory inserted into the mobile phone, or the like.

  The mobile network antenna 231 transmits and receives mobile network radio waves to and from a base station (not shown) of the mobile network 104.

  The mobile network modulation / demodulation unit 232 performs modulation / demodulation according to, for example, a W-CDMA (Wideband-Code Division Multiple Access) method, a PDC (Personal Digital Cellular) method, a GSM (Global System for Mobile Communications) method, and the like.

  Referring to FIG. 10, the content stored in the content storage unit 230 includes an encrypted part (encrypted part) and information for obtaining a decryption key for decrypting the encrypted part (encryption). Decryption key acquisition information). However, the content may not include the decryption key acquisition information, and the decryption key acquisition information may be included in the related part of the content (for example, a packet carrying the content). The decryption key acquisition information includes, for example, identification information of a server that sends a decryption key and identification information of a content title. The content is divided into a plurality of parts, and the encrypted part of each part is encrypted with a different encryption key for each part, so that each part includes the encrypted part and the corresponding decryption key acquisition information. Also good. In addition, the encrypted part of the content included in the multipart format can be decrypted with a different decryption key for each content, and the decryption key acquisition information for each content is stored in the entire multipart content. It may be included in places or dispersedly. Also, the encrypted part of all the contents included in the multipart format can be decrypted with the same decryption key so that one piece of information for obtaining the decryption key is included in the entire contents of the multipart format. Also good.

  The decryption key acquisition unit 233 is activated by the content download unit 229, and the decryption key acquisition information contained in the content stored in the content storage unit 230 by the content download unit 229 or its related part is stored in the content or The decryption key is downloaded from the first server 103 using the decryption key acquisition information obtained from the relevant part. However, immediately after the content is downloaded, the decryption key acquisition unit 233 is not activated by the content download unit 229, but when the user first tries to view the content, the user interface control unit that has detected it is detected. The decryption key acquisition unit 233 may be activated by the H.239.

  The decryption key storage unit 234 stores the decryption key downloaded by the decryption key acquisition unit 233. The decryption key storage unit 234 is, for example, a nonvolatile memory built in the mobile phone, a nonvolatile memory inserted into the mobile phone, or the like. In addition, by limiting the decryption key storage unit 234 to the nonvolatile memory built in the mobile phone, it is possible to eliminate the portability of the decryption key and to protect the copyright of the content.

  The decryption unit 235 reads the content designated by the user interface control unit 239 from the content storage unit 230, reads the decryption key corresponding to the content from the decryption key storage unit 234, and reads the encrypted part of the content. Decryption is performed using the decryption key, and the content having no encrypted portion is output to the decoder group 228.

  A decoder corresponding to the content input from the decryption unit 235 is selected from the decoder group 228, and the decoder decodes the content. The decoded content is output to the display unit 236, the speaker 237, or both.

  In addition, when the content is image data specified by BML data that should be incorporated into a screen according to BML data or audio data specified by BML data that should be synchronized with a screen according to BML data In such a case, such content is read from the content storage unit 230 in accordance with an instruction from the BML browser 228 and input to the BML browser 228 via the decryption unit 235 and the decoder group 228. good.

  In addition, the content input to the encryption unit 203 without passing through the encoder group 201 in the broadcasting station 101 is input to the display unit 236, the speaker 237, or the BML browser 228 from the decryption unit 235 without passing through the decoder group 228. You may make it.

  The display unit 236 displays a screen according to the image data input from the BML browser 228 and the image data input from the decoder group 228. Further, the display unit 236 displays a screen for the user interface in accordance with a signal from the user interface control unit 239.

  The speaker 237 outputs sound according to the sound data input from the BML browser 228 and the sound data input from the decoder group 228. The speaker 237 outputs a sound for the user interface in accordance with a signal from the user interface control unit 239.

  The key group 238 includes numeric keys, symbol keys, direction keys, function keys, and the like.

  The user interface control unit 239 uses the display unit 236, the speaker 237, and the key group 239 to control the interface with the user. In addition, the instruction content from the user is output to the BML browser 228, the decryption unit 235, the decoder group 227, and the like.

  When this is a mobile phone, the terminal 102 includes parts (for example, a microphone, a voice codec, a mail function part, an address book part, and a browser part) other than the parts shown in FIG. Is omitted. Further, the terminal 102 only needs to have a portion as shown in FIG. 8, and may be, for example, a PHS terminal, a personal computer, a PDA (Personal Digital Assistant), or the like. Therefore, what connects the terminal 102 to the first server 103 and the second server 105 is not limited to the mobile network 104, and generally the terminal 102 performs two-way communication with the first server 103 and the second server 105. Any communication line may be used as long as it is possible, for example, a mobile network, a fixed telephone network, and the Internet may be included.

  Further, of the parts shown in FIG. 8 (for example, the BML browser 228 and the content / downloading part 229) other than the parts (for example, the content storage unit 230 and the decryption key storage unit 234) that can only be realized by hardware. ) May be realized by hardware, software, or a combination of hardware and software.

  Referring to FIG. 11, the first server 103 includes a communication unit 251, an authentication unit 252, a billing unit 253, a decryption key storage unit 254, and a decryption key reading unit 255.

  The communication unit 251 is for communicating with the terminal 102 via the mobile network 104.

  The authenticating unit 252 authenticates the terminal 102 based on the device identification information and the personal identification number of the terminal 102 sent from the terminal 102. If authentication is successful and charging is successful, a permission signal is output to the decryption key reading unit 255.

  The charging unit 253 performs processing for charging associated with transmission of the decryption key for the authenticated terminal 102.

  When it is determined by referring to a user database (not shown) or the like whether or not the user of the terminal 102 satisfies the predetermined condition instead of charging the authenticated terminal 102 In addition, the authentication unit 252 may output the permission signal to the decryption key reading unit 255 without charging.

  The decryption key storage unit 254 stores a decryption key corresponding to the title of each content that can be downloaded by terrestrial digital audio broadcasting.

  When receiving the permission signal from the authentication unit 252, the decryption key reading unit 255 is identified by the decryption key acquisition information received from the terminal 102 among the decryption keys stored in the decryption key storage unit 254. The decryption key to be read is read from the decryption key storage unit 254 and sent to the terminal 102 via the communication unit 251.

  Referring to FIG. 12, the second server 105 includes a communication unit 261, a content storage unit 262, and a block reading unit 263.

  The communication unit 261 is for communicating with the terminal 102 via the mobile network 104.

  The content storage unit 262 holds the same content as the content broadcast from the broadcast station 101. Although there are usually many contents broadcast from the broadcasting station 101, it is not always necessary to have many contents. In addition, each content stored in the content storage unit 262 can be read for each block. The block here may be a DDB, or may be a block including data necessary for restoring a module.

  The block reading unit 263 reads the block requested from the terminal 102 (for example, specified by the content title identification information, module identification information, and block identification information) from the content storage unit 262 and outputs the block to the communication unit 261. .

  Similarly to the first server 103, the second server 105 may include an authentication unit or an authentication unit and a billing unit, and the block may be transmitted only to terminals that have been authenticated or authenticated and billed.

  The block reading unit 263 reads from the content storage unit 262 the block identified by the title identification information, the module identification information, and the block identification information of the content received from the terminal 102 among the content stored in the content storage unit 254, The data is transmitted to the terminal 102 via the communication unit 261.

  Next, the basic operation of the content download system according to the present embodiment will be described.

  The content can be included in the A layer or the B layer. Therefore, the content can be downloaded by receiving only the A layer. However, in the following, description will be given taking a typical case where content is included in the B layer and link information to the content is included in the A layer.

  Referring to FIG. 13, first, when a terrestrial digital audio broadcast channel is selected by the user, the terminal 102 receives the broadcast content of the A layer of the channel, displays it on the display unit 236, and outputs it from the speaker 237. (Step S301). The screen displayed by the display unit 236 includes an object (for example, a button, a character string, an image, and the like) for starting the download of B-layer content according to the BML data. This object is associated with a function for starting the content download unit 229 and content position information in accordance with the BML data. In addition, information (content recognition information) for allowing the user to recognize the contents of the B hierarchy is displayed near the object according to the BML data. Further, during the period in which the screen including this object is displayed, the content recognition information corresponding to the content of the B layer and having the audio form is output from the speaker 237 according to the BML data. good. The content recognition information is, for example, a content title, a still image or a simple moving image representing a performer or a performer, a still image or a simple moving image of a moving image content, a description, a music intro or a touch.

  During this time, the user interface control unit 239 continuously monitors the signal from the key group 238 to determine whether or not an operation has been performed on the object for starting the content download of the B layer (for example, the button is pressed). Whether or not) (step S302).

  If an operation for starting the download of the B-layer content is detected (YES in step S302), the content download unit 229 downloads the content identified by the content position information and stores it in the content storage unit 230. Store (step S303).

  Next, the decryption key acquisition unit 233 downloads the decryption key for decrypting the encrypted part of the content downloaded in step S303 and stores it in the decryption key storage unit 234 (step S304).

  Finally, the decoder corresponding to the content in the decoder group 228 reproduces (decodes) the content stored in the content storage unit 230 in step S303 (step S305). At this time, the decryption unit 235 decrypts the encrypted part of the content.

  Next, details of steps S303 and S304 will be described.

  Referring to FIG. 14, if the BML browser 228 inputs an event indicating that an operation has been performed on an object for starting the download of B-layer content from the user interface control unit 239, the event and the BML data The content position information is acquired from the DOM tree data based on the description of the DOM tree data obtained from (step S303-1).

  Next, the BML browser 228 activates the content download unit 229 and passes the content position information to the content download unit 229 (step S303-2).

  The activated content download unit 229 downloads the content specified by the content position information (step S303-3) and stores it in the content storage unit 230 (step S303-4).

  Next, the content download unit 229 activates the decryption key acquisition unit 233 (step S304-1), and the activated decryption key acquisition unit 233 is stored in the content storage unit 230 in step S303-4. The decryption key acquisition information is acquired from the content (step S304-2), the decryption key specified by the decryption key acquisition information is downloaded (step S304-3), and stored in the decryption key storage unit 234. (Step S304-4).

  Next, details of step S305 will be described.

  Referring to FIG. 15, the user interface control unit 239 activates the decoder corresponding to the content in the decryption unit 235 and the decoder group 228 when it is detected that the content is requested to be played back by the user (step S21). S305-1). Next, the activated decryption unit 235 uses the decryption key stored in the decryption key storage unit 234 in step S304-4 as the encrypted part of the content stored in the content storage unit 230 in step S303-4. Decryption is performed (step S305-2), and the activated decoder reproduces (decodes) the content having no encrypted portion (step S305-3).

  Next, six operation examples when a download error occurs in the content download system according to the present embodiment will be described.

[First operation example]
As shown in FIG. 16, in the first operation example, after the entire content has been downloaded (step S401) regardless of whether or not a download error has occurred, the block in which the download error has occurred 2 Download from the server 105 (step S403). Here, a block in which a download error has occurred is a block that has never been successfully downloaded. When there are a plurality of blocks in which a download error has occurred, when downloading from the second server 105, a plurality of blocks may be downloaded one by one, or a plurality of blocks (for example, A plurality of blocks for each module, or a plurality of blocks for the entire content) may be downloaded together. In the example of FIG. 16, the block in which the download error has occurred is block B2-2. As indicated by B2-2 (1), B2-2 (2), and B2-2 (3), the block B2-2 has been transmitted three times, but has not been successfully downloaded all three times. The control unit 226-10 detects an error in the block B2-2 with reference to the block error flag buffer 226-4. Referring to the module error flag buffer 226-7, an error in the module M2 is detected, and then only a portion related to the module M2 in the block error flag buffer 226-4 is referred to, so that the block B2 -2 error may be detected. Before referring to the module error flag buffer 226-7, the error flag for the entire content is checked, and the module error flag buffer 226-7 is set only if the error flag is set. You may make it refer. Subsequently, the block B2-2 is downloaded from the second server 105 and stored in the block buffer 226-9. Subsequently, the module restoration unit 226-5 restores the module M2, and the content restoration unit 226-9 restores the entire content.

  If it is detected before the download from the second server 105 of a certain block that the radio wave conditions etc. are bad and cannot be communicated with the second server 105 via the mobile network 104, the download is stopped. , You may postpone it. The same applies to second to sixth operation examples to be described later.

  If download of a block from the second server 105 fails, it may be repeated until it succeeds. Even in the repetition, if it is detected that the radio wave condition is bad and the communication with the second server 105 cannot be performed via the mobile network 104, the repetition may be stopped or postponed. The same applies to second to sixth operation examples to be described later.

  In the case of the first operation example, when broadcasting of a certain content ends, many terminals may request the second server 105 to transmit a block, and the communication line may be congested. In order to avoid this, for example, the terminal 102 may generate a delay time using a random number or the like, and may request the second server 105 to transmit a block after the delay time has elapsed.

[Second operation example]
As shown in FIG. 17, in the second operation example, for each module, when the carousel reception process of the module is completed (step S411), a download error occurs in a plurality of blocks constituting the module. The downloaded block is downloaded from the second server 105 (step S413). When the content is composed of only one module, the timing coincides with the first operation example. Here, a block in which a download error has occurred is a block that has never been successfully downloaded. When there are a plurality of blocks in which a download error has occurred, when downloading from the second server 105, a plurality of blocks may be downloaded one by one, or a plurality of blocks may be combined. You can download it. In the example of FIG. 17, this is block B2-2 where a download error has occurred. As indicated by B2-2 (1), B2-2 (2), and B2-2 (3), the block B2-2 has been transmitted three times, but has not been successfully downloaded all three times. The carousel reception process continues as usual, and the process proceeds to the third carousel reception process of the module M3. In parallel with this, the control unit 226-10 refers to the block error flag buffer 226-4 to detect an error in the block B2-2. Subsequently, the block B2-2 is downloaded from the second server 105 and stored in the block buffer 226-9. Subsequently, the module restoration unit 226-5 restores the module M2. When the carousel reception process is completed for all the modules, and when necessary, when the download from the second server 105 of the block in which the download error has occurred in the carousel transmission is completed, the content restoration unit 226-9 Restore the entire content.

  In the case of the second operation example, when carousel transmission of a certain module with a certain content is completed, a large number of terminals may request the second server 105 to transmit a block, and the communication line may be congested. In order to avoid this, for example, the terminal 102 may generate a delay time using a random number or the like, and may request the second server 105 to transmit a block after the delay time has elapsed.

  It can be detected as follows that the content is composed of a plurality of modules and the download by the carousel transmission of the block included in the module other than the last module has failed.

  If identification information indicating whether or not the current repetition is the last repetition is put in an area that can be set independently by the broadcaster in DII, whether the currently received module is the module in the last repetition You can know whether or not. If it is detected that the module is the last module and the reception of the DDB block of the next module is started, it means that the repeated transmission of the current module has been completed. It is possible to know whether or not an error is included in the transmission of each block of the current module. The reception of the DDB block of the next module is detected based on the module size described in DII and the number of DDB blocks per module obtained from the DDB block defined in the standard. it can.

In addition, if identification information indicating how many times the remaining number of repetitions is included in an area that can be uniquely set by the broadcaster in DII, whether or not the currently received module is the module in the last repetition is determined. Can know. If it is detected that the module is the last module and the reception of the DDB block of the next module is started, it means that the repeated transmission of the current module has been completed. It is possible to know whether or not an error is included in the transmission of each block of the current module.
According to the second operation example, when the content is composed of a plurality of modules and downloading by the carousel transmission of the block included in the module that is not the last module fails, an effect superior to the first operation example occurs. That is, before the download of the last module by the carousel reception process is completed, there is a high possibility that the block from the second server 105 that has failed to be downloaded by the carousel reception process will be completed. Therefore, even if there is a download failure due to the block carousel reception process, it is more likely that the download end time of the entire content will not change compared to when there is no failure.

[Third operation example]
As shown in FIG. 18, in the third operation example, if a download error has occurred even once in a block of a module (step S421), the block is downloaded from the second server 105 (step S423). Carousel reception processing continues as usual. Here, the block in which the download error has occurred is the block B2-2 (1) in the example of FIG. The control unit 226-10 detects an error in the block B2-2 (1) with reference to the block error flag buffer 226-4. Subsequently, the block B2-2 is downloaded from the second server 105 and stored as the block B2-2 (S) in the block buffer 226-9. The module restoration unit 226-5 restores the module M2 if each of the blocks constituting the module M2 is stored in at least one of the DDB buffer 226-3 and the block buffer 226-9. To do.

  For example, the block B2-1 (1) and the block B2-3 (1) have been successfully downloaded, and the block B2- is sent from the second server 105 earlier than when the block 2-2 (2) is broadcast. 2 can be downloaded as the block B2-2 (S), the block M2-1 (1), the block B2-2 (S), and the block B2-3 (1) are prepared and then the module M2 based on these. To restore. However, even in such a case, after the block B2-1 (1), the block B2-2 (2), and the block B2-3 (1) are prepared, the module M2 is restored based on these. Also good.

  Also, for example, block B2-1 (1) and block B2-3 (1) have been successfully downloaded, and block B2-2 is downloaded from second server 105 as block B2-2 (S). If the block 2-2 (2) is normally downloaded early, the block B2-1 (1), the block B2-2 (2), and the block B2-3 (1) are prepared and then the module is based on them. Restore M2. However, even in such a case, after the block B2-1 (1), the block B2-2 (S), and the block B2-3 (1) are prepared, the module M2 is restored based on these. Also good.

  According to the third operation example, as in the second operation example, even if there is a download failure due to the block carousel reception process, the download end time of the entire content does not change compared to the case where there is no failure. The possibility increases.

  Further, according to the third operation example, it is possible to re-download blocks as early as possible. Further, when downloading from the second server 105 fails, it can be dealt with by continuous carousel reception processing.

[Fourth operation example]
As shown in FIG. 19, in the fourth operation example, if a download error has occurred even once in a block of a module (step S431), the block is downloaded from the second server 105 (step S433). The carousel reception process continues normally, but the carousel reception process of the block in which the download error has occurred may be terminated as long as the download of other blocks is not affected. Here, the block in which the download error has occurred is the block B2-2 (1) in the example of FIG. The control unit 226-10 detects an error in the block B2-2 (1) with reference to the block error flag buffer 226-4. Subsequently, the block B2-2 is downloaded from the second server 105 and stored as the block B2-2 (S) in the block buffer 226-9. The module restoration unit 226-5 stores, in the DDB buffer 226-3, blocks that have not failed to receive carousel among all the blocks that constitute the module M2, and blocks that have been downloaded from the second server 105 due to failure to receive carousel. Is stored in the block buffer 226-9, the module M2 is restored.

  For example, when the block B2-1 (1) and the block B2-3 (1) have been successfully downloaded and the block B2-2 has been downloaded from the second server 105 as the block B2-2 (S), After the block B2-1 (1), the block B2-2 (S), and the block B2-3 (1) are prepared, the module M2 is restored based on these.

  According to the fourth operation example, as with the second operation example, even if there is a download failure due to the block carousel reception process, the download end time of the entire content may not be changed compared to when there is no failure. Increases nature.

  Further, according to the fourth operation example, it is possible to re-download blocks at an early stage.

[Fifth operation example]
As shown in FIG. 20, in the fifth operation example, if a download error has occurred even once in a block of a module (step S441), the time at which the download of that block that is again transmitted by carousel is completed ( End time 1) is estimated (step S443), and when the block is downloaded from the second server 105, the download end time (end time 2) is estimated (step S445), and the end time 1 and end time 2 are calculated. In comparison (step S447), if it is determined that the end time 2 is earlier than the end time 1 (YES in step S447), the block is downloaded from the second server 105 (step S449). Carousel reception processing continues as usual. Here, the block in which the download error has occurred is the block B2-2 (1) in the example of FIG. The control unit 226-10 detects an error in the block B2-2 (1) with reference to the block error flag buffer 226-4 (step S441). Subsequently, steps S443, S445, and S447 are performed. If YES in S447, the block B2-2 is downloaded from the second server 105 and stored in the block buffer 226-9 as the block B2-2 (S). The

  FIG. 21 shows an example in which steps S443, S445, and S447 are performed immediately after a certain block is unsuccessfully downloaded (not synchronized with the end time of one cycle of the module). Time T0 is the time at which steps S443, S445, and S447 are performed. Assuming that the estimated value of the time required for downloading from the second server 105 is ΔT, the estimated value of the end time of downloading from the second server 105 is time T2 (= T0 + ΔT). The estimated value of the download end time by the carousel reception process is indicated by time T1. (A) shows the case where the download of the block B1-1 (1) has failed, (b) shows the case where the download of the block B1-2 (1) has failed, and (c) shows the block B1- 3 (1) shows a case where the download has failed. In any case, T1> T2. However, if the estimated value ΔT of the time required for downloading from the second server 105 is longer than the carousel transmission period (period of sending B1-1 (n) to B3-3 (n)), in any case , T1 <T2.

  Accordingly, FIG. 21 shows that when steps S443, S445, and S447 are performed immediately after a certain block is unsuccessfully downloaded, the time corresponding to one cycle of carousel transmission (= T1-T0) regardless of the number of the block that failed to download. ) And the estimated value ΔT of the time required for downloading from the second server 105 indicate that the context of the end time 1 and the end time 2 is determined.

  The time for one cycle (the cycle for sending B1-1 (n) to B3-3 (n)) is the number of modules per transmission data, the number of blocks per module, the amount of data per block ( The number of bytes), the transmission rate of the layer including the transmission data (for example, layer B), the ratio of the data amount of the elementary stream containing the transmission data in the transport stream, etc. I can do it. On the other hand, the estimated value ΔT of the time required for downloading from the second server 105 can be estimated based on the data amount per block, the current transmission rate of the communication line, and the like. Both can also be estimated based on past measurements. If the radio wave conditions are poor and communication with the second server 105 via the mobile network 104 is not possible, time T1 <time T2.

  FIG. 22 shows an example in which downloading of a certain block fails, and thereafter steps S443, S445, and S447 are performed in synchronization with the end time of one cycle of the module including that block in carousel transmission. Time T0 is the time at which steps S443, S445, and S447 are performed. Assuming that the estimated value of the time required for downloading from the second server 105 is ΔT, the estimated value of the end time of downloading from the second server 105 is time T2 (= T0 + ΔT). The estimated value of the download end time by the carousel reception process is indicated by time T1. (A) shows a case where downloading of the block B1-1 (1) has failed, and in this case, T1 <T2. (B) shows a case where the download of the block B1-2 (1) has failed, and in this case, T1 = T2. (C) shows a case where the download of the block B1-3 (1) has failed. In this case, T1> T2. However, if the estimated value ΔT of the time required for downloading from the second server 105 is different, the context of T1 and T2 changes.

  Therefore, FIG. 22 shows that when downloading a block fails and steps S443, S445, and S447 are performed in synchronization with the end time of one cycle of the module including the block in carousel transmission, one cycle of carousel is performed. Depending on not only the estimated value of time (= T1-T0) and the estimated value ΔT of the time required for download from the second server 105, but also the end time 1 and end time 2 Indicates that the context is determined.

  In addition, as shown in FIG. 22, when downloading of a certain block fails and thereafter steps S443, S445 and S447 are performed in synchronization with the end time of one cycle of the module including the block in carousel transmission. The downloading of other blocks in the same module may also have failed. When there are a plurality of blocks in which a download error has occurred in one module in this way, when downloading from the second server 105, the plurality of blocks are downloaded one by one. Alternatively, a plurality of blocks may be downloaded together.

  Returning to FIG. 20, if YES in S447, the normal carousel reception process and the download from the second server 105 are performed in parallel, and the module restoration unit 226-5 is configured to configure all the modules M2. If each of the blocks is stored in at least one of the DDB buffer 226-3 and the block buffer 226-9, the module M2 is restored.

  If NO in S447, only normal carousel reception processing will be continued, and the module restoration unit 226-5 will have the module restoration unit 226-5 if all the blocks constituting the module M2 have been stored in the DDB buffer 226-3. The module M2 is restored.

  According to the fifth operation example, as with the second operation example, even if there is a download failure due to the carousel reception process of the block, the download end time of the entire content may not be changed compared to the case where there is no failure. Increases nature.

  Further, according to the fifth operation example, as in the third operation example, it becomes possible to re-download blocks as early as possible. Further, when downloading from the second server 105 fails, it can be dealt with by continuous carousel reception processing.

  Furthermore, according to the fifth operation example, since the download request times are distributed, it is possible to reduce the possibility that the second server 105 is overloaded and the communication line is congested as compared with the third operation example. On the other hand, if the end time 1 is earlier than the end time 2 against the estimate, there is no need to wait until the end time 2.

[Sixth operation example]
As shown in FIG. 23, in the sixth operation example, if a download error has occurred even once in a block of a module (step S461), the time at which the download of the block that is again transmitted through the carousel ends ( End time 1) is estimated (step S463), and when the block is downloaded from the second server 105, the download end time (end time 2) is estimated (step S465), and end time 1 and end time 2 are calculated. When the comparison is made (step S467) and it is determined that the end time 2 is earlier than the end time 1 (YES in step S467), the block is downloaded from the second server 105 (step S469). The carousel reception process continues normally, but the carousel reception process of the block in which the download error has occurred may be terminated as long as the download of other blocks is not affected. Here, the block in which the download error has occurred is block B2-2 (1) in the example of FIG. The control unit 226-10 detects an error in the block B2-2 (1) with reference to the block error flag buffer 226-4. Subsequently, steps S443, S445, and S447 are performed. If YES in S447, the block B2-2 is downloaded from the second server 105 and stored in the block buffer 226-9 as the block B2-2 (S). The

  If YES in S467, the module restoration unit 226-5 stores in the DDB buffer 226-3 the blocks that have not failed to receive carousel among all the blocks constituting the module M2, and failed to receive carousel. If the block downloaded from the second server 105 is stored in the block buffer 226-9, the module M2 is restored.

  If NO in S467, only the normal carousel reception process will be continued, and the module restoration unit 226-5 will determine that all the blocks constituting the module M2 have been stored in the DDB buffer 226-3. The module M2 is restored.

  The matters described with reference to FIGS. 21 and 22 are the same as those in the case of the fifth operation example, and thus redundant description is omitted.

  According to the sixth operation example, as in the second operation example, even if there is a download failure due to the carousel transmission of the block, the download end time of the entire content may not be changed compared to the case where there is no failure. Becomes higher.

  Further, according to the sixth operation example, since the download request times are distributed, it is possible to reduce the possibility that the second server 105 is overloaded and the communication line is congested as compared with the fourth operation example.

[Seventh operation example]
The re-downloading according to the third operation example, the fourth operation example, the fifth operation example, or the sixth operation example is always possible, and the block that cannot be downloaded normally still remains. When the carousel transmission of the module including the end is completed and the carousel transmission of the next module is started, re-downloading is performed according to the second operation example, and there is still a block that cannot be normally downloaded once. If the content carousel transmission has been completed while remaining, re-downloading may be performed according to the first operation example. In this case, when downloading of a certain block from the second server 105 fails, the operation of repeating it until it succeeds may or may not be performed. In addition, when the download from the second server 105 of a certain block fails, the operation of repeating it until it succeeds is partially (for example, when re-downloading according to the first operation example) Only).

  In the above embodiment, terrestrial digital audio broadcasting has been described as an example. However, the present invention may be applied to digital broadcasting such as terrestrial digital television broadcasting and satellite digital television broadcasting.

It is a block diagram which shows the structure of the content download system by embodiment of this invention. It is a figure which shows the frequency band utilized by terrestrial digital audio broadcasting. It is a figure which shows the data division | segmentation method etc. in a carousel transmission system. It is a timing diagram which shows a carousel transmission system. It is a block diagram which shows the structure of the broadcasting station shown in FIG. It is a block diagram which shows the structure of the A hierarchy transmission process part shown in FIG. It is a block diagram which shows the structure of the B hierarchy transmission process part shown in FIG. It is a block diagram which shows the structure of the terminal shown in FIG. It is a block diagram which shows the structure of the carousel reception process part shown in FIG. It is a figure which shows the structure of the content in embodiment of this invention. It is a block diagram which shows the structure of the 1st server shown in FIG. It is a block diagram which shows the structure of the 2nd server shown in FIG. 3 is a flowchart illustrating a content download method performed by the content download system according to the embodiment of the present invention. It is a flowchart which shows the detail of step S303 and S304 shown in FIG. It is a flowchart which shows the detail of step S305 shown in FIG. It is a timing diagram and a flowchart for explaining the first operation example. It is a timing chart and a flowchart for explaining the 2nd example of operation. It is a timing diagram and a flowchart for explaining a third operation example. It is a timing diagram and a flowchart for explaining a fourth operation example. It is a timing chart and a flowchart for explaining the 5th example of operation. It is a figure which shows the example of the end time 1 and the end time 2 when performing an asynchronous operation | movement with respect to repetition of carousel transmission in a 5th operation example and a 6th operation example. It is a figure which shows the example of the end time 1 and the end time 2 at the time of synchronizing operation | movement with respect to repetition of carousel transmission in a 5th operation example and a 6th operation example. It is a timing diagram and a flowchart for explaining a sixth operation example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Broadcast station 102-1, 102-2, ..., 102-N terminal 103 1st server 104 Mobile network 105 2nd server 105 2nd server 200-1 A hierarchy transmission process part 200-2 B hierarchy transmission process part DESCRIPTION OF SYMBOLS 201 Encoder group 202 PES conversion part 203 Encryption part 204 Carousel transmission process part 205 Sectioning part 206 TS multiplexing part 207 Transmission path encoding part 208 RF part 221 Tuner part 222 Transmission path decoding part 223 TS demultiplexing part 224 PES Reception processing unit 225 Section reception processing unit 226 Carousel reception processing unit 226-1 Section payload payload receiving unit 226-2 DII buffer 226-3 DDB buffer 226-4 Block error flag buffer 226-5 Module restoration unit 226 6 Module buff A 226-7 Module error flag buffer 226-8 Content restoration unit 226-9 Block buffer 226-10 Control unit 227 Decoder group 228 BML browser 229 Content download unit 230 Content storage unit 231 Mobile network antenna 232 Mobile Modulation / demodulation unit for network 233 Decryption key acquisition unit 234 Decryption key storage unit 235 Decryption unit 236 Display unit 237 Speaker 238 Key group 239 User interface control unit 251 Communication unit 252 Authentication unit 253 Accounting unit 254 Decryption key storage unit 255 Decryption key reading unit

Claims (4)

A first download means for downloading content broadcast from a broadcasting station or a distribution device;
Detecting means for detecting a portion of the content that has failed to be downloaded by the primary download means;
Secondary download means for downloading a portion of the content that failed to be downloaded by the primary download means from a server via a communication line;
Equipped with a,
The detection means and the secondary download means operate before the operation of the primary download means ends for the entire content,
The first download means operates according to a carousel transmission method,
In the repetitive transmission of a module including a certain block, the detection means detects that the first download of the block has been completed when the repetitive transmission of the module has been completed before the block has been downloaded successfully. Detect that the download failed by means,
The secondary download device, content download and wherein the download on the block that failed to download is detected by the first-order download device from the server. The content download device according to claim 1,
The content download apparatus, wherein the communication line includes at least one of a mobile network, a fixed telephone network, and the Internet. A first download step of downloading content broadcast from a broadcasting station or a distribution device;
A detection step of detecting a portion of the content that has failed to be downloaded by the primary download step;
A second download step of downloading a portion of the content that failed to be downloaded in the first download step from a server via a communication line;
Have
The detection step and the secondary download step are performed before the primary download step is completed for the entire content,
The first download step operates according to a carousel transmission method,
In the detection step, in the repeated transmission of a module including a certain block, the first download of the block is completed when the repeated transmission of the module is completed before the block has been downloaded successfully. Detect that the step download failed,
In the second download step, the block that is detected to have failed to download in the first download step is downloaded from the server. The content download method according to claim 3,
The content download method, wherein the communication line includes at least one of a mobile network, a fixed telephone network, and the Internet.

Images