JP2011135441A - Content distribution apparatus, receiving device, and broadcasting system with them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a system capable of downloading and receiving distributed content data in a short time. <P>SOLUTION: A content distribution apparatus distributes content data forward from the head and also distributes content data backward from the end. In a receiving device, the content data distributed forward and backward are received, respectively, and rearranged via a buffer, a storage section is provided for sequentially storing the content data rearranged, and the content data are read out of the storage section and reproduced. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a content distribution device that distributes multimedia content, a reception device that can receive content that is distributed (distributed wirelessly or wiredly) from the distribution device, and that can be played back via a display unit, and the like This is related to a broadcasting system that distributes and enables reception and reproduction by a receiving device.

  There is a system in which desired information is selected from a large number of provided information and is reproduced so that it can be viewed through a display medium or the like. For example, information desired by the user can be easily obtained from various information via the Internet.

  Also, in a broadcasting system that distributes information using wireless or wired information, various types of information (contents) are distributed from a broadcasting station (distribution unit) provided with a content distribution device. The content is selected using a tuner or a receiving device having a display unit, and is received and displayed and reproduced. For example, when various types of content such as video (including audio) and information such as text are distributed wirelessly, a content file is transmitted (distributed) on a carrier frequency determined by a broadcasting station. . The transmitted content file is received using a receiving device, which is a terminal device including a tuner and a display unit, converted into data that can be displayed on the display unit, and sound can be reproduced on the audio output unit, and can be viewed by the user. I am doing so.

  As described above, the broadcasting system wirelessly transmits, for example, video content on a predetermined carrier frequency from the broadcasting station side via the content distribution device. On the receiving side, the video content of the target carrier frequency is selectively received via the tuner, demodulated into data that can be reproduced and displayed, and the video content is reproduced and displayed for viewing.

  As receiving devices that can receive and view various multimedia contents to be distributed, mobile terminal devices represented by mobile phone terminals are widely used. This mobile terminal device can obtain not only a telephone but also various information via a network, and can transmit it to other mobile terminal devices.

  As the multimedia content transmission system, terrestrial digital broadcasting (one-segment broadcasting) for portable devices using the ISDB-T (Integrated Service Digital Broadcasting-Terrestrial) system has been started. Other broadcasting technologies for portable devices include a MediaFLO (forward link only) method for performing streaming distribution or download distribution of video content to a mobile phone terminal.

  By wirelessly transmitting content related to movies and various types of information using the one-segment method or the MediaFLO method described above, the content can be viewed on a mobile terminal device that is a receiving device to which a reception and playback function is added. The restrictions on where content can be viewed have been resolved. That is, the user can select and view the content desired by the receiving device (television or the like) installed at a predetermined position, and can carry it to an arbitrary place and view it at an arbitrary position. Therefore, it can be freely viewed at any place and in any time zone.

  Therefore, in Patent Document 1 (Japanese Patent Laid-Open No. 2008-306520), further customer satisfaction is achieved in a mobile phone terminal device (hereinafter referred to as a mobile phone) that receives and reproduces various contents using the above-described method. Inventions to improve have been proposed. That is, in cooperation with the data communication function of the mobile phone, a new viewing mode of the target content is created on the mobile phone, and the satisfaction of the user who owns the mobile phone is improved.

  On the other hand, analog broadcasting will end in 2011. A new utilization method using the frequency band is assumed and is being implemented. For example, a multimedia broadcasting service for mobile terminals is scheduled to start. As the multimedia broadcasting service, a broadcasting system such as the above-mentioned MediaFLO system or ISDB-Tmm (Integrated Service Digital Broadcasting Terrestrial Mobile Multi-Media Broadcasting) system is being studied by a service provider.

  In addition to the real-time broadcasting service that receives and plays back video data such as moving images including audio to be broadcast without storing it in the receiving device (mobile phone etc.) as a new broadcasting service among multimedia broadcasting services for mobile terminals, An implementation of a download broadcasting service in which video data including audio is once stored in a receiving terminal and then reproduced is assumed. This download broadcasting service corresponds to the file casting service in ISDB-Tmm and the clip cast in MediaFLO. These methods are as described in the report contents of November 2008 of the Information and Communication Council Information and Communication Technology Subcommittee established by the Ministry of Internal Affairs and Communications (Non-Patent Documents 1 and 2).

  The download broadcast service described above has an advantage that the quality of the content itself such as image quality can be flexibly changed instead of lacking immediacy compared to the real-time broadcast service. In addition, as described above, one-seg broadcasting is one of the leading multimedia broadcasting services for mobile terminals. However, since one-seg broadcasting has a transmission rate of about 400 bps, fixed subtitles are difficult to read. The image quality is insufficient compared with the conventional terrestrial TV broadcasting for terminals.

  On the other hand, according to the storage-type download broadcasting service, immediacy is unnecessary even if the transmission rate is low, so it takes time to increase the amount of data and provide high-quality content, that is, deliver it. be able to.

JP 2008-306520 A

"Outline of multimedia broadcasting system ISDB-Tmm for mobile devices" (URL: www.soumu.go.jp/joho_tsusin/policyreports/joho_tsusin/housou_system/pdf/081128_1_si16-3-1.pdf) “Outline of MediaFLO” (URL: www.soumu.go.jp/joho_tsusin/policyreports/joho_tsusin/housou_system/pdf/081128_1_si16-3-2.pdf)

  The above-described multimedia broadcasting service for portable terminals is also assumed to be supplementarily distributed using IP, but distribution (transmission) using radio broadcast waves is used as the center of the service as in the case of one-segment broadcasting. Therefore, it is necessary to install the mobile terminal device in an environment where the distributed content can be received satisfactorily. For example, when downloading and receiving content distributed while moving, if the environment is not received in the middle, part of the video content cannot be received normally, and the part is played back with the part missing. It also becomes.

  For this reason, movement to an unreceivable position is restricted while the target content is being received and sequentially accumulated. That is, the movement is restricted until the reception of the data of all the series of content files is completed during reception.

  In addition, when the target content is downloaded and viewed by the download broadcasting service, if the predetermined time is reserved, the target content can be stored in the order of reception without any problem. However, even if you forget the reservation and start the download of the target content after the start of the broadcast time, the initial video content data cannot be obtained, and a series of content files from the beginning to the end Cannot watch. For example, broadcasting starts at 10:00 PM, and even if a download service is received after the start, it is natural that all contents cannot be viewed. This is not limited to the download broadcast service, and the same applies to reception by a real-time service.

  The present invention aims to solve the above-mentioned problems.

  Therefore, an object of the present invention is to provide a content distribution apparatus, a receiving apparatus, and a broadcasting system that can shorten the time for receiving a download service.

  By achieving this object, it is possible to receive a download service in a short time that can maintain the reception environment. For example, when the time for distributing (transmitting) content file data (downloading time) is 1 hour, the download can be completed in a minimum of 30 minutes, and restrictions on movement can be suppressed.

  It is another object of the present invention to provide a distribution device, a receiving device, and a broadcasting system that can receive a download service for all series of content files even after the broadcast start time has elapsed.

  Furthermore, the present invention makes it possible to provide content that cannot be received by a real-time service.

  The present invention is a content distribution apparatus for distributing multimedia content, which divides the entire length of a series of content files into a plurality of pieces, maps them as packets in the forward and reverse directions, and forwards and reverses them. Each packet mapped in the direction is distributed.

  Therefore, for example, the content distribution apparatus divides a series of content files into a plurality of pieces, and assigns (numbering) identification numbers for identifying each divided divided data in the forward direction (in ascending order from the initial number). In this case, when the identification number is assigned in the forward direction, for example, the identification number “1” of the initial number is assigned to the first divided data of the series of content files, and the final divided data at the end of the sequential content file An identification number “N”, which is a number, is assigned. Distribution starts in order from the first divided data (identification number is “1”) mapped in this way, and distribution of terminal division data (identification number is “N”) is performed at the end of distribution.

  Simultaneously with this forward delivery, delivery in the reverse direction is performed. In this case, distribution starts in reverse order from the divided data at the end of the divided content file (final number identification number “N”), and finally the first divided data (identification number is “1”) is distributed. .

  According to such a content distribution apparatus, the content file data divided into a plurality of at least two channels are sequentially distributed for forward distribution and reverse distribution.

  The broadcast system includes the content distribution apparatus having the above-described configuration, and receives and downloads the content distributed from the distribution apparatus. For this purpose, a receiving apparatus is provided that includes means for receiving data of content files distributed in the reverse order simultaneously with receiving data of content files distributed in the forward direction.

  Therefore, the receiving device includes means for receiving data of a content file to be distributed, a processing unit that demodulates the received content file so that the received content file can be viewed via a display medium, and the divided data demodulated by the processing unit. Then, rearrangement is performed via the rearrangement processing unit, and this is sequentially stored in the storage unit. In this case, the rearrangement processing unit refers to the identification numbers “1” to “N” of the divided data mapped on the distribution device side, and stores them in the storage unit (accumulation unit), for example, in numerical order. Then, by storing the divided data having identification numbers “1” to “N” of the divided divided data, reception is completed, that is, download is completed.

  The receiving apparatus receives the divided data of “2”, “3”,... Sequentially from the identification number “1” of the first divided data distributed in the forward direction by the receiving means, and demodulates the divided data. Memorize temporarily. The receiving unit receives the divided data “N−1”, “N-2”,... Sequentially from the last identification number “N” distributed in the reverse direction. The receiving device demodulates the divided data and temporarily stores it. Then, the rearrangement processing unit refers to the identification numbers corresponding to the temporarily stored divided data, rearranges the data in the order of the numbers, and sequentially stores the data in the storage unit. ”To“ N ”are determined to be received as a series of content data, and the download process is terminated.

  As described above, in the receiving device, a series of all content files can be acquired in the middle of download delivery, and if a series of content files are received from the start of delivery (broadcast start), A series of content files can be received in at least half (1/2) of the time for distributing the data, and the download can be completed.

  Even if the download service cannot be received from the start of distribution, if a download service is received from the middle, it is possible to download the data of all series of content files. For example, if at least 30 minutes (half) of the download broadcast time zone (for example, 1 hour) has not elapsed, it is possible to view all the data of the content file that you want to view even if the distribution start time has passed. . This can be provided for the first time by the download broadcast service according to the present invention, which cannot be received by the real-time broadcast service.

  According to the content distribution apparatus according to the present invention described above, content files are distributed in the forward direction (in order from the beginning of the content file) and in the reverse direction (in reverse order from the end of the content file).

  Therefore, on the receiving device side, all the content files can be received in a short time by freely connecting the data distributed in the forward direction and the reverse direction, and can be freely viewed.

  Further, even after the content distribution start time, it is possible to receive a download service for all series of content files.

The figure for demonstrating the system configuration | structure concerning the delivery service of content data by the portable terminal device as a content delivery apparatus in this invention, and a receiver. The block diagram which shows an example of the receiver for receiving and reproducing the content data concerning this invention. The flowchart which shows an example of the control procedure concerning the reception start of the content data in the receiver of this invention. The flowchart which shows an example of the control procedure for the reception process of the content data in the receiver of this invention. The block diagram which shows the structure of the whole broadcasting system of this invention. The figure which shows an example of the mapping process procedure for dividing | segmenting and delivering the content data by this invention. The figure which shows the structure of a FDT instance packet. The figure which shows the structure of the LCT header in FIG. The figure which shows an example concerning the delivery process at the time of providing the identification number to the data packet which divided | segmented the content file.

  Embodiments of the present invention will be described below with reference to the drawings.

  The overall configuration of the broadcast system in the download distribution service of the present invention will be described with reference to FIGS. In FIG. 1, the broadcasting station side includes a content distribution apparatus 1 for providing a download distribution service according to the present invention. From this broadcasting station side, wireless distribution is performed through broadcasting radio waves. Therefore, the broadcast station side divides a series of content files into fixed lengths and divides them according to predetermined conditions in order to distribute packets. For example, a series of content files are divided, and the divided data is assigned as one packet, and a recognition number (ID) is assigned (numbered) in order from the top of the content file.

  In the example of FIG. 1, when a series of content files are divided into n parts, the identification number of the first divided data of the content file is set to “1”, and the divided data at the end of the content file is shown as “n”. ing. When each of the divided packets is wirelessly distributed from the broadcasting station (content distribution apparatus) 1 in order, from the channel 1 assigned to the distribution, the identification number “1” of the first packet of the content file is sequentially applied. In the forward direction of “2” and “3”, the final packet “n” that ends the distribution is distributed. On the other hand, from the channel 2, the packet to which the ID number at the end of the content file is assigned is delivered in reverse order.

  As described above, conventionally, when content files are simply distributed, the divided packets are distributed in a predetermined order (forward direction) through one allocated channel.

  On the other hand, in the present invention, a service is provided in which the divided packets are distributed in the forward direction from the beginning of the divided packets, and are distributed in the reverse direction from the terminal packets in the reverse order through the other channels.

  With the distribution of the content according to the present invention, the receiving device, which is the mobile phone A or B as the mobile receiving terminal in the example of FIG. 1, demodulates each piece of divided data of the content file included in the received packet, connects it, and After receiving the content file data, the content is reproduced and viewed via the display device and the audio output unit.

  In this respect, for example, the mobile phone B can be played back and viewed even on a device that can handle only one channel. The cellular phone B receives each divided packet distributed through one channel, for example, channel 1, demodulates the packet, and temporarily stores it in the storage unit. Thereafter, the user who owns the mobile phone B can view the content as needed through the display unit and the audio output unit via the reproduction control unit according to the user's instruction. Note that, when the mobile phone B receives channel 2, it receives from the end of the packet to be distributed, and therefore performs a rearrangement process according to the identification number of the received packet and finally receives the first packet. Thus, all the series of content files rearranged in the storage unit are stored.

  On the other hand, in the receiving apparatus in the broadcasting system that performs the content distribution service according to the present invention, the mobile phone A in FIG. This mobile phone A is one that incorporates, for example, a double tuner that can simultaneously receive a plurality of channels. Therefore, the cellular phone A sequentially receives the end packet “n” in order from the divided first packet “1” of the series of content files distributed in the channel 1 and sequentially from the end of the packet in the channel 2.

  Therefore, if the mobile phone A receives half of the divided packets, for example “n / 2”, through the channel 1 and receives the packet “n / 2 + 1” through the channel 2, all the content files in the series of content files are received. Data has been received. Therefore, in the related art, in the broadcasting system using the content distribution service according to the present invention, compared to the case where all the content files are received over the broadcasting time t, the broadcasting time t for distributing all the content file data is 1 / The reception can be completed (download completed) at time 2 (t / 2).

  Therefore, when the download service is received by the mobile phone A, the time in the reception environment can be greatly saved, and the saved time can be freely used, for example, moving to a place where the reception environment is bad, or other work. Can do.

  The mobile phone A has a function capable of receiving a plurality of channels as its configuration. The configuration will be described with reference to FIG.

  The mobile phone A which is a receiving device includes at least two tuners 12 and 13 for receiving a radio broadcast as receiving means. The receiving means includes an antenna portion that enables connection to a telephone network or the Internet. The telephone and internet connection parts are omitted.

  Data received through the tuners 12 and 13 is demodulated and stored in a buffer 14 that temporarily stores the data. This buffer 14 stores the identification number of each received packet. The data temporarily stored in the buffer 14 is rearranged by the rearrangement accumulation processing unit 15 in the order of the identification number of each packet, and is sequentially accumulated in the order of the packet numbers in the storage unit 16 which is a storage unit. Therefore, when a series of all divided data is received and stored in the storage unit 16 and all of the received series of content files are stored, the content data stored through the playback control unit 17 according to a user instruction is It is reproduced so that it can be viewed by the user via the display unit 18 and the audio output unit 19.

  In FIG. 2, although a control device that controls each unit is not shown, data processing is performed as described above via a control device that is not shown. Therefore, the control procedure by the control device will be described in detail with reference to the control flowcharts of FIGS.

  First, in FIG. 3, the user selects target content from among a plurality of contents to be distributed. Therefore, the reception channel is set. Depending on the set channel, the control device causes the tuners 12 and 13 to receive the target content file to be distributed. At this time, when the content file to be distributed is based on the distribution service according to the present invention, the data distributed via the two tuners is received.

  Each packet of received content file data includes a series of content size data, and the control device confirms this size data. For example, the total number (n) obtained by dividing a series of content files is included in the packet. By knowing the total number of packets, the total data size of the content file can be recognized. For example, since a series of content files are divided into fixed lengths, the total data length can be calculated from the total number of divisions (n) and the determined fixed-length data amount.

  Therefore, the data length of the content file to be distributed and received is acquired (step S1). It is determined whether or not all the acquired data lengths can be stored, that is, stored in the storage unit 16 (S2). Here, the storage unit 16 recognizes the capacity (remaining capacity) that can be stored via the control device, and compares whether the total data length (data amount) of the received content data can be stored.

  As a result of the comparison, if the capacity that can be stored in the storage unit 16 is smaller than the data amount of the content file to be received, the download is impossible, and the fact that it cannot be received is notified through the display unit 18 or the audio output unit 19 (S3). .

  As a result of the comparison, if the free space of the storage unit 16 is larger than the total data amount of the content files, the storage unit 16 reserves an area for storing a series of all content files. That is, an area for storing the total data of the received content is allocated to the storage unit 16 (S4).

  As described above, by assigning an area for storing the total content file data to be received to the storage unit 16, the control procedure shown in FIG. 4 is sequentially executed. First, the packet identification number stored in the buffer 14 is acquired (S5). As described above, the identification number of the packet from the beginning received on the channels 1 and 2 and the identification number of the packet at the end are confirmed each time a packet is received (S5).

  It is determined whether or not the identification number of the acquired packet matches that of the already received packet (S6). If it does not match the packet number already received, it is stored in the storage unit 16 corresponding to the identification number of the received packet. As described above, if there is a free capacity that can store all of the content files, the storage unit 16 is assigned an area in which the divided data of the content file can be stored. A storage (accumulation) portion corresponding to the identification number is defined as an address. Therefore, if it is not the identification number of the matching packet, the divided data included in the packet is sequentially stored (S7) in the storage portion corresponding to the number.

  Then, the control device determines whether or not content file data corresponding to all packet numbers has been stored in the storage unit 16 (S8). Therefore, it is determined whether or not all the packet identification numbers “1” to “n” have been received. If not all, the process returns to step S5 and the next packet identification number temporarily stored in the buffer 14 is returned. Get the data.

  Here, if the identification number of the acquired packet matches the identification number of the data already stored in the storage unit 16 in step S6, the process proceeds to step S8 without storing the data of the acquired packet identification number. Then, it is determined whether or not all the content file data has been received. If not, the process returns to step S5 to acquire the data of the identification number of the next packet.

  By processing the above control every time it receives a signal (packet) distributed, if the control device determines in step S8 that the reception of all packets has been completed, the reception is terminated and downloaded. Complete the process.

  At this time, if the content file to be distributed has been received from the beginning (broadcast start / distribution start), reception of all packets is completed at t / 2 hours with respect to the broadcast time (t) in FIG. Become. That is, when the packet number from the forward direction matches the packet number from the reverse direction, all content files have been received and stored.

  On the other hand, even if you forget to acquire the target content file from the start of broadcasting and start receiving from the middle, you cannot receive the packet distribution from the beginning of the content file. Since the packet is sequentially distributed from the identification number of the packet corresponding to the divided data, it can be received on the channel 2 side. Therefore, it is possible to receive and complement data that could not be received conventionally. Therefore, even if all the content files cannot be received conventionally, all the content files can be received and viewed even during the broadcast. However, in the middle of the broadcast, if a reception start is started within t / 2 hours of the broadcast time (t) from the start of the broadcast, it is possible to receive and watch all the series of distributed content files.

  In the above description, the tuners 12 and 13 shown in FIG. 2 are processing units each including means for demodulating the distributed data into data that can be reproduced for reception, and processing each data. The tuner 12 corresponds to a first processing unit that receives and processes data distributed in the forward direction, and the tuner 13 corresponds to a second processing unit that receives and processes data distributed in the reverse direction.

  The above is a description of the broadcasting system by the content distribution service in the new download according to the present invention.

  Next, a specific example of distribution processing of a content distribution service by a broadcasting system that provides a download service according to the present invention will be described. What is described below is an example for distribution, and is based on the ISDB-Tmm system of the broadcasting system for mobile terminals described above. It is not based on such a scheme, but various schemes that already provide distribution services can be adopted, and the present invention can be implemented by utilizing other schemes for distribution created in the future. Of course.

  In addition, the broadcast system for performing download distribution according to the present invention distributes any multimedia content to a large number of unspecified receiving terminals in a short time using radio broadcast radio waves in only one downlink direction. It is possible.

  FIG. 5 is a block diagram showing a schematic configuration of a broadcasting system that provides a download distribution service according to the present invention. As shown in the figure, the broadcast system for performing download distribution according to the present invention is a content distribution apparatus (broadcast transmission apparatus) 1 on the broadcast transmission side (broadcast station) described in FIG. For example, the mobile terminal device 10 is a receiving device for receiving and viewing content file data to be transmitted and a wireless transmission path 100 for transmitting broadcast data between the two. This is a general configuration. In the present invention, as described above, the distribution form in the content distribution apparatus 1 is characteristic, and the reception form on the receiving side is also characteristic.

(Configuration of content distribution device)
The content distribution apparatus 1 includes a content file storage unit 2 that stores data of a series of content files for distribution, a division that reads out the stored content file data, and divides the data into mapping data for distribution Processing unit 3, forward distribution processing unit 4 for distributing the divided data in the forward direction according to the present invention, backward distribution processing unit 5 for distributing the divided data from the reverse direction, both distribution processing units 4, 5, a multiplexer 6 for multiplexing the data output from 5, a transmission path encoder 7 for encoding the multiplexed signal, and a radio for wirelessly transmitting the data on the broadcast wave The broadcast wave transmission unit (distribution unit) 8 is provided. The elements of each component will be described below.

  The content file storage unit 2 stores a series of content file data for download distribution according to the present invention. A series of content file data stored in the content file storage unit 2 has an arbitrary file length. In order to distribute this data, as shown in FIG. 6, an arbitrary file is divided and a mapping process is performed by the division processing unit 3 in order to packetize the data. The present invention is not characterized in the mapping process itself by the division processing unit 3, and the mapping process shown in FIG. 6 is performed as in the prior art.

  The data mapped by the division processing unit 3 is sent to the forward distribution processing unit 4 and the reverse distribution processing unit 5, and distribution processing of the mapped data is performed. In particular, in the forward distribution processing unit 4, broadcast (distribution) content data stored in the content file storage unit 2 is divided by the division processing unit 3 as described above, and the first divided data (identification number “ 1 ”) and the data are sent to the multiplexing unit 6.

  On the other hand, the reverse delivery processing unit 5 performs the split data (identification number) at the end of the file data obtained by dividing the broadcast content file data stored in the content file storage unit 2 by the division processing unit 3. "N") are processed in order and sent to the next multiplexing processing unit 6.

  The forward delivery processing unit 4 including the division processing unit 3 corresponds to the forward processing unit, and the backward delivery processing unit 5 including the division processing unit 3 corresponds to the backward processing unit.

  Here, when the data file (a series of content data) shown in FIG. 6 is divided into fixed lengths (fixed data amount: 1 byte) and mapped to each packet, a FLUTE (File Delivery over Unidirectional Transport) protocol is used. An ID is assigned to an FDT (File Delivery Table) instance packet used in. This is the assignment of the identification numbers (“1” to “N”) of the respective divided data (packets) described above.

  As shown in FIG. 6, file data is divided into fixed lengths (for example, 1 byte), and is transmitted for each block of the divided data (in the example of FIG. 6, four divided data are set as one block). FEC (Forward Error Correction) packets are additionally inserted in order to correct such errors. In the example of FIG. 6, two FEC packets are additionally inserted for each block (one period).

  FIG. 7 shows the structure of the FDT instance packet 30. The FDT instance packet 30 includes a UDP header 31, a default LCT header 32, an LCT header extension 33, an FEC payload ID 34, and file data 35 obtained by dividing a series of data into a fixed length l. The LCT header extension 33 has a data structure as shown in FIG.

  As shown in FIG. 8, the FDT instance ID of the LCT header extension 33 is an ID (identifier) given to the FDT instance packet. This ID corresponds to the identification number of the divided data according to the present invention, and is assigned sequentially from the first divided data as described above, and the initial number identification number “1” to the end packet in ascending order from the first packet. Is given the final identification number “N”.

  The FDT instance ID is assigned when mapping to each packet as shown in FIG. 6, and thereafter, the forward distribution processing unit 4 starts from the first divided file data to which the mapped identification number “1” is assigned. In order, they are sent to the multiplexing unit 6 in ascending order. On the contrary, the reverse delivery processing unit 5 sends the data to the multiplexing unit 6 in descending order in order from the terminal number identification number “N” assigned to the mapped data (packet). In this case, as shown in FIG. 6, following the data at the end of the content file, an FEC packet is added as described above, and an ID with an identification number “N” is similarly given to this FEC packet. Sent to the conversion unit 6.

  The final identification number “N” of the FDT instance ID includes the total size (L bytes) of the file data to be transmitted, the size of the data file divided into a fixed length (1 byte), and the FEC packet additionally inserted as described above. It depends on the number of Here, the FEC packet is a packet inserted to correct an error at the time of transmission, and is inserted at a fixed interval with respect to the FDT instance packet to be transmitted related to the divided data file. If the number of FEC packets that fall between one set of FDT instance packets for K data packets (K = 4 in the example of FIG. 6) is k (k = 2 in the example of FIG. 6), the FDT instance ID The final identification number “N” is obtained by equation (1).

N = L / l × (1 + k / K) −1 (1)
In the above equation (1), when the identification number of the initial number of the first divided data (data packet) is “0” and the initial number is “1”, -1 becomes unnecessary.

  In the example shown in FIG. 6, when the number of packets in one set (FDT instance packet) is K = 4 as described above, the number of FEC packets is k = 2, and the number of data divisions (L / l) is 200, The final identification number “N” is “299” when the initial initial number is the identification number “0”.

  The two systems of MPEG-2TSP (Transport Stream Packet) created by the forward distribution processing unit 4 and the reverse distribution processing unit 5 as described above are transmitted to other channels by the multiplexing unit 6 as independent channel data. And control information such as PMT (Program Map Table) and NIT (Network Information Table). At this time, for example, the initial identification number “1” of the first packet and the final identification number “N” of the last packet are multiplexed at the same time, and are multiplexed in the order of subsequent packet numbers. Then, after OFDM modulation is performed by the transmission path encoding unit 7, the broadcast wave transmission unit 8 transmits (distributes) it to the wireless transmission path 100.

  As described above, a series of content files are divided, and identification numbers of packets (divided data) for connecting the divided data of the content files are given to them. At the same time, various control information necessary for distribution, etc. The added mapping process is performed and transmitted (distributed) via the broadcast wave transmitting unit 8.

(Receiver configuration)
Next, a description will be given of a configuration for receiving and viewing content file data distributed via the above-described content distribution device 1 and restoring the data to be received and viewed by, for example, a mobile terminal device. To do.

  For example, the portable terminal device 10 as the broadcast receiving device is a device as shown in FIG. 2 described above, and the same parts are denoted by the same reference numerals, and the details are omitted.

  For example, the mobile terminal device 10 includes a broadcast wave receiving unit 11 including a tuner as a receiving unit, a distribution data signal in the forward direction for restoring the received signal, and a signal for processing as a distribution data signal in the reverse direction. Branching unit 20 that branches the received signal into two, transmission path decoding circuits (decoding units) 21A and 21B for restoring the branched received signal into forward delivery data and backward delivery data as described above. , Data demodulating circuits (data demodulating units) 22B and 22B, buffers 14A and 14B for temporarily storing the demodulated data described in FIG. 2, IDs added to the divided data, that is, in order of packet identification numbers A rearrangement processing unit 15 for performing rearrangement processing, a storage unit (storage unit) 16 for storing the rearranged divided data, and a series of stored content files Reproduction control unit 17 for data read play viewing, has a configuration including a display unit 18 and an audio output unit 19 for outputting voice, displays an image of the played content.

  Here, the major feature on the receiving device side of the present invention is that both the forward divided data distributed from the distribution device 1 on the broadcasting station (transmitting station) side and the divided data distributed from the reverse direction are simultaneously processed. In other words, there are two systems of transmission line decoding circuits 21A and 21B, data demodulation circuits 22A and 22B, and buffers 14A and 14B for demodulating each received signal. Each of these elements will be described below. The transmission path complex circuit 21A and the data demodulating circuit 22A include the receiving unit 11, and the transmission path complex circuit 21B and the data demodulating circuit 22B perform the data processing in the reverse direction. This corresponds to the second processing unit to be performed.

  The broadcast wave receiver 11 receives a broadcast wave transmitted via the wireless transmission path 100 and converts it into an electrical signal. Here, according to the present invention, the receiving unit 11 includes a signal delivered in the forward direction (ascending order) and a reverse direction (descending order) as described above in the signal delivered (transmitted). Simultaneously receive the signal delivered to. This received signal is branched by the next branching unit 20 and sent to the transmission path decoding units 21A and 21B, respectively. The transmission path decoding units 21A and 21B perform OFDM demodulation on the transmitted signal and extract broadcast data of an arbitrary channel.

  The transmission path complexing unit (first forward processing unit) 21A demodulates the signal sent via the branching unit 20 and extracts data distributed in the forward direction as data of an arbitrary channel. To do. Further, the transmission path complexing unit (second processing unit in the reverse direction) 21B extracts data distributed in the reverse direction as data of an arbitrary channel.

  Then, the data demodulating circuits 22A and 22B decode the broadcast data of the extracted channels, and attach the FDT instance ID, that is, the identification number to the content data divided into the fixed length, and receive the buffers 14A and 14B in the order of reception. Memorize temporarily. The data demodulating circuit (first processing unit in the forward direction) 22A demodulates data in the forward direction, and the data demodulating circuit (second processing unit in the reverse direction) 22B demodulates the data in the reverse direction.

  The demodulated data is restored to a normal series of content file data in the next rearrangement processing unit 14. Therefore, the rearrangement processing unit 14 reads the content data and FDT instance ID (identification number) divided into fixed lengths from the two buffers 14A and 14B as a set, rearranges them in the order of the FDT instance ID numbers, and stores the contents. Part 16 is recorded.

  When recording in the content storage unit 16 is stored in the order of the numbers of FDT instant IDs (identification numbers), there are also items that are not directly related to the data of the content file, that is, FEC packets for correction at the time of transmission. Therefore, it is necessary to process the ID assigned to the FEC packet as a missing number.

  Therefore, the FEC packet identification number (FDT instance ID) is calculated based on the following equation (2) and processed as a missing number.

nFEC = (K + k) × m + (K + x) (2)
In the above formula (2), “nFEC” is an identification number (FDT instance ID) assigned to the FEC packet, “m” is a natural number including “0”, and “x” is the number of data packets K in one set. It is the number of FEC packets added to the number and is an integer from 1 to k. “K” is the number of divided data packets in one set during mapping processing in the content distribution apparatus 1, and “k” is the number of FEC packets inserted into the data packets in one set.

  Therefore, when additional insertion of FEC packets is performed by the mapping process shown in FIG. 6 described above, K = 4 and k = 2. Therefore, the first nFEC is k = 1, 2 when m = 0, and therefore its ID is “5” “6”. This indicates an FEC packet. This is a case where the initial ID number of the first packet is “1”. If the calculation is sequentially performed in the order of m = 1, 2, 3,..., The ID given to the FEC packet can be known, and the FEC packet can be recognized by recognizing the identification number. At the same time, it can be processed as a missing number and recording in the storage unit 16 can be avoided. When the initial identification number is “0”, −1 may be added in the above formula (2).

  Further, in addition to calculating and confirming the ID (nFEC: identification number) of the FEC packet by the above equation (2), it can be recognized by the following method. That is, in each transmitted packet (FLUTE instance packet), as shown in FIG. 6, apart from the series of content file data itself, an FEC packet additionally inserted between these data has been received. By demodulating the data, it becomes clear that it is not content data. At that time, the same processing can be performed with the ID of the packet as a missing number.

  As described above, in the content storage unit 16, the divided data of the sequentially divided contents are rearranged and recorded based on the IDs (identification numbers) of the received various packets. Then, data received in the forward direction from the beginning and data received in the reverse direction from the end are accumulated, and when data relating to all identification numbers is received, a series of broadcast content file data is prepared and accumulated. Part 16 is recorded. A series of broadcast content file data recorded (stored or stored) is requested to start reproduction by a user operation or a timer. In accordance with this request, the playback control unit 17 reads the content file data stored in the content storage unit 16, plays it back as audio or video, and outputs it via the display unit 18 or the audio output unit 19. Thereby, it is possible to view the content desired by the user.

  As described above, the time until the target content is received and all the series of content files are downloaded to the content storage unit 16 is as described with reference to FIG. You can get a download service in time. Moreover, even if it cannot receive from the start of broadcasting, it can receive the download service of all the contents even in the middle of the method.

  In the above description, the control device is not shown, but each component such as various circuits of the distribution device 1 and the reception device (mobile terminal device or the like) 10 is controlled by the control device.

(About content file distribution processing)
Here, according to the mapping process by data division shown in FIG. 6, in addition to the data packet, the FEC packet is inserted through. Therefore, an identification number (ID) is also assigned to an FEC packet that is additionally inserted into the data packet. In the case where the identification numbers are assigned consecutively including this, as shown in FIG. 9, an FEC packet is additionally inserted after the end data of the content file, and the final identification number is assigned to the FEC packet.

  When transmission is performed from the reverse direction, since the packet with the final number “N” is an FEC packet, it cannot be distributed in the reverse direction in order from this packet. Therefore, with respect to delivery from the reverse direction, each packet including FEC packets to be additionally inserted into the number of data packets in one set (K = 4) is set as one block unit, and the delivery process is performed in reverse order in this block unit. To.

  Therefore, as an optimal method, the reverse delivery processing unit 5 shown in FIG. 5 performs the order of the FEC packets to which the final identification number “N” is assigned in the forward direction from the data packet X in the block D1 of the data packet including the end. The data is sent to the multiplexing unit 6. Then, in the next block D2, the data packets T (identification number “N-11”) are sent to the multiplexing unit 6 in the order of the FEC packets to which the identification numbers “N-6” are assigned in the order of the identification numbers. The backward distribution processing unit 5 sequentially repeats the processing for each block unit in the backward direction, that is, toward the top of the content file.

  As described above, distribution processing is sequentially performed in the reverse direction in units of one block shown in FIG. 9, and processing in the forward direction is performed within one block. As a result, the data packet identification number can be distributed by matching the one distributed in the forward direction with the number distributed in the reverse direction.

  The reverse distribution processing unit 5 also performs “N− (K + k) from the identification number calculated by“ N− (K + k) × p + 1 ”of one block in order to perform reverse distribution processing in units of one block. ) × (p−1) ″ in the order of identification numbers calculated in ascending order. Here, p is a natural number including “1”, and is increased from “1” (“2” “3”...) In order from the block D1 (final block) including the end to D2 and D3 in order. That's fine.

(About assigning identification numbers)
Here, according to the description of the above-described embodiment, with regard to the identification number (ID), each mapped data packet includes a FEC packet and a continuous number (initial number “1 or 0” to final number “N”) is used. They are given in order. Instead of such assignment, a serial number is assigned only to those related to the data packet of the content file. For the FEC packet, other numbers, for example, the most significant bit is set to “1000... 0001”. , “1000... 0010”, “1000... 0011”,. In this case, data packets are given numbers such as “0000... 0001”, “0000... 0010”, “0000. According to such numbering, it is possible to easily determine whether the data packet is a content file or an FEC packet by recognizing the most significant bit “1”. Therefore, when the content file is divided, a serial number is assigned, the process of omitting the number is omitted, and the burden on the rearrangement processing unit 15 on the receiving device side is greatly reduced.

  If the identification number is assigned as described above, the content file can be divided and the identification numbers of the divided data packets can be assigned in ascending order and descending order.

  The above description is to eliminate the difference between the identification number in the forward direction and the reverse direction by additionally inserting the FEC packet separately from the data packet when the content file is divided and mapped. In the case where there is no FEC and only data packets are provided, numbering is simply performed in ascending order and descending order with sequential numbers without performing the numbering as described above.

  If the content file is divided by a fixed length (1 byte), there is no problem if the end is fixed length. However, if it is less than the fixed length, the content of the data for each division is the reverse of the forward distribution in the case of reading from the beginning and dividing by fixed length, and the case of reading from the end and dividing by fixed length. Delivery is different. Therefore, if the end is less than the fixed length, padding processing is performed. That is, dummy data ("0" data) having a fixed length is added to the end.

  In addition, when an FEC packet is inserted, in the description of the embodiment, even when K = 4 and the content file cannot be divided by a multiple of 4, padding processing is performed so as to be a multiple of K.

  Including the above processing, if the data file end of the content file can be divided by a fixed length (l) and can be divided by a multiple of K (for example, K = 4), the content file is read from the end and 1 as shown in FIG. Data division, addition of FEC packets, and ID assignment may be performed in units of blocks, and processing may be performed in the forward direction within the block.

  Also, reading is not performed from the block unit but simply from the end, FEC pack addition, and ID assignment are performed. At this time, as for ID assignment, as described above, for divided data packets, if ID assignment is performed in descending order from the last number (N) with a continuous number, the number assigned in ascending order from the initial number from the top And the respective divided data can be matched. In this case, the ID of the added FEC packet may be given a number different from the ID number of the data packet with the most significant bit being “1”.

(About the whole structure in embodiment of this invention)
Conventionally, content file data has been distributed according to a predetermined order.

  On the other hand, according to the present invention, in the download broadcasting service, the content file data is distributed in the reverse order separately from the determined order of the content file data. As a result, the receiving device side processes the data distributed in the reverse direction at the same time as processing the distribution data in the forward direction. For this purpose, two systems of processing units for processing data distributed in the forward direction and the reverse direction are provided. This made it possible to receive download services in a short time, which could not be expected in the past.

  Therefore, in the case of a portable terminal device that can be carried as a receiving device, it is possible to receive the service in a short time and free the remaining time without being forced to stay in a place (position) where it can be received until the delivery time has passed. Can be used for Even if the service is received while moving, the service is completed in a short time, so that the user can move at a receivable position during the time period and can move freely thereafter.

  Further, even after distribution is started, all content file data services can be received. Therefore, if you forget to receive the distribution (broadcasting) service, you can receive the data service of all content files even from the middle.

  In the description of the embodiment of the present invention, the case where wireless distribution (transmission) is performed has been described. However, distribution using wired communication is also possible.

  In addition, the mobile terminal device can be used not only for a mobile phone but also for a PDA (Personal Digital Assistant), a personal computer, etc., and is not limited to a mobile terminal device, but a TV placed at a predetermined position. (VCRs that record and play back content files)

1 Content distribution equipment (broadcasting equipment)
2 Content storage unit (broadcaster side)
3 Division Processing Unit 4 Forward Processing Unit 5 Reverse Processing Unit 6 Multiplexing Circuit (Distribution Unit)
7 Transmission transmitter (distribution unit)
8 Broadcasting wave transmitter (distribution unit)
10 Receiving device (mobile terminal device)
11 Receiver (Receiving means)
12 Tuner (first processing unit)
13 Tuner (second processing unit)
14 Buffer (temporary storage)
15 Sorting processing unit 16 Content storage unit (receiving device side)
17 Playback Control Unit 18 Display Unit 19 Audio Output Unit 20 Separation Processing Unit 21A Forward Decoding Circuit (First Processing Unit)
21B Reverse decoding circuit (second processing unit)
22A Demodulation circuit in the forward direction (first processing unit)
22B Reverse demodulation circuit (second processing unit)
100 Wireless transmission path (distribution path)

Claims (8)

A content distribution device for distributing content files,
A forward processing unit for processing forward from the beginning of the content file,
A reverse processing unit for processing in the reverse direction from the end of the content file,
A content distribution apparatus having a distribution unit for simultaneously distributing the respective processing data from the forward and backward processing units. The forward processing unit divides a series of content files, assigns identification numbers in ascending order from the first divided data to the last divided data,
The backward processing unit divides a series of content files, assigns identification numbers in descending order from the end division data to the top division data,
The content distribution apparatus according to claim 1, wherein the distribution unit sequentially distributes the ascending order divided data and the descending order divided data processed by the forward direction processing unit and the backward direction processing unit.   The content distribution apparatus according to claim 1, wherein the distribution unit wirelessly distributes data. A receiving device for inputting, reproducing and outputting data distributed from the content distribution device according to claim 1,
A first processing unit for receiving and demodulating the distributed data from the beginning,
A second processing unit for receiving and demodulating distributed data from the end;
A rearrangement processing unit that joins and rearranges data from the top and data from the end demodulated by the first and second processing units;
An accumulation unit that sequentially stores the data rearranged by the rearrangement processing unit;
A reproduction control unit for reading and reproducing the content data of the storage unit;
A receiving device. A receiving device for receiving, reproducing and outputting data distributed from the content distribution device according to claim 2,
A first processing unit that receives and demodulates distributed data from the beginning; a second processing unit that receives and demodulates distributed data from the end;
A rearrangement processing unit that sequentially rearranges the divided data from the beginning demodulated by the first and second processing units and the divided data from the end based on an identification number assigned to each divided data;
An accumulation unit for sequentially storing the data rearranged by the rearranging means;
A reproduction control unit for reading and reproducing the content data of the storage unit;
A receiving device.   The receiving device according to claim 4 or 5, wherein the receiving device is portable and includes receiving means capable of receiving distributed data. A content distribution device for distributing content file data;
In a broadcasting system comprising a receiving device for inputting and reproducing data to be distributed,
The content distribution apparatus is the distribution apparatus according to claim 1,
The broadcast system which is a receiving device having the configuration according to claim 4. A content distribution device for distributing content file data;
In a broadcasting system comprising a receiving device for inputting and reproducing data to be distributed,
The content distribution apparatus is the distribution apparatus according to claim 2,
The broadcast system which is a receiving device having the configuration according to claim 5.