JP2005086453A - Method and device for hierarchized data transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow transmission of highly confidential video streams which only specific receivers can decode, to be performed with less processing load and to increase the flexibility of viewing management. <P>SOLUTION: A channel assignment part 106 divides hierarchical coded data into a plurality of areas per hierarchy and assigns different channels to respective data after division. A general list generation part 110 generates a channel list showing a correspondence relation between all data after division and assigned channels. A transmission list generation part 114 generates a specific channel list for transmission from the channel list on the basis of at least one of receiver information, reception right information, and reception device information. A video transmission part 108 transmits respective data after division by corresponding assigned channels, and a list transmission part 116 transmits the generated channel list. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a hierarchical data transmission apparatus and a hierarchical data transmission method that can transmit hierarchical data that can be decoded only by a specific recipient.

  Conventionally, for example, video data transmitted by a video transmission apparatus is usually compressed and encoded below a certain band by the H.261 system or MPEG (Moving Picture Experts Group) system so that it can be transmitted in a certain transmission band. Thus, once encoded video data, the video quality cannot be changed even if the transmission band changes.

  However, with the diversification of networks in recent years, the bandwidth fluctuation of transmission paths is large, and video data that can transmit video of quality suitable for multiple bands is required. Hierarchical coding schemes that can handle multiple bands have been standardized. Among such hierarchical coding schemes, MPEG-4 FGS (Fine Granularity Scalability), which is a scheme having a particularly high degree of freedom regarding band selection, has now been standardized. Video data encoded by MPEG-4 FGS is one basic layer, which is a moving image stream that can be decoded alone, and a moving image stream for improving the decoded moving image quality of the basic layer. It is composed of at least one or more enhancement layers. The basic layer is low-bandwidth and low-quality video data, and an enhancement layer is added to this according to the band, so that a high-quality image with a high degree of freedom is possible.

  In MPEG-4 FGS, it is possible to control the total data size of the enhancement layer to be transmitted and adapt it to various bands, and it is possible to transmit video of quality corresponding to the band.

  When transmitting a video that can be viewed only to a specific viewer (hereinafter referred to as “receiver”) using such a video transmission device, such as a pay TV system that charges for viewing, for example, As shown in the transmission apparatus of Patent Document 1, the data to be transmitted is encrypted and transmitted, and the reception side decrypts the data.

In the transmission apparatus of Patent Document 1, for example, a video signal is encoded separately into low-quality hierarchical data such as a basic layer and high-quality hierarchical data such as an extension layer, and is converted into high-quality hierarchical data by a confidentiality setting device. On the other hand, after encryption with strong confidentiality is performed, both are combined and transmitted as a hierarchical video stream (hierarchical encoded data) to the terminal on the receiver side.
JP-A-8-181966

  However, since the conventional transmission apparatus performs encryption with high confidentiality on the high-quality hierarchical data that is the encoded enhancement layer so that only a specific receiver can view, the encryption is performed. There is a problem that the processing load becomes large and the transmission of the hierarchical video stream becomes slow.

  In addition, in a conventional transmission device, as a method of transmitting video that can be viewed only by a specific receiver, by encrypting an extended layer, which is high-quality hierarchical data, among data divided by layer (layer) Since it is compatible, video that can be viewed and managed for a specific recipient can only be performed in units of enhancement layers. Therefore, since a partial video in each layer cannot be shown to a specific receiver, there is a problem that the degree of freedom of viewing management, that is, management of information disclosed to the specific receiver is lowered.

  The present invention has been made in view of such a point, and can transmit hierarchically encoded data with high confidentiality that can be decoded only by a specific receiver with low processing and freedom of management of disclosed information. An object of the present invention is to provide a hierarchized data transmitting apparatus and a hierarchized data transmitting method capable of increasing the degree.

  The hierarchical data transmission apparatus according to the present invention divides hierarchically encoded data into a plurality of areas for each hierarchy and assigns separate channels to each divided data, and correspondence between the divided data and assigned channels A configuration is employed that includes generation means for generating a list indicating the relationship, data transmission means for transmitting each divided data through a corresponding assigned channel, and list transmission means for transmitting the generated list.

  According to this configuration, the hierarchical encoded data is divided into a plurality of areas for each hierarchy, and a separate channel is assigned to each divided data for transmission, and the correspondence between the divided data and the assigned channel is determined. Since the list shown is generated and transmitted, the hierarchical encoded data can be restored by rearranging the received hierarchical encoded stream (each divided data) only by the specific recipient to whom the list is transmitted, The confidentiality of hierarchically encoded data transmission can be ensured without performing encryption with a heavy processing load.

  In addition, since the hierarchically encoded data that is divided into a plurality of areas for each hierarchy and is transmitted on different channels is restored by using a list, the restored hierarchically encoded data is divided into each divided area unit. It can be partially concealed across layers, and the degree of freedom of management of information disclosed can be increased by decoding the hierarchically encoded data to be transmitted.

  Therefore, when the hierarchically encoded data to be transmitted is hierarchically encoded video data, the hierarchically encoded video data can be decrypted only by a specific recipient of the list transmission destination, and it is possible to conceal without encryption. High-level layered video data transmission can be performed with low processing, and only a specific receiver can decode, and layered video stream transmission can be performed at low speed, that is, with high processing speed and low processing load. In addition, the degree of freedom of viewing management can be increased.

  The hierarchical data transmission apparatus according to the present invention employs a configuration in which, in the configuration described above, the hierarchical encoded data is hierarchical encoded data related to video and / or audio.

  According to this configuration, since the hierarchically encoded data is related to video and / or audio, only a specific recipient of the list transmission destination can decode either or both of video and audio. Without encryption, one or both of the highly confidential video and audio can be transmitted at low speed, that is, at a high speed with less processing load, and freedom of viewing management Can be increased.

  In the above-described configuration, the hierarchical data transmission apparatus according to the present invention employs a configuration in which the assigning unit randomly assigns different channels to each divided data.

  According to this configuration, since the divided data is randomly assigned to different channels, it is much more difficult to predict the correspondence between the divided data and the assigned channel, and is decoded using a list. It is possible to improve the confidentiality of the hierarchically encoded data.

  In the hierarchical data transmission apparatus according to the present invention, in the configuration described above, the generation unit generates a list indicating a correspondence relationship between the divided data corresponding to the disclosureable area and the assigned channel based on predetermined information. Take the configuration. Here, the predetermined information may be, for example, at least one piece of information among receiver information, reception right information, and reception device capability information.

  According to this configuration, in order to generate a list indicating the relationship between the divided data corresponding to the disclosureable area and the allocated channel based on predetermined information, hierarchical encoding is performed on a specific recipient of the list transmission destination. The data can be decrypted so that data corresponding to only the regions that can be disclosed is disclosed.

  In the hierarchical data transmission apparatus according to the present invention, in the configuration described above, the generation unit indicates a correspondence relationship between the divided data corresponding to the hierarchy necessary for receivable quality and the assigned channel based on predetermined information. Use a configuration to generate a list. Here, the predetermined information may be, for example, at least one piece of information among receiver information, reception right information, and reception device capability information.

  According to this configuration, since the list indicating the correspondence between the divided data corresponding to the hierarchy necessary for the receivable quality and the assigned channel is generated based on the predetermined information, the specific reception of the list transmission destination It is possible to allow a person to decode hierarchically encoded data and to disclose data corresponding to only a receivable quality hierarchy.

  In the above-described configuration, the hierarchical data transmission apparatus according to the present invention employs a configuration in which the list transmission unit transmits the generated list using a channel different from the channel assigned to the divided data.

  According to this configuration, since the list is transmitted using a channel different from the channel assigned to the divided data, the confidentiality of the hierarchically encoded data encoded by the specific receiver of the list transmission destination Can be high.

  The hierarchical data transmission method of the present invention divides hierarchically encoded data into a plurality of areas for each hierarchy, assigns separate channels to each divided data, and correspondence between the divided data and assigned channels A generation step for generating a list indicating the relationship, a data transmission step for transmitting each divided data through a corresponding assigned channel, and a list transmission step for transmitting the list generated in the generation step are provided.

  According to this hierarchical data transmission method, hierarchical encoded data is divided into a plurality of areas for each hierarchy, and separate channels are allocated to the divided data, and the divided data is transmitted through the assigned channels. In order to generate and send a list showing the correspondence between the channel and the assigned channel, the list is sent to a specific recipient, so that only the specific recipient can reorder the hierarchically encoded streams (divided data) received Thus, the hierarchically encoded data can be restored, and the hierarchically encoded data can be transmitted while ensuring confidentiality without performing encryption with a heavy processing load.

  In addition, the hierarchically encoded data is transmitted as a data indicating an area obtained by dividing the hierarchy into a plurality of channels, and the receiving side rearranges the divided data divided into a plurality for each hierarchy using a list. Therefore, the hierarchically encoded data restored on the data receiving side can be partially concealed in each layer, and the degree of freedom of management of the part that enables decoding of the hierarchically encoded data is increased. .

  Therefore, when the hierarchically encoded data to be transmitted is hierarchically encoded video data, only a specific recipient can decrypt it, and the highly confidential hierarchical video stream transmission is performed with low processing without encryption. In addition, the degree of freedom of viewing management can be increased.

  As described above, according to the present invention, only specific receivers can decode, and it is possible to perform hierarchically encoded data transmission with high confidentiality with low processing and freedom of management of disclosed information. The degree can be increased.

  The essence of the present invention is that a hierarchically encoded data stream, for example, a hierarchically encoded video stream, is divided into layers and regions and transmitted through different channels, and the divided data and divided data are divided. A list indicating the correspondence relationship with the channels assigned to is generated, and the generated list is transmitted.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, a case where hierarchically encoded video data is transmitted as hierarchically encoded data will be described as an example.

  FIG. 1 is a diagram showing a configuration of a video transmission system including a hierarchical data transmission apparatus according to an embodiment of the present invention.

  The video transmission system shown in FIG. 1 is transmitted from a video transmission apparatus 100 that transmits hierarchically encoded video, a video reception apparatus 150 that receives video transmitted from the video transmission apparatus 100, and a video transmission apparatus 100. A network 180 that relays the video to the video receiver 150. That is, the video transmitted from the video transmission device 100 is transmitted to the video reception device 150 through the network 180.

  The video transmission device 100 includes a video input unit 102, a video encoding unit 104, a channel allocation unit 106, a video transmission unit 108, an entire list generation unit 110, a transmission list generation unit 114, and a list transmission unit 116.

  The video input unit 102 outputs an image that is provided from the outside or generated by the device 100 to the video encoding unit 104 for each frame.

  The video encoding unit 104 hierarchically encodes the image output from the video input unit 102 as an input image, and outputs the obtained hierarchical encoded data to the channel allocation unit 106.

  For example, when MPEG-4 FGS encoding is used, the video encoding unit 104 generates encoded data composed of a base layer (BL) and an extended layer (EL) that improves image quality for an input image. To do. In this case, the image quality can be improved by adding an extension layer to the base layer. In addition, the enhancement layer can divide data from the lower layer, and it is possible to control the degree of quality to be improved by controlling the amount of data added to the base layer.

  The channel allocation unit 106 divides the hierarchically encoded data input from the video encoding unit 104 into a plurality of pixel block data that constitutes a frame for each layer (layer), and each of the divided pixel blocks Separate channel numbers for transmission are allocated and output to the video transmission unit 108. The size of the pixel block is preferably 16 × 16 pixels, for example.

  In this channel allocation unit 106, the channels allocated to the divided pixel block data are randomly allocated using random numbers.

  Further, the channel assignment unit 106 outputs the divided pixel block information, the hierarchy information formed by the pixel block, and the channel number information assigned to the divided pixel block to the entire list generation unit 110. For example, FIG. 2 shows an example in which hierarchically encoded data is divided and different channels are assigned to the divided data.

  FIG. 2 is a diagram illustrating an example in which a channel is assigned to each pixel block of each layer constituting a hierarchically encoded video stream for one frame. In addition, in each layer 200, 300, 400 shown in FIG. 2, the position of each of the pixel blocks 1-20 divided into a plurality is preset in each layer 200, 300, 400.

  Specifically, in the base layer 200 shown in FIG. 2A, the channel 1 is assigned to the pixel block 1 constituting the upper left portion of the frame, and the channel 210 is assigned to the pixel block 2 adjacent to the right of the pixel block 1. Assigned. Further, in the first enhancement layer 300 shown in FIG. 2B, channel 10 is assigned to the pixel block 1, and in the second enhancement layer 400 shown in FIG. 2C, channel 2 is assigned to the pixel block 3. Yes.

  As described above, in each of the layers 200, 300, and 400, a separate channel is assigned to each of the pixel blocks 1 to 20 that configure the respective layers 200, 300, and 400. In FIG. 2, only two enhancement layers are illustrated as enhancement layers constituting an image for one frame, but the present invention is not limited to this, and one enhancement layer may be constituted by any number of enhancement layers.

  The video transmitting unit 108 transmits the divided data output from the channel allocating unit 106 to the network 180 using different allocated channels. Specifically, for example, pixel block data divided in each hierarchy and assigned to different channels for each hierarchy (basic layer and enhancement layer) are transmitted to the network 180 simultaneously on different channels. This transmission is preferably performed by multicast transmission. Here, multicast transmission is a method in which data is transmitted only to a terminal that has selected reception with respect to a channel for transmitting data from one video transmission device. In the case where a plurality of video reception devices perform reception. However, since there is no duplication of data transmitted in the same transmission path, this is a transmission method with good transmission efficiency.

  The overall list generation unit 110 generates an overall channel list indicating the correspondence between all the pixel blocks constituting the frame based on the information obtained when the channel allocation unit 106 divides and assigns the hierarchically encoded data. The generated entire channel list is output to transmission list generating section 114.

  The entire channel list is a table in which the channel allocation unit 106 stores the pixel block number, the layer number formed by each pixel block, and the allocated channel number in association with each other.

  The entire channel list can be decoded and displayed as a normal image by rearranging the pixel block data divided and transmitted for each different channel by the video transmission unit 108.

  An example of the generated channel list is as shown in FIG. 3, for example. As shown in FIG. 2, the channel list 120 shown in FIG. 3 shows an example of the channel list 120 when a channel is assigned to each pixel block of a layer constituting one frame of an image.

  The overall channel list 120 shows the divided pixel block numbers, the layer names formed by the pixel blocks, and the channel numbers assigned to the pixel blocks. Specifically, data of block 1 of the base layer is transmitted on channel (CH) 1, data of pixel block 3 of the second enhancement layer is transmitted on channel (CH) 2, and data is transmitted on channel (CH) 10. It shows that data of pixel block 1 of one enhancement layer is transmitted and data of pixel block p of n layer is transmitted through channel (CH) m. Note that the overall channel list 120 is not limited to that shown in FIG. 3, and may be any channel that shows the channels allocated to each divided pixel block and the layers that the pixel block configures.

  The transmission list generation unit 114 generates a transmission channel list indicating a correspondence relationship between a pixel block corresponding to an openable area and an allocated channel based on predetermined information. In addition, the transmission list generation unit 114 generates a transmission channel list indicating a correspondence relationship between pixel blocks corresponding to layers necessary for receivable quality and assigned channels. Specifically, all pixel blocks (images) to which all channels are allocated, generated by the entire list generation unit 110 based on the receiver information, receiver right information, and capability information of the video receiving device, which are predetermined information. A transmission channel list for extracting only a pixel block suitable for a specific receiver from a whole channel list having a base layer constituting the frame and all pixel blocks for each of a plurality of enhancement layers, and transmitting to the specific receiver Is generated and output to the list transmission unit 116.

  The receiver information is information for setting a video that can be displayed on the receiver side in accordance with a request of a specific receiver. For example, information set as non-disclosure data based on the relationship with a specific recipient can be cited. In this way, as the information of the display form desired by a specific receiver, for example, only a part of the image of a predetermined person's face for privacy protection in a part of the image displayed in a plurality of layers, for example, the basic layer. This is a case where the display is not displayed. In this case, the transmission list generation unit 114 generates a transmission channel list by removing the pixel block that is an image corresponding to only a part from the entire channel list having all the pixel block information. Specifically, when a video displayed in a plurality of layers is a monitoring video, a predetermined portion in the video, for example, the face of a monitoring person is not partially displayed.

  The receiver right information is information for setting a video that can be displayed in accordance with a request from a specific receiver. For example, when the receiver right information is information set according to the contents of the reception contract with the receiver, the transmission list generation unit 114 selects only the pixel blocks constituting the layer set with the contents of the reception contract from the entire channel list. To generate a transmission channel list. For example, the number of enhancement layers included in the transmission channel list is increased according to the billing stage.

  Furthermore, the capability information of the video receiving device is device capability information indicating the capability of the video receiving device 150. As the device capability information, for example, when it is the size of the display screen, the transmission list generation unit 114 configures a layer of a size that can be displayed by the video reception device 150 from the entire channel list according to the size of the display screen. A pixel block to be extracted is extracted to generate a transmission channel list.

  The predetermined information is provided to the video transmission apparatus 100 from the receiver side. As the method, for example, the video expression form desired by the receiver may be transmitted to the video transmission side using a telephone, mail, or the like, and the video transmission device 100 is accessed from the receiver side device. Then, the receiver information and the reception right information may be configured to be inputable, and a list to be transmitted to the receiver may be generated based on the input data.

  The list transmission unit 116 transmits the generated transmission channel list to the network 180 through a channel different from the channel for transmitting data. Another channel for list transmission is for transmission only to the video receiver 150 of a specific recipient, and may be a channel designated by the receiver to the video transmitter 100 at the time of list transmission.

  On the other hand, the video reception device 150 includes a list reception unit 152, a video reception unit 154, a video decoding unit 156, and a video display unit 158.

  The list receiving unit 152 receives a transmission channel list transmitted on another channel for the list on the network, and transmits it to the video receiving unit 154.

  The video reception unit 154 receives the hierarchically encoded video stream transmitted from the video transmission apparatus 100, receives pixel blocks that are video data that can be received using a transmission channel list, from each corresponding channel, and receives them. The data is output to the video decoding unit 156.

  Specifically, the video reception unit 154 receives the pixel block number indicated in the transmission channel list received by the list reception unit 152 from the list transmission unit 116 of the video transmission device 100, the layer formed by the pixel block, Based on the channels assigned to the pixel blocks, the pixel block data received through the respective channels is rearranged to obtain hierarchically encoded video data before being divided by the video transmission device 100, and output to the video decoding unit 156 To do.

  The video decoding unit 156 decodes the video data (encoded data) output from the video receiving unit 154, and outputs the video obtained by decoding to the video display unit 158.

  The video display unit 158 displays the video output from the video decoding unit 156 on the screen. The video display unit 158 includes a display device.

  Next, the operation of the video transmission apparatus 100 having the above configuration will be described. Note that the transmission processing of the hierarchically encoded video data in the video transmission device 100 is stored as a control program in a storage device (not shown) (for example, a ROM or a flash memory), and is also executed by a CPU (not shown).

  First, the video input unit 102 outputs an image constituting the video to the video encoding unit 104 for each frame.

  The video encoding unit 104 performs video encoding processing. Specifically, hierarchical encoding is performed on the input video from the video input unit 102 to generate encoded data including a base layer and an enhancement layer, and output to the channel allocation unit 106.

  The channel allocating unit 106 divides the input hierarchical encoded video data into a plurality of pixel blocks for each layer, and randomly allocates a channel for transmission for each divided pixel block, and the video transmitting unit 108 Output to. Further, for each divided pixel block, the layer information formed by the pixel block and the information on the channel (allocated channel) allocated to the pixel block are output to the entire list generation unit 110.

  The video transmission unit 108 performs video transmission processing. Specifically, the data for each of the plurality of pixel blocks output from the channel assignment unit 106 is multicast-transmitted to the network 180 through a corresponding separate assignment channel.

  In addition, the entire list generation unit 110 divides the information input from the channel allocation unit 106, that is, the divided pixel block information based on the layer information that the pixel block configures and the information on the channel that is allocated to the pixel block. The generated pixel block and the layer formed by the pixel block are associated with the channels assigned to the pixel block, and an entire channel list of the entire hierarchically encoded frame indicating the relationship is generated to generate a transmission list. Output to the unit 114.

  Based on at least one of the receiver information, the receiver right information, and the device capability information of the receiving device, the transmission list generating unit 114 matches the receiver with the entire channel list generated by the entire list generating unit 110. Then, a transmission channel list including pixel block information that can be disclosed and pixel blocks that form a layer necessary for receivable quality is generated and output to the list transmission unit 116. The transmission channel list generated by the transmission list generation unit 114 defines the video to be displayed on the video receiving device 150, and is set by the receiver information, the receiver right information, and the device capability information of the receiving device.

  When the receiver is allowed to view all of the hierarchically encoded video, all the pixel blocks indicated by the entire channel list become disclosing pixel blocks, and therefore the entire channel list generated by the entire channel list is transmitted channel list. To the list transmission unit 116.

  On the other hand, it is possible to set so that only a part of the hierarchically encoded video can be viewed. An example is shown in FIG. FIG. 4 is a diagram illustrating an example of a display screen on which only a part of a video composed of the base layer 200, the first enhancement layer 300, and the second enhancement layer 400 (see FIG. 2) is displayed.

  The video frame 500 shown in FIG. 4 does not display the central area 501 but displays the surrounding area 502. In this case, the information of the pixel blocks 6, 7, 10, and 11 constituting the central region 501 in each layer 200, 300, and 400 is removed from the transmission channel list, and the other region 502 is included in each layer 200, 300, and 400. It becomes possible by extracting only the information of the pixel blocks 1 to 4, 5, 8, 9, 12, and 13 to 20 constituting the information into the specific list. Also, select some pixel blocks of the base layer 200, some pixel blocks of the first enhancement layer 300, and some pixel blocks of the second enhancement layer 400, respectively, from the entire channel list. By omitting the generation of the transmission channel list, a part of the frame area straddling each layer 200, 300, 400 may be displayed, or conversely, a part of the frame area may not be displayed. It becomes possible.

  As a result, for example, even when the displayed video is a form in which only a part of the video of the face of a predetermined person is not displayed for privacy protection, the transmission list generation unit 114 determines that the video corresponding to only a part of the video is displayed. This pixel block can be dealt with by generating a transmission channel list by removing it from the entire channel list having all pixel block information.

  Furthermore, another example will be described in which settings are made so that only a part of a hierarchically encoded video can be viewed. For example, when used in a system that involves charging such as pay TV broadcasting that charges for viewing of hierarchically encoded video transmitted from the video transmission device 100, the predetermined information is set according to the contents of the reception contract with the receiver Information and the contents of the reception contract can be increased so that the number of decodable enhancement layers is increased according to the charge. As the number of extension layers is increased in this way, the resolution of video displayed based on each of these layers also increases. That is, when the transmission list generation unit 114 generates a transmission channel list from the entire channel list indicating the entire frame generated by the entire list generation unit 110 according to the reception contract contents, the layer set in the reception contract contents is set. By extracting only the constituent pixel blocks from the entire channel list and changing the number of enhancement layers to be included in the transmission channel list, it becomes possible to manage receivers according to video quality.

  Furthermore, an example in which only a part of the hierarchically encoded video is viewed is set based on the capability information of the video receiving device 150 used by the receiver. For example, when the device capability information is the size of the display screen, the transmission channel list is extracted by extracting pixel block information constituting a layer of a size that can be displayed by the video reception device 150 from the entire channel list according to the display screen. Can be generated, and a suitable video can be displayed on the reception video device 150.

  The list transmission unit 116 transmits the transmission channel list to a video receiver 150 of a specific recipient through a channel different from the channel for transmitting image data.

  Next, the operation of the video receiving apparatus 150 having the above configuration will be described. Note that the reception processing of the hierarchically encoded video data in the video receiver 150 is stored as a control program in a storage device (not shown) (for example, a ROM or a flash memory), and is also executed by a CPU (not shown).

  First, the receiver gives information such as receiver information and reception right information to the video transmitting device 100 side, and sets a video portion that can be displayed on the video receiving device 150, that is, a video portion constituted by pixel blocks. .

  When the video reception unit 154 performs video reception processing, it receives the hierarchically encoded data transmitted from the video transmission apparatus 100 through the assigned channel, receives the transmission channel list, and is shown in the transmission channel list. Based on the correspondence between the pixel block, the layer formed by the pixel block, and the channel assigned to the pixel block, the data input from the channel corresponding to the channel number is rearranged and output to the video decoding unit 156. .

  Then, the video decoding unit 156 performs video decoding processing. Specifically, the video data (encoded data) output from the video receiving unit 154 is decoded, and the video obtained by decoding is output to the video display unit 158.

  Then, the video display unit 158 performs video display processing. Specifically, the video output from the video decoding unit 156 is displayed on the screen.

  According to the present embodiment, the channel allocation unit 106 divides the hierarchically encoded data into a plurality of pixel blocks for each layer 200, 300, 400, and a plurality of divided pixel blocks indicating a plurality of pixel block areas. A separate channel is allocated to each of the video and the video transmission unit 108 transmits the channel to the video reception device 150. Also, the pixel block indicated by the pixel block data divided by the channel assignment unit 106, the layers 200, 300, 400, and the channels assigned to the pixel blocks 1 to 20 included in the pixel block are associated with each other. Generate a channel list.

  Then, from this generated entire channel list, a transmission channel list including pixel block data that can be disclosed in accordance with the receiver is generated and transmitted to the video reception device 150, so that only a specific receiver can transmit the transmission channel list. Using the video receiving device 150, the hierarchically encoded video data can be restored by rearranging the received hierarchically encoded video stream, and the confidentiality can be ensured without performing encryption with a heavy processing load. be able to.

  The hierarchically encoded video data is transmitted on separate channels 1 to m as data indicating pixel blocks obtained by dividing each of layers 200, 300, and 400 and layers 200, 300, and 400, and is received on the video receiver 150 side. Since the entire block list can be used to restore the pixel blocks 1 to 20 divided into a plurality of layers for each of the layers 200, 300, and 400, the hierarchical coded video restored in the video receiver 150 can be restored. Data can be partially concealed in each of the layers 200, 300, and 400, and the degree of freedom in managing a region where a hierarchically encoded video stream can be decoded is increased.

  In this way, only a specific recipient can decrypt the data, and the hierarchically encoded video stream transmission can be performed with low processing without encryption, that is, the processing load can be reduced and high-speed processing can be performed. The degree of freedom of management can be increased.

  In addition, according to the present embodiment, each of the layers 200, 300, and 400 is divided into a plurality of pixel blocks 1 to 20 that are divided for each layer and each of the layers constitutes a random channel. The prediction of the correspondence between the pixel blocks 1 to 20 and the channel in the above becomes much more difficult, and the confidentiality of the hierarchically encoded video data decoded using the list can be further improved.

  According to the present embodiment, information set based on a contract with the user of the video receiving device, information set based on a specific receiving right, or the data receiving device by the transmission list generating unit 114 In order to generate a transmission channel list by extracting region information that can be disclosed to the video reception device 150 from the entire channel list generated by the entire list generation unit 110 using information set based on the device capability of By using the transmission channel list for a specific receiver who has a reception contract, the specific receiver can decrypt the divided data according to the specific receiver.

  Furthermore, since the entire channel list is transmitted to the data receiving apparatus using a channel different from the channel assigned to the divided data, the confidentiality of the hierarchically encoded data for a specific receiver can be increased. it can.

  In the present embodiment, the transmission list generation unit 114 is configured to output the generated transmission channel list to the list transmission unit 116 and transmit the generated transmission channel list to the receiver-side video reception device 150. Not limited to this, the transmission channel list generated by the transmission list generation unit 114 is recorded on a recording medium (for example, floppy (R) disk: Floppy (R) Disk, MO: Magneto Optical, CD-ROM: Compact Disc ROM). Then, it may be delivered to the recipient by mail.

  In the present embodiment, the entire channel list is generated for each frame together with the hierarchically encoded video stream for one frame to be transmitted to the video receiver 150, and transmitted to a specific receiver. However, the present invention is not limited to this, and an entire channel list corresponding to a plurality of frames may be generated and transmitted to a specific recipient before transmitting a hierarchically encoded video stream. As a result, a specific receiver can decode a hierarchically encoded video stream comprising a plurality of video frames using the previously received entire channel list.

  In the present embodiment, the hierarchically encoded video stream (specifically, the hierarchically encoded data stream of video according to MPEG4-FGS), which is hierarchically encoded data related to video, has been described as an example of hierarchically encoded data. However, the present invention is not limited to this, and the hierarchically encoded data may be data of only audio data that has been hierarchically encoded, or hierarchically encoded data related to video and audio. In this way, the same effect can be obtained for audio-only hierarchical encoded data or audio and video hierarchical encoded data.

  The hierarchical data transmission apparatus and hierarchical data transmission method according to the present invention can be decoded only by a specific receiver, can perform hierarchical video stream transmission with low processing, and increase the degree of freedom of viewing management. This is useful for transmitting hierarchically encoded data that can be decoded only by a specific receiver.

The figure which shows the structure of the video transmission system containing the hierarchical data transmission apparatus which concerns on one embodiment of this invention The figure which shows an example which allocated the channel for every pixel block of each layer Figure showing an example of the entire channel list Figure showing an example of the display screen

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Video transmission apparatus 104 Video encoding part 106 Channel allocation part 108 Video transmission part 110 Whole list generation part 114 Transmission list generation part 116 List transmission part

Claims (8)

An assigning unit that divides hierarchically encoded data into a plurality of areas for each hierarchy, and assigns different channels to each divided data;
Generating means for generating a list indicating the correspondence between the divided data and the assigned channels;
Data transmission means for transmitting each divided data through a corresponding assigned channel;
A list transmission means for transmitting the generated list;
A hierarchical data transmission apparatus comprising: The hierarchically encoded data is hierarchically encoded data relating to video and / or audio.
The hierarchical data transmission apparatus according to claim 1. The assigning means includes
A separate channel is randomly assigned to each divided data.
The hierarchical data transmission apparatus according to claim 1. The generating means includes
Based on the predetermined information, a list indicating the correspondence relationship between the divided data corresponding to the disclosureable area and the allocated channel is generated.
The hierarchical data transmission apparatus according to claim 1. The generating means includes
Based on the predetermined information, a list indicating the correspondence relationship between the divided data corresponding to the hierarchy necessary for receivable quality and the allocated channel is generated.
The hierarchical data transmission apparatus according to claim 1.   6. The hierarchical data transmission apparatus according to claim 4, wherein the predetermined information is at least one of receiver information, reception right information, and capability information of the reception apparatus. The list transmission means includes
Send the generated list using a channel other than the channel assigned to the divided data.
The hierarchical data transmission apparatus according to claim 1. An allocation step of dividing the hierarchically encoded data into a plurality of areas for each hierarchy, and assigning different channels to each divided data;
A generation step for generating a list indicating the correspondence between the divided data and the assigned channels;
A data transmission step of transmitting each divided data through a corresponding assigned channel;
A list transmission step for transmitting the list generated in the generation step;
A hierarchical data transmission method characterized by comprising:

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