JP5293670B2 - Information processing apparatus, information processing program, information processing method, and distribution system - Google Patents

Description

  The present invention relates to a technical field of a Peer to Peer (P2P) type distribution system including a plurality of node devices that can communicate with each other via a network.

  In recent years, in a peer-to-peer type distribution system, a distribution system is known in which each piece of divided content data obtained by dividing one piece of content data is distributed and stored in a plurality of node devices (see Patent Document 1). The data amount of one divided content data is, for example, several megabytes. Hereinafter, the content data is referred to as “content”. In the distribution system disclosed in Patent Document 1, a unique content ID is assigned to each divided content. Each node device can acquire divided content in units of divided content from other node devices based on the content ID of the divided content.

Japanese Patent Laid-Open No. 2008-047065

  Incidentally, content created by, for example, SWF (Shockwave Flash), HTML (Hyper Text Markup Language), or the like is composed of a plurality of contents. The content composed of a plurality of contents in this way is hereinafter referred to as “composite content”. In addition, each content constituting the composite content is hereinafter referred to as “sub-content”. The composite content may be composed of a plurality of sub contents having a file size of 1 kbyte or less and sub contents having a file size of about several megabytes to several gigabytes. When such composite content is input to a peer-to-peer distribution system, it is assumed that a unique content ID is assigned to each sub-content, as in the case of the divided content.

  In this case, when reproducing the composite content, the node device acquires each sub-content from a plurality of other node devices based on the content ID. However, in a peer-to-peer distribution system, even sub-contents with a small file size are managed as one content. For this reason, there is a problem in that the total amount of messages transmitted and received when the node device acquires sub-contents or stores sub-contents increases, thereby reducing network utilization efficiency.

  Accordingly, the present invention has been made in view of the above problems and the like, and is an information processing apparatus and information capable of improving the network utilization efficiency even when composite content is input to a distribution system. It is an object to provide a processing program, an information processing method, a distribution system, and the like.

In order to solve the above-mentioned problem, the invention according to claim 1 is characterized in that content data is stored in one or more information processing devices in an overlay network composed of a plurality of information processing devices that can communicate with each other via a network. Information in a distribution system that is stored and configured so that each information processing device acquires the content data from another information processing device connected to the overlay network based on unique identification information given to the content data A processing device for generating composite content data composed of a plurality of content data, and generating a metafile for searching content data constituting the composite content data acquired by the acquisition means It means a compound content data obtained by the obtaining means Data amount of each content data constituting the, determination means for determining less or not than a predetermined amount of data, from a plurality of content data among which is determined to be smaller than the predetermined amount of data by said judging means, one Determining means for determining the content data to be collected in the data, a first assigning means for assigning unique identification information to the chunk in which the content data determined by the determining means are combined into one, and the content data determined by the determining means First description describing offset information indicating the data position of the content data from the beginning in the chunk and unique identification information given to the chunk by the first assigning means in the metafile And content determined to be not smaller than a predetermined amount of data by the determination unit. A dividing unit that divides data by the predetermined data amount, a second adding unit that assigns unique identification information to each chunk using each content data divided by the dividing unit as a chunk, and the dividing unit Second description means for describing, in the metafile, reproduction order information indicating the reproduction order between the content data, and unique identification information given to the chunk by the second assignment means, the offset information, and the reproduction order information, and a third assigning means for assigning identification information specific to the metafile said identification information is written, and the chunk the identification information is given by the first applying means, by said second application means The chunk to which the identification information is assigned and the metafile to which the identification information is assigned by the third granting unit Publishing means for publishing to the overlay network as content data that can be acquired from the information processing apparatus.

  According to a second aspect of the present invention, in the information processing apparatus according to the first aspect, the selecting means for selecting content data based on a predetermined rule from a plurality of content data constituting the composite content data; Comparing means for comparing the total amount of the content data selected by the selecting means with a preset threshold each time the content data is selected by the selecting means, the determining means Is characterized in that, based on the comparison result by the comparison means, a plurality of content data are determined such that the sum of the data amount of the content data falls within a preset threshold value.

  According to a third aspect of the present invention, in the information processing apparatus according to the second aspect, the selection unit selects the content data in descending order of the data amount determined by the determination unit. .

  According to a fourth aspect of the present invention, in the information processing apparatus according to the second aspect, the content data constituting the composite content data are associated in the order of output, and the selection means outputs the output The content data is selected in order.

  According to a fifth aspect of the present invention, in the information processing apparatus according to the second aspect, the content data constituting the composite content data are associated with each other in a hierarchical structure, and the selection means includes a lower hierarchy of the hierarchical structure. The content data located at is preferentially selected.

  According to a sixth aspect of the present invention, in the information processing device according to the first aspect, the content data constituting the composite content data are associated with each other in a hierarchical structure, and the determining means A plurality of pieces of content data associated with each other in a hierarchical relationship are determined as a plurality of pieces of content data to be combined into one.

According to a seventh aspect of the present invention, content data is stored in one or more information processing devices in an overlay network composed of a plurality of information processing devices that can communicate with each other via a network. A computer included in the information processing apparatus in the distribution system configured to acquire the content data from another information processing apparatus connected to the overlay network based on the unique identification information given to the content data, Acquiring composite content data composed of a plurality of content data , generating a metafile for searching content data constituting the acquired composite content data, and acquiring the acquired composite content data Data of each content data to configure But determining whether less than a predetermined amount of data, from a plurality of content data among it is determined that the smaller than the predetermined data amount, determining a content data summarized in one, is the determined A first assigning step for assigning unique identification information to the chunks in which the content data are grouped together, and offset information of the determined content data indicating the data position of the content data from the beginning in the chunk A first description step that describes offset information and unique identification information given to the chunk in the first granting step in the metafile; and content data determined not to be smaller than the predetermined data amount Dividing by the amount of data, and each of the divided content data A second assigning step for assigning unique identification information to each chunk as a chunk, reproduction order information indicating a reproduction order between the divided pieces of content data, and a unique assignment given to the chunk by the second assigning step A second description step of describing identification information in the metafile; a third adding step of adding unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described; The chunk to which the identification information is assigned by the first granting step, the chunk to which the identification information is given by the second granting step, and the metafile to which the identification information is given by the third granting step. To the overlay network as content data that can be acquired from other information processing devices. An information processing program for executing the opening step.

According to an eighth aspect of the present invention, content data is stored in one or more information processing devices in an overlay network composed of a plurality of information processing devices that can communicate with each other via a network. An information processing method in a distribution system configured to acquire the content data from another information processing device connected to the overlay network based on unique identification information given to the content data, Acquiring composite content data composed of content data, generating a metafile for searching content data constituting the acquired composite content data, and configuring the acquired composite content data The amount of data for each content data One determining whether less or not than the amount from the plurality of content data among it is determined that the smaller than the predetermined data amount, determining a content data are summarized in one, the determined content data A first granting step for assigning unique identification information to the chunks grouped together , offset information indicating the determined content data offset information indicating the data position of the content data from the top in the chunk, and A first description step in which the unique identification information given to the chunk in the first granting step is described in the metafile, and content data determined not to be smaller than the predetermined data amount are divided by the predetermined data amount And each divided content data as a chunk A second assigning step for assigning unique identification information to the chunk, reproduction order information indicating the reproduction order between the divided pieces of content data, and unique identification information assigned to the chunk by the second assigning step. A second description step described in the metafile; a third assignment step of assigning unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described; and the first assignment The chunk to which the identification information is assigned in the step, the chunk to which the identification information is assigned by the second grant step, and the metafile to which the identification information is assigned by the third grant step Publishing to the overlay network as content data obtainable from the information processing apparatus , Including.

The invention according to claim 9 includes a plurality of information processing apparatuses capable of communicating with each other via a network, wherein content data is stored in one or more information processing apparatuses, and each information processing apparatus is assigned to the content data. In a distribution system configured to acquire content data from another information processing device based on unique identification information, the first information processing device acquires composite content data including a plurality of content data. First acquisition means, generation means for generating a metafile for searching for content data constituting the composite content data acquired by the first acquisition means, and composite content data acquired by the first acquisition means A determination method for determining whether or not the data amount of each piece of content data is smaller than a predetermined data amount When, together from a plurality of content data among which is determined to be smaller than the predetermined amount of data by the determination means, determining means for determining a content data summarized in one, the one content data determined by said determining means First giving means for giving unique identification information to the chunk , offset information of the content data determined by the determining means, the offset information indicating the data position of the content data from the head in the chunk, and A first description unit describing unique identification information given to the chunk by the first grant unit in the metafile; and content data determined by the determination unit not to be smaller than a predetermined data amount as the predetermined data. Dividing means for dividing by quantity, and each content divided by the dividing means Second giving means for assigning unique identification information to each chunk using the data as a chunk, reproduction order information indicating the reproduction order between the content data divided by the dividing means, and the chunk by the second giving means Second description means for describing the unique identification information assigned to the metafile, and second identification means for assigning unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described. 3 and applying means, the chunk the identification information is given by the first application means, and the chunk said identification information is assigned by the second application means, the identification information provided by said third applying means The published metafile is published to the overlay network as content data that can be acquired from another information processing apparatus. A second acquisition unit configured to acquire the metafile from another information processing device based on the unique identification information given to the metafile , and the second information processing device . Third acquisition means for acquiring the chunk from another information processing apparatus based on the identification information described in the metafile acquired by the acquisition means, and content data constituting the chunk acquired by the third acquisition means Playback means for playing back the video based on the offset information or the playback order information described in the metafile .

  According to the first, seventh to ninth aspects of the present invention, content data with a small amount of data is collected as one content data, put into the overlay network, and released. Therefore, even when composite content data is acquired, by collecting content data with a small data capacity into one, it is possible to suppress the total amount of various messages that fly over the overlay network, and to increase the use efficiency of the network.

  According to the second aspect of the present invention, it is possible to efficiently combine the contents data as one piece of content data so that the total amount of the contents data falls within a preset threshold value.

  According to the third aspect of the present invention, it is possible to combine the contents data as a single piece of content data with more efficient and simple implementation.

  According to the fourth to sixth aspects of the present invention, when the composite content data is reproduced, the content data constituting the composite content data can be acquired more quickly.

It is a figure showing an example of outline composition of a contents distribution system concerning this embodiment. It is a block diagram which shows the example of an outline structure of content management server MS. It is a block diagram which shows the example of schematic structure of the node Nn. It is a flowchart which shows the injection | throwing-in process of the composite content in the control part 1 of content management server MS. It is a flowchart which shows the chunking process in Example 1. FIG. FIG. 6 is a flowchart showing details of sub-content division processing in step S222 shown in FIG. 5. FIG. It is a flowchart which shows the chunking process in Example 2. (A) is a conceptual diagram which shows a mode that the some sub content linked | related by hierarchical structure is chunked. (B) is a figure which shows an example of the information of the sub content described in the data part of the produced | generated metafile. It is a flowchart which shows the reproduction | regeneration processing of the composite content in the control part 11 of the node Nn.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiment described below is an embodiment when the present invention is applied to a content distribution system.

[ 1. Content distribution system configuration and operation overview ]
First, with reference to FIG. 1, the structure and operation | movement outline | summary of the content delivery system which concerns on this embodiment are demonstrated. FIG. 1 is a diagram illustrating a schematic configuration example of a content distribution system according to the present embodiment.

  As shown in FIG. 1, a content distribution system S according to the present embodiment includes a content management server MS, a content provider management terminal Tm, and a plurality of node devices Nn (n = 1, 2, 3,... K). Etc. are provided. The content management server MS, the content provider management terminal Tm, and each node device Nn are connected to a network NW such as the Internet. The node device is hereinafter referred to as “node”. Each node Nn is assigned a node ID that is unique identification information. The content management server MS is an example of the information processing apparatus or the first information processing apparatus in the present invention. The node Nn is an example of a second information processing apparatus in the present invention.

  In the content distribution system S, an overlay network ON is formed. The overlay network ON is a logical network that forms a virtual link including a plurality of nodes Nn that can communicate with each other via the network. The overlay network ON is realized by a specific algorithm, for example, an algorithm using a distributed hash table. Hereinafter, the distributed hash table is referred to as “DHT (Distributed Hash Table)”. Note that a routing table using DHT is known in Japanese Patent Application Laid-Open No. 2006-197400 and the like, and thus detailed description thereof is omitted.

  Then, the content management server MS inputs the content uploaded from, for example, the content provider's management terminal Tm into the content distribution system S. Here, the input of content refers to saving new content in one or more nodes Nn participating in the overlay network ON. The node Nn that stores the content is hereinafter referred to as a “content holding node”. Each input content is given a content ID which is unique identification information. Each node Nn can acquire the content stored in the other node Nn via the overlay network ON based on the content ID. The content acquired in this way is stored in the node Nn. Thus, the content is distributed and stored in a plurality of content holding nodes in the overlay network ON.

  Further, content having a file size larger than a predetermined data amount is divided for each size equal to or smaller than the predetermined data amount. As a result, a plurality of chunks are generated. Here, the predetermined data amount is hereinafter referred to as “threshold value”. The file size represents the data amount of content. The chunk is composed of a header part and a data part. The header part includes a chunk ID, which is identification information unique to the chunk, and the chunk file size. The data portion includes divided data. Then, the chunk is input into the content distribution system S as one content. Each node Nn can acquire a chunk from another node Nn via the overlay network ON based on the chunk ID.

  On the other hand, composite content composed of a plurality of sub-contents may be input to the content distribution system S. In this case, one sub-content can be thrown into the content distribution system S as one chunk. However, if sub-contents having a file size of 1 kbyte or less, for example, are used as one chunk, the use efficiency of the network NW is lowered as described above. For this reason, in the present embodiment, a plurality of sub contents having a file size of, for example, 1 kbyte or less are collected and input as one chunk. In addition, the sub-content whose file size is larger than the threshold value is divided into a plurality of chunks and then input into the content distribution system S. In the following description, the term “content” simply includes both composite content and normal content other than composite content.

  By the way, the chunk ID of each chunk constituting the content is described in, for example, a metafile of the content. The content metafile is a file for searching for each chunk constituting the divided content. In the content metafile, information indicating the correspondence between each chunk in the content is described in association with the chunk ID. The information indicating this correspondence is represented by, for example, the playback order of each chunk in the content or the number of bytes at the head position of each chunk. Then, the content metafile is input into the content distribution system S as one content. The input metafile is given a content ID corresponding to the metafile. Therefore, each node Nn can acquire a metafile of content from another node Nn via the overlay network ON based on the content ID. Note that the node ID, content ID, and chunk ID are generated by hashing with a common hash function, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2006-197400.

  Information indicating the location of the content, the location of the content metafile, or the location of the chunk is stored as index information in the node Nn that manages the location of the content. The node Nn that manages the location of the content is hereinafter referred to as a “root node”. This index information includes a set of node information of a content holding node that stores content or a content metafile and a content ID of the content or content metafile. Alternatively, the index information includes a set of node information of the content holding node that stores the chunk and a chunk ID of the chunk. The node information includes the IP address, port number, and node ID of the content holding node. For example, the root node is determined to be the node Nn to which the node ID closest to the content ID or the chunk ID is assigned. The node ID closest to the content ID or chunk ID is, for example, the node ID with the highest number of upper digits that match.

[ 2. Configuration and function of content management server MS ]
Next, the configuration and function of the content management server MS will be described with reference to FIG.

    FIG. 2 is a block diagram illustrating a schematic configuration example of the content management server MS.

  As shown in FIG. 2, the content management server MS includes a control unit 1, a storage unit 2, a communication unit 3, and the like. The control unit 1, the storage unit 2, and the communication unit 3 are connected to each other via a bus 4.

  The storage unit 2 is composed of, for example, a hard disk drive. The storage unit 2 stores an operating system, an information processing program, and the like. Note that the information processing program may be downloaded from a predetermined server connected to the network NW, for example. Alternatively, the information processing program may be recorded on a recording medium and read via a drive of the recording medium, for example.

  The storage unit 2 stores content catalog information including content records. In the content record, the content ID, content name, keyword, and the like of the content are described. The content record is generated when the content is input into the content distribution system S. Then, the content catalog information including the generated record is distributed from the content management server MS to each node Nn.

  The information described in the content metafile may be configured to be described in the content record. In this case, it is not necessary to input the content metafile into the content distribution system S. The communication unit 3 controls communication of information with the node Nn and the like through the network NW.

  The control unit 1 includes a CPU having a calculation function, a working RAM, a ROM, and the like. And the control part 1 performs the process mentioned later, when CPU reads and runs the information processing program memorize | stored in the memory | storage part 2 grade | etc.,. The control unit 1 is an example of an acquisition unit, a determination unit, a determination unit, a grant unit, a disclosure unit, a selection unit, and a comparison unit in the present invention.

[ 3. Configuration and function of node Nn ]
Next, the configuration and function of the node Nn will be described with reference to FIG.

  FIG. 3 is a block diagram illustrating a schematic configuration example of the node Nn.

  As shown in FIG. 3, the node Nn includes a control unit 11, a storage unit 12, a buffer memory 13, a decoder unit 14, a video processing unit 15, a display unit 16, an audio processing unit 17, a speaker 18, a communication unit 19, and an input. The unit 19a is provided. The control unit 11, the storage unit 12, the buffer memory 13, the decoder unit 14, the video processing unit 15, the display unit 16, the audio processing unit 17, the communication unit 19, and the input unit 19a are connected to each other via a bus 19b. Yes. As the node Nn, a personal computer, an STB (Set Top Box), a TV receiver, a karaoke device, or the like is applicable.

  The storage unit 12 is composed of, for example, a hard disk drive. The storage unit 12 stores an operating system, a P2P program, and the like. Further, the storage unit 12 stores and stores content acquired from the content holding node or the content management server MS, or a metafile of the content, and further chunks. Furthermore, content catalog information, a routing table using DHT, and the like are stored in the storage unit 12 of the node Nn participating in the overlay network ON.

  The buffer memory 13 buffers the received content or chunk. The decoder unit 14 performs decoding processing such as data expansion and decoding of video data and audio data included in the content or chunk. The video processing unit 15 performs a predetermined drawing process on the video data decoded by the decoder unit 14 and reproduces and outputs it as a video signal. The display unit 16 displays a video or the like on the display based on the video signal reproduced and output from the video processing unit 15. The display unit 16 displays the image decoded by the decoder unit 14. The audio processing unit 17 performs D (Digital) / A (Analog) conversion of the audio data decoded by the decoder unit 14 into an analog audio signal, and then amplifies this by an amplifier and outputs it. The speaker 18 outputs the sound signal output from the sound processing unit 17 as a sound wave. The communication unit 19 controls communication of information between the content management server MS and other nodes Nn through the network NW.

  The control unit 11 includes a CPU having a calculation function, a working RAM, a ROM, and the like. And the control part 11 performs the process mentioned later, when CPU reads and runs the P2P program memorize | stored in the memory | storage part 12 grade | etc.,. The control unit 11 is an example of an acquisition unit in the present invention.

[ 4. Operation of Content Distribution System S ]
Next, the operation of the content distribution system S according to the present embodiment will be described.

(4-1. Composite content input operation)
First, with reference to FIG. 4 and the like, a composite content input operation will be described. FIG. 4 is a flowchart showing composite content input processing in the control unit 1 of the content management server MS. The process shown in FIG. 4 is started, for example, when the control unit 1 acquires composite content uploaded from the content provider management terminal Tm to the content management server MS. In the composite content uploaded from the management terminal Tm, for example, a plurality of sub-content files are collected into one compressed file by archiving. The acquired composite content is stored in the storage unit 2.

  When the processing shown in FIG. 4 is started, the control unit 1 expands the acquired composite content on the RAM, and generates a sub-content list describing information on each sub-content (step S1). In the generated sub-content list, information such as accessor and file size of each sub-content is described. Here, the accessor of the subcontent is, for example, the file name of the subcontent. Further, the file size of the sub content represents the data amount of the sub content. The accessor and the file size of the subcontent are acquired from the header of the subcontent file, for example.

  Next, the control unit 1 performs sub-content chunking processing (step S2). Hereinafter, the chunking process will be described separately in the first embodiment and the second embodiment. The chunking process means a process for incorporating sub-contents into a chunk.

(Chunking processing in the first embodiment)
First, the chunking process in the first embodiment will be described with reference to FIG. FIG. 5 is a flowchart illustrating the chunking process according to the first embodiment. FIG. 6 is a flowchart showing details of the sub-content dividing process in step S222 shown in FIG.

  In FIG. 5, the control unit 1 first initializes a meta file of composite content (step S201). In this initialization, a metafile composed of a header part and a data part is generated. In the data portion of the metafile, the sub-content accessor, chunk ID, and the like are described by the following processing.

  Next, the control unit 1 selects one sub-content from the sub-content list generated in step S1 (step S202). The sub contents are selected in the order described in the sub contents list, for example. In addition, a flag indicating selection in the sub-content list is described in the selected sub-content.

  Next, the control unit 1 determines whether or not the file size of the sub-content selected in step S202 is smaller than the chunk file size threshold (step S203). The threshold used in step S203 is set in advance to, for example, several Mbytes. If the control unit 1 determines that the file size is smaller than the chunk file size threshold (step S203: YES), the control unit 1 proceeds to step S204. On the other hand, when the control unit 1 determines that it is not smaller than the threshold of the chunk file size (step S203: NO), the control unit 1 proceeds to step S205.

  In step S204, the control unit 1 describes the information of the sub content selected in step S202 in the non-division sub content list, and the process proceeds to step S206. The non-dividing sub-content list is a list for describing information on sub-contents having a file size smaller than the threshold of the chunk file size. The non-division sub-content list is generated separately from the sub-content list generated in step S1, for example. Alternatively, the non-dividing sub-content list may be provided in the sub-content list generated in step S1.

  In step S205, the control unit 1 describes the sub-content information selected in step S202 in the sub-content list for division, and proceeds to step S206. The sub-content list for division is a list for describing information of sub-contents having a file size equal to or larger than the threshold of the chunk file size. The sub-content list for division is generated separately from the sub-content list generated in step S1. Alternatively, the sub-content list for division may be provided in the sub-content list generated in step S1.

  In step S206, the control unit 1 determines whether there is any sub-content that has not yet been selected on the sub-content list. If the control unit 1 determines that there is sub-content not yet selected (step S206: YES), the control unit 1 returns to step S202. Returning to step S202, the control unit 1 selects one sub-content from the sub-contents not yet selected on the sub-content list, and performs the processing after step S203.

  On the other hand, if the control unit 1 determines that there is no sub-content not yet selected (step S206: NO), the control unit 1 proceeds to step S207.

  In step S207, the control unit 1 sorts the sub-content information described in the non-division sub-content list in a predetermined order. As an example, the control unit 1 sorts the sub-content information in descending order of file size. As another example, the control unit 1 sorts the information of the sub contents in the order of reproducing the sub contents. For example, in the composite content, the sub-content information is sorted in the order of reproduction starting from the sub-content information that is the starting point of the reproduction. Note that reproduction is an example of output.

  Next, the control unit 1 initializes the counter i to a value of “0”, and generates an empty chunk i (step S208). Here, the counter i is a variable and is incremented by one, for example. An empty chunk i is a chunk whose sub-content has not yet been incorporated in its data part.

  Next, the control unit 1 selects a sub-content from the non-dividing sub-content list based on a predetermined rule (step S209). Here, when the file size is sorted in the descending order in step S207, the “predetermined rule” is a rule for selecting sub-contents in descending order of the file size. In this case, in step S209, the control unit 1 selects, for example, one sub-content having the largest file size from among sub-contents not yet selected in the non-division sub-content list. As a result, chunking can be performed more efficiently and with simple implementation. Note that a plurality of sub contents having the largest file size may be selected.

On the other hand, when the sub-contents are sorted in the order of reproduction of the sub-contents in step S207, the “predetermined rule” is a rule for selecting the sub-contents in the order of the reproduction order . In this case, in step S209, the control unit 1 selects, for example, one of the sub-contents with the earliest playback order from the sub-contents that have not been selected in the non-dividing sub-content list. Thereby, when composite content is reproduced, sub-content can be acquired more quickly from a chunk.

  Next, the control unit 1 calculates the sum of the file sizes of all the sub contents selected in step S209 when the counter i is the latest value (step S210). Here, the counter i is incremented in step S221, but in the loop of step S209 to step S215 while step S212 continues to be “NO” and “YES” in step S215. The counter i does not change and takes the same value. The “counter i is the latest value” means the counter i in the loop at the present time. That is, in step S210, the sum of the file sizes of all the sub contents selected in step S209 in the loop when the kainta i is the latest value (for example, 10) is calculated.

  Next, the control unit 1 compares the sum of the file sizes calculated in step S210 with the threshold of the chunk file size (step S211). That is, each time a sub-content is selected in step S209, a comparison process is performed between the total file size and the chunk file size threshold.

  Next, the control unit 1 determines whether or not the sum of the file sizes is greater than the chunk file size threshold (step S212). Note that the threshold value used in steps S211 and S212 is set to be the same as the threshold value used in step S203, for example. Or you may comprise so that the threshold value used by step S211 and S212 may be set larger than the threshold value used by step S203.

  If the control unit 1 determines that the sum of the file sizes is not larger than the chunk file size threshold (step S212: NO), the control unit 1 proceeds to step S213. On the other hand, when the control unit 1 determines that the sum of the file sizes is larger than the threshold of the chunk file size (step S212: YES), the control unit 1 proceeds to step S218.

  In step S213, the control unit 1 determines the sub contents selected in the most recent step S209 as contents to be combined. That is, the control unit 1 determines sub-contents based on the comparison result in step S211 so that the sum of the file sizes calculated in step S210 is less than or equal to the chunk file size threshold. As a result, the total file size can be efficiently collected as one content so that the total is within a threshold value.

  Next, the control unit 1 incorporates the determined sub-content into the data part of the chunk i (step S214). Here, there is a case where the sub-content is already incorporated in the data part of the chunk i. In this case, the sub-content selected thereafter is connected to the sub-content already selected and incorporated. At this time, in the non-dividing sub-content list, a flag indicating selection is described in association with the information of the sub-content incorporated in the chunk i.

  Next, the control unit 1 determines whether there is any sub-content not yet selected on the non-division sub-content list (step S215). If the control unit 1 determines that there is sub-content that has not yet been selected (step S215: YES), the control unit 1 returns to step S209. Returning to step S209, the control unit 1 selects a sub-content from sub-contents that have not been selected on the sub-content list, and performs the processing after step S210. On the other hand, if the control unit 1 determines that there is no sub-content not yet selected (step S215: NO), the control unit 1 proceeds to step S216.

  In step S216, the control unit 1 assigns a unique chunk ID to the chunk i in which the sub content is incorporated. That is, the chunk ID is assigned to the chunk i in which the sub contents determined in step S213 are combined. By adding the chunk ID, the chunk ID is described in the header part of chuck i. At this time, the file size of the chunk i is also described in the header part of the chunk i. Thus, the chunk i to which the chunk ID is assigned is stored in the storage unit 2.

  Next, the control unit 1 associates the chunk ID assigned to the chunk i, the sub-content accessor embedded in the chunk i, the sub-content offset information, and the like in the data portion of the metafile generated in step S201. A description is added (step S217), and the process proceeds to step S222. Here, the offset information indicates the data position of the sub content from the beginning of the chunk i. The data position is represented by, for example, the number of bytes.

  On the other hand, in step S218, the control unit 1 assigns a unique chunk ID to the chunk i in which the sub-content is embedded, as in step S216. Thus, the chunk i to which the chunk ID is assigned is stored in the storage unit 2.

  Next, as in step S217, the control unit 1 adds to the meta file generated in step S201, the chunk ID assigned to the chunk i, the sub-content accessor incorporated in the chunk i, the sub-content offset information, and the like. Are described in association with each other (step S219).

  Next, the control unit 1 determines whether there is any sub-content that has not yet been selected on the non-division sub-content list (step S220). If the control unit 1 determines that there is sub-content not yet selected (step S220: YES), the control unit 1 proceeds to step S221. On the other hand, if the control unit 1 determines that there is no sub-content not yet selected (step S220: NO), the control unit 1 proceeds to step S222.

  In step S221, the control unit 1 increments the counter i, generates the next empty chunk i, and returns to step S209.

  On the other hand, in step S222, the control unit 1 executes the sub-content dividing process shown in FIG. In FIG. 6, the control unit 1 increments the counter i to generate an empty chunk i (step S281).

  Next, the control unit 1 selects one sub-content from the sub-content list for division (step S282). The sub contents are selected in the order described in the sub contents list, for example. In addition, a flag indicating selection in the sub-content list is described in the selected sub-content.

  Next, the control unit 1 divides the sub-content selected in step S282 for each chunk file size threshold (step S283).

  Next, the control unit 1 incorporates the divided sub-contents into the data part of the chunk i (step S284).

  Next, as in step S216, the control unit 1 assigns a unique chunk ID to the chunk i in which the sub-content is embedded (step S285). Thus, the chunk i to which the chunk ID is assigned is stored in the storage unit 2.

  Next, as in step S217, the control unit 1 adds to the meta file generated in step S201, the chunk ID assigned to the chunk i, the sub-content accessor incorporated in the chunk i, the sub-content offset information, and the like. Are described in association with each other (step S286).

  Next, the control unit 1 determines whether there is any sub-content that has not yet been incorporated in the chunk among the sub-contents divided in step S283 (step S287). If the control unit 1 determines that there is sub-content that has not yet been incorporated (step S287: YES), the control unit 1 proceeds to step S288. On the other hand, if the control unit 1 determines that there is no sub-content not yet incorporated (step S287: NO), the control unit 1 proceeds to step S289.

  In step S288, the control unit 1 increments the counter i to generate the next empty chunk i. Then, the control unit 1 returns to step S284, incorporates the sub-content not yet incorporated into the data part of the chunk i, and performs the processing from step S285 onward. In this way, all the divided sub contents are incorporated in each chunk.

  On the other hand, in step S289, the control unit 1 determines whether there is any sub-content that has not yet been selected on the sub-content list for division. If the control unit 1 determines that there is a sub-content that has not yet been selected (step S289: YES), the control unit 1 returns to step S281 and performs the processing after step S282. On the other hand, when it is determined that there is no sub-content not yet selected (step S289: NO), the control unit 1 returns to the process illustrated in FIG.

(Chunking process in the second embodiment)
Next, the chunking process according to the second embodiment will be described with reference to FIG. The second embodiment is effective when the composite content is composed of a plurality of sub-contents associated with each other in a hierarchical structure from the upper hierarchy to the lower hierarchy. Note that the highest hierarchy corresponds to the “root” in the tree structure. On the other hand, the lowest hierarchy corresponds to “leaf” in the tree structure.

  FIG. 7 is a flowchart illustrating the chunking process according to the second embodiment. FIG. 8A is a conceptual diagram showing a state in which a plurality of sub contents associated in a hierarchical structure are chunked. In the case of the second embodiment, the sub-content information described in the sub-content list generated in step S1 includes, for example, hierarchical position information indicating the position of the hierarchy in the hierarchical structure and other associated sub-contents. Link information to be shown. In FIG. 7, the processing in steps S241 to S246 is the same as the processing in steps S201 to S206 shown in FIG.

  In step S247, the control unit 1 sorts the sub-content information described in the non-division sub-content list in a predetermined order. In the case of Example 2, the control unit 1 sorts the sub-content information in order from the lower hierarchy. Note that sub-contents in the same hierarchy are sorted, for example, in the order described in the sub-content list.

  Next, the control unit 1 initializes the counter i to a value of “0”, and generates an empty chunk i (step S248).

  Next, the control unit 1 selects a sub-content from the non-dividing sub-content list based on a predetermined rule (step S249). Here, the “predetermined rule” in the second embodiment is, for example, a rule that preferentially selects sub-contents located in the lower hierarchy of the hierarchical structure. In this case, the control unit 1 selects, for example, one sub-content located in the lowest hierarchy from the sub-contents not yet selected in the non-division sub-content list. Thereby, when composite content is reproduced, sub-content can be acquired more quickly from a chunk. When there are a plurality of sub-contents positioned at the lowest hierarchy, for example, the sub-contents sorted in the non-dividing sub-content list are selected in the earlier order.

  The processing in steps S250 to S254 is the same as the processing in steps S210 to S214 shown in FIG. In step S253, in the hierarchical structure, a plurality of sub-contents associated with each other in the upper and lower hierarchical relationship are determined as sub-contents to be combined into one.

  In step S255, the control unit 1 determines whether there is another sub-content associated with the sub-content incorporated in step S254. In this determination, the link information of the sub content incorporated in step S254 is referred to. If the control unit 1 determines that there is another sub-content associated with the control unit 1 (step S255: YES), the control unit 1 proceeds to step S256. On the other hand, if the control unit 1 determines that there is no other associated sub-content (step S255: NO), the control unit 1 proceeds to step S257.

  In step S256, the control unit 1 selects, for example, one sub-content that has not yet been selected on the non-division sub-content list among the other sub-contents determined to be associated in step S255. Return to step S250. For example, in the example shown in FIG. 8A, it is assumed that the sub content Ca is the sub content incorporated in step S254. In this case, the sub-content Cb is selected as another sub-content associated with the sub-content Ca. Then, returning to step S250, for example, it is assumed that the sub-content Cb is incorporated into the chunk i in step S254 through the processing in steps S250 to S253. In this case, in step S255, the sub-content Cc is selected from the other sub-contents Cc and Cd associated with the sub-content Cb. That is, when viewed from the sub-content Cb, the sub-content Cc located in the lower hierarchy is preferentially selected. Further, returning to step S250, for example, it is assumed that the sub-content Cc is incorporated into the chunk i in step S254 through the processing in steps S250 to S253. In this case, the other sub-content associated with the sub-content Cc is the sub-content Cb. However, since the sub content Cc is already incorporated in the chunk i, the sub content Cd associated with the sub content Cc is selected in step S256. In this way, the plurality of sub contents are chunked from the lower layer to the upper layer. In the above example, when the association is determined based on the sub content Ca, Cb is preferentially selected over the sub content Cc. That is, it is configured such that sub-contents at different levels are preferentially selected. As an example different from this configuration, sub-contents in the same hierarchy may be preferentially selected. In the case of this configuration, in the example shown in FIG. 8A, it is assumed that the sub content Ca is the sub content incorporated in step S254. In this case, the sub-content Cc in the same hierarchy is preferentially selected from the sub-content Ca in the different hierarchy.

  In addition, since the process of step S257-S261 is the same as the process of step S218-S222 shown in FIG. 5, the overlapping description is abbreviate | omitted.

  Returning to the process of FIG. 4, in step S <b> 3, the control unit 1 assigns a unique content ID to the metafile generated in the chunking process. By giving the content ID, the content ID is described in the header portion of the metafile. This content ID is also the content ID of the composite content corresponding to the metafile.

FIG. 8B shows an example of sub-content information described in the data portion of the generated metafile. In the example shown in FIG. 8B, the accessor, chunk sequence, chunk ID, and offset information of each sub-content are described in association with each other. Here, the chunk sequence indicates the playback order of the sub-contents divided in the process such as the step S22 2. In the example shown in FIG. 8B, two sub contents 51 and 52 whose access child is “/mov/movie1.wmv” are obtained by dividing one sub contents. The chunk sequence of the sub content 51 is “0”. On the other hand, the chunk sequence of the sub-content 52 is “1”. Accordingly, the playback order of the sub content 51 is earlier than that of the sub content 52. The chunk sequence indicates which playback order is first when one sub-content is divided like the sub-contents 51 and 52. Therefore, the chunk sequence is “0” for sub-contents that are not divided. On the other hand, the offset information indicates the head position of each sub-content in all the connected data when a plurality of sub-contents are incorporated and connected in one chunk. The example shown in FIG. 8B shows a case where three sub contents 61 to 63 are incorporated into one chunk (chunk ID = A00163C4). In this case, the start positions of the sub contents 61 to 63 are represented by bytes. The control unit 11 can acquire each sub-content from the linked data by referring to the offset information during the sub-content reproduction process. Note that the playback order may be described through all the sub-contents described in the metafile.

  Next, the control unit 1 performs an input process for inputting the chunk generated in the chunking process and the metafile of the composite content into the content distribution system S (step S4). This input process is one of the processes for publishing the chunk assigned with the chunk ID to the overlay network ON as one content that can be acquired from the node Nn. In this input process, the control unit 1 selects a predetermined number of nodes Nn from the nodes Nn storing node information in the storage unit 2 among the nodes Nn participating in the overlay network ON. Then, the control unit 1 accesses each selected node Nn, and transmits at least one of the chunk and the metafile. In this way, the node Nn saves at least one of the received metafile and chunk in the storage unit 12. Each node Nn that stores at least one of the metafile and the chunk executes a publish process as a content holding node. This publishing process is a process for disclosing that the metafile or chunk is stored to other nodes Nn. In this publishing process, the content holding node generates a publish message. The publish message includes the content ID of the meta file of the composite content, the IP address of the content holding node, and the like. Alternatively, the publish message includes the chunk ID of the chunk and the IP address of the content holding node. Then, the content holding node transmits the generated publish message to the root node by DHT routing. The DHT routing is known in, for example, Japanese Patent Application Laid-Open No. 2007-053662, and detailed description thereof is omitted. Then, the root node that has received the publish message stores a set of the content ID of the composite content metafile and the IP address of the content holding node in the index cache area of the storage unit 12 as index information. Further, the root node that has received the publish message stores a set of the chunk ID and the IP address of the content holding node in the index cache area of the storage unit 12 as index information.

  Next, the control unit 1 generates a composite content record corresponding to the metafile and chunk input in step S4 (step S5). In the generated record, the content ID, content name, keyword, and the like of the composite content are described. In this record, an identifier indicating that the record is a composite content record may be described. In the composite content record, an accessor of the sub-content to be reproduced first may be described.

  Next, the control unit 1 additionally registers the composite content record generated in step S5 in the content catalog information (step S6).

  Next, the control unit 1 distributes the content catalog information including the composite content record registered in step S6 to the nodes Nn participating in the overlay network ON by DHT multicast (step S7). This distribution process of content catalog information is an example of a process of publishing a chunk with a chunk ID as one content that can be acquired from the node Nn to the overlay network ON. The content catalog information distributed by DHT multicast only needs to include at least the composite content record registered in step S6. The DHT multicast is known in, for example, Japanese Patent Application Laid-Open No. 2007-053662, and detailed description thereof is omitted.

  Next, the control unit 1 transmits the content ID of the composite content to the Web server configuring the content providing site (step S8). This content providing site is a Web site for providing content such as moving images. When receiving the content ID of the composite content from the content management server MS, the Web server generates a Web page describing a content tag including this content ID. This content tag also includes an identifier indicating that it is a complex content in association with the content ID. Further, the content tag may include an accessor for the sub-content to be reproduced first. Then, the Web server registers the generated Web page so as to be provided to the node Nn.

(4-2. Composite Content Playback Operation)
Next, with reference to FIG. 9, the composite content playback operation will be described. FIG. 9 is a flowchart showing a composite content reproduction process in the control unit 11 of the node Nn.

  First, for example, a node Nn receives a Web page transmitted by accessing a content providing site. The node Nn acquires a content ID and an identifier from the content tag described in the received Web page. Then, when the node Nn determines from the identifier that the acquired content ID is the content ID of the composite content, the node Nn starts the process shown in FIG. Note that the content ID of the composite content may be searched by a keyword or the like from the content catalog information stored in the node Nn.

  When the process shown in FIG. 9 is started, the control unit 11 determines whether or not a meta file of the composite content corresponding to the acquired content ID is stored in the storage unit 12 (step S11). If the control unit 11 determines that the composite content metafile is stored (step S11: YES), the control unit 11 proceeds to step S14.

  On the other hand, when it is determined that the composite content metafile is not stored (step S11: NO), the control unit 11 executes a composite content metafile acquisition process (step S12). This acquisition process is a process of acquiring a meta file of a composite content from a content holding node or the like based on the content ID of the composite content. Specifically, the control unit 11 first generates a content location inquiry message. The content location inquiry message is a message for inquiring the location of the meta file of the composite content to the root node. Further, the content location inquiry message includes the IP address and port number of the node Nn that transmits this message, and the content ID of the composite content. Then, the control unit 11 transmits the generated content location inquiry message to the root node of the composite content by DHT routing.

  The root node that has received the content location inquiry message acquires index information corresponding to the content ID included in the content location inquiry message. Then, the root node returns the acquired index information to the node Nn that is the transmission source of the content location inquiry message. The index information returned in this way includes the IP address of the content holding node that stores the meta file of the composite content. Thus, the control unit 11 of the node Nn that is the transmission source of the content location inquiry message receives the index information from the root node. Then, the control unit 11 accesses the content holding node based on the IP address of the content holding node included in the received index information. Then, the control unit 11 downloads the composite content metafile from the content holding node. By the way, there is a case where a meta file of complex content cannot be downloaded from the content holding node. In this case, a composite content metafile is downloaded from the content management server MS.

  Since the size of the composite content metafile is small, the node Nn may be configured to acquire the composite content metafile from a predetermined server such as the content management server MS. According to this configuration, the content management server MS does not need to perform the input process of inputting the composite content metafile into the content distribution system S. Alternatively, the information on the sub content constituting the composite content may be registered in a database provided in a predetermined server such as the content management server MS instead of being described in the metafile. In this case, this server returns the sub-content information to the node Nn as a response to the request including the content ID from the node Nn.

  Next, when the downloaded metafile is stored in the storage unit 12, the control unit 11 executes the publishing process described above (step S13).

  Next, the control unit 11 determines a sub-content that is a starting point of reproduction from the metafile of the composite content (step S14). For example, the sub-content in which an accessor is described at the head in the metafile is determined as the sub-content that is the starting point of reproduction. For example, in the example shown in FIG. 8B, the top accessor in the metafile is “/html/index.html”. Alternatively, there may be a case where an accessor of a sub-content that is a starting point of reproduction is described in the composite content record in the content catalog information. In this case, the sub-content that is the starting point of reproduction may be determined by the accessor described in the composite content record. Alternatively, the content tag described in the Web page may include an accessor for the sub-content that is the starting point of reproduction. In this case, the sub-content that is the starting point of reproduction may be determined by the accessor included in the content tag described in the Web page.

  Next, the control unit 11 determines the chunk ID of the chunk including the determined sub-content from the metafile of the composite content (step S15).

  Next, the control unit 11 determines whether or not the chunk corresponding to the acquired chunk ID is stored in the buffer memory 13 or the storage unit 12 (step S16). If the control unit 11 determines that the chunk is stored (step S16: YES), the control unit 11 proceeds to step S19.

  On the other hand, when determining that the chunk is not stored (step S16: NO), the control unit 11 executes a chunk acquisition process (step S17). This acquisition process is a process for acquiring a chunk from a content holding node or the like based on the chunk ID determined in step S15. The chunk acquisition process is performed in the same procedure as the metafile acquisition process. And the control part 11 downloads a chunk from a content holding node by the acquisition process of a chunk. Incidentally, there are cases where chunks cannot be downloaded from the content holding node. In this case, the chunk is downloaded from the content management server MS. The downloaded chunk is stored in the buffer memory 13.

  Next, when storing the downloaded chunk in the storage unit 12, the control unit 11 executes the publishing process described above (step S18).

  Next, the control unit 11 extracts sub-contents from the chunks stored in the buffer memory 13 (step S19). Even when a plurality of sub contents are incorporated in one chunk, the control unit 11 extracts each sub content from the chunks stored in the buffer memory 13 with reference to the offset information.

  Next, the control unit 11 performs a reproduction process of the extracted sub content (step S20). In this reproduction process, the control unit 11 performs control for outputting the extracted sub-contents from the buffer memory 13 to the decoder unit 14 to reproduce the sub-contents.

  Next, the control unit 11 determines whether there is a sub-content to be reproduced next (step S21). For example, the control unit 11 determines whether there is a sub content to be reproduced next by referring to the meta file of the composite content. For example, there is a case where a chunk sequence indicating a reproduction order through all the sub contents is described in the meta file. In this case, the control unit 11 determines whether there is a sub-content to be reproduced next based on the chunk sequence.

  Alternatively, the sub-content accessor to be reproduced next may be described in the sub-content extracted in step S19. For example, as shown in FIG. 8B, in the case of a sub-content whose access child is “/html/index.html”, the access child of the sub-content to be reproduced next is included in the tag of the HTML document. ing. In this case, the control unit 11 determines whether there is a sub content to be reproduced next based on the accessor included in the extracted sub content tag.

  If it is determined that there is a sub-content to be reproduced next (step S21: YES), the control unit 11 determines a sub-content to be reproduced next (step S22), and returns to step S15. Returning to step S15, the control unit 11 determines the chunk ID of the chunk including the sub-content determined in step S22 from the composite content metafile. And the control part 11 performs the process after step S16 similarly to the above. Here, for example, when a plurality of sub contents are included in the chunk, the control unit 11 refers to the offset information described in the meta file of the composite content in step S19, and determines the sub contents determined above. Determine the data position in the chunk. Then, the control unit 11 extracts the sub content from the chunk based on the determined data position.

  On the other hand, when it is determined that there is no sub-content to be reproduced next (step S21: NO), the control unit 11 ends the process illustrated in FIG.

  As described above, according to the above-described embodiment, sub-contents having a small file size are collected as one content, and are input to the overlay network ON and released. Therefore, even when composite content is input to the content distribution system S, the total amount of various messages such as content location inquiry messages and publish messages that fly on the overlay network ON can be suppressed. Therefore, the utilization efficiency of the network NW can be improved.

  In addition, according to the above-described embodiment, it is possible to reduce variations in the acquisition time of individual sub contents in the process in which the node Nn buffers the necessary amount of sub contents necessary for reproducing composite contents in the buffer memory 13. . Therefore, it is possible to suppress a delay in the content reproduction waiting time.

  In the above embodiment, the peer-to-peer network using DHT is applied to the overlay network ON. However, the present invention is not limited to this. For example, a system using another overlay network may be applied. As a peer-to-peer system that does not use DHT, for example, there is a hybrid peer-to-peer system.

DESCRIPTION OF SYMBOLS 1 Control part 2 Storage part 3 Communication part 4 Bus 11 Control part 12 Storage part 13 Buffer memory 14 Decoder part 15 Video | video process part 16 Display part 17 Audio | voice processing part 18 Speaker 19 Communication part 19a Input part 19b Bus MS content management server Nn node NW network ON overlay network S content distribution system

Claims (9)

Content data is stored in one or more information processing devices in an overlay network composed of a plurality of information processing devices that can communicate with each other via a network, and each information processing device has a unique identification assigned to the content data. An information processing apparatus in a distribution system configured to acquire the content data from another information processing apparatus connected to the overlay network based on information,
An acquisition means for acquiring composite content data composed of a plurality of content data;
Generating means for generating a metafile for searching content data constituting the composite content data acquired by the acquiring means;
Determining means for determining whether the data amount of each content data constituting the composite content data acquired by the acquiring means is smaller than a predetermined data amount;
Determining means for determining content data to be collected from a plurality of content data determined to be smaller than a predetermined amount of data by the determining means;
First assigning means for assigning unique identification information to chunks in which the content data determined by the determining means are combined;
The offset information of the content data determined by the determining means, the offset information indicating the data position of the content data from the head in the chunk, and the unique identification information given to the chunk by the first giving means First description means described in the metafile;
Dividing means for dividing the content data determined not to be smaller than the predetermined data amount by the determining means by the predetermined data amount;
Second assigning means for assigning unique identification information to each chunk using each content data divided by the dividing means as a chunk;
Second description means for describing reproduction order information indicating the reproduction order between the content data divided by the dividing means, and unique identification information given to the chunk by the second assigning means in the metafile;
Third assigning means for assigning unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described;
Said chunk the identification information is given by the first application means, the said chunks wherein the identification information is given by the second applying means, the metafile said identification information is given by the third applying means And publishing means for publishing to the overlay network as content data that can be acquired from other information processing devices;
An information processing apparatus comprising: Selecting means for selecting content data based on a predetermined rule from a plurality of content data constituting the composite content data;
Comparison means for comparing the total amount of the content data selected by the selection means with a preset threshold each time the content data is selected by the selection means;
Further comprising
2. The determination unit according to claim 1, wherein the determination unit determines a plurality of content data based on a comparison result by the comparison unit so that a total amount of the content data falls within a preset threshold value. The information processing apparatus described in 1.   The information processing apparatus according to claim 2, wherein the selection unit selects the content data in descending order of the data amount determined by the determination unit. Each content data constituting the composite content data is associated in the order of output,
The information processing apparatus according to claim 2, wherein the selection unit selects the content data in the output order. Each content data constituting the composite content data is related in a hierarchical structure,
The information processing apparatus according to claim 2, wherein the selection unit preferentially selects the content data located in a lower hierarchy of the hierarchical structure. Each content data constituting the composite content data is related in a hierarchical structure,
The information processing apparatus according to claim 1, wherein the determination unit determines a plurality of pieces of content data associated with each other in a hierarchical relationship in the hierarchical structure as a plurality of pieces of content data to be combined into one. Content data is stored in one or more information processing devices in an overlay network composed of a plurality of information processing devices that can communicate with each other via a network, and each information processing device has a unique identification assigned to the content data. Based on the information, a computer included in the information processing apparatus in the distribution system configured to acquire the content data from another information processing apparatus connected to the overlay network,
Obtaining composite content data composed of a plurality of content data;
Generating a metafile for searching content data constituting the acquired composite content data;
Determining whether the data amount of each content data constituting the acquired composite content data is smaller than a predetermined data amount;
Determining content data to be combined into one of a plurality of content data determined to be smaller than the predetermined data amount;
A first assigning step of assigning unique identification information to chunks in which the determined content data is combined;
The metafile includes the determined offset information of the content data, the offset information indicating the data position of the content data from the beginning in the chunk, and the unique identification information given to the chunk by the first granting step. A first description step described in
Dividing the content data determined not to be smaller than the predetermined data amount by the predetermined data amount;
A second assigning step of assigning unique identification information to each chunk using each of the divided content data as a chunk;
A second description step of describing, in the metafile, reproduction order information indicating a reproduction order between the divided pieces of content data, and unique identification information given to the chunk by the second assignment step;
A third assigning step of assigning unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described;
The chunk to which the identification information is given by the first granting step, the chunk to which the identification information is given by the second granting step, and the metafile to which the identification information is given by the third granting step And publishing to the overlay network as content data that can be acquired from another information processing device;
Information processing program to execute. Content data is stored in one or more information processing devices in an overlay network composed of a plurality of information processing devices that can communicate with each other via a network, and each information processing device has a unique identification assigned to the content data. An information processing method in a distribution system configured to acquire the content data from another information processing apparatus connected to the overlay network based on information,
Obtaining composite content data composed of a plurality of content data;
Generating a metafile for searching content data constituting the acquired composite content data;
Determining whether the data amount of each content data constituting the acquired composite content data is smaller than a predetermined data amount;
Determining content data to be combined into one of a plurality of content data determined to be smaller than the predetermined data amount;
A first assigning step of assigning unique identification information to chunks in which the determined content data is combined;
The metafile includes the determined offset information of the content data, the offset information indicating the data position of the content data from the beginning in the chunk, and the unique identification information given to the chunk by the first granting step. A first description step described in
Dividing the content data determined not to be smaller than the predetermined data amount by the predetermined data amount;
A second assigning step of assigning unique identification information to each chunk using each of the divided content data as a chunk;
A second description step of describing, in the metafile, reproduction order information indicating a reproduction order between the divided pieces of content data, and unique identification information given to the chunk by the second assignment step;
A third assigning step of assigning unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described;
The chunk to which the identification information is given by the first granting step, the chunk to which the identification information is given by the second granting step, and the metafile to which the identification information is given by the third granting step And publishing to the overlay network as content data that can be acquired from another information processing device;
An information processing method comprising: A plurality of information processing devices that can communicate with each other via a network are provided, content data is stored in one or more information processing devices, and each information processing device has other information based on unique identification information given to the content data. In a distribution system configured to acquire the content data from the information processing device,
The first information processing device
First acquisition means for acquiring composite content data composed of a plurality of content data;
Generating means for generating a metafile for searching content data constituting the composite content data acquired by the first acquiring means;
Determination means for determining whether the data amount of each content data constituting the composite content data acquired by the first acquisition means is smaller than a predetermined data amount;
Determining means for determining content data to be collected from a plurality of content data determined to be smaller than a predetermined amount of data by the determining means;
First assigning means for assigning unique identification information to chunks in which the content data determined by the determining means are combined;
The offset information of the content data determined by the determining means, the offset information indicating the data position of the content data from the head in the chunk, and the unique identification information given to the chunk by the first giving means First description means described in the metafile;
Dividing means for dividing the content data determined not to be smaller than the predetermined data amount by the determining means by the predetermined data amount;
Second assigning means for assigning unique identification information to each chunk using each content data divided by the dividing means as a chunk;
Second description means for describing reproduction order information indicating the reproduction order between the content data divided by the dividing means, and unique identification information given to the chunk by the second assigning means in the metafile;
Third assigning means for assigning unique identification information to the metafile in which the offset information, the reproduction order information, and the identification information are described;
Said chunk the identification information is given by the first application means, the said chunks wherein the identification information is given by the second applying means, the metafile said identification information is given by the third applying means And publishing means for publishing to the overlay network as content data that can be acquired from other information processing devices;
With
The second information processing device
A second acquisition means for acquiring the meta file from another information processing apparatus on the basis of the unique identification information given to the metafile,
Third acquisition means for acquiring the chunk from another information processing apparatus based on the identification information described in the metafile acquired by the second acquisition means;
Playback means for playing back the content data constituting the chunk acquired by the third acquisition means based on the offset information or playback order information described in the metafile;
A distribution system comprising:

Images