Patent Publication Number: US-2012036350-A1

Title: Information processing apparatus, information processing method, and program

Description:
BACKGROUND 
     The present disclosure relates to an information processing apparatus, an information processing method, and a program. Particularly, the present disclosure relates to an information processing apparatus, an information processing method, and a program used in a system which can prevent content from being improperly used and track sources of improperly distributed content. 
     Recently, data communication through networks such as the Internet has become widespread, and a lot of image data, music data, and the like have been widely distributed through these networks. 
     As for a lot of content such as music data, image data, and the like, creators or sellers thereof have copyright, distribution rights, and the like. Therefore, when a service provider provides content to a user from a server through the network, for example, usage control is generally performed in order to permit only users who have qualified usage rights to use the content. 
     Specifically, control processing is performed in which the content is sent as encrypted content such that the content can be decoded only with an encryption key that the user who properly purchased the content holds, for example. If such processing is performed, however, the content is disorderly distributed if the user distributes the decoded content through the network again. 
     SUMMARY 
     It is desirable to provide an information processing apparatus, an information processing method, and a program which can specify distribution sources of content which has been improperly distributed. 
     According to a first embodiment of the present disclosure, there is provided an information processing apparatus including a data processing unit which generates content to be distributed to a client; and a communication unit which sends the content generated by the data processing unit, wherein the data processing unit combines a plurality of watermarking record blocks, each of which is obtained by embedding watermarking data into a block as section data of the content, generates content in which different watermarking data sequences are set in units of distribution processing with respect to the clients, and sends the generated content to the clients through the communication unit. 
     Moreover, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may divide content without watermarking record blocks, generate a plurality of different watermarking record content in which different watermarking data is embedded in each block, and generate content in which different watermarking data sequences are set in units of distribution processing with respect to the clients by selecting different combinations of blocks from among the plural different watermarking record content items in units of the distribution processing with respect to the clients. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may set a watermarking data sequence of content to be sent to the client as a data sequence including a unique ID as an identifier corresponding to each distribution processing. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may calculate a falsification verification value with respect to the unique ID and set a watermarking data sequence of content to be sent to the client as a data sequence including the unique ID and the falsification verification value. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may calculate an error collection code with respect to combination data between the unique ID and the falsification verification value and set a watermarking data sequence of content to be sent to the client as a data sequence including the unique ID, the falsification verification value, and the error collection code. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may set each block as section data of the content as an individual stream file designated by a play item set in a playlist file as a reproduction control information file. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may provide the common playlist file to the clients to which content with differently set watermarking data sequences has been provided. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may provide to the client only a plurality of blocks constituting a part of reproduction content in the client, generate a plurality of blocks with differently set watermarking data sequences in units of distribution processing with respect to the clients, and send the generated blocks to the clients through the communication unit. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may execute processing of generating management information making a correspondence relationship between the unique ID and information for specifying the client, and recording the generated management information in a storage unit. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may analyze a watermarking data sequence included in content, obtain the unique ID, and specify a client as a content distribution destination based on the management information. 
     Furthermore, according to the embodiment of the information processing apparatus of this disclosure, the data processing unit may analyze a watermarking data sequence included in content, execute error collection processing with an error collection code included in the watermarking data sequence, and further verify the presence of falsification in a unique ID included in the watermarking data sequence based on a falsification verification value included in the watermarking data sequence. 
     According to a second embodiment of the present disclosure, there is provided an information recording medium which records therein content which are constituent data of content to be reproduced in an information processing apparatus and includes missing data parts; and a program to be applied for executing data obtaining processing for the missing data parts of the content, wherein the information processing apparatus to which the information recording medium is attached is made to execute the program to perform processing of sending user information and an identifier of the information recording medium or a content ID to a server, obtain data blocks of the missing data parts, in each of which watermarking is recorded, from the server, and generate reproduction content. 
     Furthermore, according to the embodiment of the information recording medium of this disclosure, the program includes reproduction control information for executing reproduction processing by combining content with the missing data parts and the data blocks for the missing data parts, in each of which watermarking is recorded, such that the information processing apparatus executes reproduction processing of reproduction content to which the reproduction control information is applied. 
     According to a third embodiment of the present disclosure, there is provided an information processing apparatus including a data processing unit which executes content reproduction processing, wherein the data processing unit performs content reproduction processing by combining content with missing data parts and watermarking record blocks which is data corresponding to the missing data parts and obtained from the server and performs reproduction processing by individually and sequentially reading a stream file including reproduction data of content with the missing data parts and a stream file including the watermarking record block based on reproduction section designating information for play items set in a playlist file as a reproduction control information file. 
     According to a fourth embodiment of the present disclosure, there is provided an information processing method executed in an information processing apparatus, including the steps of performing data processing by a data processing unit generating content to be distributed to clients; and communicating by a communication unit sending the content generated in the data processing, wherein the data processing includes combining a plurality of watermarking record blocks obtained by embedding watermarking data in blocks as section data of the content and generating content in which different watermarking data sequences are set in units of distribution processing with respect to the clients. 
     According to a fifth embodiment of the present disclosure, there is provided a program which causes an information processing apparatus to execute information processing including the steps of performing data processing by causing a data processing unit to generate content to be distributed to clients; and communicating by causing a communication unit to send the content generated in the data processing, wherein the data processing includes combining a plurality of watermarking record blocks obtained by embedding watermarking data in blocks as section data of the content and causing the information processing apparatus to generate content in which different watermarking data sequences are set in units of distribution processing with respect to the clients. 
     According to a sixth embodiment of the present disclosure, there is provided an information processing method executed in an information processing apparatus including the steps of performing data processing by a data processing unit executing content reproduction processing, wherein in the data processing, content reproduction processing is performed by combining content with missing data parts and watermarking record blocks which is data corresponding to the missing data parts and obtained from the server, and reproduction processing is performed by individually and sequentially reading a stream file including reproduction data of content with the missing data parts and a stream file including the watermarking record block based on reproduction section designating information for play items set in a playlist file as a reproduction control information file. 
     According to a seventh embodiment of the present disclosure, there is provided a program which causes an information processing apparatus to execute information processing including the steps of performing data processing by a data processing unit executing content reproduction processing, wherein in the data processing, content reproduction processing is performed by combining content with missing data parts and watermarking record blocks which is data corresponding to the missing data parts and obtained from the server, and reproduction processing is performed by individually and sequentially reading a stream file including reproduction data of content with the missing data parts and a stream file including the watermarking record block based on reproduction section designating information for play items set in a playlist file as a reproduction control information file. 
     The program of this disclosure is a program which can be provided to an information processing apparatus and a computer system which can execute various program codes, for example with the use of a storing medium provided in a computer readable format and a communication medium. By providing such a program in a computer readable format, the processing based on the program is realized in the information processing apparatus and the computer system. 
     Other purposes, features, and advantages of this disclosure will be apparent by the detailed description based on the embodiments and the accompanying drawings of this disclosure which will be described later. In addition, the system in this specification means a logical assembling structure including a plurality of apparatuses and is not limited to the component apparatuses in one case. 
     According to a configuration of an embodiment of this disclosure, a configuration which can examine generation sources based on improperly distributed content is provided. Specifically, blocks as segment data of content are combined with plural digital watermarking recording blocks, and content for which a different digital watermarking data sequence is set in units of distribution processing for a client are created and provided to the client. The digital watermarking data sequence of the content to be provided to the client is set so as to include a unique ID which is a unique identifier in units of distribution processing, a Message Authentication Code (MAC) for the unique ID, and an error collection code (ECC) for (unique ID+MAC). By performing such content distribution, it is possible to analyze improperly distributed content, read the digital watermarking data sequence, obtain the unique ID, and thereby to specify the distribution source when the improperly distributed content is found. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an outline of this disclosure; 
         FIG. 2  is a diagram illustrating a specific example of content provision processing in a server operated by a service provider or the like; 
         FIG. 3  is a diagram illustrating one specific example of digital watermarking recording content; 
         FIG. 4  is a diagram illustrating a specific example of digital watermarking data including a unique ID in units of distribution content; 
         FIG. 5  is a diagram illustrating a specific example of digital watermarking data including a unique ID, a MAC, and an ECC in units of distribution content; 
         FIG. 6  is a diagram illustrating a data configuration example of management information held in a storage unit of a server; 
         FIG. 7  is a diagram showing a flowchart illustrating processing sequences for content generation and provision executed in a server such as a service provider or the like; 
         FIG. 8  is a diagram showing a flowchart illustrating a source determination processing sequence executed when improperly distributed content has been found; 
         FIGS. 9A and 9B  are diagrams illustrating examples of correspondence relationships between an AV stream file and a playlist file as a reproduction control file; 
         FIG. 10  is a diagram illustrating an example of a correspondence relationship between an AV stream file and a playlist file as a reproduction control file; 
         FIG. 11  is a diagram illustrating incomplete content including missing data parts stored in a disk and a configuration example in which content is reproduced by causing a client apparatus to sequentially arrange digital watermarking recording blocks for filling missing data provided from a server; 
         FIG. 12  is a diagram illustrating examples of segment provision processing and coupling processing between a block with no digital watermarking recording and a digital watermarking recording block; 
         FIGS. 13A and 13B  are diagrams illustrating content reproduction processing with the use of a playlist file; 
         FIGS. 14A and 14B  are diagrams illustrating content reproduction processing with the use of a playlist file; 
         FIG. 15  is a diagram showing a flowchart illustrating content reproduction processing with the use of a playlist file; 
         FIG. 16  is a diagram illustrating an example of a hardware configuration of a server; and 
         FIG. 17  is a diagram illustrating an example of a hardware configuration of a client. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Hereinafter, detailed description will be made of an information processing apparatus, an information processing method, and a program according to this disclosure with reference to the accompanying drawings. In addition, the description will be made based on the following items. 
     1. Outline of This Disclosure 
     2. Specific Example of Content Provision Processing by Server 
     3. Content Generation and Provision Processing Sequence 
     4. Source Determination Processing Sequence Based on Improperly Distributed Content 
     5. Correspondence Relationship between Block Setting and Playlist File 
     6. Example of Coupling Processing between Media Recording Content and Sever Provision Content 
     7. Examples of Segment Provision Processing and Coupling Processing between Block with No Digital Watermarking Recording and Digital Watermarking Recording Block 
     8. Example of Reproduction Processing by Content Coupling in Client Apparatus 
     9. Hardware Configuration Example of Each Apparatus 
     [1. Outline of This Disclosure] 
     Hereinafter, detailed description will be made of an information processing apparatus, an information processing method, and a program according to this disclosure with reference to accompanying drawings. 
     First, description will be made of an outline of this disclosure with reference to  FIG. 1 . This disclosure is for making it possible to specifying originators of improper content distributed on the network, for example. 
     For example,  FIG. 1  shows a server  10  operated by a service provider which provides the content such as movie, music, and the like as a target of the use management. 
     For example, a client  20  such as a PC accesses a server  10 , performs a qualified content purchase procedure, and obtains content. The qualified content is obtained through a route (a) on the network shown in  FIG. 1 . 
     The user of the client  20  is permitted to reproduce the qualified purchased content under a prescribed usage restriction. Even when the distribution content is encrypted content, for example, the qualified purchaser has a key for decoding and can decode and reproduce the encrypted content by the application of the key. 
     However, the user of the client  20  may improperly provide the decoded content to other users (users of clients to  33  shown in the drawing) through the network in some cases. For example, the decoded content may be provided to large indefinite number of users through a path (b) on the network shown in  FIG. 1 . 
     Alternatively, the user of the client  20  may provide the decoded content by improperly recording the content in media such as disks and the like to create a large number of improperly copied recording media in some cases. This is shown as a disk  41  in  FIG. 1 , for example. 
     This disclosure makes it possible to specify the sources of the improper content when distribution of such improper content is found. In the case shown in  FIG. 1 , the client  20  corresponds to the source. 
     [2. Specific Example of Content Provision Processing by Server] 
     As described above, the present disclosure makes it possible to track the source of the improper content, and the configuration of the content provided by the server  10 , which provides proper content, is made to be a special configuration in order to realize this processing. 
     Referring to  FIG. 2  and subsequent drawings, description will be made of a specific example of the content provision processing by the server managed by a service provider or the like. The server creates special content which make it possible to specify a client or a user who has distributed the improper content and provides the content to each client. 
       FIG. 2  is a diagram illustrating a specific example of content provided by the server. 
     The server has (A) original content shown in  FIG. 2 . This is content such as movie content or the like, for example. 
     The server does not provide such original content as they are to each user. 
     The server creates watermarking record content (B 1 ) to (Bn) shown in  FIG. 2  in addition to (A) original content (without watermarking record content). 
     Each of (B 1 ) to (Bn) is content, in each of which different watermarking data is recorded. That is, different watermarking patterns are recorded in respective (A) original content to create the following plural watermarking record content items. 
     (B 1 ) First Watermarking (Watermark  1 ) Record Content 
     (B 2 ) Second Watermarking (Watermark  2 ) Record Content 
     (Bn) n-th Watermarking (Watermark n) Record Content 
     These plural watermarking record content items are created. 
     Furthermore, 
     (A) Original Content (Without Watermarking Record) 
     (B 1 ) First Watermarking (Watermark  1 ) Record Content 
     (B 2 ) Second Watermarking (Watermark  2 ) Record Content 
     (Bn) n-th Watermarking (Watermark n) Record Content 
     These plural content items are divided into blocks. 
     For example, the content items (A) to (Bn) are divided into blocks at the same dividing positions (t 0 , t 1 , t 2 , . . . ) such that the reproduction time period: t 0  to t 1  is allocated to the first block, t 1  to t 2  is allocated to the second block, t 2  to t 3  is allocated to the third block, . . . as shown in the drawing, for example. 
     Although the dividing positions (t 0 , t 1 , t 2 , . . . ) of each of the content items (A) to (Bn) are necessarily identical, the sizes of the blocks including the first block, the second block, the third block, . . . are not necessarily uniform. 
     Furthermore, as shown in the lower part in  FIG. 2 , the content items (A) to (Bn), which have been divided into blocks, are combined to create content to be provided to each user. 
     In the example shown in  FIG. 2 , (U 1 ) user U 1  provision content is content configured such that the block from t 0  to t 1  is (B 1 ) first watermarking record content, the block from t 1  to t 2  is (A) original content, the block from t 2  to t 3  is (B 2 ) second watermarking record content, the block from t 3  to t 4  is (Bn) n-th watermarking record content, . . . . 
     Each one block is selected from among the content blocks (A) to (Bn) in units of blocks, and the selected blocks are combined to create one user provision content item. 
     The content to be provided to a user U 2  which is a different user from the user U 1  is content configured such that the block from t 0  to t 1  is (A) original content, the block from t 1  to t 2  is (Bn) n-th watermarking record content, the block from t 2  to t 3  is (A) original content, the block from t 3  to t 4  is (B 1 ) first watermarking record content, . . . . 
     That is, the server creates and distributes content with different block combination for each provision content item. 
     In addition, the content base data is the same even if the block combination is different, only the watermarking data embedded in the content is different, and the content reproduced by the user who received the content is the same reproduction data. 
     The clients  1  and  21  receive [(U 1 ) user U 1  provision content] through the network, store the content in a medium such as a hard disk or the like, and then read the content from the hard disk to perform reproduction processing. 
     In reproducing the content, the watermarking data is a signal at a sufficiently low level to be observed, and the user U 1  can reproduce the content without noticing that the watermarking data is recorded. 
     The clients  2  and  22  receive [(U 2 ) user U 2  provision content] with a block array which is different from that in [(U 1 ) user U 1  provision content] through the network, and store the content in a medium such as a hard disk or the like. Thereafter, the clients  2  and  22  read the content from the hard disk and perform reproduction processing. The user U 2  can also reproduce the content without noticing that the watermarking data is recorded. 
     As described above, the server provides each distribution content item to each user (client) as content all of which are set to have different block combinations, 
     With reference to  FIG. 3 , description will be made of one specific example of watermarking record content. 
       FIG. 3  shows plural content items including 
     (A) original content (without watermarking record) 
     (B 1 ) first watermarking (Watermark  1 ) record content 
     (B 2 ) second watermarking (Watermark  2 ) record content 
     (Bn) n-th watermarking (Watermark n) record content as the content data used for creating content which the server provides to the client (user) in the same manner as in  FIG. 2 . 
     The watermarking (WM) record content items (B 1 ) to (Bn) are respectively set as content which records the watermarking data set so as to include 
     (B 1 ) the content in which data [ 1 ] is recorded in each block as watermarking data 
     (B 2 ) the content in which data [ 2 ] is recorded in each block as watermarking data 
     (Bn) the content in which data [n] is recorded in each block as watermarking data. 
     In addition, although various kinds of setting can be made for embedding the watermarking, the information regarding the presence of the watermarking and multiple items of data regarding the combination of watermarking data (1 to N) are recorded in one block, for example. 
     For example, bit data ( 1 ) is recorded along with the information indicating that the watermarking is present, in plural high-frequency regions included in one block (t 0  to t 1 ) of (B 1 ) first watermarking (Watermark  1 ) record content. Such data is at a level which is not observed with the naked eyes when the image is reproduced, and is the data at an extremely low level which can be detected through the watermarking detection processing. 
     In the example shown in  FIG. 3 , 
     (B 1 ) first watermarking (Watermark  1 ) record content is set such that the same watermarking data [ 1 ] is recorded in all blocks of the content, and 
     (B 2 ) second watermarking (Watermark  2 ) record content are set such that the same watermarking data [ 2 ] is recorded in all blocks of the content. 
     In the same manner, the n-th watermarking (Watermark n) record content is set such that the same watermarking data [n] is recorded in all blocks of the content. 
     The content provision server such as a server provider uses plural watermarking record content items with such setting to create content to be provided to the user. 
     The (Ux) user Ux provision content shown in  FIG. 3  includes the block selection sequence of (B 1 ), (B 2 ), (A), (B 3 ), (B 5 ), (B 4 ), . . . , and the watermarking bit sequence of the content is 1, 2, 0, 3, 5, 4, 0, . . . . 
     In addition, the original content block in which the watermarking is not recorded is regarded as [0] in this example. 
     Moreover, the setting is also applicable in which the original content block is not be used. 
     As shown in  FIG. 3 , n watermarking record content items (B 1 ) to (Bn) are watermarking record content items in which the same watermarking data [ 1 ] to [n] are recorded in all blocks. 
     It is possible to create the distribution content in which various different watermarking data sequences are set by selecting and arranging the content in units of blocks from among the combinations of n kinds of watermarking record content items (B 1 ) to (Bn) or the combinations of n kinds of watermarking record content and the original content in which the watermarking is not embedded. 
     The server creates and provides the distribution content with different block arrays, that is, different watermarking data sequences for each new content distribution. 
     The server manages a part of data of the watermarking data sequence included in the distribution content to be provided to the client (user) as a unique ID corresponding to the distribution content. 
     This unique ID is registered and held as the management information of the server. 
     Description will be made of a specific example of watermarking data including the unique ID in units of distribution content with reference to  FIG. 4 . 
       FIG. 4  shows (Ux) user Ux provision content as one user distribution content item to be provided to the user Ux, which is described above with reference to  FIG. 3 . 
     Furthermore, the drawing shows the watermarking (WM) data sequence corresponding to the block array of the content. 
     The watermarking data sequence is 1203540 . . . . 
     This watermarking data sequence includes the data such as 
     (1) a unique ID set corresponding to the distribution content, 
     (2) a falsification verification value (MAC: Message Authentication Code) with respect to the unique ID, and 
     (3) an error collection code (ECC) with respect to (the unique ID and the MAC value). 
     In addition, the data combination of (1) to (3) is repeatedly set in one distribution content item. 
     The unique ID is an ID, which is set corresponding to the distribution content, with which it is possible to specify the content. This unique ID may be an ID created by random number generation processing based on the content distribution ID, for example, or an user ID, a transaction ID, a distribution ID, a client apparatus ID, a client address, a client MAC address, or the like may be applied as shown in  FIG. 4 . Any ID is applicable as long as it is an ID with which each distribution content item can be specified. 
     The falsification verification value is a falsification verification value with respect to the unique ID, and the MAC (Message Authentication Code) is used, for example. 
     The error collection code is an error collection code (ECC: Error Collection Code) with respect to (the unique ID and the MAC value), and data such as Reed Solomon, BCH or the like is used, for example. 
     The server executing the content distribution firstly decides the unique ID corresponding to the distribution content, then calculates the MAC value corresponding to the unique ID, and further, calculates the ECC with respect to (the unique ID+MAC). 
     The watermarking data sequence which coincides with the data sequence including [the unique ID/MAC/ECC] set as the result is decided, and a block is sequentially selected from among the content described above with reference to  FIGS. 2 and 3 , that is, from among the plural content including 
     (A) original content (without watermarking record) 
     (B 1 ) first watermarking (Watermark  1 ) record content 
     (B 2 ) second watermarking (Watermark  2 ) record content 
     (Bn) n-th watermarking (Watermark n) record content, based on the decided watermarking data sequence, to create the distribution content. 
     In addition, the data sequence including [the unique ID/MAC/ECC] is repeatedly set in the content as shown in  FIG. 5 . 
     The server which distributes the content records the management information including the unique ID of the distribution content in the storage unit of the server every time the server executes the content distribution. 
       FIG. 6  shows a data configuration example of the management information held in the storage unit of the server. 
     As shown in  FIG. 6 , the management information includes information such as a unique ID corresponding to the distribution content, block configuration information, distribution content information, distribution destination information, distribution user information, and distribution date information, for example. 
     In addition, the block configuration information is the information indicating which block from among the blocks constituting the content is the unique ID recording block, the MAC recording block, or the ECC recording block. 
     The example of the management information shown in  FIG. 6  is just an example, all items of the information are not necessary, and it is also applicable to held the information other than the above information as the management information. 
     It is not necessary to set the block configuration information as the registration information corresponding to the distribution content if a block configuration with a uniform data arrangement is set and distributed without changing the data arrangement for each distribution content item. 
     However, it is necessary to make a correspondence relationship between the unique ID and the information for specifying the distribution destination for registration. 
     [3. Content Generation and Provision Processing Sequence] 
     Next, description will be made of the content generation and provision processing sequence executed by the server such as a service provider or the like with reference to the flowchart shown in  FIG. 7 . 
     The processing based on the flow shown in  FIG. 7  is executed by a data processing unit of the server. 
     First, the unique ID corresponding to the distribution content is decided in Step S 101 . The decision processing of the unique ID is executed based on an algorithm which has been decided in advance in the server. For example, it is possible to decide the ID by the random number generation processing or based on the address of the user apparatus of the distribution destination or the user ID. 
     If the decision of the unique ID is completed in Step S 101 , a falsification verification value (MAC) based on the decided unique ID is then calculated in Step S 102 . 
     If the MAC calculation is completed in Step S 102 , an error collection code (ECC) with respect to (the unique ID+MAC) is then calculated in Step S 103 . For example, the ECC data such as Reed Solomon, BCH or the like is calculated. 
     The blocks constituting the content are then decided in Step S 104  so as to set the watermarking data sequence which is the same as the data sequence of the unique ID, the MAC, and the ECC decided or calculated in Steps S 101  to S 103 . 
     That is, the user provision content is created by performing the processing of selecting and arranging the blocks with the watermarking (WM) data in accordance with the data sequence of the unique ID, the MAC, and the ECC from among the watermarking record content (or content without watermarking record). 
     Specifically, blocks are sequentially selected from the content described above with reference to  FIGS. 2 and 3 , that is, plural content items including 
     (A) original content (without watermarking record) 
     (B 1 ) first watermarking (Watermark  1 ) record content 
     (B 2 ) second watermarking (Watermark  2 ) record content 
     (Bn) n-th watermarking (Watermark n) record content to create the distribution content in which the same watermarking data sequence as the data sequence of the unique ID, the MAC, and the ECC is set. 
     Finally, the content created in Step S 104  is provided to the user, and the management information including the correspondence information between the unique ID and the distribution destination is registered in Step S 105 . For example, the management information shown in  FIG. 6  is registered. 
     [4. Source Determination Processing Sequence Based on Improperly Distributed Content] 
     Next, description will be made of the source determination processing sequence executed when improperly distributed content is found with reference to the flowchart shown in  FIG. 8 . 
     The processing based on the flow shown in  FIG. 8  is the processing executed by the data processing unit of the server of the service provider which has executed the content distribution, for example. 
     First, detection of the watermarking data of the improperly distributed data is executed, and one combination of data set [the unique ID/MAC/ECC] is obtained from among the watermarking data sequence in Step S 201 . 
     As described above with reference to  FIG. 5 , plural data sets [the unique ID/MAC/ECC] are included in the content, and one combination of the data set is obtained from among them. 
     Then, in Step S 202 , the error collection processing of (the unique ID+MAC) data is executed with the use of the error collection code (ECC) in the data set [the unique ID/MAC/ECC] obtained in Step S 201 . 
     Then, the falsification verification of the unique ID is executed with the use of the MAC in (the unique ID+MAC) data after the error collection in Step S 103 . 
     Specifically, the MAC calculation is executed based on the unique ID read from the distribution content, and determination is made regarding whether or not the calculated MAC coincides with the MAC value read from the content. 
     If the calculated MAC coincides with the MAC value, determination is made such that falsification of the unique ID has not been made and the unique ID is the correct one. 
     If the calculated MAC does not coincide with the MAC value, determination is made such that there is a possibility in that the unique ID has been falsified. In such a case, processing proceeds from Step S 204  to Step S 206 . 
     In Step S 206 , determination is made regarding whether or not the data set of [the unique ID/MAC/ECC] is included in the other parts of the content to be verified, and the processing returns to Step S 201  to repeat the verification processing from Step S 201  for unverified data set if the data set is included in the other parts. 
     As already described with reference to  FIG. 5 , plural data sets of [the unique ID/MAC/ECC] are recorded in one content item, among which the data set without falsification may be included, and the verification processing is sequentially executed while changing the data set to be verified. 
     If it is confirmed based on the MAC verification in Step S 204  that the falsification has not been made for the unique ID as the result of such processing, processing proceeds to Step S 205 . 
     In Step S 205 , the unique ID for which it has been confirmed that falsification was not made is obtained, the identical unique ID is searched for from among the unique IDs registered in the management information which is already described with reference to  FIG. 6 , and the content distribution destination information recorded corresponding to the unique ID registration entry is obtained. It is determined that the thus obtained content distribution destination is the source of the improperly distributed content. 
     In addition, if errors in the MAC verification are determined for all data sets of [the unique ID/MAC/ECC] in the content in Step S 206 , the unique ID is not obtained from the content. However, if there are multiple improperly distributed content, it is possible to sequentially obtain and verify the content, and it is possible to obtain a correct unique ID as long as the MAC verification succeeds even for one of them. 
     As described above, since the unique ID corresponding to the distribution content is recorded as watermarking according to the configuration of this disclosure, it is possible to specify which content is the original content even if the proper content is redistributed or copied content is improperly distributed, and it is possible to specify the destination to which the proper content has been provided at first, based on the management information shown in  FIG. 6 . 
     [5. Correspondence Relationship between Block Setting and Playlist File] 
     As already described with reference to  FIGS. 2 ,  3 , and the like, individual distribution content has different block configurations in the configuration of this disclosure. 
     Description will be made of one example of the content having different block configurations, that is, the correspondence relationship between the AV stream file and the playlist file as a reproduction control file, with reference to  FIGS. 9A and 9B . 
       FIG. 9A  shows the data to be provided to the user U 1 , and  FIG. 9B  shows the data to be provided to the user U 2 . 
     A set of AV stream file with a different block array is provided to each user. 
     However, the common playlist file is provided to the both users, and it is possible to reproduce the content (AV stream) with different block arrays with the use of the same playlist file. 
     (a) The block setting for the AV stream file of the data to be provided to the user U 1  shown in  FIG. 9A  is made such that the reproduction data for the time period t 0  to t 1  is (B 1 ) first watermarking record content block, the reproduction data for the time period t 1  to t 2  is (A) content block without watermarking record, and the reproduction data for the time period t 2  to t 3  is (B 2 ) second watermarking record content block. 
     On the other hand, (b) the block setting for the AV stream file of the data to be provided to the user U 2  shown in  FIG. 9B  is such that the reproduction data for the time period t 0  to t 1  is (B 2 ) second watermarking record content block, the reproduction data for the time period t 1  to t 2  is (B 1 ) first watermarking record content block, and the reproduction data for the time period t 2  to t 3  is (A) content block without watermarking record. 
     Although the reproduction data is differently set as described above, the common file name is set for all of the data to be provided to U 1  and U 2  for the AV stream file. That is, the name of the reproduction data for the time period t 0  to t 1  is AV stream file [00001.m2ts], the name of the reproduction data for the time period t 1  to t 2  is AV stream file [00002.m2ts], and the name of the reproduction data for the time period t 2  to t 3  is AV stream file [00003.m2ts]. 
     As shown in the drawing, the play items  201  to  203  as reproduction section designating information of the AV stream file (xxxxx.m2ts) are set in the playlist file. 
     In such play items, the head play item  201  has reproduction section designating information which designates the AV stream file [00001.m2ts]. 
     The second play item  202  has the reproduction section designating information which designates the AV stream file [00002.m2ts]. 
     The third play item  203  has the reproduction section designating information which designates the AV stream file [00003.m2ts]. 
     It is possible to perform reproduction with the use of the common playlist even for the content constituted by AV stream files with different block configurations. 
     That is, with respect to the corresponding blocks as the common reproduction time period of the plural content items including 
     (A) original content (without watermarking record), 
     (B 1 ) first watermarking (Watermark  1 ) record content, 
     (B 2 ) second watermarking (Watermark  2 ) record content, 
     (Bn) n-th watermarking (Watermark n) record content, as shown in  FIG. 10 , the common AV stream file name is set, and configuration is made such that the corresponding blocks are designated and reproduced by the common play item set in the playlist file. 
     With such setting, it is possible to provide the playlist file as a common file even if the block configuration of the content to be provided to each user is different. 
     [6. Example of Coupling Processing between Media Recording Content and Sever Provision Content] 
     In the aforementioned embodiment, description is made of the configuration example in which a server couples plural blocks, completes the whole reproduction content in the server, and then provides the reproduction content to the client as a user apparatus. 
     Next, description will be made of a configuration example in which the client apparatus executes the processing of sequentially arranging the incomplete content including the missing data parts recorded in the disk and the watermarking record blocks for filling the missing data parts, which is provided by the server, to execute the content reproduction, with reference to  FIG. 11 . 
     The content recording disk  301  shown in  FIG. 11  is the disk which records the content provided to the user with or without compensation. For example, the content such as movie or the like is recorded. However, the record content  310  recorded in this disk  301  has missing data blocks  311 ,  312 , . . . as shown in the drawing. That is, only the content data with skipped parts are reproduced if the content is reproduced as it is. 
     The client  350  as the user apparatus sets this disk  301  in the client apparatus  330  and connects to the server  320 . A disk ID as a disk identifier, a content ID as an identifier of the content recorded in the disk, and further, a program  318  for content generation processing by the server connection processing and the block coupling, which will be described later, are recorded in the disk  301 . In addition, a configuration is also applicable in which the disk ID and the content ID are recorded in the program  318 . 
     The client apparatus  350  executes the connection to the server based on this program  318  and provides the disk and client specification information such as the disk ID, the client ID, the user ID, and the like to the server  320 . In addition, such series of procedures are executed as processing based on the program  318 , instruction by the server connected based on the program  318 , or a provided program. 
     The server  320  determines the content recorded in the disk and the missing blocks based on the disk ID or the content ID and provides the watermarking record blocks  321 ,  322 , . . . corresponding to the missing blocks to the client apparatus  350 . 
     In addition, the watermarking record blocks  321 ,  322 , . . . are blocks in which the same watermarking data as that described in the aforementioned embodiment is recorded. That is, the data of 
     (1) the unique ID set corresponding to the distribution content, 
     (2) the falsification verification value (MAC: Message Authentication Code) with respect to the unique ID, and 
     (3) the error collection code (ECC: Error Collection Code) with respect to (the unique ID and the MAC value) is included. 
     The server  320  provides these watermarking record blocks  321 ,  322 , . . . to the client  350  and generates and records the management information including the unique ID set as the watermarking and the provision destination information (information regarding the client apparatus and the user) of the watermarking record blocks  321 ,  322 , . . . . The same management information as that described above with reference to  FIG. 6  is generated and recorded. 
     The client apparatus  350  sets the watermarking record blocks  321 ,  322 , . . . received by the server  320  to the missing data parts of the record content read from the disk  301  to create the reproduction content  360 . In addition, the program  318  for the generation processing of the reproduction content by this block coupling is recorded in the disk  301 , and the client apparatus  350  generates the reproduction content  360  based on this program  318 . In addition, a configuration is also applicable in which the generation processing of the reproduction content  360  is executed with the use of the program provided by the second server connected based on the program  318 . Moreover, the aforementioned playlist file is included in the program. 
     As a result, the reproduction content  360  is completed as shown in the drawing, and the client apparatus  350  can perform the content reproduction. 
     As described above, the unique ID, the MAC, and the ECC are recorded in the watermarking record blocks included in the reproduction content  360 . 
     Therefore, when the user improperly distributes the content, such as redistribution of the content through the network, for example, or recording and distributing the content in another medium, it is possible to specify the distribution source, that is, the client  350  or the user of the client  350  by executing the processing described above with reference to the flowchart in  FIG. 8 , based on the improperly distributed content. 
     In addition, when the content reproduction is performed in the client apparatus  350 , the record content  310  recorded in the disk  301  and the watermarking record blocks  321  and  322  are sequentially read and reproduced based on the play items within the playlist file with the use of the aforementioned playlist file, for example. 
     As the reproduction processing, the processing is applicable in which the client apparatus  350  mounts the disk  301  and connects to the server  320  to sequentially receive the necessary watermarking record blocks  321 ,  322 , . . . from the server  320  for reproduction. 
     In addition, the processing is also applicable in which the watermarking record blocks  321 ,  322 , . . . received from the server  320  are stored in the storage unit such as a hard disk or the like, the disk  301  is attached to set and reproduce a virtual file system (VFS) including both the record data of the disk and the record data of the hard disk. 
     [7. Examples of Segment Provision Processing and Coupling Processing between Block with No Digital Watermarking Recording and Digital Watermarking Recording Block] 
     Next, description will be made of examples of section provision processing and coupling processing between the block without watermarking record and the watermarking record block with reference to  FIG. 12 . 
     In this processing example, the incomplete content (the content without watermarking record) including the missing data part recorded in the disk, which is described above with reference to  FIG. 11 , is provided from the first server  510  shown in  FIG. 12  as the common content to be provided to each user. 
     On the other hand, the second server  520  shown in  FIG. 12  provides a different watermarking record block for each distribution processing as a complement bloc for the missing data part in the same manner as the content server  320  described with reference to  FIG. 11 . 
     The first server  510  which distributes the common content including the missing data part without the watermarking record may be a caching server, for example. 
     The user common provision content  511  constituted by the blocks without watermarking record, which is commonly provided to each user, is provided with or without compensation from the first server  510 , for example, to the user. In the content provision processing, it is not necessary to provide the information regarding the client or the user, and provision is made as free content, for example, that is, content which can be freely downloaded. 
     However, the user common provision content  511  includes the missing data blocks  515 ,  516 , . . . as shown in the drawing. That is, only the content data with skipped parts can be reproduced if the content is reproduced as it is. 
     Moreover, when providing the user common provision content  511 , the first server  510  provides the content ID of the provision content, and the program  518  for the server connection processing with respect to the second server  520  and the content generation processing by the block coupling, which will be described later, to the client  550 . In addition, a configuration is applicable in which the content ID is recorded in the program  518 . 
     The client  550  as the user apparatus executes the connection with respect to the second server  520  based on the program  518  and provides the content ID and the client ID corresponding to the content obtained from the first server  510  and the information for specifying the content and the client such as the user ID or the like to the server  520 . In addition, the series of procedures are executed as the processing in response to the program  518 , the instruction from the second server connected based on the program  518 , or the provided program. 
     The second server  520  determines the content and the missing blocks based on the content ID or the like received from the client  550  and provides the watermarking record blocks  521 ,  522 , . . . corresponding to the missing blocks to the client apparatus  550 . 
     In addition, the watermarking record blocks  521 ,  522 , . . . are the blocks in which the same watermarking data as that described in the aforementioned embodiment is recorded. That is, the watermarking record blocks  521 ,  522 , . . . includes the data such as 
     (1) the unique ID set corresponding to the distribution content, 
     (2) falsification verification value (MAC: Message Authentication Code) with respect to the unique ID, and 
     (3) an error collection code (ECC) with respect to (the unique ID and the MAC value) 
     The server  520  provides such watermarking record blocks  521 ,  522 , . . . to the client  550  and generates and records the management information including the unique ID set as the water marking and the provision destination information (the information regarding the client apparatus and the user) of the watermarking record blocks  521 ,  522 , . . . . The same management information as that described above with reference to  FIG. 6  is generated and recorded. 
     The client apparatus  550  sets the watermarking record blocks  521 ,  522 , . . . received from the second server  520  as the missing data parts of the content received from the first server  510  and generates the reproduction content  560 . In addition, the program for executing the generation processing of the reproduction content by the block coupling is included in the program  518  received from the first server  510 . The client apparatus  550  generates the reproduction content  560  based on this program  518 . 
     A configuration is also applicable in which the generation processing of the reproduction content  560  is executed with the use of the program provided from the second server connected based on the program  518 . 
     As a result, the reproduction content  560  is completed as shown in the drawing, and the client apparatus  550  can reproduce the content. 
     As described above, the unique ID, the MAC, and the ECC are recorded in the watermarking record block included in the reproduction content  560 . 
     Accordingly, when the user makes improper content distribution processing such as the redistribution of the content through the network, for example, or the recording and distribution of the content in another medium, it is possible to specify the distribution source, that is, the client  550  and the user of the client  550  by executing the processing, which is described above with reference to the flowchart of  FIG. 8 , based on the improper distribution content. 
     Although the first server  510  and the second server  520  are shown as different servers in the example shown in  FIG. 12 , these servers may be configured as one server. 
     For example, the second server  520  performs the following content distribution. 
     (a) The content including the missing data parts without watermarking record is provided to a large indefinite number of users as the content which can be freely downloaded without the processing such as the user confirmation or the like. 
     (b) For the watermarking record content corresponding to the missing data parts, predetermined processing such as the user confirmation or the like is performed, and the complement blocks recording different water marking data for each distribution unit are provided. 
     A configuration is also applicable in which the above processing is performed. 
     [8. Example of Reproduction Processing by Content Coupling in Client Apparatus] 
     In the example described with reference to  FIGS. 11 and 12 , the client apparatus individually obtains the following two content items (a) and (b), that is, 
     (a) the content without watermarking record (with missing data parts) 
     (b) the content with watermarking record (blocks for complementing the missing data parts) and couples these content items to execute the content reproduction. 
     The client apparatus can execute the reproduction processing with the use of the playlist file described above with reference to  FIG. 9  in this content reproduction processing. 
     The content reproduction processing with the use of the playlist file will be described with reference to the drawings from  FIG. 13 . 
       FIG. 13  shows the following two content items. 
     (a) the content without watermarking record (common data (with missing parts)) 
     (b) the content with watermarking record (distribution unit unique data (blocks for complementing missing data parts)) 
     In the processing example described with reference to  FIG. 11 , 
     (a) the content without watermarking record (common data (with missing parts)) is the data to be read from the disk  301 , and 
     (b) the content with watermarking record (distribution unit unique data (blocks for complementing missing data parts) is the data to be obtained from the server  320 . 
     On the other hand, in the processing example described with reference to  FIG. 12 , 
     (a) the content without watermarking record (common data (with missing parts)) is the data to be obtained from the first server  510 , and 
     (b) the content with watermarking record (distribution unit unique data (blocks for complementing missing data parts)) is the data to be obtained from the second server  520 . 
     As shown in  FIG. 13 , the client individually obtains the data including 
     (a) the content without watermarking record (common data (with missing parts)) 
     (b) the content with watermarking record (distribution unit unique data (blocks for complementing missing data parts)) and stores them in the storage unit such as a hard disk or the like. The file to be stored is the individual file (AV clip stream file [xxxxx.m2ts]) in units of sequential reproduction data as shown in  FIG. 13 , for example. 
     For (a) the content without watermarking record (common data (with missing parts)), the file names including 
     common first file  571 =file name: [00001.m2ts] 
     common second file  572 =file name: [00003.m2ts] 
     common third file  573 =file name: [00005.m2ts] 
     are set and stored in the hard disk of the client apparatus. 
     On the other hand, for (b) the content with watermarking record (distribution unit unique data (blocks for complementing missing data parts)), the file names including 
     unique first file  574 =file name: [00002.m2ts] 
     unique second file  575 =file name: [00004.m2ts] 
     are set and stored in the hard disk of the client apparatus. 
     The example of the processing of coupling and reproducing these files will be described with reference to  FIG. 14 .  FIG. 14  shows the same playlist file as that described above with reference to  FIG. 9 . 
     This playlist file includes the play items  581  to  585  . . . including the information for designating the reproduction of the AV clip stream file [xxxxx.m2ts]. 
     Each of the play items  581  to  585  . . . includes the information for individually designating the AV clip stream file [xxxxx.m2ts]. 
     Specifically, each play item includes the following information for designating the reproduction section. 
     (1) The play item  581  includes the information for designating the reproduction of the common first file  571 =file name: [00001.m2ts]. 
     (2) The play item  582  includes the information for designating the reproduction of the individual first file  574 =file name: [00002.m2ts]. 
     (3) The play item  583  includes the information for designating the reproduction of the common second file  572 =file name: [00003.m2ts]. 
     (4) The play item  582  includes the information for designating the reproduction of the individual second file  575 =file name: [00004.m2ts]. 
     (5) The play item  585  includes the information for designating the reproduction of the common third file  573 =file name: [00005.m2ts]. 
     The setting is made as above. 
     The client apparatus can sequentially reproduce the content set in the plural individual files by using the playlist file with the play items set as described above. 
     Although the data of (b) the content with watermarking record (distribution unit unique data (blocks for complementing missing data parts)) is different for each distribution unit and includes the combination of different blocks constituted by different watermarking data, all the client apparatus can perform the reproduction with the use of the common playlist file since the file for the same reproduction section (tx to ty) is set to have the same file name as described above with reference to  FIGS. 9A ,  9 B and  10 . 
     In addition, the playlist file may be provided to the client  350  from any one of the disk  301  and the content server  320  in the processing example described with reference to  FIG. 11 . 
     For example, setting can be made in which the playlist file is provided to the client  350  as a part of the program  318  stored in the disk  301  or in which the playlist file is recorded in the disc as a different file from the program  318  and read by the client  350 . Alternatively, another setting is also applicable in which the playlist file is provided from the content server  320  to the client  350  along with the watermarking record blocks  321 ,  322 , . . . . 
     On the other hand, the playlist file may be provided to the client  550  from any one of the first server  510  and the second server  520  in the processing example described with reference to  FIG. 12 . 
     For example, a setting is applicable in which the playlist file is provided to the client  550  as a part of the program  518  provided from the first server  510 , or in which the playlist file is provided to the client  550  as a different file from the program  518 . Alternatively, another setting is also applicable in which the playlist file is provided from the second server  520  to the client  550  along with the watermarking record blocks  521 ,  522 , . . . . 
     In any setting, the playlist file can be provided to the all clients as the common file. 
     Referring to the flowchart shown in  FIG. 15 , description will be made of the content reproduction sequence in the client. This processing is executed as the processing of the data processing unit, which executes the reproduction processing, in the client apparatus. 
     The client apparatus which executes the content reproduction processing selects the playlist file for reproduction in Step S 301 . In this playlist file selection processing, the playlist file is automatically selected in accordance with the designation of the title of the reproduction content, for example. 
     Then, the play items set in the selected playlist file are sequentially selected in Step S 302 . The play items are selected from the top of the playlist file, for example. In addition, when the user designates the reproduction start position, the play item corresponding to the designated position is selected. 
     Next, the file [xxxxx.m2ts] designated by the selected play item is obtained, and the reproduction processing is executed in Step S 303 . 
     The determination is made regarding whether or not there is a subsequent play item, in Step S 305 . If not, the determination in Step S 305  is No, and the content reproduction processing is completed. 
     If there is a subsequent play item, the determination in Step S 305  is Yes, the processing returns to Step S 302  to select the subsequent play item and continue the processing from Step S 303 . 
     By such reproduction processing with the use of the play item, it is possible to sequentially read and reproduce different AV stream files and realize data reproduction of the mixture of the common data file with no watermarking recorded and watermarking record blocks as content with individually recorded watermarking data. 
     In addition, the content reproduction processing on the side of the client includes 
     (a) a case in which the content completed on the side of the server by coupling the blocks is reproduced, and 
     (b) a case in which the content is coupled and reproduced on the side of the client as shown in  FIGS. 11 and 12 . 
     In both cases, it is possible to perform the reproduction processing with the use of the playlist file shown in  FIG. 15 . 
     When the content with no watermarking record and the watermarking record content are respectively obtained from different routes as in the example described with reference to  FIG. 11  and in the example described with reference to  FIG. 12 , such data is recorded in a dispersed manner in the hard disk. Alternatively, such data is recorded separately in the disk and the hard disk. In such cases, it is possible to perform the smooth reproduction by the reproduction processing with the use of a virtual file system (VFS) including both the recorded data in the disk and the recorded data in the hard disk and the playlist file shown in  FIG. 15 . 
     [9. Hardware Configuration Example of Each Apparatus] 
     Finally, description will be made of a hardware configuration example of each apparatus which executes the aforementioned processing, with reference to  FIGS. 16 and 17 . 
     First, description will be made of a hardware configuration example of the server which executes the content provision processing with reference to  FIG. 16 . 
     A CPU (Central Processing Unit)  601  functions as a data processing unit which executes various kinds of processing based on the program stored in a ROM (Read Only Memory)  602  or a storage unit  608 . 
     For example, the CPU  601  executes the processing of generating the watermarking record content including blocks with watermarking record which is described above in each aforementioned embodiment, the processing of generating the distribution blocks and the content in which different combinations of watermarking blocks are set in units of distribution, processing of distributing blocks and content, the processing of creating and recording the management data, and the like. The RAM (Random Access Memory)  603  appropriately stores the program and the data executed by the CPU  601 . The CPU  601 , the ROM  602 , and the RAM  603  are connected to each other through the bus  604 . 
     The CPU  601  is connected to an input output interface  605  through the bus  604 , and an input unit  606  such as various switches, a keyboard, a mouse, a microphone, and the like and an output unit  607  such as a display, a speaker, and the like are connected to the input output interface  605 . The CPU  601  executes various kinds of processing in response to the instruction input through the input unit  606  and outputs the processing result to the output unit  607 , for example. 
     The storage unit  608  connected to the input output interface  605  is a hard disk, for example, and stores the program and various kinds of data executed by the CPU  601 . The management information and the like described with reference to  FIG. 6  are also recorded, for example. 
     A communication unit  609  communicates with external apparatuses through the network such as the Internet, the local area network, or the like. 
     Next, description will be made of a hardware configuration of the client apparatus which receives the content and executes the reproduction processing and the like, with reference to  FIG. 17 . 
     The CPU (Central Processing Unit)  701  functions as a data processing unit which executes various kinds of processing based on the program stored in a ROM (Read Only Memory)  702  or a storage unit  708 . 
     For example, the CPU  701  executes the processing of communicating with the server and the processing of recording the data received from the server in the storage unit  708  (hard disk or the like), which are described in each aforementioned embodiment, and the processing of reproducing the data from the storage unit  708  (hard disk or the like). 
     The RAM (Random Access Memory)  703  appropriately stores the program and the data executed by the CPU  701 . The CPU  701 , the ROM  702 , and the RAM  703  are connected to each other through the bus  704 . 
     The CPU  701  is connected to an input output interface  705  through the bus  704 , and an input unit  706  such as various switches, a keyboard, a mouse, a microphone, and the like and an output unit  707  such as a display, a speaker, and the like are connected to the input output interface  705 . The CPU  701  executes various kinds of processing in response to the instruction input through the input unit  706  and outputs the processing result to the output unit  707 , for example. 
     The storage unit  708  connected to the input output interface  705  is a hard disk, for example, and stores the program and various kinds of data executed by the CPU  701 . A communication unit  709  communicates with external apparatuses through the network such as the Internet, the local area network, or the like. 
     A drive  710  connected to the input output interface  705  drives a removable medium  711  such as a magnetic disk, an optical disc, a magneto-optic disc, a semiconductor memory, or the like to obtain various kinds of data such as recorded content, a program, or the like. 
     The present disclosure is described in detail with reference to specific embodiments. However, it is apparent that those skilled in the art can modify and substitute the embodiments without departing from the scope of this disclosure. That is, the present disclosure is made in order to show examples, and the understanding thereof should not be limited. In order to determine the scope of this disclosure, Claims should be referred to. 
     In addition, the series of processing described in this specification can be executed in the hardware, the software, or a composite structure thereof. When the processing is executed by the software, the processing can be executed by installing a program recording a processing sequence in the memory in the computer, or by installing a program in a general computer which can execute various kinds of processing. For example, the program can be recorded in advance in a recording medium. The program can be installed in a computer from the recording medium, or received from the network such as the LAN (Local Area Network) or the Internet and installed in the incorporated recording medium such as a hard disk or the like. 
     Moreover, the various kinds of processing described in the specification may be executed not only in the time-series manner based on the order of the description but in the parallel or individual manner if necessary or depending on the processing ability of the apparatus which executes the processing. In addition, the system in this specification means a logical assembling structure including a plurality of apparatuses and is not limited to the component apparatuses in one case. 
     The present disclosure contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2010-178426 filed in the Japan Patent Office on Aug. 9, 2010, the entire content of which are hereby incorporated by reference. 
     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.