JP5353485B2 - Content data management system, management method, utilization device, and management device - Google Patents

Description

  The present invention relates to a content data management system, management method, utilization device, and management device according to a technique for verifying the identity of known digital content data and unknown digital content data.

  In recent years, the distribution and sale of content via communication networks has become widespread. Originally, authorized management content should be licensed only to authorized users, but since it can be easily copied and distributed in a personal environment by digitization, it was once illegally copied. There has been a problem that digital content data is distributed in large quantities via a wide area network such as the Internet. Such fraudulent acts interfere with businesses that provide services for a fee and have an unfavorable impact on the digital content industry.

There is an example of Patent Document 1 as a method for distinguishing between digital content data that is properly distributed and digital content data that is illegally distributed and automatically restricting the use of illegal digital content data.

  This patent document 1 discloses that regular content and illegal content are based on a difference in compression processing or the like between digital content data encoded in a specific format used in a regular service and digital content data illegally distributed. Is disclosed in a content utilization device.

  Specifically, the fingerprint calculated with respect to the regular content and the hash value are registered in the database in association with each other, and the fingerprint and hash are calculated and collated with the database when the content is used in the content utilization device. To do. As a result of this collation, if there is a fingerprint that matches the database and the hash registered in association with the fingerprint does not match the hash of the content to be used, the content is determined to be illegal. ing.

JP 2008-269032 A

  However, in the technique disclosed in the above-mentioned document 1, since the fingerprint is to extract the feature of the content, the feature portion is approximated, and the fingerprint is judged to be the same content by the fingerprint. When there are a plurality of contents, the determination cannot be performed correctly, and there is a problem in that reproduction is restricted even for legitimate contents.

  Therefore, the present invention solves the above-described problem, and when using content data, there are a plurality of similar contents in which the characteristic portions of the contents of the content data are approximated. Even so, it is an object of the present invention to provide a content data management system, management method, utilization device, and management device that can accurately determine identity and appropriately limit content reproduction.

(Content data management system and management method)
In order to solve the above-described problems, the present invention is a content data management system, which is an element extracted from digital content data based on characteristics relating to the contents of the digital content data by calculating the first function. A first function calculation unit that calculates data; a second function calculation unit that calculates digest data extracted from the digital content data based on the bit arrangement of the digital content data by calculating the second function; A database that stores element data and digest data in association with each other, and element data that is the same as or approximate to the element data extracted from the digital content data related to distribution is searched from the database, and the searched element data that is the same or approximate Check to get the associated digest data A plurality of digest data retrieved when there are a plurality of search results by the search unit and a collation unit that compares the digest data of the digital content data related to distribution with the digest data searched by the search unit A related information registering unit for registering related information for associating.

Another invention is a method of managing content data,
(1) By calculating the first function, element data extracted from the digital content data based on characteristics relating to the contents of the digital content data is calculated, and by calculating the second function, the digital content is calculated. A function calculation step for calculating digest data extracted from the data based on the bit arrangement of the digital content data;
(2) Element data that is the same as or approximate to the element data extracted from the digital content data related to distribution is searched from a database that stores element data and digest data in association with each other. A search step to obtain associated digest data;
(3) a collation step for comparing the identity of the digest data of the digital content data related to distribution with the digest data searched by the search unit;
(4) A related information registration step of registering related information for associating a plurality of searched digest data when there are a plurality of search results in the search step.

  According to these inventions, for content data to be used, a database is searched for element data (fingerprint) obtained using the first function, and a digest of the content data recorded in association with the element data is obtained. Data (hash data) is detected. The content data and the content service are identified by collating the detected digest data with the digest data obtained by using the second function for the content data to be used. At this time, when the element data are similar and a plurality of digest data are searched, the content data related to the plurality of digest data are registered in association with each other.

  As a result, according to the present invention, even if element data is erroneously detected due to different similar contents, it is compared with digest data of related content data using related information and compared with correct digest data. The possibility of doing can be increased. In addition, according to the present invention, by performing processing that reduces the amount of content data information and performing a search, different content that is considered to be potentially similar is registered as related information, and correct digest data The possibility of comparing with can be increased.

  In the above invention, a plurality of partial data is extracted from the digital content data, and the search is performed for each of the plurality of partial data, and when there are a plurality of search results, the plurality of searched digest data are partially It is preferable to register related information associated with each data. In this case, the digital content data is searched with respect to the database for each of the plurality of partial data and the digest data is collated, so that the relationship between the contents can be registered for each part of the content. For content that is partially the same as other music, such as music, a database that is correctly related can be constructed.

  According to another aspect of the present invention, there is provided a content data management system for calculating element data extracted from digital content data based on characteristics relating to the contents of the digital content data by calculating a first function. A first function calculation unit; a second function calculation unit that calculates digest data extracted from the digital content data based on the bit arrangement of the digital content data by calculating the second function; and element data and digest data And the digest data associated with the retrieved same or similar element data by searching the database for element data that is the same as or similar to the element data extracted from the digital content data related to distribution Search part to get the A verification unit that compares the digest data of the digital content data with the digest data searched by the search unit, and a control unit that controls the reproduction of the digital content data according to the comparison result of the verification unit. When there are a plurality of search results by the search unit, the unit also compares the plurality of searched digest data with the identity of the digest data of the digital content data related to distribution.

Another invention is a method of managing content data,
(1) By calculating the first function, element data extracted from the digital content data based on characteristics relating to the contents of the digital content data is calculated, and by calculating the second function, the digital content is calculated. A function calculation step for calculating digest data extracted from the data based on the bit arrangement of the digital content data;
(2) Element data that is the same as or approximate to the element data extracted from the digital content data related to distribution is searched from a database that stores element data and digest data in association with each other. A search step to obtain associated digest data;
(3) a collation step for comparing the identity of the digest data of the digital content data related to distribution with the digest data searched by the search unit;
(4) a control step for controlling the reproduction of the digital content data in accordance with the comparison result in the collation step, and in the collation step, when there are a plurality of search results in the search step, The identity of the digital content data related to distribution with the digest data is also compared.

  According to these inventions, for content data to be used, a database is searched for element data (fingerprint) obtained using the first function, and a digest of the content data recorded in association with the element data is obtained. Data (hash data) is detected. The content data and the content service are identified by collating the detected digest data with the digest data obtained by using the second function for the content data to be used. At this time, when the element data are similar and a plurality of digest data are searched, the plurality of digest data is compared with the digest data of the digital content data related to distribution.

  As a result, according to the present invention, even if element data is erroneously detected due to different similar contents, it is compared with digest data of related content data using related information and compared with correct digest data. Therefore, the reproduction of digital content data can be appropriately controlled. In addition, according to the present invention, by performing processing that reduces the amount of content data information and performing a search, different content that is considered to be potentially similar is registered as related information, and correct digest data Therefore, it is possible to appropriately control reproduction of digital content data.

  In the above invention, a plurality of partial data is extracted from the digital content data, and the search is performed for each of the plurality of partial data, and when there are a plurality of search results, the plurality of searched digest data are partially It is preferable to register related information associated with each data. In this case, a plurality of partial data can be extracted from the digital content data, the database can be searched for each partial data, and digest data can be collated, and the relevance between the contents can be registered for each part of the content. In this way, for example, a database having a correct relevance can be constructed even for content such as a medley song that is partially the same as another song.

  In the digital content data management system and method, the digital content data management apparatus and utilization apparatus according to other inventions as described below can be used.

(Device for using digital content data)
That is, the invention of the apparatus for using digital content data calculates the first function to calculate element data extracted from the digital content data related to reproduction based on characteristics relating to the contents of the digital content data by calculating the first function. A function calculation unit; a second function calculation unit that calculates digest data extracted from the digital content data related to reproduction based on the bit arrangement of the digital content data by calculating the second function; and element data; Search the element data that is the same as or approximate to the element data extracted from the digital content data related to distribution from the database that stores the digest data in association with the digest data, and the digest data associated with the searched same or approximate element data. Search part to obtain and distribution Registration of related information that correlates a plurality of searched digest data when there are multiple search results by the collation unit that compares the digest data of the digital content data with the digest data searched by the search unit And a registration requesting unit that requests.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. The probability of comparing with can be increased. In particular, according to the present invention, a pair of identification processing is performed on the content utilization device side, and the content data management device side transmits element data and digest data corresponding to the content data related to identification to the content utilization device side. As a result, the processing on the content data management device side can be reduced, and the processing of the device can be prevented from being concentrated on one point.

  Furthermore, the invention of another digital content data content utilization apparatus calculates element data extracted from the digital content data related to reproduction based on characteristics relating to the contents of the digital content data by calculating the first function. A first function calculator that calculates digest data extracted from digital content data related to reproduction based on a bit arrangement of the digital content data by calculating a second function; A transmission unit that transmits element data and digest data calculated by the first and second function calculation units to the management device, digital content data transmitted by the transmission unit, and known content data managed by the management device A receiving unit that receives the determination result regarding the identity from the management device, and the element data When there is a plurality of element data that is the same as or similar to the element data extracted from the digital content data related to distribution in the database that stores and associates the digest data with each other, the registration of related information that associates the plurality of digest data is requested. And a registration request unit.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. The probability of comparing with can be increased.

  Furthermore, the invention of another digital content data content use device includes a transmission unit that transmits digital content data related to distribution to the management device, digital content data related to distribution, and known content data managed by the management device. Elements that are the same as or similar to the element data extracted from the digital content data related to distribution in the receiving unit that receives the determination result relating to the identity of the data from the management device and the database that stores the element data and the digest data in association with each other A registration request unit that requests registration of related information that associates a plurality of pieces of digest data when there is a plurality of pieces of data, and the determination regarding identity is performed by calculating a first function, and calculating digital content data related to reproduction. Based on the characteristics of the digital content data Calculating digest data extracted from the digital content data related to reproduction based on the bit arrangement of the digital content data by calculating the second function and calculating the second function. The element data extracted from the content data is searched for element data that is the same or similar to the element data from the database, the digest data associated with the searched element data that is the same or similar is obtained, and the digest data of the digital content data related to the distribution And the searched digest data are compared with each other.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. The probability of comparing with can be increased. In particular, according to the present invention, the identification data is paired with the content data management device, and the content use device transmits the content data related to the identification to the content data management device and receives a reply of the identification result. Reproduction can be restricted, processing on the content utilization device side can be reduced, and the device can be reduced in size and weight.

  In addition, the invention of another digital content data content utilization apparatus calculates element data extracted from the digital content data related to reproduction based on characteristics relating to the contents of the digital content data by calculating the first function. A first function calculator that calculates digest data extracted from digital content data related to reproduction based on a bit arrangement of the digital content data by calculating a second function; Element data that is the same as or similar to the element data extracted from the digital content data related to the distribution is searched from the database that stores the element data and the digest data in association with each other. A search unit for obtaining digest data; A check unit for determining the identity between the digest data of the digital content data related to the data and the digest data searched by the search unit, and a control for controlling the playback of the digital content data related to the playback according to the determination result by the check unit And a section.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. Therefore, it is possible to appropriately control reproduction of digital content data. In particular, according to the present invention, a pair of identification processing is performed on the content utilization device side, and the content data management device side transmits element data and digest data corresponding to the content data related to identification to the content utilization device side. As a result, the processing on the content data management device side can be reduced, and the processing of the device can be prevented from being concentrated on one point.

  Furthermore, the invention of another digital content data content utilization apparatus calculates element data extracted from the digital content data related to reproduction based on characteristics relating to the contents of the digital content data by calculating the first function. A first function calculator that calculates digest data extracted from digital content data related to reproduction based on a bit arrangement of the digital content data by calculating a second function; Same as the transmission unit that transmits the element data and the digest data calculated by the first and second function calculation units to the management device, the digital content data related to reproduction, and the known content data managed by the alteration detection device A receiving unit for receiving a determination result related to sex from the alteration detection device, and a receiving unit A control unit that controls the reproduction of the digital content data related to the reproduction according to the received determination result, and the determination relating to the identity is performed from the database that stores the element data and the digest data in association with each other, and Search for element data that is the same as or similar to the element data extracted from the data, obtain digest data associated with the searched element data that is the same or similar, and search for the digest data of the digital content data related to distribution If there are a plurality of search results, it is also performed by comparing the identity of the searched digest data and the digest data of the digital content data related to distribution. It is characterized by that.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. Therefore, it is possible to appropriately control reproduction of digital content data.

  Furthermore, the invention of another digital content data content use device includes a transmission unit that transmits digital content data related to distribution to the management device, digital content data related to distribution, and known content data managed by the management device. A reception unit that receives a determination result related to identity from the management device, and a control unit that controls reproduction of digital content data related to reproduction according to the determination result received by the reception unit, Calculates the element data extracted based on the characteristics regarding the contents of the digital content data from the digital content data related to reproduction by calculating the first function, and reproduces by calculating the second function. Based on the digital content data bit array Digest data calculated by calculating extracted digest data, searching the database for element data that is the same as or similar to the element data extracted from the digital content data related to distribution, and associated with the searched same or similar element data The digest data of the digital content data related to the distribution is compared with the searched digest data, and if there are a plurality of search results, the plurality of searched digest data and the digital data related to the distribution are compared. It is characterized in that it is performed by comparing the identity of content data with digest data.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. Therefore, it is possible to appropriately control reproduction of digital content data. In particular, according to the present invention, the identification data is paired with the content data management device, and the content use device transmits the content data related to the identification to the content data management device and receives a reply of the identification result. Reproduction can be restricted, processing on the content utilization device side can be reduced, and the device can be reduced in size and weight.

  In the above invention, the data processing apparatus further includes a partial data extraction unit that extracts a plurality of partial data from the digital content data, the search unit performs the search for each of the plurality of partial data, and the related information registration unit includes a search result by the search unit. When there are a plurality of pieces of information, it is preferable to register related information for associating a plurality of searched digest data for each partial data. In this case, a plurality of partial data can be extracted from the digital content data, the database can be searched for each partial data, and digest data can be collated, and the relevance between the contents can be registered for each part of the content. In this way, for example, a database having a correct relevance can be constructed even for content such as a medley song that is partially the same as another song.

(Content data management device)
On the other hand, the invention of the digital content data management device calculates a first function to calculate element data extracted from the digital content data based on characteristics relating to the contents of the digital content data. And a second function calculation unit for calculating digest data extracted from the digital content data based on the bit arrangement of the digital content data by calculating the second function, and associating the element data with the digest data. A search unit that searches the stored database for element data that is the same as or similar to the element data extracted from the digital content data related to distribution, and obtains digest data associated with the searched same or similar element data; Digital content data related to distribution Related information registration for registering related information for associating a plurality of searched digest data when there are a plurality of search results by a search unit and a search unit comparing the sameness between digest data and digest data searched by the search unit And a section.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. The possibility of comparing with can be increased. In particular, according to the present invention, the identification data is paired with the content data management device, and the content use device transmits the content data related to the identification to the content data management device and receives a reply of the identification result. Reproduction can be restricted, processing on the content utilization device side can be reduced, and the device can be reduced in size and weight.

  In addition, the invention of another digital content data management device calculates element data extracted from the digital content data related to distribution based on characteristics relating to the contents of the digital content data by calculating the first function, By calculating the function of 2, a receiving unit that receives digest data extracted from digital content data related to distribution based on the bit arrangement of digital content data, and element data and digest data are stored in association with each other. A search unit that searches the database for element data that is the same as or similar to the element data extracted from the digital content data related to distribution, and obtains digest data associated with the searched element data that is the same or similar; Digital content data die A matching unit that compares the identity of the digest data with the digest data searched by the search unit, and a related information registration unit that registers related information that associates a plurality of searched digest data when there are a plurality of search results by the search unit It is characterized by providing.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. The possibility of comparing with can be increased.

  Furthermore, the invention of another digital content data management device calculates a first function to calculate element data extracted from the digital content data based on characteristics relating to the contents of the digital content data. A calculation unit, a second function calculation unit that calculates digest data extracted from the digital content data based on the bit arrangement of the digital content data by calculating the second function, element data, and digest data A retrieval unit that retrieves element data that is the same as or similar to element data extracted from digital content data related to distribution from a database that is stored in association with each other, and obtains digest data associated with the retrieved element data that is the same or similar And digital content related to distribution A comparison unit for comparing the sameness of the digest data of the data and the digest data searched by the search unit, and a control unit for controlling the reproduction of the digital content data related to the reproduction according to the determination result by the verification unit The collation unit is characterized in that, when there are a plurality of search results by the search unit, it also compares the identity of the plurality of searched digest data with the digest data of the digital content data related to distribution.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. Therefore, it is possible to appropriately control reproduction of digital content data. In particular, according to the present invention, the identification data is paired with the content data management device, and the content use device transmits the content data related to the identification to the content data management device and receives a reply of the identification result. Reproduction can be restricted, processing on the content utilization device side can be reduced, and the device can be reduced in size and weight.

  Further, the invention of another digital content data management device calculates element data extracted from the digital content data related to distribution based on characteristics relating to the contents of the digital content data by calculating the first function, By calculating the function of 2, a receiving unit that receives digest data extracted from digital content data related to distribution based on the bit arrangement of digital content data, and element data and digest data are stored in association with each other. A search unit that searches the database for element data that is the same as or similar to the element data extracted from the digital content data related to distribution, and obtains digest data associated with the searched element data that is the same or similar; Such digital content data A collation unit comprising: a collation unit that compares the identity of the digest data with the digest data retrieved by the retrieval unit; and a control unit that controls reproduction of the digital content data related to reproduction according to a determination result by the collation unit. Is characterized in that, when there are a plurality of search results by the search unit, the same is also compared between the searched digest data and the digest data of the digital content data related to distribution.

  According to such an invention, when the element data obtained by the first function are similar to each other and a plurality of digest data obtained from the second function are retrieved from the database, the content data relating to the plurality of digest data By registering them in association with each other, even if element data is mistakenly detected due to different similar contents, the relevant digest data is used to check the correct digest data using related information. Therefore, it is possible to appropriately control reproduction of digital content data.

  In the above invention, a partial data extraction unit that extracts a plurality of partial data from the digital content data is further provided, the search unit performs the search for each of the plurality of partial data, and the related information registration unit indicates that the search result by the search unit is In the case where there are a plurality of pieces, it is preferable to register related information for associating the plurality of searched digest data for each partial data. In this case, a plurality of partial data can be extracted from the digital content data, the database can be searched for each partial data, and digest data can be collated, and the relevance between the contents can be registered for each part of the content. In this way, for example, a database having a correct relevance can be constructed even for content such as a medley song that is partially the same as another song.

  As described above, according to the present invention, when content data is used, even if there are a plurality of similar contents in which the characteristic portions of the contents of the content data are approximate, It is often possible to determine the identity and properly limit the playback of the content.

It is a block diagram which shows the whole structure of the management system of the content data which concerns on 1st Embodiment. 1 is a conceptual diagram illustrating a configuration of a content data distribution apparatus according to a first embodiment. It is a block diagram which expands and shows the 1st function calculating part of the content utilization apparatus which concerns on 1st Embodiment. It is a block diagram which expands and shows the fingerprint verification part of the content utilization apparatus which concerns on 1st Embodiment. It is a flowchart figure which shows operation | movement of the content data management system which concerns on embodiment which concerns on 1st Embodiment. It is explanatory drawing which shows the calculation process of the evaluation value in the content data management system which concerns on embodiment which concerns on 1st Embodiment. It is a flowchart figure which shows operation | movement of the content data delivery apparatus which concerns on 1st Embodiment. It is a flowchart figure which shows operation | movement of the content utilization apparatus which concerns on 1st Embodiment. It is a flowchart figure which shows operation | movement of the alteration detection apparatus which concerns on 1st Embodiment. It is a block diagram which shows the whole structure of the content data management system which concerns on 2nd Embodiment. It is a conceptual diagram which shows the structure of the content data delivery apparatus and content data alteration detection apparatus which concern on 2nd Embodiment. It is explanatory drawing which shows the structure of the content data which concern on 2nd and 3rd embodiment. It is a flowchart figure which shows the operation | movement at the time of the content data registration of the content data management system which concerns on 2nd Embodiment. It is a flowchart figure which shows the operation | movement at the time of content data registration of the content data management system which concerns on the example of a change of 2nd Embodiment. It is a conceptual diagram which shows the structure of the content utilization apparatus and content data alteration detection apparatus which concern on 3rd Embodiment. It is a flowchart figure which shows the operation | movement at the time of the service identification process of the content data management system which concerns on 2nd Embodiment. It is a flowchart figure which shows the operation | movement at the time of the content data registration of the content data management system which concerns on the example of a change of 3rd Embodiment. It is a block diagram which shows the example 1 of a change of the management system of the content data which concerns on 1st-3rd embodiment. It is a block diagram which shows the example 2 of a change of the management system of the content data which concerns on 1st-3rd embodiment.

[First Embodiment]
Hereinafter, a first embodiment of a digital content data management system according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a conceptual diagram showing an overall configuration of a digital content data system according to the first embodiment. The “module” used in the description refers to a functional unit that is configured by hardware such as an apparatus or a device, software having the function, or a combination thereof, and achieves a predetermined operation. .

(Outline of the first embodiment)
In the present embodiment, as shown in FIG. 1, the digital content data management system views a content distribution apparatus 10 for providing digital content data sales / distribution services and the digital content data sold / distributed. And a content data alteration detection device 20 that verifies the validity of the content data that is about to be viewed by the content usage device 30.

  In the present embodiment, when using the distributed digital content data in the content use device 30, element data D12 obtained by executing the first function on the digital content data D2 related to use, The element data D11 of the alteration detection device 20 is compared. When the element data D12 and D11 match, the digest data D22 obtained by executing the second function on the digital content data D2 is compared with the digest data D21 of the alteration detection device 20, If they match, reproduction is permitted assuming that the distributed digital content data D2 is valid, and conversely, if the digest data D22 and D21 do not match, it is determined that the content data has been altered, and its use Limit.

  Here, as a method of restricting the use of data, the use (viewing etc.) of digital content data is prohibited, or the user is notified through the user interface provided in the content use device that the data has been modified for use. Alternatively, control may be performed such as transmitting information indicating a transmission path through which the digital content data 35 is obtained, such as download URL information, to the management service. Other data usage restriction methods include, for example, synthesizing and outputting noise to reproduced audio and video, and intermittent reproduction.

(Configuration of content distribution device)
The content distribution device 10 is a device used by a service provider who sells / distributes arbitrary managed content data D01, a verification module for registering the verification content data D02 in the alteration detection device 20, and a distribution content And a distribution module for distributing data D03. Note that the operation of each module is controlled by the control unit 120.

  The verification system module of the content distribution apparatus 10 includes a compression unit 101, an expansion unit 102, first and second function calculation units 111 and 112, and a registration unit 105. The distribution module of the content distribution apparatus 10 includes an encryption unit 103 and a distribution unit 104.

  The first function calculation unit 111 is a module that calculates element data D11 extracted from known digital content data D1 based on characteristics related to the contents of the digital content data by calculating the first function. Specifically, the first function has a characteristic of extracting an element that controls the quality of digital content data when a person views the input digital content data, and is modified so as not to impair the quality. For example, a function that outputs a value that does not change, for example, a function that calculates a value (fingerprint) based on characteristics related to the contents of digital content data such as sound or video can be employed. Note that factors that control the quality of digital content data include a change in volume and a change in frequency spectrum.

  As a method for calculating the fingerprint, various methods including a spectrum slice fingerprint, a multi-slice fingerprint, an LPC coefficient, a cepstrum coefficient, and a spectrum peak frequency component can be used. For example, linear predictive coding (LPC) analysis extracts spectral peaks in addition to spectral shapes, which are the predictable linear characteristics of signals, and cepstrum coefficients can be used in speech and many musical instruments. It is useful for characterizing a harmonic structure signal and can be used to calculate a fingerprint.

  The first function calculation unit 111 uses the same finger as the original digital data even from degraded digital data obtained by decoding compressed digital content data or digitally converting analog converted content data. The print can be calculated.

  In the present embodiment, as shown in FIG. 2, the first function calculation unit 111 includes fingerprint calculation units 111a to 111c that calculate a plurality of types of functions, and partial data that extracts a plurality of partial data from content data. And an extraction unit 121. Then, for each partial data extracted by the partial data extraction unit 121, each of the fingerprint calculation units 111a to 111c calculates a plurality of types of functions, so that the known digital content data D1 and the unknown digital content data are calculated. A plurality of types of element data D11 extracted based on characteristics relating to the contents of the digital content data are calculated from D2, and registered in the databases 210a to 210c of the alteration detection device 20.

  On the other hand, the second function calculation unit 112 is a module that calculates the digest data D21 extracted from the known digital content data D1 based on the bit arrangement of the digital content data by calculating the second function. Specifically, the second function is a function having a characteristic that the value to be output is changed when any one bit of the input digital content data is changed, for example, all the digital data A function that calculates an irreversible value (hash value) unique to the digital data can be employed without examining the contents. Also, the same value is output when data having a slight difference that occurs when the same compressed data is decoded by different decoding devices, and the same value is output when data having a further difference is input. A function that outputs a value can also be adopted.

  As a function for calculating the hash value, MD4 (MessageDigest 4) that outputs a 128-bit hash value at high speed for given data, or “collision” in which the same hash value is generated from different data. It is possible to use MD5 (Message Digest 5) that eliminates this problem, SHA (Secure Hash Algorithm) that eliminates “collision” and outputs a 160-bit hash value.

  The compression unit 101 is a module that converts the managed digital content data D01 by compression processing to generate distribution content data D03 and verification content data D02. In this compression processing, when digital content data output from the compression unit 101 and expanded by the expansion unit 102 is processed by the first function, the output value of the first function is digitally changed to the extent that the output value is not changed. It has the property of modifying content data. Here, as the compression process and the inverse process, irreversible compression / decompression widely used for compression / decompression of digital content data and the like can be used. For example, compression methods such as ISO / IEC 11172-5, ISO / IEC 13818-5, ISO / IEC 14496-5, ISO / IEC 11172-3, ISO / IEC 13818-7, ISO / IEC 14496-3, etc. You may use the thing defined by the MPEG standard or the like with the similar effect.

  On the other hand, the decompression unit 102 inversely processes (in this case, decompression processing) the verification content data D02 to the original data size by a function that performs the inverse processing of the third function, and the inversely transformed data is known. The digital content data is a module that is input to the first function calculation unit 111 and the second function calculation unit 112, and restores the input digital content data. Note that the decompression processing by the decompression unit 102 can be omitted for the data input to the second function computation unit 112. In this case, the second function computation is performed with the verification content data D02 still compressed. The digest data D21 is calculated by being input to the unit 112. The expansion processing by the expansion unit 102 and its omission can be selected and switched as appropriate.

  The registration unit 105 is a module that registers the element data D11 and the digest data D21 of the known digital content data D1 calculated by the first function calculation unit 111 and the second function calculation unit 112 in a memory or the like. In the present embodiment, the registration unit 105 includes a transmission unit 105a, and the element data D11 and the digest data D21 of the known digital content data D1 calculated from the transmission unit 105a are transmitted to the content data modification detection device 20. Send. The transmission unit 105a is a normal communication interface, transmits / receives data through a communication network such as a public telephone line or the Internet, and transmits element data D11 and digest data D21 obtained from the verification content data D02 to known element data. And it transmits to the content data alteration detection apparatus 20 as digest data.

  The encryption unit 103 is a module that encrypts the distribution content data D03 related to distribution. The encryption unit 103 can be omitted in terms of configuration or data processing. In the case of being omitted, the distribution content data D03 is directly input to the distribution unit 104 and distributed.

  The distribution unit 104 is a module that distributes the distribution content data D03 through a transmission path such as a communication network. For example, in a document system such as the World Wide Web (WWW), an HTML (HyperText Markup Language) file, an image file, and music It is a server computer that transmits information such as files or software that has its function, stores information such as HTML documents and images, and responds to requests from client software such as a Web browser through an IP network such as the Internet. This information is transmitted.

(Configuration of content data alteration detection device)
The content data alteration detection device 20 is a content data management device that is used by the alteration detection service provider and has a function of determining the identity between the known digital content data D1 and the unknown digital content data D2. Specifically, the content data alteration detection device 20 receives a determination unit 230 that is a determination module for determining the identity of digital content data, and element data D11 and digest data D21 of digital content data known from the service provider side. An anti-service system module to be acquired, and a verification object acquisition system module that acquires and transmits element data D12 and digest data D22 of unknown digital content data to be reproduced on the user side.

  The service module includes a receiving unit 201 and a database 210. The receiving unit 201 receives element data D11 and digest data D21 of known digital content data (verification content data D02) transmitted from the content distribution apparatus 10. In particular, in the present embodiment, the receiving unit 201 receives a plurality of types of element data D11 extracted based on characteristics relating to the contents of each digital content data from the digital content data D1 related to distribution.

  The database 210 stores known digital content data D1 which is “managed content data” acquired from the content distribution apparatus 10, and element data D11 and digest data D21 of each digital content data D1 in association with each other. Device. In the database 210, unique content data identification information is added to each digital content data D1, and each digital content data D1 is identified by the content data identification information. For example, a device such as a hard disk or a memory card can be employed as the database 210. The database 210 is a relational database composed of a plurality of database devices 210a to 210c. Each database device 210a to 210c has a function for each element when element data of each digital content data D1 generates element data. It is classified and stored.

  The determination unit 230, which is a determination module, cooperates with the control unit 307 and the evaluation unit 3112 on the content data utilization device 30 side in accordance with a comparison result for each of a plurality of types of functions, This is a function for determining identity with digital content data, and specifically includes first and second comparison units 233 and 234, a collation unit 231, and a search unit 232. In particular, in the present embodiment, the determination unit 230 determines whether the known digital content data D1 and the unknown digital content data D2 are in accordance with a comparison result for each of a plurality of types of functions and a comparison result for each extracted partial data. Determine the identity of.

  The search unit 232 is a module that searches the database 210 for element data D11 and digest data D21 corresponding to the known and unknown digital content data D1 and D2, respectively. In the database 210, known digital content data D1 that is “managed content data” acquired from the content distribution apparatus 10, element data D11 of each digital content data D1, and digest data D21 are stored in association with each other. By retrieving element data that is the same as or similar to the element data to be retrieved, digest data associated with the retrieved element data can be extracted.

  The first comparison unit 233 is a module that compares the identity of the element data D11 and D12 extracted from each of the known and unknown digital content data D1 and D2, and the second comparison unit 234 This module compares the sameness of digest data D21 and D22 extracted from unknown digital content data D1 and D2, respectively. The comparison results in the comparison units 233 and 234 are input to the verification unit 231. In particular, in the present embodiment, the first comparison unit 233 determines the identity of element data extracted by a plurality of types of functions from each of the digital content data D2 related to reproduction and the digital content data D1 related to distribution. Compare for each kind of function.

  The collation unit 231 of the determination unit 230 cooperates with the control unit 307 and the evaluation unit 3112 on the content data utilization device 30 side in accordance with the comparison results of the first and second comparison units 233 and 234, respectively. This module determines the identity between content data D1 and unknown digital content data D2. In particular, the collation unit 231 has a function of calculating the degree of identity between element data to be compared as reliability information reliability. In the present embodiment, comparison by the first and second comparison units 233 and 234 and calculation of reliability information reliability are performed on the alteration detection device 20 side, and final determination processing and usage control processing based on these are performed in the content This is performed on the use device 30 side. The determination unit 230 plays a role of coordinating with the control unit 307 of the content use device 30 by counting the processes on the modification detection device 20 side and notifying the content use device 30 side.

  This identity determination will be described in detail. In the present embodiment, the first comparison unit 233 compares the element data D12 obtained by the content use device 30 with the element data D11 of the alteration detection device 20. When the element data D12 and D11 coincide with each other, the second comparison unit 234 further compares the digest data D22 obtained by the content using device 30 with the digest data D21 of the alteration detection device 20. The comparison result is transmitted from the collation unit 231 to the evaluation unit 3112 of the content using device 30 as a determination result D3 including content data identification information for specifying the compared content data and reliability information reliability.

  The evaluation unit 3112 is content data in which the content data is managed by adding weighting information weight regarding each partial data to the content data identification information and reliability information reliability that are the comparison results by the first comparison unit 233. Whether or not the first stage is determined. Thereafter, the control unit 307 uses the hash value to make a second-stage determination as to whether or not the content maintains identity.

  In the determination at the second stage, when the comparison in the second comparison unit 234 matches, the digital content data D2 related to use is valid (identity with the managed content data is maintained). On the other hand, if the digest data D22 and D21 do not match, it is determined that the content data has been altered (the identity of the managed content data is not maintained). The control unit 307 executes or restricts playback of the content data D2 related to playback according to the determination result.

  In the present embodiment, the identity of content data is determined by the cooperation of the alteration detection device 20 and the content utilization device 30, but the comparison processing and comparison by the first and second comparison units 233 and 234 described above. The identification process based on the result and the reliability information reliability may be performed by only one of the alteration detection device 20 and the content use device 30.

  As the verification target acquisition system module, the receiving unit 213 that receives the unknown element data D12 and the unknown digest data D22 extracted from the unknown digital content data D2, and the determination data D3 that is the determination result are sent to the content use device 30. A transmission unit 214 for transmission is provided. In particular, in the present embodiment, the receiving unit 213 receives a plurality of types of element data extracted based on characteristics relating to the contents of each digital content data from the digital content data D1 related to reproduction.

(Configuration of content utilization device)
The content utilization device 30 is a player device that plays back and outputs data so that the user can view the content data. The content utilization device 30 downloads digital content data through a communication network, a recording unit such as a CD-ROM or a memory card. It is possible to acquire content data through the external input unit 302 which is a medium reading device. Specifically, the content use device 30 includes a verification system module including a first function calculation unit 311, a second function calculation unit 312, a partial data extraction unit 321, and the like, and a playback system module that acquires and plays back content data. Have.

  The verification module includes a transmission unit 305 and a reception unit 306 in addition to the partial data extraction unit 321, the usage-side first function calculation unit 311 and the usage-side second function calculation unit 312.

  The partial data extraction unit 321 is a module that extracts a plurality of partial data from the content data. Each partial data extracted by the partial data extraction unit 321 is input to the first function calculation unit 311 and the second function calculation unit 312. Is done.

  The first function computing unit 311 computes element data D12 extracted from unknown digital content data D2 related to reproduction based on characteristics related to the contents of the digital content data by computing the first function. It is. Specifically, the first function has a characteristic of extracting an element that controls the quality of digital content data when a person views the input digital content data, and is modified so as not to impair the quality. For example, a function that outputs a value that does not change, for example, a function that calculates a value (fingerprint) based on characteristics related to the contents of digital content data such as sound or video can be employed. Note that factors that control the quality of digital content data include a change in volume and a change in frequency spectrum.

  In particular, in the present embodiment, as shown in FIG. 3A, the first function calculation unit 311 includes fingerprint verification units 311a to 311c that calculate a plurality of types of functions and verify a plurality of types of element data. In the identification process, the fingerprint verification units 311a to 311c ... perform fingerprint verification using a plurality of types of functions for each of the plurality of partial data.

  As shown in FIG. 3B, each of the fingerprint verification units 311a to 311c... Calculates a fingerprint data calculation unit 3111 that calculates element data using a first function, and calculates weighting information for each partial data. The evaluation unit 3112 for calculating the evaluation value is provided.

  The fingerprint calculation unit 3111 is a module that calculates element data using functions assigned to the fingerprint verification units 311a to 311c. The evaluation unit 3112 calculates weighting information weight for the partial data extracted by the partial data extraction unit 321 and acquires content data identification information and reliability information reliability from the determination data D3 returned from the collation unit 231 for each partial data. In this module, the most probable content data identification information is selected from the input information. The control unit 307 performs usage control (reproduction permission or reproduction restriction) based on the content data identification information selected by the evaluation unit 3112. In the present embodiment, when the evaluation value is calculated by the evaluation unit 3112, the above-described weighting information weight and reliability information reliability are included as parameters, but the evaluation value is omitted by including one or both of these parameters. May be calculated.

  On the other hand, the second function calculation unit 312 is a module that calculates the digest data D22 extracted from the unknown digital content data D2 based on the bit arrangement of the digital content data by calculating the second function. Specifically, the second function is a function having a characteristic that the value to be output is changed when any one bit of the input digital content data is changed, for example, all the digital data A function that calculates an irreversible value (hash value) unique to the digital data can be employed without examining the contents. Also, the same value is output when data having a slight difference that occurs when the same compressed data is decoded by different decoding devices, and the same value is output when data having a further difference is input. A function that outputs a value can also be adopted.

  The transmission unit 305 is a module that transmits element data D12 and digest data D22 of unknown digital content data D2 that is about to be reproduced on the user side to the content data modification detection device 20 on the modification detection service provider side. The reception unit 306 receives the determination result regarding the identity of the element data D12 and the digest data D22 of the unknown digital content data D2, the element data D11 managed by the modification detection service provider, and the digest data D21, and the content data modification detection apparatus 20 is received.

  In the reproduction system module, a storage device 310 that stores digital content data received by the reception unit 301 or input from the external input unit 302, a decoding unit 303 and a decompression unit 304 that decrypts / decompresses the digital content data, And an output unit 308.

  As the storage device 310, for example, a device such as a hard disk or a memory card can be employed. The data stored in the storage device 310 may be “managed content data” acquired from the content distribution device 10, acquired from other distribution services, or “unmanaged content” created by the user himself / herself. Data "is included. Therefore, when digital content data is read from the storage device 310 during reproduction, it is unknown whether the content data is managed or not, and is verified as unknown digital content data. It becomes the object of.

  The decryption unit 303 is a module for decrypting the content data read from the storage device 310 if it is encrypted, and the decrypted data is input to the decompression unit 304. In addition, when the encryption unit 103 is omitted in the configuration or data processing, the decryption unit 303 can be omitted in the configuration or data processing. When the decryption unit 303 is omitted, the content data related to reproduction is input to the decompression unit 304 as it is.

  The decompression unit 304 is a unit that decompresses in accordance with the compression method on the content distribution apparatus 10 side. The decompressed data is the first function calculation unit 311 and the second function as unknown digital content data D2 to be verified. The data is input to the calculation unit 312 and input to the reproduction output unit 308 as reproduction data.

  Here, it is desirable that the processing performed by the decryption unit 303 and the decompression unit 304 is inseparably implemented, for example, constituted by a single chip so that separation is difficult, so that the decryption unit 303 can It is possible to prevent the compressed data from flowing out after being decrypted.

  A transmission unit 305 is connected to the first function calculation unit 311 and the second function calculation unit 312, and element data D12 and digest data D22 that are processing results of the first function calculation unit 311 and the second function calculation unit 312 are connected. Is transmitted to the verification object acquisition system module of the content data alteration detection device 20.

  The reproduction output unit 308 is a module that outputs audio data from an output device such as a speaker if the content data is music data, and outputs video data from an output device such as a display if the content data is video. In the present embodiment, the playback output unit 308 is connected to a control unit 307 that controls playback of unknown digital content data D2 related to playback according to the determination result in the content data alteration detection device 20.

  The control unit 307 is an arithmetic processing device that executes content data identification processing. The control unit 307 is connected to the reception unit 306, and can receive the determination data D3 returned from the content data alteration detection device 20 through the communication network. Yes. In addition, an evaluation unit 3112 is connected to the control unit 307. The weighting information weight calculated by the evaluation unit 3112 and the content from the determination data D3 returned from the collation unit 231 of the determination unit 230 for each partial data. Data identification information and reliability information reliability are acquired, and the most probable content data identification information is calculated from these input information. The control unit 307 performs data use restriction based on the content data identification information calculated by the evaluation unit 3112.

  Here, as a method of restricting the use of data, the use (viewing etc.) of digital content data is prohibited, or the user is notified through the user interface provided in the content use device that the data has been modified for use. Alternatively, control may be performed such as transmitting information indicating a transmission path through which the digital content data 35 is obtained, such as download URL information, to the management service. Other data usage restriction methods include, for example, synthesizing and outputting noise to reproduced audio and video, and intermittent reproduction.

(Identification process)
Next, with reference to FIGS. 3A and 3B, the identification processing related to the first function in the content use device 30 and the modification detection device 20 described above will be described in detail. Here, in the identification processing, partial data and element data thereof are extracted on the content use device 30 side, compared with the managed content data on the modification detection device 20 side, and determination using the comparison result is performed. A case will be described as an example where content use restriction is performed in cooperation with the content use device 30 and the modification detection device 20.

  Further, in the identification processing according to the present embodiment, the content data is managed by adding weighting information weight related to each partial data to content data identification information and reliability information reliability that are search / comparison results regarding element data. A first stage determination is made as to whether or not the contents data, and then a second stage determination is made as to whether or not the contents maintain the identity using the digest data (hash value). .

  In the figure, content data related to reproduction is input as unknown digital content data D2 to a partial data extraction unit 321 and partial data 3 having a size larger than the minimum data amount necessary for fingerprint detection is extracted. . In the extraction of the partial data 3, for example, the offset position at which the extraction is started may be set while being sequentially shifted from the head at a constant interval, or the one with high weighting information calculated by the evaluation unit 322 is selected with priority. May be.

  Next, it is evaluated whether or not the extracted partial data is a part of content data suitable for identification in the evaluation unit 207a. In this evaluation method, depending on the fingerprint algorithm, weighting information is generated by evaluating the degree of time that the power above a predetermined threshold continues over time and the degree to which the frequency spectrum is flat. . If this weighting information is high, for example, it is uniform in the time axis direction, and variation occurs in the frequency axis direction, so that the values of 1 and 0 of the obtained fingerprints are distributed evenly and discontinuously. Thus, the content data part is suitable for identification.

  Next, in the first function calculation unit 311, a plurality of types of element data that are fingerprints based on different algorithms are generated from each partial data by a plurality of types of functions. The converted element data is transmitted to the determination unit 230 of the alteration detection device 20, and the element data is sequentially read from the database 210 by the search unit 232 and compared by the first comparison unit 233. In the comparison performed by the first comparison unit 233, when approximate element data is detected, the collation unit 231 of the determination unit 230 collates the database 210 and sets content data identification information for identifying the corresponding element data. And obtain reliability information reliability indicating how likely the fingerprint verification is. When reliability information reliability is not accumulated on the database 210, it may be evaluated as a certain reliability.

  The content data identification information and the reliability information reliability obtained in this manner are returned as determination data D3 from the collation unit 231 of the determination unit 230 to the evaluation unit 3112 of the content utilization device 30.

  Next, an operation of content data identification processing in the present embodiment will be described. FIG. 4A is a flowchart specifically showing the operation of content data identification processing.

  In the figure, when content data identification is started, partial data is extracted from the content data by the partial data extraction unit 321 (S101), and the partial data is a part of the content data suitable for identification by the evaluation unit 3112. It is evaluated whether or not (S102). For the evaluation of this part, the entire content data is evaluated, how much the value of each partial data is deviated from this overall evaluation, and weighting for each partial data is performed from the deviation rate. The evaluation result regarding each partial data is set as weighting information weight.

  Next, each fingerprint calculation unit 3111 calculates element data (fingerprint) by using different algorithm functions F (1) to F (3) for each partial data (S103), and n different values are obtained. E (1), E (2), ..., E (n) corresponding to the element data and E (0), which is the evaluation value when content data identification information cannot be obtained, are initialized to 0 (S104). Next, each element data is transmitted to the modification device 20 side, and the database 210 of the modification detection device 20 is retrieved for each different function by the search unit 232, the first comparison unit 233, and the collation unit 231 of the determination unit 230. Compare and collate (S105).

  More specifically, when similar element data is detected by searching the database 210 (S105: Y), the collation unit 231 determines how much content data identification information and fingerprint collation for specifying the content data are. Reliability information reliability indicating whether it is certain is calculated. This reliability information is calculated for each content data including the detected approximate element data, and is returned to the evaluation unit 3112 of the content using device 30 with E (1 to m) corresponding to each content data identification information as an index. Is done. At this time, the evaluation unit 3112 corresponding to the type of the function that generated the element data is selected and returned. On the other hand, when the approximate element data is not detected, reliability information reliability with E (0) as an index is returned to the corresponding evaluation unit 3112.

  For example, as shown in FIG. 4B, when content data 1 to 3 including element data approximate to partial data 1 is detected, reliability information with E (1) to E (3) as indexes is given. In the other partial data 2, when content data 1, 2 and 4 are detected, reliability information with E (1), E (2) and E (4) as indexes is given. If approximate element data is not detected, reliability information with E (0) as an index is returned.

  Each time the E (m) appears in each evaluation unit 3112 on the side of the content distribution apparatus 10 that has received such a reply of reliability information, the value obtained by multiplying the weight by the reliability is index E (m) ( 0 <m <= n) is added every time (S107), and if there is next partial data, the above-mentioned database collation is repeated (S108: Y). On the other hand, as a result of the collation in step S105, when the approximate element data is not detected and the corresponding content data identification information is not obtained (S105: N), the process proceeds to step S106, and the weight value is set to E (0 ) And the process proceeds to step S108.

  If the processing of all partial data is completed in step S108 (S108: N), the process proceeds to step S109, and the calculated evaluation values E (1), E (2),. The largest value is searched (S109), and the maximum value is set as Emax. Next, when the value obtained by subtracting E (0) from Emax is larger than the predetermined threshold (S110: Y), the process proceeds to step S111, and the content data identification information corresponding to Emax is determined to be true content data identification information. To do. On the other hand, if the value obtained by subtracting E (0) from Emax is less than the predetermined threshold value (S110: N), the process proceeds to step S112, and it is determined that the content data identification has failed. In the above processing, reliability is assumed to change with a value between 0.0 and 1.0 as an example of how to set, for example, in fingerprint verification, it is set to 1.0 when the fingerprint registered in the database completely matches, When there are many partial mismatches of the fingerprints and approximates a threshold value for determining a match, the value can be set to about 0.5.

  In addition, as an example of setting the weight value, an evaluation value obtained by determining whether or not the partial data continues at a level equal to or higher than the average output level of the content data for a certain period of time and a partial data obtained by time-frequency conversion are obtained. The result obtained by multiplying both the evaluation values obtained by determining the flatness of the frequency spectrum can be used as a weight value, and a value of 0.0 to 1.0 is taken.

  Then, the first stage determination is performed based on the content data identification information determined by the element data identification process. Here, when the identification is successful, it is determined as managed content data. On the other hand, when the identification fails, it is determined as unmanaged content data.

  Next, the control unit 307 compares the digest data according to the identification result related to the element data, and performs the second stage determination based on the comparison result. Here, if the digest data matches, it is determined that the content data is managed content data and the identity is maintained. On the other hand, if the digest data do not match, it is determined that the content data is managed, but is not altered and maintained identical.

(Digital content data management method)
By operating the digital content data management system including the above identification processing, the digital content data management method according to the present embodiment can be implemented. 5A to 5C are flowcharts showing the operation of the digital content data management system according to this embodiment.

  First, as shown in FIG. 5A, the content distribution apparatus 10 compresses the managed content data D01 to generate distribution content data D03 and verification content data D02 (S1201). The distribution content data D03 is encrypted by the encryption unit 103 and then distributed to the content use device 30 by the distribution unit 104 (S1202 and S1203). Note that the encryption unit 103 can be omitted in terms of configuration or data processing, and thus step S1202 is also executed or omitted as necessary. When this step S1202 is omitted, the distribution content data D03 is directly input to the distribution unit 104 and distributed in step S1203.

  On the other hand, the verification content data D02 is expanded by the expansion unit 102 (S1204), and is input to the first function calculation unit 111 and the second function calculation unit 112. In the first function calculation unit 111, the partial data extraction unit 121 generates a plurality of partial data, executes a plurality of types of first functions for each partial data, and the verification content data D02 includes a fingerprint or the like. Element data D11 is calculated. The second function calculation unit 112 executes the second function, calculates the digest data D21 such as a hash value for each of the verification content data D02 (S1205 and 1206), and sends them to the content data modification from the transmission unit 105a. It transmits to the detection apparatus 20 (S1207).

  On the other hand, as shown in FIG. 5B, the content using device 30 downloads (receives) the distribution content data D03 by the receiving unit 301 and stores it (S1301). At the same time, the content use device 30 can acquire content data from a recording medium such as a CD-ROM or a memory card through the external input unit 302.

  Then, the reproduction of the content data is started according to the user operation (S1302). At the time when the digital content data is read from the storage device 310 at the time of reproduction, it is unknown whether the content data is managed or not, and as unknown digital content data D2, Decoded and decompressed (S1303). The expanded data is input to the first function calculation unit 311 and the second function calculation unit 312 as unknown digital content data D2, and is also input to the reproduction output unit 308 as reproduction data. Note that the encryption by the encryption unit 103 in step S1202 can be omitted in terms of configuration or data processing, and thus the decryption by the decryption unit 303 in step S1303 can be omitted as well. . When this step S1303 is omitted, the content data related to reproduction is input to the decompression unit 304 as it is and decompressed.

  In the first function calculation unit 311 and the second function calculation unit 312, element data D12 and digest data D22 are generated by the first function and the second function (S1304 and S1305), and element data D12 that is the result of this processing is generated. The digest data D22 is transmitted to the verification object acquisition system module of the content data alteration detection device 20 through the transmission unit 305 (S1306).

  On the other hand, the content data alteration detection device 20 acquires the managed digital content data received from the content distribution device 10 as shown in FIG. 5C (S1401). Here, the content distribution apparatus 10 receives the element data D11 and the digest data D21 extracted from the managed digital content data D1, and stores them in the storage apparatus 210. In parallel with this, the content data modification detection device 20 acquires unknown digital content data from the content utilization device 30 (S1402). Here, the element data D12 and the digest data D22 extracted from the unknown digital content data D2 are received on the content utilization device 30 side.

  Then, identification processing is performed on the element data (S1403). Specifically, in the content data alteration detection device 20, the element data D11 and D12 are compared by the first comparison unit 233, and based on the comparison result, the collation unit 231 performs the first stage determination ( S1404). In the determination at the first stage, the processes of steps S101 to S112 described above are performed. In step S1404, if the element data D11 and D12 do not match, it is determined that the identification has failed, and the unknown digital content data D2 is determined as content data whose management state is unknown (S1409). On the other hand, if the element data D11 and D12 match, it is determined that the element data has been successfully identified, and the process proceeds to step S1405.

  In step S1405, the digest data D21 and D22 are read out and compared and collated by the second comparison unit 234 and the collation unit 231 (S1405 and S1406). Then, the collation unit 231 transmits the above-described first stage determination result together with the comparison result in the second comparison unit 234 to the control unit 307 of the content utilization device 30. This determination result is transmitted as determination data D3 from the transmission unit 214 to the content using apparatus 30 (S1408 to S1410). The final identification process is performed on the content utilization device 30 side based on the determination data D3.

  In step S1404, if the modification detection device 20 matches the element data and the identification is successful (S1404: Y), the content data identifier acquired in step S1405 is set as an index E (1 to m), and the digest is used. Reliability information reliability is calculated according to the degree of coincidence of data, and is returned to the content using apparatus 30 side as determination data D3 (steps S1408 and S1410). On the other hand, if the element data do not match and identification fails (S1404: N), E (0) and its reliability information reliability are returned to the content using apparatus 30 side (step S1409).

  Next, the second stage determination is performed. This determination in the second stage is processing including comparison / collation of digest data. In this embodiment, the content data alteration detection device 20 performs comparison / collation processing (S1407) and uses the comparison / collation result. The final determination is made by the control unit 307 of the content use apparatus 30. Specifically, as shown in FIG. 5B, if the digest data D21 and D22 match, the unknown digital content data D2 is managed content data and the identity is maintained. (S1309: Y). On the other hand, if the digest data D21 and D22 do not match, it is determined that the content data is managed but has not been altered and maintained identical (S1309: N).

  In accordance with this determination result, whether or not playback / output is possible in the playback output unit 308 is controlled in the content use device 30. That is, content data that is not managed (S1308: Y) or content data that maintains the identity (S1308: Y) based on the comparison result in the first comparison unit 233 and the comparison result in the second comparison unit 234. If it is S1309: Y), the reproduction is permitted (S1311). If the identity is not maintained (S1309: N), the reproduction is restricted (S1310).

(Operational effects of this embodiment)
As described above, according to the digital content data management system and management method according to the present embodiment, a plurality of types of functions are calculated in determining the identity between known digital content data and unknown digital content data. Since multiple types of elemental data obtained in the above are compared, it is possible to compare digital content data with different standards and methods, and prevent erroneous determination from other similar digital content data. High identification can be performed.

  In the present embodiment, in determining the identity between known digital content data and unknown digital content data, partial data of segmented content data is extracted, and element data is compared for each partial data. Digital content data can be compared in more detail, and it can be prevented from being erroneously determined as other similar digital content data, and identification with high accuracy can be performed.

  Furthermore, in this embodiment, when comparing element data, reliability information indicating the degree of identity is calculated, the identity is evaluated by taking the reliability information into account, and digital content data is identified. Therefore, regular digital content data can be determined in more detail, and erroneous determination can be reduced.

[Second Embodiment]
(Configuration of digital content data management system)
Next, a second embodiment of the present invention will be described. In the second embodiment, a related information registration unit 400 is added to the system described in the first embodiment, and content data that are likely to be erroneously determined are registered in association with each other. 6 and 7 are block diagrams showing the content data management system according to the present embodiment. In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and the functions and the like are the same unless otherwise specified, and the description thereof is omitted.

  As shown in the figure, in the above management system, a related information registration unit 400 is installed so that it can be accessed from the collation unit 231 of the alteration detection device 20, and the related information obtained as a result of collation by the collation unit 231 is displayed as a collation unit. 231 to the database 210 through the related information registration unit 400. This related information is information related to content data similar to the content data. Specifically, when a plurality of approximate element data are detected when identifying certain element data, the related element data is included in the retrieved element data. This is data that associates corresponding digest data as hash information and related hash information.

  The content distribution apparatus 10 is provided with a related information detection unit 115 that registers related information in the related information registration unit 400 when registering regular content data related to distribution in the database.

  When the digest information (hash value) of other content data including a fingerprint that is similar to the element data (fingerprint) of the content data related to distribution is searched, the related information detection unit 115 retrieves the digest data from each other. This is a module that causes the related information registration unit 400 to register related information for association. Specifically, the related information detection unit 115 includes a processing unit 115a, a partial data extraction unit 115b, and a first function calculation unit 115c.

  The processing unit 115a is a module that performs processing for reducing the information amount of the content data and is input to the first function calculation unit 115c through the partial data extraction unit 115b. Examples of processing in the processing unit 115a include processing using downsampling, a low-pass filter, and the like, and this processing processing may be performed by adjusting the reduction amount or not at all as necessary. . The processing unit 115a performs various processing on one content data, generates a large number of fingerprints corresponding to the content data variously changed by the processing, and retrieves digest data that approximates each fingerprint. 232 to retrieve related information.

  As shown in FIG. 8, the partial data extraction unit 115b is a module that extracts a plurality of partial data that is a part of digital content data. Each partial data extracted by the partial data extraction unit 115b is input to the first function calculation unit 115c. In the extraction of the partial data, for example, the offset position at which the extraction is started is set while being sequentially shifted from the head at a constant interval.

  The first function calculation unit 115c is a module that generates a fingerprint using the same algorithm as the first function calculation unit 111d. When the first function calculation unit generates a plurality of types of fingerprints using a plurality of types of functions, Fingerprints are generated by functions corresponding to various functions, and a search is performed for each fingerprint.

  The collation unit 231 also retrieves element data (fingerprints) in normal search processing, and associates the related data registration unit 400 with the digest data (hash value) corresponding to the retrieved element data. The other hash values are also verified. As a result, when there are a plurality of search results in the search unit 232, the collation unit 231 has the same digest data (hash information and related hash information) as the digest data of unknown digital content data related to reproduction. The sex will be compared.

(Content data management method)
By operating the content data management system having the above configuration, the content data management method according to the present embodiment can be implemented. FIG. 9 is a flowchart showing an operation at the time of content data registration of the content data management system according to the present embodiment. Here, a case where regular content data (managed content data D01) related to the content data distribution service is registered in the database 210 of the alteration detection device 20 will be described as an example.

  First, in the content distribution apparatus 10, when the registration process is started, the verification content data D02 is copied from the managed content data D01, and the first function calculation unit 111, the second function calculation unit 112, and the related information detection unit are copied. Input to 115. Then, the first function calculation unit 111 calculates the element data D11 for the entire content data D02, and as shown in FIG. 9, the second function calculation unit 112 calculates the digest data D21 for the entire content data D02. (S201). In parallel with these processes, the processing unit 115a performs content data processing (S202).

  Next, partial data is extracted from the processed content data (S203), and element data is sequentially calculated by the first function for the extracted partial data (S204, S205). A database is searched using the fingerprint calculated for each partial data (S206). If there is no finger printer to be searched in this database search (S207: N), the process proceeds to step S203 to perform the next partial extraction.

  If element data is detected in step S207 (S207: Y), digest data associated with the detected element data is read and registered in the database 210 as related information of the hash value calculated in step S201, or The registration in step S208 is reserved. This registration is stored in one of the selected databases 210a to 210c according to the function for which the element data is generated.

  More specifically, in step S206, the search unit 232 of the alteration detection apparatus 20 searches the database 210 using the processed element data D31, and element data (fingerprint) that matches the element data D31 on the database 210. Is present, the digest data registered in association with the retrieved element data is output to the collation unit 231 as the hash value D41.

  In the collation unit 231, when the hash value D41 does not match the digest data D21 that is the normal hash value, it is assumed that there is duplicate digest data, and the related information registration unit 400 determines that the digest data D22 and the hash value D41 are Register or make a registration reservation in the database 210 in association with each other. When there are a plurality of hash values D41, all hash values D41 are similarly registered in the database 210 as hash values related to the digest data D22. Then, it progresses to step S203 and the next partial extraction is performed.

  In step S204, when extraction of all partial data is completed (S204: Y), the process proceeds to step S209, and element data D11 is calculated from the entire content data before being processed in step S202. Then, the element data D11 from the entire content data and the digest data D22 calculated in step S201 are registered in association with each other (S210). At this time, if there is related information reserved in the related information registration unit 400, it is registered together.

Here, service identification information including fingerprints, hash values, and related information registered in the database 210 is shown in Table 1.

  In the table, the first column indicates fingerprint data, the second column indicates a hash value, and the third column indicates related hash information. The same row is information related to the same content data. Fl1, FI2,... Fln are fingerprint sets of content data composed of m fingerprints of the first content data, and Hl is a hash value calculated from the entire first content data. F2m, F22,..., F2m are fingerprint sets of content data composed of m fingerprints of the second content data, and H2 is a hash value calculated from the entire second content data. F31, F32,... F3k are fingerprint sets of content data composed of k pieces of fingerprints of the third content data, and H3 is a hash value calculated from the entire third content data. Here, any one of Fl1, Fl2,..., Fln coincides with any of F21, F22,... F2m, and coincides with any of F32,. Assume that the content data and the third content data are related, and the related hash information is H2 and H3 for H1, H1 and H3 for H2, and H1 and H2 for H3. sign up.

(Example of change)
In the second embodiment, the digest data registered in the database 210 is a hash value for the entire content data. However, in this modification, partial data is extracted from the content data, and a hash value is obtained for each partial data. sign up. Table 2 shows service identification information including fingerprints, hash values, and hash-related information registered in the database in this modification.

  In the table, the first column indicates fingerprint data, the second column indicates a hash value, and the third column indicates related hash information. The same line is information related to the same part of the same content data. F11 is a fingerprint of the first part of the first content data, and H11 is a hash value calculated from the first part of the first content data. Fl2 is a fingerprint of the second part of the first content data, and H12 is a hash value calculated from the second part of the first content data. F21 is a fingerprint of the first part of the second content data, and H21 is a hash value calculated from the first part of the second content data. F32 is a fingerprint of the second part of the third content data, and H32 is a hash value calculated from the second part of the third content data.

  Here, when F11 matches F21 and F12 matches F32, the first part of the first content data is similar to the first part of the second content data, and the first content data The second part is similar to the second part of the third content data, and as related information, H21 for H11, H32 for H12, H11 for H21, H12 is registered for H32.

  In this way, by registering the relevance for each part of the content data, it is possible to avoid that different music pieces are registered as linked music pieces via a combination of a plurality of music pieces such as a medley. For example, as illustrated in FIG. 8, when there is content data 3 including a portion 1 similar to the portion 3 of the content data 1 and a portion 2 similar to the portion 4 of the content data 2, the content data is transmitted via the content data 3. It can be avoided that 1 and content data 2 are registered as related content data.

  FIG. 10 shows a flowchart of registration processing in this modification example. As shown in the figure, when registration processing is started in the content distribution apparatus 10, first, content data processing is performed (S301). The processing content described above can be used for the processing content, and no processing is required.

  Next, element data of the processed content data is extracted (S302), and a fingerprint is calculated from the extracted element data (S303, S304). In step S305, a hash value is calculated for the partial data cut out from the content data before being processed in step S301, based on the cut-out position at the time of extraction in step S304, and step S304. The database is searched using the fingerprint calculated in (S306).

  Next, if the fingerprint is not detected (S307: N), the process proceeds to step S302, and the next partial extraction is performed. If the fingerprint is detected in step S307, the process proceeds to step S308 and is related to the detected fingerprint. The detected hash information is registered in the database 210 as the hash information related to the hash value calculated in step S305 or the registration in step S308 is reserved, and the process proceeds to step S302 to perform the next partial extraction.

  If all the partial extractions of the content data are completed (S303: Y), the process proceeds to step S309, and the fingerprint is calculated from the entire content data before being processed in step S301. Next, the calculated fingerprint, all the hash values calculated in step S305 and the related hash information obtained in step S308 are associated with each other and registered in the database (S310), and the registration process is terminated.

(Operations and effects in this embodiment)
According to this embodiment and the modification, when registering content data from the content distribution device 10 to the alteration detection device 20, different similar content is obtained by associating and registering content data with similar element data. Even when element data is erroneously detected by data, it is possible to increase the possibility of comparing with digest data of related content data using related information and comparing with the correct digest data. In addition, according to the present embodiment, by performing processing that reduces the amount of content data information and performing a search, different contents that are considered to be potentially similar are registered as related information, and a correct digest is obtained. Allows comparison with data.

[Third Embodiment]
(Configuration of content data management system)
Next, a third embodiment of the present invention will be described. The third embodiment is characterized in that the related information registration function described in the second embodiment is provided on the content utilization device 30 side. FIG. 11 is a block diagram showing the relationship between the content use device 30 and the alteration detection device 20 according to the present embodiment. In the present embodiment, the same components as those in the first and second embodiments described above are denoted by the same reference numerals, and the functions and the like are the same unless otherwise specified, and the description thereof is omitted.

  As shown in the figure, in the management system, a related information registration unit 400 is installed so that it can be accessed from the collation unit 231 of the alteration detection device 20, and the collation result in the collation unit 231 is registered in the related information registration unit 400.

  Further, when content data related to playback is played back, the content using device 30 detects related information, which is information related to content data similar to the content data, and has different content data that approximates the fingerprint information. In this case, identification processing is also performed on the approximate content data.

  Also, in the present embodiment, when content data related to playback is played back, related information related to the content data is detected, and if there are a plurality of digest data (hash values), the content associated with the digest data A registration request unit 307a for registering the hash value of data in the related information registration unit 400 as related information is also provided. This registration request unit 307a is provided in the control unit 307, and when there are a plurality of search results by the search unit 232 of the alteration detection device 20, a module that requests registration of related information that associates a plurality of digest data as search results. It is. The collation unit 231 of the alteration detection device 20 requests the related information registration unit 400 to register related information in response to a request from the registration request unit 307a, and the related information registration unit 400 is related to the database 210 by this request. Register information.

  The related information registration function associates and registers digest data (hash value) of other content data including a fingerprint that is similar to the element data (fingerprint) of the content data related to distribution.

(Content data management method)
The flowchart of 3rd Embodiment is shown in FIG. In the figure, when the content use device 30 reproduces the distribution content data D03 obtained from the regular content data distribution service or other routes, the content use device 30 performs a service identification process on the distribution content data D03.

  In this service identification process, first, a hash value of content data is calculated (S401), and then partial data is extracted from the content data (S402).

  In addition to the calculation of the hash value, the content data is input to the first function calculation unit 311 to obtain element data D12 (S404). The element data D12 can be used in the same manner as in the conventional example, and the element data D12 is calculated as partial data from a part of the content data as shown as a fingerprint for searching the database 210.

  Prior to this reproduction process, there is a case where the content data processing unit 313 performs processing to reduce the amount of information of the content data D03. In this case, a fingerprint or hash value is set for the processed content data. You may make it obtain.

  Then, the search unit searches the database 210 using the fingerprint data (S406). If there is a fingerprint that matches the fingerprint data (S407: Y), the fingerprint is registered in relation to the searched fingerprint. Read the hash value D41. Next, the process proceeds to step S408, and the hash information detected in association with the detected fingerprint is reserved in the database as related hash information of the hash value calculated in step S401 (S408), and the process proceeds to S401. Partial extraction is performed.

  When the collation unit 231 has a hash value that matches the digest data D22 or matches the hash value D41 registered in relation to the hash value, the use of the content data 34 is permitted as the regular content data. Perform the process.

  In step S407, if there is no finger printer to be searched (S407: N), the process proceeds to step S402 to perform the next partial extraction.

  At this time, for the hash value that does not match the hash value D22 in the collation unit 231, it is determined that there is an illegal content or a duplicate fingerprint, and the related information registration unit 400 determines the hash value D41 and the hash value D22. Registration is reserved in the database 210 as related information to be associated (S408). If there are a plurality of hash values D41, registration of all the hash values D41 is similarly reserved in the database 210 as hash values related to the digest data D22 (S408).

  In step S403, if all the partial extractions of the content data have been completed (S403: Y), the process proceeds to step S409 and shifts to related information registration (S409).

  In step S409, either the digest data (hash) detected in association with the fingerprint or the related hash information registered in association with the detected digest data matches the hash value calculated in step S401. If so, it is determined that there are duplicate fingerprints, the registration reserved in step S408 is executed, and the related information is registered. Subsequently, the process proceeds to step S410 and shifts to use permission / use restriction (S410).

  In this step S410, the hash information detected in relation to the fingerprint in step S408 and any of the related hash information registered in relation to the detected hash information match the hash value calculated in step S401. If not, it is determined that illegal content data is used. If it is illegal content data, a process for restricting the use of the content data is performed, and the service identification process is terminated. On the other hand, in step S410, the hash information detected in association with the fingerprint in step S408 and any of the related hash information registered in association with the detected hash information match the hash value calculated in step S401. When it is done, the use is permitted assuming that the content data is regular.

(Example of change)
In the third embodiment, the digest data registered in the database 210 is a hash value for the entire content data. However, in this modification, partial data is extracted from the content data, and the hash value for each partial data is extracted. Register. In this modification, service identification information including fingerprints, hash values, and hash-related information registered in the database is as shown in Table 2.

  FIG. 13 shows a flowchart of the service identification process in this modified example. As shown in the figure, when the content data is played back in the content utilization device 30, the service identification process is started, the content data portion is extracted (S501, S502), and the fingerprint is extracted from the extracted content data. Is calculated (S503).

  In addition to this, a hash value is calculated for the data cut out from the content data based on the cut-out position at the time of extraction in step S501 (S504), and then the fingerprint calculated in step S503 The database is searched using (S505, S506), and if there is no fingerprint to be searched (S506: N), the process proceeds to step S501, the next partial extraction is performed, and if the search is performed (S506: Y), the step In step S507, the detected hash value D41 is reserved in the database as related information of the hash value calculated in step S505 (S507), and the next partial extraction is performed in step S501.

  If all the partial extractions of the content data have been completed (S502: Y), the process proceeds to step S508, where the hash information detected in association with the fingerprint in step S506 is related to the detected hash information. If any of the registered related hash information matches one of the hash values calculated in step S504, the registration reserved in step S507 is executed.

  In step S509, the hash information detected in association with the fingerprint in step S506, the associated hash information registered in association with the detected hash information, and the hash value calculated in step S504 are displayed. If either of them does not match, the use of illegal content data is determined, a process for restricting the use of the content data is performed, and the service identification process is terminated. On the other hand, in step S509, the hash information detected in association with the fingerprint in step S506 and any of the related hash information registered in association with the detected hash information match the hash value calculated in step S504. When it is done, the use is permitted assuming that the content data is regular.

  In each of the above embodiments and modifications, the case where the collation of the service identification information is performed by the content using apparatus as described above has been described. However, the collation of the service identification information is limited to the execution by the content using apparatus. For example, it can be performed by a management apparatus connected via a network. In this case, it can be realized by transmitting the content data to be used by the content using device to the management device and causing the management device to perform a service identification information collation process.

  In addition, a part of the service identification information collation process, for example, fingerprint calculation and hash value calculation may be performed by the content use apparatus, and the other process may be performed by the management apparatus.

  Furthermore, the method of registering the fingerprint, hash value information, and related hash value information in association with each other in the database is not limited to the method of registering them in direct association, but content data identification information such as content data ID and metadata May be related to each other. That is, the fingerprint and the hash value may be registered in association with the content data identification information, respectively, and the hash value information and the related hash value information are registered by associating the content data identification information with the related content data identification information. May be associated.

  The fingerprint detection method and the database may be combined with a plurality of fingerprint detection methods and databases.

(Operations and effects in this embodiment)
According to the present embodiment and the modification, content data is identified by searching and collating element data (fingerprint) and digest data (hash data) with respect to content data that is a usage target in the content usage device 30. The use of unauthorized content data can be restricted. At this time, when the element data are similar and a plurality of digest data are searched, by registering the content data related to the plurality of digest data in association with each other, the element data is mistaken for different similar content data. Even if it is detected, it is possible to increase the possibility of comparing with the digest data of the related content data using the related information and comparing it with the correct digest data. In addition, according to the present embodiment, processing is performed to reduce the amount of content data by using related information, and correct digest data is obtained even in different content data that is considered to be potentially similar. The probability of comparing with can be increased.

[Modification 1]
In the first to third embodiments described above, the first function calculation unit 311 and the second function calculation unit 312 for digital content data related to reproduction are provided on the content usage device 30 side, but as shown in FIG. In addition, these may be provided on the content data alteration detection device 20 side.

  Specifically, as shown in the figure, the first function calculation unit 311 and the second function calculation unit 312 are arranged between the reception unit 213 and the determination unit 230 in the content data modification detection device 20, The unknown digital content data D2 received by the reception unit 213 is acquired by the first function calculation unit 311 and the second function calculation unit 312, and the element data D12 calculated by the first function calculation unit 311 is used as the first comparison unit. The digest data D22 calculated by the second function calculation unit 312 is output to the second comparison unit 234.

  The transmission unit 305 on the content utilization device 30 side directly transmits the unknown digital content data D2 that is about to be reproduced on the user side to the content data alteration detection device 20. The content data alteration detection device 20 receives the unknown digital content data D2, and the first function calculation unit 311 and the second function calculation unit 312 generate element data and digest data.

  In FIG. 2, a database 210 is a recording unit that can be accessed from the person (service provider) who distributes the digital content data through the receiving unit 201. In this database 210, element data D11 obtained by executing the first function on the distribution source digital content data, and digest data D21 obtained by executing the second function on the distribution source digital content data. Is recorded.

  The first function calculator 311 calculates element data D12 from the distributed digital content data, and the function calculator 312 that executes the second function calculates digest data D22. Next, the element data D11 read from the database 210 and the element data D12 are compared in the first comparison unit 233, and when it is detected that they match, the digest data read from the database 210 is still received. The second comparison unit 234 compares D21 and the digest data D22.

  Further, in the second comparison, when it is detected that they do not match, it is determined that the distributed digital content data has been altered from the distribution source digital content data (distribution data), and the determination result is transmitted to the transmission unit 214. To the content use device 30. Then, data use performed in the content use device 30 is restricted by the control unit 307.

  Also in this modified example, in the first function calculation unit 311 in the content data alteration detection device 20, as shown in FIG. 3A, fingerprint verification for calculating a plurality of types of element data by calculating a plurality of types of functions is performed. .. Are provided, and during the identification process, the fingerprint verification units 311a to 311c... Perform fingerprint verification using a plurality of types of functions on each of the plurality of partial data. ing.

  Here, also in this modified example, the partial data extraction unit 321 is provided, and the first function calculation unit 311 and the second function calculation unit 312 generate element data and digest data for the extracted partial data. . In addition, the first function calculation unit 311 generates and identifies a plurality of types of element data for each function using a plurality of types of functions.

  Also in this modified example, when the first digital content data is viewed by a human, the first function outputs the digital content so as to output a value that does not change even if it is altered to the extent that the quality is not impaired. It shall have the characteristic which extracts the element which controls data quality. Similarly, it is assumed that the second function has a characteristic that the value to be output is changed when any one bit of the input digital content data is changed.

  As shown in FIG. 3B, each of the fingerprint verification units 311a to 311c... Includes a fingerprint calculation unit 3111 that calculates element data using a first function, and calculates weighting information for each partial data. An evaluation unit 3112 for calculating an evaluation value of data is provided.

  The fingerprint calculation unit 3111 is a module that calculates element data using functions assigned to the fingerprint verification units 311a to 311c. The evaluation unit 3112 calculates weighting information weight for the partial data extracted by the partial data extraction unit 321, acquires content data identification information and reliability information reliability for each partial data, and is most likely from these input information Content data identification information is calculated. These pieces of information are transmitted to the content utilization device 30 side as determination data D3. The control unit 307 in the content usage device 30 performs usage control based on the determination data D3 calculated by the evaluation unit 3112.

  Also in this modification example, the related information registration unit 400 may be installed so that it can be accessed from the collation unit 231 of the alteration detection device 20, and the collation result in the collation unit 231 may be registered in the related information registration unit 400. . In this case, the collation unit 231 searches the element data (fingerprint) in the collation process, and associates the digest data (hash value) corresponding to the retrieved element data in the related information registration unit 400. Collation is also performed for other hash values.

  According to such a modification, the content data modification detection device 20 side performs the pairing of the identification process, and the content use device 30 transmits the content data related to the identification to the content data modification detection device 20 side. It is possible to restrict playback by receiving a reply of the identification result, reduce processing on the content utilization device 30 side, and reduce the size and weight of the device.

[Modification 2]
Furthermore, in the first to third embodiments described above, the digital content data determination unit 230 related to reproduction is provided on the content data modification detection device 20 side. However, as shown in FIG. You may make it provide in the side.

  Specifically, as shown in the figure, the determination unit 230 is arranged between the first function calculation unit 311 and the second function calculation unit 312 and the reception unit 306 in the content utilization device 30 side. Then, the first function calculation unit 311 and the second function calculation unit 312 output the calculated element data D12 and digest data D22 to the determination unit 230, and correspond to the known and unknown digital content data D1 and D2, respectively. The element data D11 and the digest data D21 to be read are read from the database 210 provided on the content data alteration detection device 20 side, and identification processing is performed.

  More specifically, first, in the content use device 30, the element data D12 calculated by the first function calculation unit 311 is output to the first comparison unit 233, and the digest data D22 calculated by the second function calculation unit 312 is output as the second data. To the comparator 234.

  Next, the search unit 232 performs known and unknown stored in the database 210 on the content data modification detection device 20 side via the transmission unit 305 on the content use device 30 side and the reception unit 213 on the content use device side 20. The element data D11 and the digest data D21 corresponding to the digital content data D1 and D2 are searched and read out. The known digital content data D1 and the unknown digital content data D2 read from the database 210 are transmitted to the content utilization device 30 via the transmission unit 214 on the content utilization device side 20 and the reception unit 306 on the content utilization device 30 side. To the search unit 232 on the side.

  In FIG. 2, a database 210 is a recording unit that can be accessed from the person (service provider) who distributes the digital content data through the receiving unit 201. In this database 210, element data D11 obtained by executing the first function on the distribution source digital content data, and digest data D21 obtained by executing the second function on the distribution source digital content data. Is recorded.

  Then, the element data D11 read from the database 210 and the element data D12 are compared by the first comparison unit 233, and when it is detected that they match, the digest data D21 read from the database 210 is still detected. And the digest data D22 are compared in the second comparison unit 234.

  Further, in the second comparison, when it is detected that the data does not match, the collation unit 231 determines that the distributed digital content data has been modified from the distribution source digital content data (distribution data), and the determination result Is transmitted to the control unit 307. Then, the control unit 307 restricts data use.

  Here, also in this modified example, in the first function calculation unit 311 in the content utilization device 30, as shown in FIG. 3A, a fingerprint for calculating a plurality of types of element data by calculating a plurality of types of functions. Verification units 311a to 311c are provided, and during the identification process, the fingerprint verification units 311a to 311c are used to verify fingerprints using a plurality of types of functions for each of a plurality of partial data. It has become. Also in this modified example, the partial data extraction unit 321 is provided, and the first function calculation unit 311 and the second function calculation unit 312 generate element data and digest data for the extracted partial data.

  Further, also in the present modification example, the first comparison unit determines the identity of element data extracted by a plurality of types of functions from each of the digital content data D2 related to reproduction and the digital content data D1 related to distribution. Compare multiple functions. In addition, the collation unit 231 determines the identity of the known digital content data D1 and the unknown digital content data D2 according to the comparison result for each of a plurality of types of functions in the comparison unit 233.

  Also in this modified example, when the first digital content data is viewed by a human, the first function outputs the digital content so as to output a value that does not change even if it is altered to the extent that the quality is not impaired. It shall have the characteristic which extracts the element which controls data quality. Similarly, it is assumed that the second function has a characteristic that the value to be output is changed when any one bit of the input digital content data is changed.

  As shown in FIG. 3B, each of the fingerprint verification units 311a to 311c... Includes a fingerprint calculation unit 3111 that calculates element data using a first function, and calculates weighting information for each partial data. An evaluation unit 3112 for calculating an evaluation value of data is provided.

  The fingerprint calculation unit 3111 is a module that calculates element data using functions assigned to the fingerprint verification units 311a to 311c. Then, the converted element data is input to the determination unit 230 on the content utilization device 30 side, the element data is sequentially read from the database 210 of the content modification detection device 20 by the search unit 232, and is compared by the first comparison unit 233. The When the approximate element data is detected, the collation unit 231 collates the database 210, and the content data identification information for identifying the corresponding element data and the reliability indicating how probable the fingerprint collation is. Get information reliability. The content data identification information and reliability information reliability obtained in this way are input to the evaluation unit 3112 of the content utilization device 30 as determination data D3.

  The evaluation unit 3112 calculates weighting information weight for the partial data extracted by the partial data extraction unit 321, acquires content data identification information and reliability information reliability for each partial data, and is most likely from these input information Content data identification information is calculated. And the control part 307 in the content utilization apparatus 30 performs utilization control (reproduction | regeneration permission or reproduction | regeneration restriction | limiting) based on the determination data D3 which this evaluation part 3112 calculated.

  In this modified example, the related information registration unit 400 is installed so that it can be accessed from the collation unit 231 of the content use device 30, and the collation result in the collation unit 231 is registered in the related information registration unit 400. In this case, the collation unit 231 searches the element data (fingerprint) in the collation process, and associates the digest data (hash value) corresponding to the retrieved element data in the related information registration unit 400. Collation is also performed for other hash values.

  Also in this modified example, the control unit 307 includes a registration request unit 307a for registering related information. Then, when there are a plurality of search results by the search unit 232, the registration request unit 307a requests registration of related information that associates a plurality of digest data that are search results. The collation unit 231 requests the related information registration unit 400 to register related information in response to a request from the registration request unit 307 a, and the related information registration unit 400 registers the related information in the database 210 in response to this request.

  According to the present modification example, the content use device 30 side performs the pairing of the identification processing, and the content data modification detection device 20 side stores the element data D11 and the digest data D21 corresponding to the content data related to the identification. It transmits to the utilization apparatus 30 side. As a result, the processing on the content data alteration detection device 20 side can be reduced, and the processing of the device can be prevented from being concentrated on one point.

D01 ... Managed digital content data D02 ... Verification content data D03 ... Distribution content data D1 ... Known digital content data D2 ... Unknown digital content data D11 ... Known element data D12 ... Unknown element data D21 ... Known digest Data D22 ... Unknown digest data D3 ... Determination data D41 ... Hash value 10 ... Content distribution device 20 ... Content modification detection device 30 ... Content utilization device 101 ... Compression unit 102, 304 ... Decompression unit 103 ... Encryption unit 104 ... Distribution unit DESCRIPTION OF SYMBOLS 106 ... Content data ID management part 107 ... Conversion control part 111,311 ... 1st function calculating part 112,312 ... 2nd function calculating part 233 ... 1st comparison part 234 ... 2nd comparison part 201,213,301, 306 ... Receiver 210: Storage unit 211 ... Known data storage unit 105, 214, 305 ... Transmission unit 215 ... Data selection unit 230 ... Determination unit 231 ... Verification unit 302 ... External input unit 303 ... Decoding unit 307 ... Control unit 307a ... Registration request unit 308 ... Reproduction output unit 310 ... Storage device 311a ... Fingerprint verification unit 3111 ... Fingerprint calculation unit 3112 ... Evaluation unit 400 ... Related information registration unit

Claims (18)

A first function calculation unit that calculates element data extracted from the digital content data based on characteristics relating to the content of the digital content data by calculating a first function;
A second function calculation unit that calculates digest data extracted from the digital content data based on a bit arrangement of the digital content data by calculating a second function;
A database for storing the element data and the digest data in association with each other;
A search unit that searches the database for element data that is the same as or approximate to the element data extracted from the digital content data related to distribution, and obtains digest data associated with the searched same or approximate element data;
A verification unit that compares the digest data of the digital content data related to the distribution with the digest data searched by the search unit;
A content data management system comprising: a related information registration unit for registering related information for associating a plurality of searched digest data when there are a plurality of search results by the search unit. A first function calculation unit that calculates element data extracted from the digital content data based on characteristics relating to the content of the digital content data by calculating a first function;
A second function calculation unit that calculates digest data extracted from the digital content data based on a bit arrangement of the digital content data by calculating a second function;
A database for storing the element data and the digest data in association with each other;
A search unit that searches the database for element data that is the same as or approximate to the element data extracted from the digital content data related to distribution, and obtains digest data associated with the searched same or approximate element data;
A verification unit that compares the digest data of the digital content data related to the distribution with the digest data searched by the search unit;
A control unit for controlling the reproduction of the digital content data according to the comparison result of the verification unit,
The collation unit compares the plurality of searched digest data with the digest data of the digital content data related to the distribution when there are a plurality of search results by the search unit. Data management system. A partial data extraction unit for extracting a plurality of partial data from the digital content data;
The search unit performs the search for each of the plurality of partial data,
The related information, the management system of the content data according to claim 1 search result by the search unit When there are more than one, characterized in that associated with the retrieved plurality of digest data to each partial data. By calculating the first function, the element data extracted from the digital content data based on the characteristics relating to the contents of the digital content data is calculated, and the digital content data is calculated by calculating the second function. From the function calculation step of calculating digest data extracted based on the bit arrangement of the digital content data,
From a database for storing in association with the element data and the digest data, retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, the found identical or similar elements data A search step to obtain associated digest data;
Digest data of the digital content data according to the distribution, a matching step of comparing the identity of the digest data by the search unit has searched,
Wherein when the search Search Results step there are multiple, retrieved management method of the content data; and a related information registering step of a plurality of registers the related information associating the digest data. By calculating the first function, the element data extracted from the digital content data based on the characteristics relating to the contents of the digital content data is calculated, and the digital content data is calculated by calculating the second function. From the function calculation step of calculating digest data extracted based on the bit arrangement of the digital content data,
From a database for storing in association with the element data and the digest data, retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, the found identical or similar elements data A search step to obtain associated digest data;
Digest data of the digital content data according to the distribution, a matching step of comparing the identity of the digest data by the search unit has searched,
Depending on the comparison result at the comparison step, and a control step for controlling reproduction of the digital content data,
In the collation step, when there are a plurality of search results obtained in the search step, the same is also compared between the plurality of searched digest data and the digest data of the digital content data related to the distribution. Data management method. Said function is preceded computing step further has a partial data extraction step of extracting a plurality of partial data from the digital content data,
In the search step, the search is performed for each of the plurality of partial data,
5. The content data according to claim 4 , wherein, in the related information registration step, when there are a plurality of search results in the search step, related information that associates a plurality of searched digest data with each partial data is registered. Management method. A first function computing unit that computes element data extracted from the digital content data related to reproduction based on characteristics relating to the content of the digital content data by computing a first function;
A second function calculation unit that calculates digest data extracted from the digital content data related to reproduction based on the bit arrangement of the digital content data by calculating a second function;
From a database for storing in association with the element data and the digest data, retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, the found identical or similar elements data A search unit for obtaining associated digest data;
Digest data of the digital content data according to the distribution, a collating unit for comparing the identity of the digest data by the search unit has searched,
An apparatus for using content data, comprising: a registration request unit that requests registration of related information that associates a plurality of searched digest data when there are a plurality of search results by the search unit. A first function computing unit that computes element data extracted from the digital content data related to reproduction based on characteristics relating to the content of the digital content data by computing a first function;
A second function calculation unit that calculates digest data extracted from the digital content data related to reproduction based on the bit arrangement of the digital content data by calculating a second function;
A transmission unit for transmitting the element data and the digest data calculated by the first and second function calculation units to the management device;
A receiving unit that receives, from the management device, a determination result regarding the identity of the digital content data related to the reproduction and the known content data managed by the management device;
A database for storing in association with the digest data and the element data, when the element data to be the same as or close to the the element data extracted from the digital content data according to delivery there are multiple, related associating the plurality of digest data A content data utilization apparatus comprising: a registration request unit that requests registration of information. A transmission unit for transmitting digital content data relating to distribution to the management device;
A receiving unit that receives, from the management device, a determination result relating to the identity of the digital content data related to the distribution and the known content data managed by the management device;
When there is a plurality of element data that is the same as or similar to the element data extracted from the digital content data related to the distribution in the database that stores the element data and the digest data in association with each other, the related information for associating the plurality of digest data And a registration request part for requesting registration,
The determination regarding the identity is as follows:
By calculating the first function, element data extracted from the digital content data related to reproduction based on characteristics relating to the contents of the digital content data is calculated,
By calculating the second function, the digest data extracted based on the bit arrangement of the digital content data is calculated from the digital content data related to reproduction,
Search the database for element data that is the same or similar to the element data extracted from the digital content data related to the distribution, and obtain digest data associated with the searched same or similar element data,
An apparatus for using content data, wherein the digest data of the digital content data related to the distribution is compared with the searched digest data. A first function computing unit that computes element data extracted from the digital content data related to reproduction based on characteristics relating to the content of the digital content data by computing a first function;
A second function calculation unit that calculates digest data extracted from the digital content data related to reproduction based on the bit arrangement of the digital content data by calculating a second function;
From a database for storing in association with the element data and the digest data, retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, the found identical or similar elements data A search unit for obtaining associated digest data;
A verification unit that determines the identity of the digest data of the digital content data related to the distribution and the digest data searched by the search unit;
According to the result of by that determine the constant to the matching unit, and a control unit for controlling the playback of the digital content data according to the reproduction,
When there are a plurality of search results by the search unit, the matching unit also compares the plurality of searched digest data with the identity of the digest data of the digital content data related to the distribution.
An apparatus for using content data characterized by the above. A first function computing unit that computes element data extracted from the digital content data related to reproduction based on characteristics relating to the content of the digital content data by computing a first function;
A second function calculation unit that calculates digest data extracted from the digital content data related to reproduction based on the bit arrangement of the digital content data by calculating a second function;
A transmission unit for transmitting the element data and the digest data calculated by the first and second function calculation units to the management device;
A receiving unit that receives, from the management device, a determination result regarding the identity of the digital content data related to the reproduction and the known content data managed by the management device;
A control unit that controls reproduction of the digital content data related to the reproduction according to the determination result received by the reception unit, and
The determination regarding the identity is as follows:
From a database for storing in association with element data and the digest data, it retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, associated with the retrieved same or similar elements data Get the digest data,
Digest data of the digital content data in accordance with the distribution, to compare the identity of the retrieved the digest data, if the result of the search there are a plurality, a plurality of digest data retrieved, according to the distribution An apparatus for using content data, characterized in that it is performed by comparing the identity of digital content data with digest data. A transmission unit for transmitting digital content data relating to distribution to the management device;
A receiving unit that receives, from the management device, a determination result relating to the identity of the digital content data related to the distribution and the known content data managed by the management device;
Depending on the said reception unit receives a determination result, and a control unit for controlling the playback of the digital content data according to the playback,
The determination regarding the identity is as follows:
By calculating the first function, element data extracted from the digital content data related to reproduction based on characteristics relating to the contents of the digital content data is calculated,
By calculating the second function, the digital content data according to the reproduction, it calculates the digest data extracted based on the bit sequence of the digital content data,
The element data for the same or similar as has been the element data extracted from the digital content data according to the distribution, retrieves from the database, obtains the digest data associated with the retrieved same or similar elements data,
Digest data of the digital content data in accordance with the distribution, to compare the identity of the retrieved the digest data, if the result of the search there are a plurality, a plurality of digest data retrieved, according to the distribution An apparatus for using content data, characterized in that it is performed by comparing the identity of digital content data with digest data. A partial data extraction unit for extracting a plurality of partial data from the digital content data;
The search unit may perform the search for each of the plurality of partial data,
The content data utilization apparatus according to claim 7 , wherein the related information associates a plurality of searched digest data for each partial data when there are a plurality of search results by the search unit. A first function calculation unit that calculates element data extracted from the digital content data based on characteristics relating to the content of the digital content data by calculating a first function;
A second function calculation unit that calculates digest data extracted from the digital content data based on a bit arrangement of the digital content data by calculating a second function;
From a database for storing in association with the element data and the digest data, retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, the found identical or similar elements data A search unit for obtaining associated digest data;
Digest data of the digital content data according to the distribution, a collating unit for comparing the identity of the digest data by the search unit has searched,
A content data management apparatus comprising: a related information registration unit for registering related information for associating a plurality of searched digest data when there are a plurality of search results by the search unit. By calculating the first function, the element data extracted from the digital content data related to the distribution based on the characteristics relating to the contents of the digital content data and the second function are calculated, thereby calculating the first function. A receiver for receiving digest data extracted from the digital content data based on the bit arrangement of the digital content data;
From the database that stores the element data and the digest data in association with each other, element data that is the same as or similar to the element data extracted from the digital content data related to the distribution is searched, and the searched element data that is the same or approximate A search unit for obtaining associated digest data;
A verification unit that compares the digest data of the digital content data related to the distribution with the digest data searched by the search unit;
A content data management apparatus comprising: a related information registration unit for registering related information for associating a plurality of searched digest data when there are a plurality of search results by the search unit. A first function calculation unit that calculates element data extracted from the digital content data based on characteristics relating to the content of the digital content data by calculating a first function;
A second function calculation unit that calculates digest data extracted from the digital content data based on a bit arrangement of the digital content data by calculating a second function;
From a database for storing in association with the element data and the digest data, retrieves the element data to be the same as or close to the extracted element data from the digital content data according to delivery, the found identical or similar elements data A search unit for obtaining associated digest data;
Digest data of the digital content data according to the distribution, a collating unit for comparing the identity of the digest data by the search unit has searched,
A control unit that controls reproduction of the digital content data in accordance with a result of comparison by the verification unit;
The collation unit compares the plurality of searched digest data with the digest data of the digital content data related to the distribution when there are a plurality of search results by the search unit. Data management device. By calculating the first function, the element data extracted from the digital content data related to the distribution based on the characteristics relating to the contents of the digital content data and the second function are calculated, thereby calculating the first function. A receiver for receiving digest data extracted from the digital content data based on the bit arrangement of the digital content data;
From the database that stores the element data and the digest data in association with each other, element data that is the same as or similar to the element data extracted from the digital content data related to the distribution is searched, and the searched element data that is the same or approximate A search unit for obtaining associated digest data;
A verification unit that compares the digest data of the digital content data related to the distribution with the digest data searched by the search unit;
A control unit that controls reproduction of the digital content data in accordance with a result of comparison by the verification unit;
The collation unit compares the plurality of searched digest data with the digest data of the digital content data related to the distribution when there are a plurality of search results by the search unit. Data management device. A partial data extraction unit for extracting a plurality of partial data from the digital content data;
The search unit performs the search for each of the plurality of partial data,
16. The content data management apparatus according to claim 14 , wherein the related information associates a plurality of searched digest data for each partial data when there are a plurality of search results.