JP4642372B2 - Digital content playback apparatus and digital content playback method - Google Patents

Description

  The present invention relates to a digital content playback apparatus, and more particularly to a digital content playback apparatus capable of protecting rights related to digital content.

  In recent years, systems for distributing digital works such as music, video, and games over the Internet and digital broadcasting have been developed, and some of them are in the stage of practical use. Also, in the distribution of these contents, a content usage control system that restricts the number of reproductions, movement, copying, and the like of the distributed contents has been studied from the viewpoint of copyright protection.

  In a conventional digital content distribution system, usage conditions for each user's content are distributed to the user terminal together with the content, and the user terminal manages the usage of the content based on the distributed usage conditions (Patent Document 1). reference.).

For example, when a user purchases the right to watch a movie “EIGA” for one hour, the user terminal can “view EIGA for one hour” together with the content of the movie “EIGA” from the distribution server. A usage rule indicating that the content is present is received, and reproduction of the content is managed according to the usage rule. In this case, when the user terminal reproduces the content “EIGA”, the reproduction time is measured, and when the reproduction time reaches 1 hour, viewing is not permitted.
Japanese Patent Application Laid-Open No. 08-54951

  However, in the conventional technology, usage control in the case where the content is composed of a plurality of elements is not considered well, and there is a possibility that the content cannot be used against the user's intention. There is a problem. Specifically, for example, in the use of content composed of song data, lyrics data, artist image data, etc., since the user has viewed the lyrics data for a long time, all the right to use the content is consumed. This may lead to a situation where it becomes impossible to reproduce the song data.

  The present invention has been conceived in accordance with such a situation, and an object of the present invention is to provide a mechanism that makes it possible to appropriately control the use of content composed of a plurality of elements. .

  In order to solve the above problems, a digital content playback apparatus of the present invention is a digital content playback apparatus that plays back the content according to license information that permits playback of the content, and is a content that includes a plurality of elements that can be played back individually. A license information acquisition unit that acquires license information indicating the reproducible amount, and a reproduction that determines whether or not the element included in the content is reproducible based on the reproducible amount indicated in the acquired license information The apparatus includes: a determination unit for determining whether or not the element can be reproduced; and a reproduction unit that does not reproduce the element when the element is determined to be unreproducible.

  In addition, the playability determination unit specifies a right consuming element that consumes the playable amount by playing among the elements being played, and sets the play amount and the playable amount of the specified right consumption element. Based on this, whether or not the element in the content can be reproduced may be determined.

  Further, the license information further includes rights consuming element information indicating a rights consuming element included in each content, and the reproduction permission / inhibition judging means determines the rights consuming element being reproduced based on the rights consuming element information. A consumption amount calculating unit that calculates the consumption amount of the reproducible amount according to the specified reproduction amount of the specified right consumption element, and the reproducible amount indicated in the acquired license information A comparison unit that compares the consumption amount, and the playability determination unit determines that the element in the content is playable while the consumption amount is less than the playable amount as a result of the comparison, When the consumption amount is equal to or greater than the reproducible amount, the element in the content may be determined to be unreproducible.

  The reproducible amount is represented by a reproducible amount of each element included in the content, and the reproducibility determination means includes the reproducible amount of each element indicated in the acquired license information, A comparison unit that compares the reproduction amount of each element, and the reproducibility determination unit determines that the element is reproducible as a result of the comparison while the replay amount is less than the reproducible amount, and When the reproduction amount becomes equal to or greater than the reproducible amount, each element may be determined to be unreproducible.

  The reproducible amount further includes, for each element, another element-dependent condition that determines whether or not the element can be reproduced according to whether or not another specific element included in the same content can be reproduced. When it is determined that the specific element indicated by the other element dependency condition of each element is not playable, the playability determination unit is configured to play the element even if the play amount is less than the playable amount. May be determined to be impossible.

As described above, according to the present invention, it is possible to obtain an effect that it is possible to appropriately perform usage control of content including a plurality of elements.
The present invention can be realized not only as such a digital content distribution system, but also as a single unit such as a rights management server and a user terminal constituting these digital content distribution systems, or by distributing these digital content distribution systems. It can also be realized as a rights management method having a characteristic operation in the system as a step, or as a program that causes a general-purpose computer such as a personal computer to execute the characteristic operation. Needless to say, the program can be distributed via a computer-readable recording medium such as a CD-ROM or a transmission medium such as the Internet.

(Embodiment 1)
FIG. 1 is a block diagram showing the overall configuration of a digital content distribution system according to Embodiment 1 of the present invention. In FIG. 1, the digital content distribution system includes at least one license server 100, at least one content server 101, at least one user terminal 110, and a transmission path 120. Hereinafter, each component of the digital content distribution system will be described. In the following description, the same components as those already described are denoted by the same reference numerals, and description thereof is omitted.

  The license server 100 is a server that is installed on the provider α side involved in content distribution and manages the usage rights for each content, and after performing necessary accounting processing in response to a license purchase request from the user terminal 110. The license 500 illustrated in FIG. 5 is distributed to the user terminal 110. The license 500 will be described in detail later.

Similar to the license server 100, the content server 101 is installed on the provider α side and distributes the content data 200 to the user terminal 110.
FIG. 2 is a diagram showing an example of content data 200 distributed by the content server 101 shown in FIG. As shown in FIG. 2, the content data 200 includes a content ID 201, element management information 202, and N encrypted elements 203. Here, N is an integer of 1 or more. The content ID 201 is an ID that uniquely identifies the content data 200 in the digital content distribution system. The element management information 202 is information for managing the encrypted element 203 included in the content data 200. The encryption element 203 encrypts music data, video data, lyrics data, and the like.

  FIG. 3 is a diagram showing an example of the element management information 202 shown in FIG. In FIG. 3, an element ID 300 is an ID that uniquely identifies the encrypted element 203 included in the content data 200 within the content data 200. The element type 301 is information indicating the type of the encryption element 203 such as “music data”, “video data”, and the like. The offset 302 is offset information indicating the distance from the beginning of the content data 200 to the encryption element 203. The element size 303 is the size of the encryption element 203. In FIG. 3, for example, the encrypted element 203 whose element ID 300 is “xxx001” has an element type 301 of “music data”, an offset 302 of “96000 bytes”, and an element size 303 of “512000 bytes”. It is shown that.

  FIG. 4 is a diagram illustrating an example of the usage right consumption target element designation information 204. As shown in FIG. 4, the usage right consumption target element designation information 204 indicates which encryption element 203 is the target for consuming the usage right among the encryption elements 203 included in the content data 200.

  In FIG. 4, the element ID 300 is the same as the element ID 300 of the element management information 202, and the usage right consumption flag 400 is a flag indicating whether or not the encryption element 203 is a target for consuming the usage right. In FIG. 4, the encrypted element 203 whose element ID 300 is “xxx001” is a target that consumes usage rights, and the encrypted elements whose element ID 300 is “xxx002” and “xxx003”. An element 203 indicates that the usage right is not consumed.

Returning to FIG. 1, the user terminal 110 is a terminal that receives the content distribution service, and is installed on the user β side.
The transmission path 120 is a wired transmission path or a wireless transmission path, and connects the license server 100 and the content server 101 to the user terminal 110 so that data communication is possible.

  In the present embodiment, the license server 100 and the content server 101 are installed on the same provider α side. However, the provider that operates the license server 100 and the provider that operates the content server 101 are used. And may be separate. Further, the license server 100 and the content server 101 have been described as being separate servers, but the same server may be used.

  Next, the license 500 distributed from the license server 100 to the user terminal 110 will be described with reference to FIG. FIG. 5 is a diagram illustrating an example of a license 500 distributed from the license server 100 illustrated in FIG. 1 to the user terminal 110. The license 500 includes a license ID 501, a content ID 201, a content usable time 502, an N set of an element ID 300 and a decryption key 503, the usage right consumption target element designation information 204 described with reference to FIG. Usage time 504. The license ID 501 is an ID that uniquely identifies the license 500 in the digital content distribution system. In the content ID 201, the content ID 201 of the content data 200 to which the license 500 is applied is described. The content available time 502 is information indicating the time when the content can be used. The decryption key 503 is a decryption key for decrypting the encrypted element 203 specified by the element ID 300. The content use time 504 is a time when the content is actually used. The initial value of the content usage time 504 is 0, and the value is updated every time the content is actually used. The license 500 is used until the content usage time 504 reaches the content usage time 502. It is determined that it is possible to use the content by using. Note that the content usage time 504 does not exist at the stage of distribution from the license server 100 to the user terminal 110 and may be added at the user terminal 110.

  Next, a specific configuration of the user terminal 110 will be described with reference to FIG. FIG. 6 is a block diagram showing a configuration of user terminal 110 shown in FIG. 6, the user terminal 110 includes a content database 600, a license database 601, a communication unit 602, a license purchase unit 603, an availability determination unit 604, a decryption key acquisition unit 605, a decryption unit 606, and a playback. A display unit 607, a usage status management unit 608, and a license update unit 609 are included. Hereinafter, each component of the user terminal 110 will be described.

The content database 600 is a database that manages the content data 200 distributed from the content server 101.
The license database 601 is a database that securely manages the license 500 distributed from the license server 100.

The communication unit 602 communicates with the license server 100 and the content server 101 via the transmission path 120.
The license purchase unit 603 is a processing unit that makes a license purchase request to the license server 100 and acquires the license 500.

  The availability determination unit 604 is a processing unit that refers to the content availability time 502 and the content usage time 504 in the license 500 and determines whether the content is available.

The decryption key acquisition unit 605 is a processing unit that extracts a necessary decryption key 503 from the license 500 stored in the license database 601.
The decryption unit 606 is a processing unit that extracts the content data 200 from the content database 600 and decrypts the encrypted element 203 in the extracted content data 200 using the decryption key 503 acquired by the decryption key acquisition unit 605.

  The playback / display unit 607 is a processing unit that plays back or displays the encrypted element 203 decrypted by the decryption unit 606. Specifically, the playback / display unit 607, for example, when the encrypted element 203 to be played back is a music element, a process of expanding the compression encoding of data to the decrypted encrypted element 203, etc. To generate sound data and output it to a speaker or the like. Further, when the encrypted element 203 to be reproduced is, for example, a moving image element, the decrypted encrypted element 203 is subjected to a process for expanding and compressing the data to generate moving image data, and the monitor Output to.

  The usage status management unit 608 measures the usage time of each element included in the content, and performs an operation of stopping the usage of the content as necessary, for example, when all usage rights are consumed. Note that the usage status management unit 608 measures the time during which the element that is the usage right consumption target is used as the time when the content is used.

  The license update unit 609 updates the license 500 stored in the license database 601. Specifically, it is assumed that when content is used, an operation of updating the content usage time 504 in the license 500 is performed.

This is the end of the description of the user terminal 110.
Next, the operation of the digital content distribution system in the present embodiment will be described using a flowchart. FIG. 7 is a flowchart showing an operation when the user terminal 110 uses content. FIG. 8 is a flowchart showing the operation of the availability determination process. FIG. 9 is a flowchart showing the operation of the element usage start process. FIG. 10 is a flowchart showing the operation of the content using process.

First, an operation when the user terminal 110 uses content will be described with reference to a flowchart of FIG.
The availability determination unit 604 receives a content usage start instruction from the user β through a user operation input unit (not shown) such as a keyboard, and starts the following processing. It is assumed that the content use start instruction from the user β includes information for designating the content and element to be used.

S701: The availability determination unit 604 performs an availability determination process described later with reference to the flowchart of FIG. 8, and determines whether the content can be used.
S702: If it is determined that the content can be used in S701, the process proceeds to S703. If it is determined that the content cannot be used, the process proceeds to S707.

S703: An element use start process described later with reference to the flowchart of FIG. 9 is performed, and use of the element requested to be used is started.
S704: The content using process described later with reference to the flowchart of FIG. 10 is executed.

  S705: The usage status management unit 608 determines whether or not usage of all elements has been suspended. If all the elements have been suspended, the process proceeds to S706. If there is an element being used, the process returns to S704.

  S706: The license update unit 609 updates the content usage time 504 in the license 500 based on the content usage time measured by the usage status management unit 608 in the content usage process of S704.

S707: Notify the user that the content cannot be used.
This is the end of the description of the operation when the user terminal 110 uses content.

Next, the usability determination process in S701 in FIG. 7 will be described with reference to the flowchart in FIG.
S801: The availability determination unit 604 checks whether the license 500 corresponding to the content that the user β wants to use exists in the license database 601. If the corresponding license 500 exists, the process proceeds to S802. If the corresponding license 500 does not exist, the process proceeds to S804.

  S802: The availability determination unit 604 determines whether the content usage time 504 of the license 500 corresponding to the content that the user β wants to use is less than the content usage time 502. If the content usage time 504 is less than the content usage time 502, the processing proceeds to S803. If the content usage time 504 is not less than the content usage time 502, the processing proceeds to S804.

S803: The availability determination unit 604 determines that the content can be used.
S804: The availability determination unit 604 determines that the content cannot be used.
This is the end of the description of the availability determination process.

Next, the element use start process in S703 in FIG. 7 will be described with reference to the flowchart in FIG.
S901: The decryption key acquisition unit 605 extracts the decryption key 503 corresponding to the encryption element 203 that the user β desires to use from the license 500 stored in the license database 601.

  S902: The decryption unit 606 extracts the encryption element 203 that the user β desires to use from the content data 200 stored in the content database 600, and uses the decryption key 503 acquired by the decryption key acquisition unit 605 in S901. To decrypt.

S903: The reproduction / display unit 607 reproduces / displays the encrypted element 203 decrypted by the decryption unit 606 in S902.
This is the end of the description of the element usage start process.

Next, the content using process in S704 in FIG. 7 will be described with reference to the flowchart in FIG.
S1001: A content usage time measurement control process to be described later with reference to the flowchart of FIG. 11 is performed.

  S1002: The usage status management unit 608 determines whether or not to continue using the content. The determination as to whether or not the content use can be continued is made based on whether or not the condition of (Expression 1) is satisfied. If the condition of (Expression 1) is satisfied, the content use can be continued, and (Expression 1) When the condition is not satisfied, it is determined that the content use cannot be continued.

(Content usage time measured by usage status management unit 608) <(Content available time 502 of license 500 used for content usage)-(Content usage time of license 500 used for content usage) 504) (Equation 1)
If it is determined in S1002 that the content use can be continued, the process proceeds to S1004. If it is determined that the content use cannot be continued, the process proceeds to S1003.

  S1003: The usage status management unit 608 instructs the playback / display unit 607 to stop playback / display of all elements. The playback / display unit 607 stops playback / display of all elements in accordance with instructions from the usage status management unit 608.

  S1004: The usage status management unit 608 determines whether any instruction is received from the user β regarding the use of the element. If an instruction has been received from the user β, the process proceeds to S1005. If no instruction is received from the user β, no process is performed and the content using process is terminated.

  S1005: If the instruction received from the user β is an instruction to start using a new element, the process proceeds to S1006. If the instruction received from the user β is an instruction to stop using the element being used, the process proceeds to S1007.

S1006: The element use start process described with reference to FIG. 9 is executed, and the reproduction / display of the element instructed to start use by the user β is started.
S1007: The usage status management unit 608 instructs the playback / display unit 607 to stop playback / display of the element for which usage stop has been instructed by the user β. The reproduction / display unit 607 stops reproduction / display of the element instructed to stop use.

This is the end of the description of the content using process.
Next, the content usage time measurement control process of S1001 in FIG. 10 will be described with reference to the flowchart of FIG. FIG. 11 is a flowchart showing the operation of the content usage time measurement control process.

  S1101: The usage status management unit 608 refers to the usage right consumption target element designation information 204 included in the license 500 being used, and determines whether the element of the right consumption target is being used. If the element for rights consumption is being used, the process proceeds to S1102. If the rights consumption target element is not being used, the process proceeds to S1103.

  S1102: The usage status management unit 608 adds the content usage time for each right consumption target element being used. More specifically, when the processing of S1102 is executed for the first time after receiving the content usage start instruction, for example, a timer for measuring elapsed time with an initial value of 0 is started. Then, when the processing of S1102 is executed next, the elapsed time measured so far is added to a register for calculating the content usage time for each right consumption target element being used. Thereafter, the process of starting the measurement of the elapsed time from 0 again is performed by the timer. However, the initial value of the register is 0. Also, (content usage time measured by the usage status management unit 608) in (Equation 1) is the sum of the elapsed time in each register added to each right consumption target element so far.

  S1103: The usage status management unit 608 stops adding the content usage time. Specifically, each register to which the elapsed time is added for each right consumption target element holds the added elapsed time as it is.

  This is the end of the description of the content usage time measurement control process. In the flowchart of FIG. 11, the content usage time measurement control process in the case where the usage time is added by the number of usage right consumption target elements used in parallel has been described. That is, when the three usage right consumption target elements are used in parallel for 1 minute, (Content usage time measured by the usage status management unit 608) of (Equation 1) is equal to the measured elapsed time. It was calculated as 3 minutes, 3 times. However, the present invention is not limited to this. For example, even when a plurality of usage right consumption target elements are used in parallel, the number of usage right consumption target elements being used may be calculated as 1, and the measured elapsed time may be added to the content usage time. . That is, the content usage time may be calculated based only on whether or not at least one usage right consumption target element is used. In this case, even if the three usage right consumption target elements are used in parallel for 1 minute, the content usage time is calculated as 1 minute, which is the measured elapsed time itself.

This is the end of the description of the operation of the digital content distribution system in the present embodiment.
In the present embodiment, the usage right consumption target element designation information 204 has been described as being included in the license 500, but the present invention is not limited to this. FIG. 12 is a diagram showing another example of the content data 200 shown in FIG. That is, the usage right consumption target element designation information 204 may not be included in the license 500 but may be included in the content data 200 as shown in FIG.

  In the present embodiment, the usage right consumption target element designation information 204 has been described as information consisting of a set of the element ID 300 and the usage right consumption flag 400, but the present invention is not limited to this. FIG. 13 is a diagram showing another example of the usage right consumption target element designation information 204 shown in FIG. For example, as shown in FIG. 13, the usage right consumption target element designation information 204 divides elements into a group of elements that are usage rights consumption targets and a group of elements that are not usage rights consumption targets, and element IDs are assigned. It may be a listed list. FIG. 14 is a diagram showing still another example of the usage right consumption target element designation information 204 shown in FIG. As shown in FIG. 14, the usage right consumption target element designation information 204 may simply be a list describing element IDs 300 of elements that are usage right consumption targets.

  FIG. 15 is a diagram showing still another example of the usage right consumption target element designation information 204 shown in FIG. As illustrated in FIG. 15, the information may be information including a set of an element ID 300 and a usage right consumption degree 1300. The usage right consumption level 1300 is information indicating how much usage rights each element consumes, and the usage status management unit 608 measures content usage time based on this information. For example, the content usage time when an element set to “1/2 consumption” is used for 1 minute is “30 seconds”.

  FIG. 16 is a flowchart showing another example of the operation of the content usage time measurement control process shown in FIG. Specifically, it is a flowchart showing an operation when the usage status management unit 608 measures the content usage time according to the usage right consumption target element designation information 204 shown in FIG.

  S2201: The usage status management unit 608 refers to the usage right consumption target element designation information 204 shown in FIG. 15 included in the license 500 being used, and the total n (n is n) of the usage right consumption levels 1300 of the elements being used. A positive real number). For example, when an element with an element ID “xxx001”, an element with an element ID “xxx002”, and an element with an element ID “xxx003” are in use, n = 0.5 + 2 + 0 = 2.5.

  S2202: The usage status management unit 608 determines whether or not the calculated total n of usage right consumption levels 1300 is greater than zero. When the total n of the usage right consumption levels 1300 is larger than 0, the processing proceeds to S2203. If the total n of the usage right consumption levels 1300 is not greater than 0 (that is, n = 0), the process proceeds to S2204.

  S2203: The usage status management unit 608 multiplies the content usage time by n and adds it. More specifically, when the process of S2203 is executed for the first time after receiving the content use start instruction, for example, a timer that measures an elapsed time with an initial value of 0 is started. Then, when the process of S2203 is executed next, the elapsed time measured so far is multiplied by n and added to the register, and the timer performs the process of starting the elapsed time measurement from 0 again. However, the initial value of the register is 0. Therefore, for example, when the element with the element ID “xxx001”, the element with the element ID “xxx002”, and the element with the element ID “xxx003” are used in parallel for one minute, The content usage time is calculated as 2 minutes 30 seconds.

S2204: Usage status management section 608 stops adding content usage time.
By calculating the content usage time as described above, it is possible to control the content usage time according to the usage right consumption level 1300 of the element. In the flowchart shown in FIG. 16, the total n of the usage rights consumption levels 1300 of the elements being used is calculated, and the measured elapsed time is multiplied by n and added to the register. However, the present invention is not limited to this. Not. For example, among the elements in use, only the element whose usage right consumption level 1300 has the maximum value m is subject to calculation of the content usage time, and the elapsed time measured while the element is being played is multiplied by m. May be added to the register. That is, the element with the element ID “xxx001”, the element with the element ID “xxx002”, and the element ID “xxx003” indicated by the usage right consumption target element designation information 204 shown in FIG. May be calculated only for the element having the maximum value m = 2 of the usage right consumption degree 1300. In this case, the content usage time is 2 minutes.

  In the above-described embodiment, the element that is the usage right consumption target is specified using the usage right consumption target element designation information 204, but the present invention is not limited to this. Specifically, in the content data 200 shown in FIG. 2, for example, the encryption element # 1 and the encryption element # 2 may be determined to be usage right consumption objects. In this case, if there is only one element that is subject to consumption rights consumption, for example, stuffing data or the like is packed in the encryption element # 2, and elements that are not consumption rights consumption elements are described after the encryption element # 3. That's fine.

  In the above embodiment, when the difference between the content available time (or the number of times the content can be used) and the content use time (or the number of times the content is used) becomes 0, that is, when the right to use the content according to the license 500 is lost, Although all the elements are unavailable, the present invention is not limited to this. For example, an element that is not a usage right consumption target may be usable even after the right to use the content by the license 500 has been exhausted.

  In the present embodiment, the content usage time 502 is used as the usage right included in the license 500. However, the present invention is not limited to this. FIG. 17 is a diagram showing another example of the license 500 shown in FIG. For example, as shown in FIG. 17, the license 500 includes a content usage count 1400 and a content usage count 1401 instead of the content usage time 502 and the content usage time 504 shown in FIG. 5. To do. The content usage count 1400 is the number of times the content can be used, and the content usage count 1401 is the number of times the content has been actually used. In this case, the usage status management unit 608 performs control as if the content was used “once” when an element that is a right consumption target was used.

  As described above, according to the present embodiment, for example, in the usage control of content including song data, lyrics data, artist image data, etc., song data is a right consumption target element, and other data is a right consumption target. If it is set not to be an element, it prevents the situation where the user consumes all the right to use the content because he / she has viewed the lyrics data for a long time and cannot play the important song data. Is possible.

This completes the description of the first embodiment of the present invention.
(Embodiment 2)
Next, a digital content distribution system in Embodiment 2 of the present invention will be described. The digital content distribution system according to the second embodiment has almost the same configuration as the digital content distribution system according to the first embodiment, and the operation thereof is only partially different. Therefore, only the differences from the first embodiment are specified here. In addition, in the drawings, the same components are given the same reference numerals for explanation.

Since the overall configuration of the digital content distribution system and the configuration of the user terminal 110 in the second embodiment are the same as those in the first embodiment, description thereof will be omitted.
FIG. 18 is a diagram illustrating a configuration of the license 500 according to the second embodiment. The difference between the license 500 in the second embodiment and the license 500 in the first embodiment is that the content usable time 502 and the content usable time 504 are not provided, but instead, the usable time and the usable time for each element are described. The element usable time 1600 and the element usable time 1601 are included, and the other element dependency information 1602 is further included. The other element dependency information 1602 is information that describes the usage status of another element as a condition that the element can be used for each element. For example, “use right of an element having an element ID of xxx111” It is assumed that a condition such as “remaining” is described.

19 to 21 are flowcharts showing the operation of the digital content distribution system in the second embodiment.
First, the operation when the user terminal 110 according to the second embodiment uses the elements will be described with reference to the flowchart of FIG.

  The availability determination unit 604 receives an element usage start instruction from the user β through a user operation input unit (not shown) such as a keyboard. It is assumed that the element use start instruction from the user β includes information for designating an element to be used.

  S1701: The availability determination unit 604 performs an availability determination process, which will be described later with reference to the flowchart of FIG. 20, and determines whether or not the element instructed to be used by the user β can be used.

S1702: If it is determined in S1701 that the element can be used, the process proceeds to S1703. If it is determined that the element cannot be used, the process proceeds to S1708.
S1703: The element usage start process described with reference to the flowchart of FIG. 9 is executed, and the usage of the element requested to be used is started.

S1704: The usage status management unit 608 starts measuring the usage time of the element.
S1705: An element using process described later with reference to the flowchart of FIG. 21 is performed.

  S1706: The usage status management unit 608 determines whether the usage of the element is stopped. If the use of the element is stopped, the process proceeds to S1707. If the use of the element is not stopped, the process returns to S1705.

  S 1707: The license update unit 609 updates the element usage time 1601 in the license 500 based on the element usage time measured by the usage status management unit 608.

S1708: Notifying the user that the element is unavailable.
This is the end of the description of the operation when the user terminal 110 in Embodiment 2 uses the element.

Next, the usability determination process in S1701 in FIG. 19 will be described with reference to the flowchart in FIG.
S1801: The availability determination unit 604 checks whether the license 500 corresponding to the element that the user β desires to use exists in the license database 601. If the corresponding license 500 exists, the process proceeds to S1802. If the corresponding license 500 does not exist, the process proceeds to S1805.

  S1802: The availability determination unit 604 determines whether the element usage time 1601 corresponding to the element that the user β desires to use is less than the element usage time 1600. If the element usage time 1601 is less than the element usage time 1600, the process proceeds to S1803. If the element usage time 1601 is not less than the element usage time 1600, the process proceeds to S1805.

  S1803: The availability determination unit 604 determines whether the condition described in the other element dependency information 1602 is satisfied. If the condition described in the other element dependency information 1602 is satisfied, the process proceeds to S1804. If the condition described in the other element dependency information 1602 is not satisfied, the process proceeds to S1805.

S1804: The availability determination unit 604 determines that the element can be used.
S1805: The availability determination unit 604 determines that the element cannot be used.
This is the end of the description of the availability determination process.

Next, the element using process in S1705 in FIG. 19 will be described with reference to the flowchart in FIG.
S1901: The usage status management unit 608 determines whether or not the available time of the element remains. This determination is made depending on whether or not the condition of (Expression 2) is satisfied. When the condition of (Expression 2) is satisfied, it is determined that the available time of the element remains, and (Expression 2 ), It is determined that there is no remaining usable time for the element.

(Element usage time measured by the usage status management unit 608) <(Element available time 1600 corresponding to the element being used)-(Element usage time 1601 corresponding to the element being used) Formula 2)
If it is determined in S1901 that the available time of the element remains, the process proceeds to S1902. If it is determined that the available time of the element does not remain, the process proceeds to S1904.

  S1902: The availability determination unit 604 determines whether the condition described in the other element dependency information 1602 is satisfied. If the condition described in the other element dependency information 1602 is satisfied, the process proceeds to S1903. If the condition described in the other element dependency information 1602 is not satisfied, the process proceeds to S1904.

  S1903: The usage status management unit 608 determines whether or not an element usage stop instruction has been received from the user β. If an element use stop instruction has been received from the user β, the process proceeds to S1904. If no element use stop instruction has been received from the user β, no process is performed and the element using process is terminated.

  S1904: The usage status management unit 608 instructs the playback / display unit 607 to stop playback / display of the element. The playback / display unit 607 stops playback / display of the element.

This completes the description of the element using process.
As described above, according to the present embodiment, for example, in the use control of content including song data, lyrics data, artist image data, etc., the element usable time corresponding to the lyrics data or artist image data If “Infinite” is set in 1600 and “Song data usage rights remain” is set in the other element-dependent information 1602, the user has viewed the lyrics data for a long time. It is possible to prevent the situation in which the use of other elements is stopped, and at the same time, the use of other elements is stopped when the right to use the song data is lost.

  This is the end of the description of the second embodiment of the present invention.

  The user terminal of the present invention is useful as a content playback device having a communication function, a personal computer, a PDA (Personal Digital Assistant), a mobile phone, an STB (Set Top Box), and the like. The right management server of the present invention is useful as a server that distributes a license for using content to a user terminal via a communication network such as a broadcast network or the Internet. The digital content distribution system of the present invention distributes a digital content license such as video or music from a rights management server to a user terminal via a communication network such as a broadcast network or the Internet, and the user terminal is based on the distributed license. This is useful as a content use system that uses digital content.

It is a figure which shows the structure of the whole digital content delivery system in Embodiment 1 of this invention. It is a figure which shows an example of the content data delivered by the content server shown in FIG. It is a figure which shows an example of the element management information shown in FIG. It is a figure which shows an example of utilization right consumption object element designation | designated information. It is a figure which shows an example of the license delivered to a user terminal from the license server shown in FIG. It is a block diagram which shows the structure of the user terminal shown in FIG. It is a flowchart which shows the operation | movement at the time of a user terminal using a content. It is a flowchart which shows operation | movement of the availability determination process shown in FIG. It is a flowchart which shows operation | movement of the element utilization start process shown in FIG. It is a flowchart which shows operation | movement of the content utilization process shown in FIG. It is a flowchart which shows operation | movement of the content utilization time measurement control process shown in FIG. It is a figure which shows the other example of the content data shown in FIG. It is a figure which shows the other example of the usage right consumption object element designation | designated information shown in FIG. It is a figure which shows the further another example of the utilization right consumption object element designation | designated information shown in FIG. It is a figure which shows the further another example of the utilization right consumption object element designation | designated information shown in FIG. 12 is a flowchart showing another example of the operation of the content usage time measurement control process shown in FIG. FIG. 6 is a diagram illustrating another example of the license illustrated in FIG. 5. FIG. 10 is a diagram showing an example of a license in the second embodiment. It is a flowchart which shows the operation | movement at the time of the user terminal 110 using an element. FIG. 20 is a flowchart showing the operation of the availability determination process shown in FIG. 19. FIG. FIG. 20 is a flowchart showing the operation of the element using process shown in FIG. 19. FIG.

Explanation of symbols

100 license server 101 content server 110 user terminal 201 content ID
202 Element management information 203 Encrypted element 204 Usage right consumption target element designation information 300 Element ID
301 Element type 302 Offset 303 Element size 400 Usage right consumption flag 500 License 501 License ID
502 Content Usable Time 503 Decryption Key 504 Content Use Time 600 Content Database 601 License Database 602 Communication Unit 603 License Purchasing Unit 604 Usability Determining Unit 605 Decryption Key Acquisition Unit 606 Decryption Unit 607 Playback / Display Unit 608 Usage Status Management Unit 609 License Update unit 1300 Usage rights consumption frequency 1400 Content usage count 1401 Content usage count 1600 Element usage time 1601 Element usage time 1602 Other element dependent information

Claims (13)

The content comprising a plurality renewable individually element, a digital content reproducing apparatus to play in accordance with the license information for permitting the reproduction of the content,
The individual rather than the renewable content of each renewable plurality of elements, the license information shown renewable amount of the entire contents consisting of a plurality renewable individually element, communication network, broadcasting waves and recording medium License information acquisition means for acquiring via any one of
Before Symbol of the elements being reproduced in the content, the specific rights consumption element is one or more kinds of elements predetermined consuming renewable amount of the total content indicated in the acquired license information Then, the playback amount of the entire content is calculated by adding the playback amount of only the specified one or more rights consuming elements, and is included in the calculated playback amount of the entire content and the license information. Reproducibility determining means for determining reproducibility of the rights consuming element by comparing the reproducible amount of the entire content;
Digital content comprising: playback means for playing back the rights consuming element when the rights consuming element is determined to be playable, and playing back the rights consuming element when the rights consuming element is determined not to be playable Playback device. The license information further includes right consumption element information indicating a right consumption element included in each content,
The reproducibility determining means is
A consumption amount calculation unit that identifies a right consumption element that is being reproduced based on the right consumption element information, and calculates a consumption amount of the reproducible amount of the entire content according to the reproduction amount of the identified right consumption element; ,
A comparison unit that compares the reproducible amount of the entire content indicated in the acquired license information with the calculated consumption amount;
The playability determination unit determines that the element in the content can be played back while the consumption amount is less than the playable amount of the entire content as a result of the comparison, and the consumption amount can play back the entire content. The digital content playback apparatus according to claim 1, wherein an element in the content is determined to be unplayable when the amount exceeds the limit. The right consumption element information is composed of a set of an element identifier for identifying each element included in the content and a flag indicating whether or not each element is the right consumption element,
The consumption calculation unit reproduces by identifying an element included in the content being reproduced by the element identifier included in the right consumption element information and referring to the flag corresponding to the element identifier of the identified element. The digital content playback apparatus according to claim 2, wherein a right consumption element included in the content is specified. The right consumption element information is an element for grouping the elements included in the content into a group of the right consumption element and a group that is not the right consumption element, and identifying an element belonging to each group. Are listed using identifiers,
The consumption amount calculation unit reproduces the element identifier of each element included in the content being reproduced with the element identifier belonging to the group of the right consumption element described in the right consumption element information. The digital content playback apparatus according to claim 2, wherein a right consumption element included in the content is specified. The right consumption element information is a list of elements that are the right consumption elements, using element identifiers for identifying each element,
The consumption calculation unit compares the element identifier of each element included in the content being played back with the element identifier listed in the right consumption element information, thereby the right included in the content being played back The digital content playback apparatus according to claim 2, wherein a consumption element is specified. The right consuming element information is composed of a set of an element identifier for identifying each element included in the content and a consumption frequency indicating a ratio of the reproduction amount of each element to the reproduction amount of the entire content,
The consumption amount calculation unit compares the element identifier of each element included in the content being played back with the element identifier included in the right consumption element information, so that the right consumption included in the content being played back The element is specified, and the total time obtained by multiplying the playback time of each right consumption element specified during playback by the consumption frequency for each right consumption element is calculated, and the calculated total is used as the entire content. The digital content playback apparatus according to claim 2, wherein the playback amount of The consumption calculation unit calculates a time obtained by multiplying the reproduction time of the right consumption element having the maximum consumption frequency by the maximum consumption frequency among the right consumption elements identified during the reproduction, and calculates the calculated The digital content playback apparatus according to claim 6, wherein time is set as a playback amount of the right consuming element. The consumption amount calculation unit calculates a total reproduction time of each right consumption element specified during reproduction, and uses the calculated total as a reproduction amount as the entire content. The digital content reproduction apparatus described. The content further includes rights consuming element information indicating the one or more rights consuming elements,
The reproducibility determining means is
A consumption calculating unit for identifying the right consumption element being reproduced based on the right consumption element information and calculating a reproduction amount of the specified right consumption element;
A comparison unit that compares the reproducible amount of the entire content indicated in the acquired license information with the calculated replay amount of the right consumption element;
The playability determination unit determines that the rights consuming element in the content is playable while the playback amount of the right consumption element is less than the playable amount of the entire content as a result of the comparison, and the rights consumption element The digital content playback apparatus according to claim 1, wherein when the playback amount of the element is greater than or equal to the playable amount of the entire content, the right consuming element in the content is determined to be unplayable. The content is composed of a plurality of encrypted elements,
The license information includes one or more decryption keys for individually decrypting one or more encrypted elements included in the content,
The digital reproduction device according to claim 1, wherein the reproduction means reproduces after decrypting an encrypted element included in the content determined to be reproducible using a decryption key included in the license information. Content playback device. The content comprising a plurality of elements that can be reproduced individually, a digital contents reproducing method in a digital content playing device to play in accordance with the license information for permitting the reproduction of the content,
The digital content reproduction apparatus is
The individual rather than the renewable content of each renewable plurality of elements, the license information shown renewable amount of the entire contents consisting of a plurality renewable individually element, communication network, broadcasting waves and recording medium A license information acquisition step to acquire via any one of the following:
Before Symbol of the elements being reproduced in the content, the specific rights consumption element is one or more kinds of elements predetermined consuming renewable amount of the total content indicated in the acquired license information Then, the playback amount of the entire content is calculated by adding the playback amount of only the specified one or more rights consuming elements, and is included in the calculated playback amount of the entire content and the license information. A reproducibility determining step for determining whether or not the right consuming element can be replayed by comparing the reproducible amount of the entire content;
A digital content comprising: a playback step of playing back the rights consuming element when the rights consuming element is determined to be playable; and playing back the rights consuming element when the rights consuming element is determined not to be playable. Playback method. The license information further includes right consumption element information indicating a right consumption element included in each content,
The reproducibility determination step includes
A consumption amount calculating step for identifying a right consumption element that is being reproduced based on the right consumption element information, and calculating a consumption amount of the reproducible amount according to a reproduction amount of the identified right consumption element;
Includes a shown in the acquired license information reproducible amounts were calculated and comparison step of comparing the consumption,
In the playability determination step, as a result of the comparison, while the consumption amount is less than the playable amount, it is determined that the element in the content is playable, and when the consumption amount is equal to or greater than the playable amount, The digital content playback method according to claim 11, wherein an element in the content is determined to be unplayable.   11. A program for a digital content playback apparatus that plays back the content in accordance with license information that permits the playback of the content, the computer comprising the computer as a unit included in the digital content playback apparatus according to claim 1. A program to make it work.

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