JP3425534B2 - Broadcast storage device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a broadcast storage device that stores scrambled broadcast programs, descrambles them, and reproduces them, and more particularly, to prevent deterioration of security such as a scramble key.

[0002]

2. Description of the Related Art Conventionally, when a pay program is broadcast, a broadcast station scrambles a broadcast program consisting of video and audio with a scramble key Ks and transmits the scramble key Ks, and the scramble key Ks is used for ECM (Entitlement Control Messages). : Common information), and the common information ECM is stored in the work key Kw.
Encrypt with and send. The work key Kw is E
MM (Entitlement Management Messages: Individual information)
Stored in, the individual information EMM is encrypted with the individual key Km, and is transmitted to each receiving side in advance.

On the other hand, on the receiving side, when the encrypted individual information EMM is received, the individual key Km held in advance is received.
And decrypts the work key Kw from the EMM. Further, the EMM includes tier information indicating a program having a viewing right, and the like.
Hold with w.

Further, when the scrambled broadcast program and the encrypted common information ECM are received, the ECM is decrypted with the work key Kw to extract the scramble key Ks from the ECM, and the program tier included in the ECM. When it is confirmed from the information that the viewer has the viewing right, the scrambled broadcast program is descrambled using the extracted Ks.

Further, a broadcast storage device for storing and reproducing the scrambled broadcast program has conventionally stored the scrambled broadcast program together with the ECM, and when reproducing, the EC
It is configured to decode M, extract Ks, and use the Ks to descramble the broadcast program to be reproduced.

FIG. 7 shows the structure of this broadcast storage device. This apparatus includes a demultiplexing unit 101 for demultiplexing multiplexed signals, an EMM decoding unit 109 for decoding the demultiplexed EMM using Km held in a Km management unit 112, and a demultiplexing process from the decoded EMM. The individual information management unit 110 for managing the individual information and the E separated by using the decrypted Kw.
ECM decoding unit 107 for decoding CM, viewing right determination unit 111 for checking the viewing right by collating the program information extracted from the ECM with the individual information, and outputting Ks decoded from the ECM when the viewing right is possessed Ks output control unit 108 and Ks
The descrambling unit 104 that descrambles the video / audio data using the Ks output from the output control unit 108, and the display control unit 105 that controls the display of the video / audio on the display unit 106.
And a storage control unit 10 for controlling storage of video and audio and ECM
2 and a storage device I / that interfaces with the storage device
It is equipped with F103.

The Km management unit 112, the EMM decoding unit 109,
Individual information management unit 110, ECM decoding unit 107, viewing right determination unit 11
The 1 and Ks output control units 108 are configured in a security module such as an IC card.

In this apparatus, the multiplexed and broadcast data is input to the separating unit 101, and the separating unit 101 separates the multiplexed data. The separated EMM is an EMM decoding unit.
Ks decrypted in 109 and extracted from EMM is ECM
The individual information set in the decryption unit 107 and extracted from the EMM is accumulated in the individual information management unit 110.

When viewing a broadcast program in real time, the components of the broadcast program (video, audio, E
EC that has been separated by the separation unit 101 and encrypted
M is input to the ECM decoding unit 107, and the scrambled video / audio is input to the descramble unit 104. EC
The M decoding unit 107 decodes the ECM using Kw,
The Ks extracted from M is output to the Ks output control unit 108,
In addition, the program tier information extracted from the ECM is output to the viewing right determination unit 111. The viewing right determination unit 111 compares the program tier information with the individual information, and outputs the viewing right determination result to the Ks output control unit 108. When the viewing right is recognized, the Ks output control unit 108 outputs Ks. Is output to the descrambling unit 104. The descrambling unit 104 descrambles the video and audio using this Ks, and the descrambled video and audio is displayed on the display device 106 under the control of the display control unit 105.

Further, when a broadcast program is stored, the components (video, audio, ECM) of the broadcast program are output from the separation unit 101 to the storage control unit 102 while being scrambled and encrypted, and the storage device The data is stored in the storage device using a magnetic tape or the like as a recording medium through the I / F 103.

FIG. 8 shows a TS stored in a storage device of a system (first storage system) for storing broadcast programs and ECMs.
(Transport Stream) Indicates a stream of packets. This stream is the audio of one program that has been accumulated.
Partial TS consisting of (audio) and Video
The ECM is recorded and generated in the above null packet (there is a null packet between TS packets) at the timing when it was broadcast.

When the broadcast program stored in the storage device is reproduced and viewed, the TS stream of FIG. 8 is read from the storage device via the storage device I / F 103, and the separation unit 101
To enter. The separation unit 101 separates this into an ECM and a video / audio signal, and the ECM is sent to the ECM decoding unit 107 and the video / audio signal.
The audio signal is output to the descrambling unit 104. The subsequent operation is the same as in the case of real-time viewing. The ECM decoding unit 107 decodes the ECM using Kw, outputs Ks to the Ks output control unit 108, and outputs the program tier information to the viewing right determination unit 111. Output. The viewing right determination unit 111 compares the program tier information with the individual information, and determines the viewing right determination result by Ks.
The Ks output control unit 108 outputs the Ks to the descrambling unit 104 when the viewing right is recognized. The descrambling unit 104 descrambles the video and audio using this Ks, and the descrambled video and audio is displayed on the display device 106 under the control of the display control unit 105.

In addition, components of a broadcast program (video,
When accumulating and recording voice and ECM), a method of accumulating encrypted EMMs (second accumulation method) has also been developed. In this method, as shown in FIG. 9, the EMM is recorded prior to the accumulation of broadcast programs, and thereafter,
The EMM is recorded in the null packet on the partial TS accumulated at an arbitrary time granularity.

When reproducing and viewing the accumulated broadcast programs,
Broadcast programs (video / audio signals), ECM and E from the storage device
The MM and the EMM are retrieved, the EMM is decrypted by the EMM decryption unit 109 of the security module using the Km held in the Km management unit 112, and the EMM is retrieved from the EMM.
w is set in the ECM decoding unit 107, and the individual information extracted from the EMM is accumulated in the individual information management unit 110. The subsequent operation is the same as that of the first storage method described above.

The broadcast program stored by the second storage method can be reproduced and viewed only by the receiving device that stores the EMM.

[0016]

However, in the first storage method and the second storage method, the ECM and EMM are recorded together with the broadcast program in the recording medium of the storage device. When a magnetic tape or the like having low (tamper) property (hard to open, property to break when opened) is used, the security of the ECM or EMM may be compromised, and so-called security strength may be lowered. is there.

However, in the case of storing using an IC card or the like having a high tampering property, there is a problem that the amount of data is large and the capacity of the IC card cannot keep up because the video and audio data are combined. .

The present invention solves these conventional problems, and an object of the present invention is to provide a broadcast storage device with high security strength.

[0019]

Therefore, in the broadcast storage device of the present invention, the ECM and the video / audio data of the broadcast program are separated and stored in different recording media.

Further, control information for synchronizing with video / audio data is added when the ECM is stored.

Therefore, the ECM can be stored in the memory having a small storage capacity but high tampering property, and the security strength can be enhanced.

Further, the ECM does not have the synchronization information with the broadcast program, but by adding the synchronization information when the ECM is stored, it becomes possible to descramble the video / audio data at the time of reproduction.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is a broadcast storage device for storing / reproducing a scrambled broadcast program, wherein the multiplexed ECM and broadcast program video / audio data. And separate them into the ECM
Attach control information to synchronize with the video / audio data
In addition, the ECM and the video / audio data are stored in different recording media, and the storage capacity required for the recording medium for ECM storage is reduced, and a memory with high tampering property is stored in the ECM. Can be used for.
In addition, by adding control information, ECM can be used for video / audio data.
Play back in sync with the video and audio data
It becomes possible to bully.

[0024]

According to the second aspect of the present invention, when the ECM is accumulated, the ECM corresponding to a specific scene is invalidated to restrict playback and viewing of the scene.
If is disabled, it becomes impossible to reproduce and view the scene to which the scramble key is supplied by the ECM.

According to the third aspect of the present invention, the ECM is invalidated on the basis of the instruction included in the broadcasted information, and the broadcast station side specifies the scene for which reproduction / viewing is restricted. Will be possible.

According to a fourth aspect of the present invention, when the viewing restriction is added to the information defining the scene in the received program index, the ECM corresponding to the corresponding scene.
Is invalidated, and the broadcasting station can specify a scene whose reproduction and viewing are restricted in the program index to be broadcast. The invention according to claim 5 is such that the ECM is compressed and accumulated when the ECM is accumulated. For example, when the ECM having the same Ks is repeatedly broadcast, the ECM having the updated Ks.
It makes efficient use of storage capacity by storing only.

According to a sixth aspect of the present invention, the ECM is stored in a memory having a high tampering property, and the ECM is stored using a memory having a high confidentiality holding performance such as a memory card or a memory stick. To be done.

According to a seventh aspect of the invention, the ECM is stored in a built-in security module, and the ECM can be stored in an IC card built in or inserted into the receiving device. .

According to the invention described in claim 8 , the ECM is stored on the home server, and the ECM is stored on the home server separately from the video / audio, and at the time of reproduction, the video is sent from the home server. -Read the voice and ECM and play them on the receiving device.

According to a ninth aspect of the present invention, the sending rate from the storage device of the ECM is controlled to suppress fast-forwarding and rewinding during playback viewing, and the CM is skipped at fast-forwarding and played back. You can limit things.

According to the tenth aspect of the present invention, the output from the ECM storage device is stopped when the CM is not viewed, and it is possible to limit the CM skip during reproduction.

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) As shown in FIG. 1, the broadcast storage device of the first embodiment separates a separated unit 201 for separating multiplexed signals and separated video / audio data. A descramble unit 206 for descrambling, a display control unit 207 for controlling display of video / audio on the display unit 208, a storage control unit 203 for controlling storage of video / audio data, and a storage device for video / audio data A storage device I / F 202 for interfacing with E and an ECM synchronization code generation code
The CM synchronization control unit 204 and the ECM storage device I / F 205 that interface with the storage device that stores the ECM are provided, and the Km management unit is provided in the security module.
214, an EMM decoding unit 211, an individual information management unit 213, an ECM decoding unit 209, a viewing right determination unit 212 and a Ks output control unit 210 are provided.

In this apparatus, when viewing a broadcast program in real time, the same operation as described with reference to FIG. 7 is performed.

When storing broadcast programs, the separation unit 201
The video / audio data separated by the storage control unit 203
To the ECM separated by the separation unit 201.
Is input to the ECM synchronization control unit 204. The video / audio data input to the storage control unit 203 is output through the storage device I / F 202 and stored in the video / audio storage device.

The ECM sync control unit 204 inputs the ECM
A sync code for synchronizing the video data with the video / audio data, and the ECM to which the sync code is added is stored in the ECM storage device I.
Output to / F205. This ECM is an ECM storage device I
The data is output from the / F205 to the ECM storage device that stores the ECM and stored.

FIG. 2 shows the E recorded in the ECM storage device.
The CM is shown.

When the stored broadcast program is viewed, the video / audio output from the storage device is stored in the storage device I.
It is input to the separation unit 201 via / F202, separated into video and audio signals by the separation unit 201, and input to the descramble unit 206.

On the other hand, the EC output from the ECM storage device
The M is input to the ECM synchronization control unit 204 via the ECM storage device I / F 205. The ECM synchronization control unit 204 cooperates with the display control unit 207 and outputs the ECM to the ECM decoding unit 209 according to the output state of video / audio based on the synchronization code.

The ECM decoding unit 209 decodes this ECM using the Kw set by the EMM decoding unit 211, outputs the Ks extracted from the ECM to the Ks output control unit 210, and the program extracted from the ECM. The tier information is output to the viewing right determination unit 212. The viewing right determination unit 212 collates the individual information managed by the individual information management unit 213 with the program tier information, outputs the result of the viewing right determination to the Ks output control unit 210, and the Ks output control unit 210. Outputs Ks to the descrambling unit 206 when the viewing right is recognized.
The descrambler 206 descrambles the video and audio using this Ks, and the descrambled video and audio is displayed on the display 208 under the control of the display controller 207.

FIG. 3 shows the relationship among the receiving device 41, the video / audio storage device 43, and the ECM storage device 43 for storing ECM. When receiving the broadcast and storing the broadcast program, the receiving device 41 including the security module 42 outputs the video / audio to the storing device 43 and outputs the ECM to the EC.
Output to the M storage device 43. The video / audio storage device 43 includes, for example, a normal VT that uses a magnetic tape as a recording medium.
R is used, and as the ECM storage device 43, a storage device having a high tampering property using a memory card or a memory stick as a recording medium is used.

Further, as shown in FIG. 4, the video / audio is stored in the video / audio storage device 43, and the ECM is the receiving device.
It may be recorded in the security module 42 included in 41.

Further, as shown in FIG. 5, the home server 44
Is installed so that the video / audio of the broadcast program and the ECM are separately stored in the home server 44, and the video / audio and the ECM are sent from the home server 44 to the receiving device 41 during playback and viewing. Is also good.

As described above, in this broadcast storage device, since the video / audio of the broadcast program and the ECM are stored separately, E
The CM storage device may have a small storage capacity.
Therefore, it is possible to use a highly tampering storage device as the ECM storage device, thereby increasing the security strength.

Further, in this broadcast storage device, in order to reproduce and view video / audio, it is necessary to synchronize and reproduce separately stored video / audio data and ECM, which is utilized. ECM from the ECM storage device
It is possible to suppress the fast-forwarding and rewinding by controlling the sending rate of C, and by suppressing the fast-forwarding and rewinding, C
Partial viewing in which M is skipped and reproduced can be rejected.

Further, the CM skipping can be avoided by stopping the ECM output from the ECM storage device when the CM is not viewed.

At present, Ks is updated at 1 second intervals, but the ECM for updating Ks is broadcast at shorter intervals. Therefore, it means that the ECM having the same Ks is repeatedly broadcast, but when the ECM is stored, it is compressed and stored by a method such as storing only the ECM having the updated new Ks. By doing so, the accumulated amount can be reduced.

(Second Embodiment) In the broadcast storage apparatus of the second embodiment, the ECM for a temporary period can be invalidated so that a specific scene cannot be seen during reproduction.

As shown in FIG. 6, this apparatus has a program index storage management unit 317 that stores and manages broadcast program indexes, and an ECM invalidation control unit 316 that invalidates the ECM in the period designated by the program index. It has and. Other configurations are the same as those of the first embodiment (FIG. 1).

In this broadcast storage device, the separation unit 301 separates video / audio data from the received signal of the broadcast and outputs it to the descrambling unit 306 and the storage control unit 303, separates the ECM, and the ECM decoding unit 309. And the ECM invalidation control unit 316, and the program index is separated and output to the program index storage management unit 317. The program index includes information that defines a scene, and the program index storage management unit 317 stores this program index, and if viewing restriction information for the scene is added to the program index, the specified index is designated. EC to disable the ECM of the scene
The M invalidation control unit 316 is instructed.

In response to this, the ECM invalidation control unit 316 invalidates the input ECM to generate the ECM synchronization control unit 304.
Output to.

The ECM synchronization control unit 304 inputs the ECM
Is output to the ECM storage device I / F 305 by adding a synchronization code to the ECM storage device I / F 305.
It is output to the M storage device and stored. Thus ECM
The storage device has an EC with a specific ECM disabled.
M is accumulated.

When viewing the stored broadcast program, the video / audio data output from the storage device is stored in the storage device I.
The descrambling unit 306 via the F / F 302 and the separating unit 301.
To enter.

Further, the EC output from the ECM storage device
The M is input to the ECM synchronization control unit 304 via the ECM storage device I / F 305, and the ECM synchronization control unit 304 outputs the ECM to the ECM decoding unit 309 in synchronization with the video / audio.

The ECM decoding unit 309 uses the Kw to ECM
Is decoded and Ks extracted from the ECM is output to the Ks output control unit 310, and the program tier information extracted from the ECM is output to the viewing right determination unit 312. Viewing right determination unit 312
Determines the viewing right based on this, outputs the determination result to the Ks output control unit 310, and the Ks output control unit 310 outputs Ks to the descrambling unit 306 when the viewing right is recognized,
The descrambler 306 uses this Ks to descramble the video and audio. The descrambled video / audio is displayed on the display unit 308 under the control of the display control unit 307.

However, when the ECM is invalidated, the video and audio that should be descrambled with Ks included in the ECM is not descrambled and the scene cannot be viewed.

As described above, in the broadcast storage device of this embodiment, the broadcast side adds the parental control information to the information of the program index defining the scene to invalidate the ECM of the corresponding scene and reproduce the broadcast program. Viewing can be partially restricted. Although the case where the broadcast side specifies the invalidation of the ECM has been described here, the present invention is not limited to this. For example, a viewer who is recording a program for a child may be an EC of a scene that seems unsuitable for the child.
You can manually disable M, or decide a time and EC
It is also possible to specify invalidation of M.

[0059]

As is apparent from the above description, the broadcast storage device of the present invention can maintain the security of ECM and EMM and can maintain high security strength.

Also, in viewing the accumulated programs, CM
You can limit the skipping.

Further, by invalidating the ECM, it is possible to easily limit the reproduction / viewing of a specific scene.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a broadcast storage device according to a first embodiment of the present invention,

FIG. 2 is a diagram showing an ECM recording format in the ECM storage device of the first embodiment,

FIG. 3 is a diagram showing a video / audio storage device and an ECM storage device in the broadcast storage device of the first embodiment;

FIG. 4 is a block diagram showing an EC in the broadcast storage device of the first embodiment.
Configuration diagram when security module stores M

FIG. 5 is a diagram showing a form in which ECM is stored using a home server in the broadcast storage device according to the first embodiment;

FIG. 6 is a block diagram showing a configuration of a broadcast storage device according to a second embodiment of the present invention,

FIG. 7 is a block diagram showing a configuration of a conventional broadcast storage device,

FIG. 8 is a diagram showing a TS stream stored in a conventional broadcast storage device of a first storage system;

[Fig. 9] Fig. 9 is a diagram showing a TS stream stored in a broadcast storage device of a second conventional storage system.

[Explanation of symbols]

101, 201, 301 Separation part 102, 203, 303 Storage controller 103, 202, 302 Storage device I / F 104, 206, 306 Descramble section 105, 207, 307 Display control unit 106, 208, 308 Display 107, 209, 309 ECM decoding unit 108, 210, 310 Ks output controller 109, 211, 311 EMM decoding unit 110, 213, 313 Individual Information Management Department 111, 212, 312 Viewing right judgment section 112, 214, 314 Km Management Department 204, 304 ECM synchronization control unit 205, 305 ECM storage device I / F 316 ECM invalidation control unit 317 Program Index Storage Management Department

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Claims (10)

(57) [Claims] 1. In a broadcast storage device for storing and reproducing a scrambled broadcast program, the multiplexed ECM and video / audio data of the broadcast program are separated, and the video / audio data is stored in the ECM.
Control information for synchronizing with the ECM,
A broadcast storage device, wherein the video / audio data is stored in different recording media. To 2. During the accumulation of the ECM, and disable the ECM corresponding to a particular scene, a broadcast storing apparatus according to claim 1, characterized in that to limit the playback viewing the scene. 3. A process according to claim 2, characterized in that invalidates the ECM based on an instruction included in the broadcast information
The broadcast storage device according to. 4. Among the program index received, when it is added viewing restriction information defining the scene, according to claim 3, characterized in that disabling the ECM corresponding to the appropriate scene Broadcast storage device. 5. The broadcast storage device according to claim 1 , wherein the ECM is compressed and stored when the ECM is stored. 6. The broadcast storage device according to claim 1, wherein the ECM is stored in a memory having a high tampering property. 7. The broadcast storage device according to claim 1, wherein the ECM is stored on a built-in security module. 8. The broadcast storage device according to claim 1, wherein the ECM is stored on a home server. 9. The broadcast storage device according to claim 1, wherein a sending rate from the storage device of the ECM is controlled to suppress fast-forwarding and rewinding during playback and viewing. 10. The output from the storage device of the ECM is:
The broadcast storage device according to claim 1, wherein the broadcast storage device is stopped when the CM is not viewed.