Copy protection

• US 20070245370A1
• Filed: 03/23/2007
• Published: 10/18/2007
• Est. Priority Date: 03/24/2006
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Kim, In Moon
• Granted Patent: US 7,945,925 B2
• Time in Patent Office: Days
• US Class Current: 725/31
• CPC Class Codes: H04H 60/16 on playing information
• CPC Class Codes: H04H 60/18 on copying information
• CPC Class Codes: H04H 60/23 using cryptography, e.g. encryption, authentication, key distribution
• CPC Class Codes: H04N 2005/91328 the copy protection signal being a copy management signal, e.g. a copy generation management signal [CGMS]
• CPC Class Codes: H04N 2005/91364 the video signal being scrambled
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/4181 for conditional access
• CPC Class Codes: H04N 21/435 Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/8352 involving content or source identification data, e.g. Unique Material Identifier [UMID]
• CPC Class Codes: H04N 21/8355 involving usage data, e.g. number of copies or viewings allowed
• CPC Class Codes: H04N 5/913 for scrambling ; for copy protection
• CPC Class Codes: H04N 7/163 by receiver means only

Abstract

An apparatus for copy protection in a cable broadcast receiver and method thereof are disclosed, by which digital broadcast contents can be protected from being copied.

Claims

1. A method of copy protection in a cable broadcast receiver, the method comprising the steps of:

receiving a multi-stream broadcast signal;

assigning a unique stream identifier to each stream of the multi-stream broadcast signal;

receiving copy control information to which the stream identifier is assigned;

matching the stream and the copy control information using the stream identifier;

storing the matched copy control information; and

controlling an output of a broadcast stream using a value of the stored copy control information.

2. The method of claim 1, wherein the stream identifier is an LTSID assigned by a host and wherein the LTSID is assigned per multi-stream not to be duplicated.

3. The method of claim 1, further comprising the steps of:

generating a scramble key and a descramble key by giving the stream identifier assigned to the stream; and

scrambling and descrambling the stream having the same stream identifier assigned thereto using the scramble key and the descramble key.

4. The method of claim 1, wherein the stream and the copy control information having the same stream identifier are matched to be tablized.

5. The method of claim 1, wherein if a value of the copy control information of the broadcast signal stream is changed, the value of most recently received copy control information matched to the stream identifier assigned to the stream is stored.

6. The method of claim 1, wherein in the step of controlling the output of the broadcast stream, the received copy control information is applied per the stream by real time.

7. The method of claim 1, wherein in the step of controlling the output of the broadcast stream, outputs of a plurality of streams are multiply controlled by applying a plurality of copy control information values to a plurality of the streams, respectively.

8. A cable broadcast receiver, which receives a multi-stream broadcast signal, the cable broadcast receiver comprising:

a broadcast receiving unit receiving a multi-stream broadcast signal;

a CAS module unit assigning a unique stream identifier to each stream of the received multi-stream broadcast signal; and

a control unit controlling copy control information matched to the stream identifier assigned to the stream to be stored, the control unit controlling an output of a broadcast stream using a value of the stored copy control information.

9. The cable broadcast receiver of claim 8, wherein the stream identifier is an LTSID assigned by a host and wherein the LTSID is assigned per multi-stream not to be duplicated.

10. The cable broadcast receiver of claim 8, wherein the control unit matches the stream and the copy control information having the same stream identifier to tablize.

11. The cable broadcast receiver of claim 8, further comprising a storage unit storing a table generated from matching the stream identifier, the stream and the copy control information.

12. The cable broadcast receiver of claim 8, wherein if the value of the copy control information of the broadcast signal stream is changed, the control unit controls to store a value of most recently received copy control information matched to the stream identifier assigned to the stream.

13. The cable broadcast receiver of claim 8, wherein the control unit controls copying of an outputted broadcast signal by applying the received copy control information per the stream by real time.

14. The cable broadcast receiver of claim 8, wherein if an output signal of a stream is inputted, the control unit controls the output of the stream using the copy control information to which has an identifier identical to the stream identifier assigned to the stream.

15. The cable broadcast receiver of claim 8, further comprising a copy protection processing unit generating a descramble key by giving the stream identifier assigned by the CAS module unit to the descramble key, the copy protection processing unit descrambling a scrambled stream having the same stream identifier using the descramble key.

16. A copy protection system receiving a multi-stream broadcast signal, comprising:

a host receiving the multi-stream broadcast signal, the host assigning a unique stream identifier to a header of a received multi-stream per stream; and

a cable card receiving the multi-stream to which the stream identifier is assigned from the host, the cable card storing header information of the stream, the cable card assigning the stored header information to copy control information, the cable card conveying the copy control information to the host,

wherein the host stores the copy control information and the stream to which the same stream identifier is assigned and then controls an output of the stream using the copy control information matched to the stream identifier.

17. The copy protection system of claim 16, wherein the host assigns an LTSID as the stream identifier and wherein the LTSID is assigned per multi-stream not to be duplicated.

18. The copy protection system of claim 16, wherein the host generates a descramble key by giving the stream identifier to the descramble key and wherein the cable card generates a scramble key by giving the stream identifier to the scramble key.

19. The copy protection system of claim 18, wherein the cable card scrambles a corresponding stream using the scramble key matched as having the same stream identifier and wherein the host descrambles the corresponding stream using the descramble key matched as having the same stream identifier.

20. The copy protection system of claim 16, wherein if a value of the copy control information is changed, copying of an outputted broadcast signal is controlled in a manner of storing a value of most recently received copy control information matched to the stream identifier assigned to the stream and applying the copy control information per the stream by real time.