Progressive video refresh slice detection

• US 20030156718A1
• Filed: 11/25/2002
• Published: 08/21/2003
• Est. Priority Date: 01/02/2002
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Candelore, Brant L., Pedlow, Leo M. Jr., Derovanessian, Henry
• Granted Patent: US 7,292,691 B2
• Time in Patent Office: Days
• US Class Current: 380/211
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• CPC Class Codes: H04N 21/2365 Multiplexing of several video streams
• CPC Class Codes: H04N 21/25875 involving end-user authentication restricting access to computer systems by authenticating users using a predetermined code G06F21/33; arrangements for secret or secure communication including means for verifying the identity or authority of a user of the system H04L9/32; networks authentication protocols H04L63/08; authentication in wireless network security H04W12/06
• CPC Class Codes: H04N 21/26606 for generating or managing entitlement messages, e.g. Entitlement Control Message [ECM] or Entitlement Management Message [EMM] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/4344 Remultiplexing of multiplex streams, e.g. by modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/4345 Extraction or processing of SI, e.g. extracting service information from an MPEG stream
• CPC Class Codes: H04N 21/4347 Demultiplexing of several video streams
• CPC Class Codes: H04N 21/43607 Interfacing a plurality of external cards, e.g. through a DVB Common Interface [DVB-CI]
• CPC Class Codes: H04N 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• CPC Class Codes: H04N 21/4516 involving client characteristics, e.g. Set-Top-Box type, software version or amount of memory available
• CPC Class Codes: H04N 21/454 Content or additional data filtering, e.g. blocking advertisements
• CPC Class Codes: H04N 21/4623 Processing of entitlement messages, e.g. ECM [Entitlement Control Message] or EMM [Entitlement Management Message] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 7/162 Authorising the user terminal, e.g. by paying; Registering the use of a subscription channel, e.g. billing
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

A selective encryption encoder and method of dual selective encryption and detection of intra-coded slices in video content. The selective encryption encoder has a packet identifier that identifies packets of at least one specified packet type, the at least one specified packet type being packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices. A packet duplicator duplicates the identified packets to produce first and second sets of the identified packets. The packets are sent to and from a primary encryption encoder to encrypt the first set of identified packets under a first encryption method. A secondary encrypter encrypts the second set of identified packets under a second encryption method.

Claims

1. A method of partially dual encrypting a digital video signal, comprising:

examining unencrypted packets of data in the digital video signal to identify at least one specified packet type, the at least one specified packet type comprising packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices;

encrypting packets identified as being of the specified packet type using a first encryption method to produce first encrypted packets;

encrypting the packets identified as being of the specified packet type using a second encryption method to produce second encrypted packets; and

replacing the unencrypted packets of the specified packet type with the first encrypted packets and the second encrypted packets in the digital video signal to produce a partially dual encrypted video signal.

2. The method according to claim 1, wherein the encrypting comprises encrypting packets containing slice headers for the N consecutive slices.

3. The method according to claim 1, wherein the encrypting comprises encrypting packets containing intra-coded macroblocks in the N consecutive slices.

4. The method according to claim 1, wherein the at least one specified packet type further comprises packets containing data from a first macroblock following the video slice header in the N consecutive slices.

5. The method according to claim 1, wherein N is between 1 and 10.

6. A computer readable medium storing instructions which, when executed on a programmed processor, carry out the method of encrypting a digital video signal according to claim 1.

7. The computer readable medium of claim 6, wherein the medium comprises one of an electronic storage medium and a carrier wave.

8. An electronic transmission medium carrying an encrypted digital video signal encrypted by the method according to claim 1.

14. A computer readable medium storing instructions which, when executed on a programmed processor, carry out the method of encrypting a digital video signal according to claim 8.

15. The computer readable medium of claim 14, wherein the medium comprises one of an electronic storage medium and a carrier wave.

33. The method according to claim 1, wherein N is between 1 and 10.

9. A method of partially encrypting a digital video signal, comprising:

examining unencrypted packets of data in the digital video signal to identify at least one specified packet type, the at least one specified packet type comprising packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices;

encrypting packets identified as being of the specified packet type using a first encryption method to produce first encrypted packets; and

replacing the unencrypted packets of the specified packet type with the first encrypted packets in the digital video signal to produce a partially encrypted video signal.

10. The method according to claim 9, wherein the encrypting comprises encrypting packets containing slice headers for the N consecutive slices.

11. The method according to claim 9, wherein the encrypting comprises encrypting packets containing intra-coded macroblocks in the N consecutive slices.

12. The method according to claim 9, wherein the at least one specified packet type further comprises packets containing data from a first macroblock following the video slice header in the N consecutive slices.

13. The method according to claim 9, wherein N is between 1 and 10.

16. An electronic transmission medium carrying an encrypted digital video signal encrypted by the method according to claim 9.

17. A selective encryption encoder, comprising:

a packet identifier that identifies packets of at least one specified packet type;

a packet duplicator that duplicates the identified packets to produce first and second sets of the identified packets;

means for sending and receiving packets to and from a primary encryption encoder to encrypt the first set of identified packets under a first encryption method;

a secondary encrypter for encrypting the second set of identified packets under a second encryption method; and

wherein the packet identifier identifies packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices.

18. The selective encryption encoder according to claim 17, wherein the at least one specified packet type comprises packets containing slice headers for the N consecutive slices.

19. The selective encryption encoder according to claim 17, wherein the at least one specified packet type comprises packets containing intra-coded macroblocks in the N consecutive slices.

20. The selective encryption encoder according to claim 17, wherein the at least one specified packet type further comprises packets containing data from a first macroblock following the video slice header in the N consecutive slices.

21. The method according to claim 17, wherein N is between 1 and 10.

22. A television set-top box, comprising:

a receiver receiving a digital television signal comprising;

a plurality of unencrypted packets; and

a plurality of encrypted packets, wherein the encrypted packets are of at least one selected packet type and the at least one specified packet type comprising packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices;

a decrypter that decrypts the encrypted packets; and

a decoder that decodes the unencrypted packets and the decrypted packets to produce a signal suitable for play on a television set.

23. The method according to claim 22, wherein N is between 1 and 10.

24. A selective encryption decoder, for decrypting and decoding a selectively encrypted digital video signal, comprising:

a demultiplexer that receives packets of digital video, certain of the packets being unencrypted and certain of the packets being encrypted, wherein certain of the encrypted packets comprise packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices;

the unencrypted packets having a first packet identifier (PID) and the encrypted packets having a second packet identifier (PID);

a decrypter receiving the encrypted packets having the second PID and decrypting the encrypted packets using a first encryption method to produce decrypted packets;

a PID remapper that changes at least one of the first and second PIDs so that the unencrypted packets and the decrypted packets have the same PID; and

a decoder that decodes the unencrypted and decrypted packets to produce a decoded video signal.

25. The method according to claim 24, wherein N is between 1 and 10.

26. A method of decrypting and decoding a selectively encrypted digital video signal, comprising:

receiving packets of digital video, certain of the packets being unencrypted and certain of the packets being encrypted, wherein certain of the encrypted packets comprise packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices;

the unencrypted packets having a first packet identifier (PID) and the encrypted packets having a second packet identifier (PID);

decrypting the encrypted packets having the second PID to produce decrypted packets;

remapping at least one of the first and second PIDs so that the unencrypted packets and the decrypted packets have the same PID; and

decoding the unencrypted and decrypted packets to produce a decoded video signal.

27. A computer readable medium carrying instructions which, when executed on a programmed processor, carry out the method of decoding and decrypting a digital video signal according to claim 26.

28. The computer readable medium of claim 27, wherein the medium comprises one of an electronic storage medium and a carrier wave.

29. An electronic transmission medium carrying a digital video signal decoded and decrypted by the method according to claim 26.

30. The method according to claim 26, wherein N is between 1 and 10.

31. A computer readable medium that carries instructions that when executed on a programmed processor to facilitate operation of a video receiver device to decrypt and decode a selectively encoded digital video signal wherein the instructions comprise:

a code segment that controls a demultiplexer that receives packets of digital video, certain of the packets being unencrypted and certain of the packets being encrypted, wherein certain of the encrypted packets comprise packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices, the unencrypted packets having a first packet identifier (PID) and the encrypted packets having a second packet identifier (PID);

a code segment that controls decryption of the encrypted packets to produce decrypted packets;

a code segment that controls remapping at least one of the first and second PIDs so that the unencrypted packets and the decrypted packets have the same PID; and

a code segment that controls decoding the unencrypted and decrypted packets to produce a decoded video signal.

32. The computer readable medium of claim 31, wherein the medium comprises one of an electronic storage medium and a carrier wave.

34. A selectively encrypted digital video signal embodied in a carrier wave, comprising:

a stream of packets of video data, wherein the stream of packets when not encrypted represent a segment of video content;

certain of the packets being unencrypted and certain of the packets being encrypted, wherein certain of the encrypted packets comprise packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices;

a first segment of code that identifies the unencrypted packets by a first packet identifier (PID); and

a second segment of code that identifies the encrypted packets by a second packet identifier (PID).

35. The method according to claim 34, wherein N is between 1 and 10.

36. A selectively encrypted digital video signal embodied in a computer readable medium, comprising:

a sequence of packets of video data, wherein the sequence of packets when not encrypted represent a segment of video content;

wherein certain of the packets are unencrypted;

wherein certain of the packets have been produced by decrypting encrypted packets;

wherein certain of the decrypted packets comprise packets in a set of N consecutive slices in a frame wherein the a second byte after a slice start code is identical in all N consecutive slices; and

a segment of code that identifies the unencrypted packets by a first packet identifier (PID); and

a segment of code that identifies the encrypted packets by a second packet identifier (PID).

37. The method according to claim 36, wherein N is between 1 and 10.

38. A method of detecting intra-coded slices in a progressive refresh frame of video data, comprising:

reading a macroblock byte value in a plurality of adjacent slices of a frame of video data;

comparing the macroblock byte values in a the plurality of adjacent slices; and

determining that the adjacent slices are intra-coded slices if the macroblock byte values are the same in the plurality of adjacent slices.

39. The method according to claim 38, embodied in a synchronous state machine.

40. The method according to claim 38, wherein the plurality of adjacent slices comprises N adjacent slices.

41. The method according to claim 38, wherein the macroblock byte value comprises a second byte after a slice start code.

42. The method according to claim 38, further comprising:

duplicating the intra-coded slices to create duplicate intra-coded slices; and

dual encrypting the duplicate intra-coded slices under first and second encryption methods.

43. The method according to claim 42, wherein the dual encrypting comprises dual encrypting packets containing slice headers intra-coded slices.

44. The method according to claim 42, wherein the dual encrypting comprises dual encrypting packets containing intra-coded macroblocks intra-coded slices.

45. The method according to claim 42, wherein the dual encrypting comprises dual encrypting packets containing data from a first macroblock following the video slice header in the intra-coded slices.

46. The method according to claim 38, further comprising encrypting the intra-coded slices.

47. The method according to claim 46, wherein the encrypting comprises encrypting packets containing slice headers intra-coded slices.

48. The method according to claim 46, wherein the encrypting comprises encrypting packets containing intra-coded macroblocks intra-coded slices.

49. The method according to claim 46, wherein the encrypting comprises encrypting packets containing data from a first macroblock following the video slice header in the intra-coded slices.

50. The method according to claim 38, wherein N is between 1 and 10.

51. A computer readable medium storing instructions which, when executed on a programmed processor, carry out the method of encrypting a digital video signal according to claim 38.

52. The computer readable medium of claim 51, wherein the medium comprises one of an electronic storage medium and a carrier wave.

53. An electronic transmission medium carrying an encrypted digital video signal encrypted by the method according to claim 38.

54. A method of detecting intra-coded slices in a progressive refresh frame of video data, comprising:

reading a second byte following a slice start code in a plurality of adjacent slices of a frame of video data;

comparing the second byte following the slice start code values in N adjacent slices; and

determining that the N adjacent slices are intra-coded slices if the values are the same in the N adjacent slices.

55. The method according to claim 54, embodied in a synchronous state machine.

56. The method according to claim 54, wherein N=3.

57. The method according to claim 56, wherein the N adjacent slices begin with slice number 1, 4, 7, . . . , 28 in a thirty slice frame.

58. The method according to claim 54, further comprising:

duplicating the intra-coded slices to create duplicate intra-coded slices; and

dual encrypting the duplicate intra-coded slices under first and second encryption methods.

59. The method according to claim 54, further comprising encrypting the intra-coded slices.

60. The method according to claim 54, wherein N is between 1 and 10.