Multiple partial encryption using retuning

• US 20040047470A1
• Filed: 10/18/2002
• Published: 03/11/2004
• Est. Priority Date: 09/09/2002
• 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.
• Granted Patent: US 7,242,773 B2
• Time in Patent Office: Days
• US Class Current: 380/240
• CPC Class Codes: H04N 2005/91364 the video signal being scrambled
• CPC Class Codes: H04N 21/234345 the reformatting operation being performed only on part of the stream, e.g. a region of the image or a time segment
• CPC Class Codes: H04N 21/23439 for generating different versions
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/236 Assembling of a multiplex stream, e.g. transport stream, by combining a video stream with other content or additional data, e.g. inserting a URL [Uniform Resource Locator] into a video stream, multiplexing software data into a video stream; Remultiplexing of multiplex streams; Insertion of stuffing bits into the multiplex stream, e.g. to obtain a constant bit-rate; Assembling of a packetised elementary stream multiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• CPC Class Codes: H04N 21/238 Interfacing the downstream path of the transmission network, e.g. adapting the transmission rate of a video stream to network bandwidth; Processing of multiplex streams hybrid fiber coaxial [HFC] networks for downstream channel allocation for video distribution H04L12/2801; flow control in packet networks H04L47/10; real-time communication protocols in data switching networks H04L65/00; scheduling or organising the servicing of application requests H04L67/60
• CPC Class Codes: H04N 21/25435 involving characteristics of content or additional data, e.g. video resolution or the amount of advertising
• CPC Class Codes: H04N 21/25833 involving client hardware characteristics, e.g. manufacturer, processing or storage capabilities allocation of resources considering hardware capabilities in multiprogramming arrangements G06F9/5044; allocation of resources considering software capabilities in multiprogramming arrangements G06F9/5055
• 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 21/2668 Creating a channel for a dedicated end-user group, e.g. insertion of targeted commercials based on end-user profiles information retrieval from the Internet by querying with filtering and personalisation G06F16/9535; arrangements for replacing or switching information during the broadcast H04H20/10; push services over packet-switching network H04L12/1859; adaptation of message content in packet-switching networks H04L51/063
• CPC Class Codes: H04N 21/4331 Caching operations, e.g. of an advertisement for later insertion during playback
• CPC Class Codes: H04N 21/4333 Processing operations in response to a pause request
• CPC Class Codes: H04N 21/434 Disassembling of a multiplex stream, e.g. demultiplexing audio and video streams, extraction of additional data from a video stream; Remultiplexing of multiplex streams; Extraction or processing of SI; Disassembling of packetised elementary stream demultiplexing of data packets for data networks, e.g. RTP/UDP H04L65/00
• 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 21/43607 Interfacing a plurality of external cards, e.g. through a DVB Common Interface [DVB-CI]
• CPC Class Codes: H04N 21/440245 the reformatting operation being performed only on part of the stream, e.g. a region of the image or a time segment
• CPC Class Codes: H04N 21/440281 by altering the temporal resolution, e.g. by frame skipping television signal recording using magnetic recording on tape for reproducing at a rate different from the recording rate H04N5/783
• CPC Class Codes: H04N 21/44055 by partially decrypting, e.g. decrypting a video stream that has been partially encrypted
• CPC Class Codes: H04N 21/458 : Scheduling content for creating a personalised stream, e.g. by combining a locally stored advertisement with an incoming stream; Updating operations, e.g. for OS modules ; time-related management operations arrangements for replacing or switching information during the broadcast or during the distribution H04H20/10
• 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 21/47202 : for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/63345 : by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 21/812 : involving advertisement data advertising per se G06Q30/02
• CPC Class Codes: H04N 21/835 : Generation of protective data, e.g. certificates protecting software against unauthorised usage in a vending or licensing environment G06F21/10
• CPC Class Codes: H04N 21/8455 : involving pointers to the content, e.g. pointers to the I-frames of the video stream
• CPC Class Codes: H04N 5/783 : Adaptations for reproducing at a rate different from the recording rate
• CPC Class Codes: H04N 5/913 : for scrambling ; for copy protection
• CPC Class Codes: H04N 7/163 : by receiver means only
• CPC Class Codes: H04N 7/165 : Centralised control of user terminal subsequent to an upstream request signal H04N7/17345; Registering at central by two-way working H04N7/17309
• 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
• CPC Class Codes: H04N 7/52 : Systems for transmission of a pulse code modulated video signal with one or more other pulse code modulated signals, e.g. an audio signal or a synchronizing signal assembling of a multiplex stream by combining a video stream with other content or additional data, remultiplexing of multiplex streams, insertion of stuffing bits into the multiplex stream, assembling of a packetised elementary stream at server side H04N21/236; disassembling of a multiplex stream, remultiplexing of multiplex streams, extraction or processing of Service Information, disassembling of packetised elementary stream at client side H04N21/434
• CPC Class Codes: H04N 9/7925 : for more than one standard

Abstract

A partial dual encryption encoder, consistent with certain embodiments of the present invention receives video from a source of an unencrypted digital video signal. A first segment of the unencrypted digital video signal is selected for transmission over a first channel. A first encrypter encrypts a second segment of the unencrypted digital video signal under a first encryption method to produce a first encrypted segment and a second encrypter that encrypts the second segment of the unencrypted digital video signal under a second encryption to produce a second encrypted segment. A multiplexer combines the unencrypted digital video signal with the first and second encrypted segments for transmission, so that the first segment is transmitted over a first channel, the first encrypted segment is transmitted over the first channel and the second encrypted segment is transmitted over a second channel. A trigger message generator generates a trigger message indicating that the second encrypted segment of the digital video signal will be encrypted and will be transmitted on a second channel. The multiplexer further combines the trigger message with the first segment, the first encrypted segment and second encrypted segment.

Claims

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

transmitting a first segment of the digital video signal as an unencrypted digital video signal using a first channel;

transmitting a trigger message indicating that a second segment of the digital video signal will be encrypted and will appear on a second channel;

duplicating the second segment to produce first and second copies of the second segment;

encrypting the first copy of the second segment under a first encryption method to produce a first encrypted segment;

encrypting the second copy of the second segment under a second encryption method to produce a second encrypted segment;

transmitting the first encrypted segment over the first channel; and

transmitting the second encrypted segment over the second channel.

2. The method according to claim 1, wherein the first channel is associated with a first packet identifier (PID) and the second channel is associated with a second packet identifier.

3. The method according to claim 1, wherein the first channel is associated with a first frequency and the second channel is associated with a second frequency.

4. The method according to claim 1, wherein the trigger message comprises a part of a program specific information (PSI) message.

5. The method according to claim 4, wherein the trigger message is encoded as user specific information within the PSI message.

6. The method according to claim 1, wherein the trigger message contains a starting time for the second segment of digital video signal.

7. The method according to claim 1, wherein the trigger message contains a starting packet number for the second segment of digital video signal.

8. The method according to claim 1, further comprising transmitting segments of unencrypted digital video alternating with duplicated segments of encrypted digital video, with the duplicated encrypted digital video being encrypted under the first and second encryption methods.

9. The method according to claim 8, wherein each of the duplicated encrypted digital video comprises between approximately 10% and 35% of the total digital video signal.

10. The method according to claim 1, further comprising transmitting a second trigger message indicating that a third segment of the digital video signal will be unencrypted and will appear on a specified channel.

11. The method according to claim 10, wherein the specified channel comprises the first channel.

12. The method according to claim 10, wherein the specified channel comprises a third channel.

13. 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.

14. The computer readable medium of claim 13, wherein the medium comprises one of an electronic storage medium and a carrier wave.

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

16. A partial dual encryption encoder, comprising:

a source of an unencrypted digital video signal;

means for selecting a first segment of the unencrypted digital video signal for transmission over a first channel;

a first encrypter that encrypts a second segment of the unencrypted digital video signal under a first encryption method to produce a first encrypted segment;

a second encrypter that encrypts the second segment of the unencrypted digital video signal under a second encryption to produce a second encrypted segment;

a multiplexer that combines the unencrypted digital video signal with the first and second encrypted segments for transmission, so that the first segment is transmitted over a first channel, the first encrypted segment is transmitted over the first channel and the second encrypted segment is transmitted over a second channel;

a trigger message generator that generates a trigger message indicating that the second encrypted segment of the digital video signal will be encrypted and will be transmitted on a second channel; and

wherein, the multiplexer further combines the trigger message with the first segment, the first encrypted segment and second encrypted segment.

17. The partial dual encryption encoder according to claim 16, wherein the first channel is associated with a first packet identifier (PID) and the second channel is associated with a second packet identifier.

18. The partial dual encryption encoder according to claim 16, wherein the first channel is associated with a first frequency and the second channel is associated with a second frequency.

19. The partial dual encryption encoder according to claim 16, wherein the trigger message comprises a part of a program specific information (PSI) message.

20. The partial dual encryption encoder according to claim 19, wherein the trigger message is encoded as user specific information within the PSI message.

21. The partial dual encryption encoder according to claim 16, wherein the trigger message contains a starting time for the second segment of digital video signal.

22. The partial dual encryption encoder according to claim 16, wherein the trigger message contains a starting packet number for the second segment of digital video signal.

23. The partial dual encryption encoder according to claim 16, further comprising transmitting segments of unencrypted digital video alternating with duplicated segments of encrypted digital video, with the duplicated encrypted digital video being encrypted under the first and second encryption methods.

24. The partial dual encryption encoder according to claim 23, wherein each of the duplicated encrypted digital video comprises between approximately 10% and 35% of the total digital video signal.

25. The partial dual encryption encoder according to claim 16, further comprising transmitting a second trigger message indicating that a third segment of the digital video signal will be unencrypted and will appear on a specified channel.

26. The partial dual encryption encoder according to claim 25, wherein the specified channel comprises the first channel.

27. The partial dual encryption encoder according to claim 25, wherein the specified channel comprises a third channel.

28. A method of partially encrypting an unencrypted digital video signal, comprising:

transmitting a first segment of the digital video signal as an unencrypted digital video signal over a first channel;

transmitting a trigger message indicating that a second segment of the digital video signal will be encrypted;

encrypting the second segment of the digital video signal to produce an second encrypted segment; and

transmitting the second encrypted segment over a second channel.

29. The method according to claim 28, wherein the first channel is associated with a first packet identifier (PID) and the second channel is associated with a second packet identifier.

30. The method according to claim 28, wherein the first channel is associated with a first frequency and the second channel is associated with a second frequency.

31. The method according to claim 28, wherein the trigger message comprises a part of a program specific information (PSI) message.

32. The method according to claim 31, wherein the trigger message is encoded as user specific information within the PSI message.

33. The method according to claim 28, wherein the trigger message contains a starting time for the second segment of digital video signal.

34. The method according to claim 28, wherein the trigger message contains a starting packet number for the second segment of digital video signal.

35. The method according to claim 28, further comprising transmitting segments of unencrypted digital video alternating with segments of encrypted digital video.

36. The method according to claim 35, wherein the encrypted digital video comprises between approximately 10% and 35% of the total digital video signal.

37. The method according to claim 28, further comprising transmitting a second trigger message indicating that a third segment of the digital video signal will be unencrypted and will appear on a specified channel.

38. The method according to claim 37, wherein the specified channel comprises the first channel.

39. The method according to claim 37, wherein the specified channel comprises a third channel.

40. 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 28.

41. The computer readable medium of claim 40, wherein the medium comprises one of an electronic storage medium and a carrier wave.

42. An electronic transmission medium carrying an encrypted digital video signal encrypted by the method according to claim 28.

43. A partial encryption encoder;

comprising;

a source of an unencrypted digital video signal;

means for selecting a first segment of the unencrypted digital video signal for transmission over a first channel;

an encrypter that encrypts a second segment of the unencrypted digital video signal under a first encryption method to produce a second encrypted segment;

a multiplexer that combines the unencrypted digital video signal with the second encrypted segment for transmission, so that the first segment is transmitted over a first channel and the second encrypted segment is transmitted over a second channel;

a trigger message generator that generates a trigger message indicating that the second encrypted segment of the digital video signal will be encrypted and will be transmitted on a second channel; and

wherein, the multiplexer further combines the trigger message with the first segment and second encrypted segment.

44. The partial encryption encoder according to claim 43, wherein the first channel is associated with a first packet identifier (PID) and the second channel is associated with a second packet identifier.

45. The partial encryption encoder according to claim 43, wherein the first channel is associated with a first frequency and the second channel is associated with a second frequency.

46. The partial encryption encoder according to claim 43, wherein the trigger message comprises a part of a program specific information (PSI) message.

47. The partial encryption encoder according to claim 46, wherein the trigger message is encoded as user specific information within the PSI message.

48. The partial encryption encoder according to claim 43, wherein the trigger message contains a starting time for the second segment of digital video signal.

49. The partial encryption encoder according to claim 43, wherein the trigger message contains a starting packet number for the second segment of digital video signal.

50. The partial encryption encoder according to claim 43, further comprising transmitting segments of unencrypted digital video alternating with segments of encrypted digital video.

51. The partial encryption encoder according to claim 50, wherein the encrypted digital video comprises between approximately 10% and 35% of the total digital video signal.

52. The partial encryption encoder according to claim 46, further comprising transmitting a second trigger message indicating that a third segment of the digital video signal will be unencrypted and will appear on a specified channel.

53. The partial encryption encoder according to claim 52, wherein the specified channel comprises the first channel.

54. The partial encryption encoder according to claim 52, wherein the specified channel comprises a third channel.

55. A method of decrypting a partially encrypted digital video signal, comprising:

receiving a first unencrypted segment of the digital video signal as an unencrypted digital video signal over a first channel;

receiving a trigger message indicating that a second segment of the digital video signal will be encrypted and transmitted over a second channel;

tuning to the second channel;

receiving the second encrypted segment over the second channel; and

decrypting the second encrypted segment.

56. The method according to claim 55, wherein the first channel is associated with a first packet identifier (PID) and the second channel is associated with a second packet identifier.

57. The method according to claim 55, wherein the first channel is associated with a first frequency and the second channel is associated with a second frequency.

58. The method according to claim 55, wherein the trigger message comprises a part of a program specific information (PSI) message.

59. The method according to claim 58, wherein the trigger message is encoded as user specific information within the PSI message.

60. The method according to claim 55, wherein the trigger message contains a starting time for the second segment of digital video signal.

61. The method according to claim 55, wherein the trigger message contains a starting packet number for the second segment of digital video signal.

62. The method according to claim 55, further comprising receiving segments of unencrypted digital video alternating with segments of encrypted digital video.

63. The method according to claim 62, wherein the encrypted digital video comprises between approximately 10% and 35% of the total digital video signal.

64. A computer readable medium carrying instructions which, when executed on a programmed processor, carry out the method of decrypting a digital video signal according to claim 55.

65. The computer readable medium of claim 64, wherein the medium comprises one of an electronic storage medium and a carrier wave.

66. An electronic transmission medium carrying a digital video signal decrypted by the method according to claim 55.

67. A partial encryption decoder for decoding and decrypting a partially encrypted digital video signal, comprising:

a receiver that receives a first unencrypted segment of the digital video signal as an unencrypted digital video signal over a first channel and receives a second encrypted segment over a second channel;

a trigger message decoder that receives and decodes a trigger message indicating that a second segment of the digital video signal will be encrypted and transmitted over a second channel, the decoder causing the receiver to tune to the second channel for receipt of the second encrypted segment; and

a decrypter that receives and decrypts the second encrypted segment.

68. The partial encryption decoder according to claim 67, wherein the first channel is associated with a first packet identifier (PID) and the second channel is associated with a second packet identifier.

69. The partial encryption decoder according to claim 67, wherein the first channel is associated with a first frequency and the second channel is associated with a second frequency.

70. The partial encryption decoder according to claim 67, wherein the trigger message comprises a part of a program specific information (PSI) message.

71. The partial encryption decoder according to claim 70, wherein the trigger message is encoded as user specific information within the PSI message.

72. The partial encryption decoder according to claim 67, wherein the trigger message contains a starting time for the second segment of digital video signal.

73. The partial encryption decoder according to claim 67, wherein the trigger message contains a starting packet number for the second segment of digital video signal.

74. The partial encryption decoder according to claim 67, further comprising receiving segments of unencrypted digital video alternating with segments of encrypted digital video.

75. The partial encryption decoder according to claim 74, wherein the encrypted digital video comprises between approximately 10% and 35% of the total digital video signal.

76. A television set-top box, comprising:

a receiver receiving a digital television signal comprising;

a plurality of unencrypted packets received over a first channel; and

a plurality of encrypted packets received over a second channel;

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.

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

a code segment that controls a receiver that receives a first unencrypted segment of the digital video signal as an unencrypted digital video signal over a first channel and receives a second encrypted segment over a second channel;

a code segment that controls a trigger message decoder that receives and decodes a trigger message indicating that a second segment of the digital video signal will be encrypted and transmitted over a second channel, the decoder causing the receiver to tune to the second channel for receipt of the second encrypted segment; and

a code segment that controls a decrypter that receives and decrypts the second encrypted segment.

78. The computer readable medium of claim 77, wherein the medium comprises one of an electronic storage medium and a carrier wave.

79. 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 the encrypted packets are carried on a first channel and the unencrypted packets are carried on a second channel;

a segment of code that identifies the first channel carrying the encrypted packets; and

a second segment of code that identifies the second channel carrying the unencrypted packets.

80. 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 and associated with a first channel;

wherein certain of the packets have been produced by decrypting encrypted packets associated with a second channel; and

a segment of code that identifies the unencrypted packets by a first channel; and

a segment of code that identifies the encrypted packets by a second channel.