System and method for processing conditional access data

• US 20020116705A1
• Filed: 02/20/2001
• Published: 08/22/2002
• Est. Priority Date: 02/20/2001
• Status: Abandoned Application

• Current Assignee: Diego
• Original Assignee: Diego
• Inventors: Perlman, Stephen G., Sleator, Michael
• Application Number:
  US09/790,076
• Publication Number:
  US 20020116705A1
• Time in Patent Office: Days
• US Class Current: 725/31
• CPC Class Codes: H04N 2005/91364 the video signal being scrambled
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/4147 PVR [Personal Video Recorder] H04N5/76 takes precedence ; arrangements for broadcast with accumulation-type receivers H04H20/40
• CPC Class Codes: H04N 21/426 Internal components of the client ; Characteristics thereof H04N5/44 takes precedence
• CPC Class Codes: H04N 21/4325 by playing back content from the storage medium reproduction of recorded television signals H04N5/76; reproduction of recorded television signals H04N9/79
• 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 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/44222 Analytics of user selections, e.g. selection of programs or purchase activity monitoring of user selections in data processing systems G06F11/34; arrangements for monitoring the user's behaviour or opinions in broadcast systems H04H60/33
• CPC Class Codes: H04N 21/4532 involving end-user characteristics, e.g. viewer profile, preferences monitoring of user activities for profile generation for accessing a video database G06F16/739; user profiles in network data switching protocols H04L67/306; processing of user preferences or user profiles in wireless networks H04W8/18
• CPC Class Codes: H04N 21/454 Content or additional data filtering, e.g. blocking advertisements
• CPC Class Codes: H04N 21/4622 Retrieving content or additional data from different sources, e.g. from a broadcast channel and the Internet web site content organization and management for information retrieval from the Internet G06F16/958; transmission by internet of broadcast information H04H60/82; stock exchange data over packet-switching network H04L12/1804; push services including data channel over packet-switching network H04L12/1859
• CPC Class Codes: H04N 21/47 End-user applications
• CPC Class Codes: H04N 21/4782 Web browsing , e.g. WebTV
• CPC Class Codes: H04N 21/84 Generation or processing of descriptive data, e.g. content descriptors systems specially adapted for using meta-information in broadcast systems H04H60/73
• 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 21/8586 by using a URL processing chained hypermedia data for information retrieval G06F16/94; information retrieval from the Internet by using URLs G06F16/955; URL in broadcast information H04H20/93; Web-based protocols H04L67/02
• CPC Class Codes: H04N 5/76 Television signal recording
• CPC Class Codes: H04N 5/781 on disks or drums
• 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 7/165 : 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 7/17318 : Direct or substantially direct transmission and handling of requests
• CPC Class Codes: H04N 9/8042 : involving data reduction
• CPC Class Codes: H04N 9/8205 : involving the multiplexing of an additional signal and the colour video signal

Abstract

A computer-implemented method is disclosed comprising: storing a first encrypted multimedia stream on a storage device as the stream is broadcast by a content provider; storing a stream of conditional access data on the storage device, the stream of conditional access data associated with the multimedia stream; and decrypting the first encrypted multimedia stream from a specified point within the encrypted multimedia stream using the stream of conditional access data, responsive to a user request to play back the encrypted multimedia stream from the specified point.

Claims

1. A computer-implemented method comprising:

storing a first encrypted multimedia stream on a storage device as said stream is broadcast by a content provider;

storing a stream of conditional access data on said storage device, said stream of conditional access data associated with said multimedia stream; and

decrypting said first encrypted multimedia stream from a specified point within said encrypted multimedia stream using said stream of conditional access data, responsive to a user request to play back said encrypted multimedia stream from said specified point.

2. The computer-implemented method as in claim 1 wherein decrypting further comprising:

reading conditional access data from said stream of conditional access data from said specified point concurrently with reading said first encrypted multimedia stream from said specified point, said conditional access data identifying successive keys for decrypting corresponding successive portions of said first encrypted multimedia stream.

3. The method as in claim 2 further comprising:

providing said successive keys identified by said conditional access data to a conditional access module wherein said conditional access module uses said successive keys to decrypt corresponding successive portions of said first encrypted multimedia stream to produce a first decrypted multimedia stream.

4. The method as in claim 3 further comprising:

decoding said first decrypted multimedia stream using a specified codec.

5. The method as in claim 4 wherein said specified codec is MPEG-2.

6. The method as in claim 2 wherein a secure micro unit provides said successive keys to said conditional access module responsive to reading said conditional access data.

7. The method as in claim 1 further comprising:

storing a second encrypted multimedia stream on said storage device at the same time as said first encrypted multimedia stream is stored to said storage device, wherein said stream of conditional access data contains conditional access data associated with said second encrypted multimedia stream as well as said first multimedia stream;

decrypting said second encrypted multimedia stream using said stream of conditional access data responsive to a user request to play back said second encrypted multimedia stream from a specified point within said second encrypted multimedia stream.

8. The method as in claim 7 wherein said first and second multimedia streams are stored on said storage device in a multiplexed format.

9. The method as in claim 8 wherein said multiplexed format comprises a series of packets containing multimedia data for said first and second multimedia streams.

10. The method as in claim 1 further comprising:

performing a lookup in a timestamp index using a specified point in time to identify said specified point within said first encrypted multimedia stream to begin decrypting.

11. The method as in claim 10 wherein said timestamp index is comprised of a set of timestamps and corresponding address pointers, said address pointers identifying said specified point within said first encrypted multimedia stream from which to begin decryption.

12. The method as in claim 10 wherein said timestamp index is transmitted by said content provider.

13. The method as in claim 11 wherein said address pointers point to I-frames within said multimedia stream.

14. The method as in claim 10 further comprising:

generating said timestamp index in real time as said first encrypted multimedia stream is received.

15. The method as in claim 14 further comprising:

identifying an I-frame within said first encrypted multimedia stream by decrypting said first encrypted multimedia stream from said specified point in time until an I-frame is reached.

16. The method as in claim 15 further comprising:

decrypting and decoding said I-frame as well as any B and P frames following said I-frame; and

rendering said multimedia stream on a display beginning with said I-frame.

18. The apparatus as in claim 17 further comprising:

a conditional access module to decrypt said first encrypted multimedia stream using said first subset of conditional access data.

19. The apparatus as in claim 17 further comprising:

a secure micro unit to read said first subset of conditional access data and identify a series of decryption keys responsive thereto; and

a conditional access module to use said series of decryption keys to decrypt said first encrypted multimedia stream from said specified point within said encrypted multimedia stream.

20. The apparatus as in claim 17 wherein said mass storage device stores a second encrypted multimedia stream and wherein said selection logic identifies a second subset of said conditional access data to be used to decrypt said second encrypted multimedia stream from a specified point within said second encrypted multimedia stream.

21. The apparatus as in claim 20 further comprising:

a conditional access module to decrypt said first and second encrypted multimedia streams using said first and second subsets of conditional access data, respectively.

22. The apparatus as in claim 21 further comprising:

a secure micro unit to read said first and second subsets of conditional access data and identify a first and second series of decryption keys responsive thereto; and

a conditional access module to use said first and second series of decryption keys to decrypt said first and second encrypted multimedia streams from said specified points within said first and second encrypted multimedia stream.

23. The apparatus as in claim 20 further comprising

a multi-stream PID filter module to demultiplex said first multimedia stream from said second multimedia stream prior to rendering said first multimedia stream on said display.

24. The apparatus as in claim 23 wherein said multi-stream PID filter demultiplexes said first multimedia stream from said second multimedia stream prior to storing said first and second multimedia streams on said storage device.

25. The apparatus as in claim 17 further comprising:

a timestamp index used by said selection logic to identify said first specified point within said first encrypted multimedia stream to begin decrypting.

26. The apparatus as in claim 25 wherein said timestamp index is comprised of a set of timestamps and corresponding address pointers, said address pointers identifying said first specified point within said first encrypted multimedia stream from which to begin decryption.

27. The apparatus as in claim 25 wherein said timestamp index is transmitted by said content provider.

28. The apparatus as in claim 26 wherein said address pointers point to I-frames within said multimedia stream.

29. The apparatus as in claim 25 further comprising:

timestamp index generation logic to generate said timestamp index in real time as said first encrypted multimedia stream is received from a content provider.

30. The apparatus as in claim 29 further comprising:

I-frame identification logic to identify an I-frame within said first encrypted multimedia stream by decrypting said first encrypted multimedia stream from said specified point in time until an I-frame is reached.

31. The apparatus as in claim 30 wherein once said I-frame identification logic identifies said I-frame, said conditional access module decrypts said first encrypted multimedia stream from said I-frame onward, said apparatus further comprising:

a decoder for decoding said first encrypted multimedia stream from said I-frame onward; and

a display for rendering said first encrypted multimedia stream.

17. An apparatus for processing multimedia streams and conditional access data comprising:

a mass storage device to store a first encrypted multimedia stream and associated conditional access data; and

selection logic to identify a first subset of said conditional access data to be used to decrypt said first encrypted multimedia stream from a specified point within said first encrypted multimedia stream.

32. An article of manufacture including a sequence of instructions which, when executed by a machine, cause said machine to perform the operations of:

storing a first encrypted multimedia stream on a storage device as said stream is broadcast by a content provider;

storing a stream of conditional access data on said storage device, said stream of conditional access data associated with said multimedia stream; and

decrypting said first encrypted multimedia stream from a specified point within said encrypted multimedia stream using said stream of conditional access data, responsive to a user request to play back said encrypted multimedia stream from said specified point.

33. The article of manufacture as in claim 32 wherein decrypting further comprising:

reading conditional access data from said stream of conditional access data from said specified point concurrently with reading said first encrypted multimedia stream from said specified point, said conditional access data identifying successive keys for decrypting corresponding successive portions of said first encrypted multimedia stream.

34. The article of manufacture as in claim 33 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

providing said successive keys identified by said conditional access data to a conditional access module wherein said conditional access module uses said successive keys to decrypt corresponding successive portions of said first encrypted multimedia stream to produce a first decrypted multimedia stream.

35. The article of manufacture as in claim 34 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

;

decoding said first decrypted multimedia stream using a specified codec.

36. The article of manufacture as in claim 35 wherein said specified codec is MPEG-2.

37. The article of manufacture as in claim 33 wherein a secure micro unit provides said successive keys to said conditional access module responsive to reading said conditional access data.

38. The article of manufacture as in claim 32 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

storing a second encrypted multimedia stream on said storage device at the same time as said first encrypted multimedia stream is stored to said storage device, wherein said stream of conditional access data contains conditional access data associated with said second encrypted multimedia stream as well as said first multimedia stream;

decrypting said second encrypted multimedia stream using said stream of conditional access data responsive to a user request to play back said second encrypted multimedia stream from a specified point within said second encrypted multimedia stream.

39. The article of manufacture as in claim 38 wherein said first and second multimedia streams are stored on said storage device in a multiplexed format.

40. The article of manufacture as in claim 39 wherein said multiplexed format comprises a series of packets containing multimedia data for said first and second multimedia streams.

41. The article of manufacture as in claim 32 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

performing a lookup in a timestamp index using a specified point in time to identify said specified point within said first encrypted multimedia stream to begin decrypting.

42. The article of manufacture as in claim 41 wherein said timestamp index is comprised of a set of timestamps and corresponding address pointers, said address pointers identifying said specified point within said first encrypted multimedia stream from which to begin decryption.

43. The article of manufacture as in claim 41 wherein said timestamp index is transmitted by said content provider.

44. The article of manufacture as in claim 42 wherein said address pointers point to I-frames within said multimedia stream.

45. The article of manufacture as in claim 41 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

generating said timestamp index in real time as said first encrypted multimedia stream is received.

46. The article of manufacture as in claim 45 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

identifying an I-frame within said first encrypted multimedia stream by decrypting said first encrypted multimedia stream from said specified point in time until an I-frame is reached.

47. The article of manufacture as in claim 46 including additional instructions which, when executed by said machine, cause said machine to perform the operations of:

decrypting and decoding said I-frame as well as any B and P frames following said I-frame; and

rendering said multimedia stream on a display beginning with said I-frame.

49. The method as in claim 48 further comprising:

generating a timestamp index in real time as said encrypted multimedia stream is being stored on said mass storage device.

50. The method as in claim 48 further comprising:

receiving said timestamp index from a content provider providing said multimedia stream.

51. The method as in claim 48 further comprising:

if said address pointer identifies a point within said encrypted multimedia stream which is not an I-frame,

decrypting said encrypted multimedia stream until an I-frame is reached; and

decrypting, decoding and rendering said encrypted multimedia stream on a display from said I-frame onward.

52. The method as in claim 48 further comprising:

receiving a request to fast-forward through said encrypted multimedia stream; and

decrypting, decoding and displaying a series of I-frames in succession in response to said fast-forward request, said I-frames being decrypted, decoded and displayed at a rate based on a selected speed of said fast-forward request.

53. The method as in claim 52 wherein said I-frames are identified by estimating a location of a next successive I-frame;

jumping to said estimated location;

decoding said decrypted multimedia stream from said location onward until said next successive I-frame is reached; and

decrypting, decoding and displaying said next successive I-frame.

54. The method as in claim 52 further comprising:

decrypting I-frames as quickly as decryption keys can be generated if said selected speed of said fast forward request exceeds a maximum speed at which said decryption keys can be generated.

55. The method as in claim 52 further comprising:

jumping past one or more successive I-frames before a next I-frame is decrypted.

48. A method comprising:

receiving a request to play back an encrypted multimedia stream stored on a mass storage device, said request including a point in time from which said encrypted multimedia stream is to be played;

performing a lookup in a timestamp index to identify an address pointer identifying a point within said encrypted multimedia stream corresponding to said point in time; and

decrypting said encrypted multimedia stream from said point within said multimedia stream.