Reconstitution of program streams split across multiple program identifiers

• US 20020194613A1
• Filed: 02/27/2002
• Published: 12/19/2002
• Est. Priority Date: 06/06/2001
• 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: Unger, Robert Allan
• Granted Patent: US 7,895,616 B2
• Time in Patent Office: Days
• US Class Current: 725/118
• 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 21/25875 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 21/4344 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 21/43607 Interfacing a plurality of external cards, e.g. through a DVB Common Interface [DVB-CI]
• CPC Class Codes: H04N 21/43853 involving multiplex stream decryption arrangements using cryptography for the use of broadcast information or broadcast-related information H04H60/23
• 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 method and apparatus for reconstituting packetized data streams representing a television program when the program uses multiple packet identifiers (PID) as in selective encryption schemes. Transmission of multiple sets of system information (SI) is avoided by incorporating a lookup table within a private data packet. A dual buffer arrangement in the set-top box provides ease of reconstitution of a data stream by generation of an interrupt upon receipt of a packet with a shadow PID. The buffers are toggled as a result of the interrupt and a corresponding packet can be found either at the beginning of the newly active buffer or the end of the inactive buffer. The stream of packets representing a program can then be reconstituted by creation of a new packet having the primary PID and shadow packet'"'"'s payload.

Claims

1. A method of providing multiple program identifier (PID) information for a multiple carriage content delivery system, comprising:

constructing a program association table (PAT) that associates programs with primary PIDs;

constructing a plurality of program map tables (PMT), one for each program in the PAT;

constructing a lookup table that maps at least one primary PID to at least one shadow PID; and

broadcasting the PAT, the PMTs and the lookup table over the content delivery medium.

2. The method according to claim 1, wherein the lookup table is broadcast as one or more MPEG user private data packets.

3. The method according to claim 1, carried out at a cable television system headend.

4. A method of demultiplexing a data stream having multiple program identifiers for a program, comprising:

receiving a program association table (PAT) that associates programs with primary PIDs;

receiving a program map table (PMT);

receiving a lookup table relating primary PIDs to shadow PIDs;

determining, from the PMT and the lookup table that a program is associated with both a primary PID and a shadow PID; and

setting a PID filter to permit passage of packets having both primary and shadow PIDs.

5. The method according to claim 4, further comprising establishing a demultiplexer output path for both the primary PID and the shadow PID.

6. The method according to claim 4, wherein the lookup table contains a shadow PID for a shadow entitlement control message (ECM), and further comprising initializing a decrypter using the shadow ECM.

7. The method according to claim 4, carried out in a television set-top box.

8. A method of constructing a stream of data packets having primary and shadow packet identifiers (PIDs), the packets having headers and payloads, comprising:

receiving an incoming data stream having packets with the primary and shadow PIDs;

providing a stream of packets having the primary PID to a first buffer;

detecting a packet having the shadow PID and a shadow payload in the incoming data stream;

switching the stream of packets having the primary PID to a second buffer in response to the detecting; and

searching a last packet stored in the first buffer for a packet corresponding to the packet having the shadow PID.

9. The method according to claim 8, further comprising generating an interrupt as a result of detecting the packet having the shadow PID.

10. The method according to claim 9, wherein the switching is carried out in response to the interrupt.

11. The method according to claim 8, further comprising generating a packet having the primary PID and the shadow payload.

12. The method according to claim 11, wherein the generating comprises substituting the primary PID for the shadow PID into the packet having the shadow PID.

13. The method according to claim 11, wherein the generating comprises substituting the shadow payload into the matching packet.

14. The method according to claim 8, wherein the corresponding packets have the matching sequence number.

15. The method according to claim 8, wherein the corresponding packets are encrypted under two different encryption techniques.

16. A storage medium storing instructions which, when executed on a programmed processor, carry out a process according to claim 8.

18. The method according to claim 17, further comprising generating an interrupt as a result of detecting the packet having the shadow PID.

19. The method according to claim 18, wherein the switching is carried out in response to the interrupt.

20. The method according to claim 17, further comprising generating a packet having the primary PID and the shadow payload.

21. The method according to claim 20, wherein the generating comprises substituting the primary PID for the shadow PID into the packet having the shadow PID.

22. The method according to claim 20, wherein the generating comprises substituting the shadow payload into the matching packet.

23. The method according to claim 17, wherein the corresponding packets have the matching sequence number.

24. The method according to claim 17, wherein the corresponding packets are encrypted under two different encryption techniques.

25. An electronic storage medium storing instructions which, when executed on a programmed processor, carry out a process according to claim 17.

27. The method according to claim 26, further comprising generating an interrupt as a result of detecting the packet having the shadow PID.

28. The method according to claim 27, wherein the switching is carried out in response to the interrupt.

29. The method according to claim 26, further comprising generating a packet having the primary PID and the shadow payload.

30. The method according to claim 29, wherein the generating comprises substituting the primary PID for the shadow PID into the packet having the shadow PID.

31. The method according to claim 29, wherein the generating comprises substituting the shadow payload into the matching packet.

32. The method according to claim 26, wherein the corresponding packets have the matching sequence number.

33. The method according to claim 26, wherein the corresponding packets are encrypted under two different encryption techniques.

34. An electronic storage medium storing instructions which, when executed on a programmed processor, carry out a process according to claim 26.

36. The method according to claim 35, further comprising generating an interrupt as a result of detecting the packet having the shadow PID.

37. The method according to claim 36, wherein the determining is carried out in response to the interrupt and wherein the determining comprises storing contents of a DMA register to note temporal location for packets.

38. The method according to claim 35, further comprising generating a packet having the primary PID and the shadow payload.

39. The method according to claim 38, wherein the generating comprises substituting the primary PID for the shadow PID into the packet having the shadow PID.

40. The method according to claim 38, wherein the generating comprises substituting the shadow payload into the matching packet.

41. The method according to claim 35, wherein the corresponding packets have the matching sequence number.

42. The method according to claim 35, wherein the corresponding packets are encrypted under two different encryption techniques.

43. An electronic storage medium storing instructions which, when executed on a programmed processor, carry out a process according to claim 35.

17. A method of constructing a stream of data packets having primary and shadow packet identifiers (PIDs), the packets having headers and payloads, comprising:

receiving an incoming data stream having packets with the primary and shadow PIDs;

providing a stream of packets having the primary PID to a first buffer;

detecting a packet having the shadow PID and a shadow payload in the incoming data stream;

switching the stream of packets having the primary PID to a second buffer in response to the detecting; and

searching a first packet stored in the second buffer for a packet corresponding to the packet having the shadow PID.

26. A method of constructing a stream of data packets having primary and shadow packet identifiers (PIDs), the packets having headers and payloads, comprising:

receiving an incoming data stream having packets with the primary and shadow PIDs;

providing a stream of packets having the primary PID to a first buffer;

detecting a packet having the shadow PID and a shadow payload in the incoming data stream;

switching the stream of packets having the primary PID to a second buffer in response to the detecting; and

searching a first packet stored in the second buffer and a last packet stored in the first buffer for a packet corresponding to the packet having the shadow PID.

35. A method of constructing a stream of data packets having primary and shadow packet identifiers (PIDs), the packets having headers and payloads, comprising:

receiving an incoming data stream having packets with the primary and shadow PIDs;

providing a stream of packets having the primary PID to a first buffer;

detecting a packet having the shadow PID and a shadow payload in the incoming data stream;

switching the stream of packets having the primary PID to a second buffer in response to the detecting;

determining a memory address for a storage location in the first buffer at a time of the detecting; and

searching for a packet stored at approximately the memory address in the first buffer for a packet corresponding to the packet having the shadow PID.

44. A digital television receiver apparatus that reconstitutes/reconstructs a stream of data packets having primary and shadow packet identifiers (PIDs), the packets having headers and payloads, the receiver comprising:

a micro computer;

a first primary packet buffer;

a second primary packet buffer;

a demultiplexer receiving an incoming data stream having packets with the primary and shadow PIDs and providing a stream of packets having the primary PID to one of the toggled primary packet buffers;

means for detecting a packet having the shadow PID and a shadow payload in the incoming data stream;

an interrupt handler that generates an interrupt as a result of detecting the packet having the shadow PID;

means for togging the stream of packets having the primary PID to the other of the first and second primary packet buffers in response to the interrupt; and

program means running on the microcomputer for identifying a location of a packet adjacent the detected packet at least one of the first and second primary packet buffers.

45. The apparatus according to claim 44, further comprising program means running on the micro computer for generating a packet having the primary PID and the shadow payload.

46. The apparatus according to claim 45, wherein the generating comprises substituting the primary PID for the shadow PID into the packet having the shadow PID.

47. The apparatus according to claim 45, wherein the generating comprises substituting the shadow payload into the matching packet.

48. The apparatus according to claim 44 wherein the corresponding packets have the matching sequence number.

49. The apparatus according to claim 44, wherein the corresponding packets are encrypted under two different encryption techniques.

50. The apparatus according to claim 44, wherein the program means comprises means for reading a DMA register.

51. The apparatus according to claim 44, wherein the digital television receiver device comprises a television set-top box.