System and data format for communicating data between a video decoder and a peripheral device

• US 6,437,830 B1
• Filed: 12/03/1999
• Issued: 08/20/2002
• Est. Priority Date: 05/28/1999
• Status: Expired due to Term

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Thomson Licensing SA (Vantiva SA)
• Inventors: Horlander, Karl Francis
• Primary Examiner(s): Miller, John
• Assistant Examiner(s): Natnael, Paulos M.
• Application Number:
  US09/454,398
• Time in Patent Office: 991 Days
• Field of Search: 348/473, 348/478, 348/476, 348/477, 348/479, 348/460-461, 348/464, 348/465, 348/554, 348/558, 348/434.1, 348/435.1, 386/94, 386/104
• US Class Current: 348/478
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04L 9/40 Network security protocols
• 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 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 21/43615 Interfacing a Home Network, e.g. for connecting the client to a plurality of peripherals home Audio Video Interoperability [HAVI] data switching networks H04L12/2805
• 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 5/765 Interface circuits between an apparatus for recording and another apparatus
• CPC Class Codes: H04N 5/775 between a recording apparatus and a television receiver
• CPC Class Codes: H04N 5/913 for scrambling ; for copy protection
• CPC Class Codes: H04N 5/9206 the additional signal being a character code signal
• CPC Class Codes: H04N 7/035 Circuits for the digital non-picture data signal, e.g. for slicing of the data signal, for regeneration of the data-clock signal, for error detection or correction of the data signal
• CPC Class Codes: H04N 7/088 the inserted signal being digital
• CPC Class Codes: H04N 7/163 by receiver means only
• 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 communication data format conveys digital ancillary data in a vertical blanking interval of a video signal. The format employs a reference symbol including a plurality of digital pulses for indicating the start of the ancillary data and also includes a header byte following the reference symbol. The header byte contains an identifier identifying a destination service for a payload of the ancillary data or an address identifying a destination of the payload. The format also conveys multiple payload bytes, following the reference symbol in which individual bits have a period substantially comprising, a first integral multiple of a first clock period associated with a first data format, and a different second integral multiple of a second clock period associated with a second data format.

Claims

1. A communication data format for conveying digital ancillary data in a vertical blanking interval of a video signal, comprising:

a reference symbol including a plurality of digital pulses for indicating start of said ancillary data;

a header following said reference symbol, containing at least one of, (a) an identifier identifying a destination service for a payload of said ancillary data, and (b) an address identifying a destination of said payload; and

a plurality of payload bytes, following said reference symbol, for conveying said payload wherein individual bits of said ancillary data have a period substantially comprising, a first integral multiple of a first clock period associated with a first data format, and a different second integral multiple of a second clock period associated with a second data format.

2. A data format according to claim 1, wherein

said ancillary data bit period is substantially equal to,

(a) a first integer multiple of a period of a 74.25 MHz clock and

(b) a second integer multiple of a period of an 81 MHz clock.

3. A data format according to claim 2, wherein

said second integer multiple of said period of said 81 MHz clock comprises a period of a 27 MHz+/−

0.5 MHz clock.

4. A data format according to claim 1, wherein

said first and second data formats comprise data formats prescribed by at least two of the following standard definitions (a) EIA-770.1-A, (b) EIA-770.2-A, and (c) EIA-770.3-A.

5. A data format according to claim 1, wherein

said reference symbol starts at a point in a horizontal video line that is substantially coincident with beginning of active video.

6. A data format according to claim 1, wherein

said ancillary data occurs at a rate substantially equal to a horizontally line-locked clock rate to permit recovery of said ancillary data by pulse detection exclusive of prior phase locking.

7. A data format according to claim 1, wherein

said ancillary data may be recovered in a decoder by both,

(a) pulse detection exclusive of prior phase locking, and

(b) pulse detection following prior phase locking using said reference symbol.

8. A data format according to claim 1, wherein

said reference symbol comprises a half a byte “

1010”

bit sequence.

9. A data format according to claim 1, wherein

said header is one byte in length and

said payload bytes comprise two bytes.

10. A data format according to claim 1, wherein

said header comprises,

a 7 bit address field and

a parity bit for detecting errors in at least one of, (a) said header byte, (b) said payload bytes and (c) said header and payload bytes.

11. A data format according to claim 10, wherein

said 7 bit address field comprises one of, (a) a service identifier for identifying a service associated with said payload, (b) a memory address, and (c) a destination identifier for said payload.

12. A data format according to claim 1, wherein

one of said payload bytes conveys, (a) a service identifier for identifying a service associated with said payload, (b) a memory address, and (c) a destination identifier for said payload, and (d) an address extension used in conjunction with an address in said header to jointly identify a destination for said remaining payload data.

13. A method for decoding a communication data format conveying digital ancillary data in a vertical blanking interval of a video signal, comprising the steps of:

identifying a reference symbol including a plurality of digital pulses for indicating start of said ancillary data;

capturing a header following said reference symbol, containing at least one of, (a) an identifier identifying a destination service for a payload of said ancillary data, and (b) an address identifying a destination of said payload; and

capturing a plurality of payload bytes, following said reference symbol, for conveying said payload wherein

said header and payload data are acquired using a horizontally line-locked clock having a period substantially comprising, a first integral multiple of a first clock period associated with a first data format, and a different second integral multiple of a second clock period associated with a second data format.

14. A method according to claim 13, including the step of

acquiring said header and payload data by bit detection using said horizontally line-locked clock exclusively of phase locking.

15. A method according to claim 13, including the steps of

phase locking said ancillary data to a substantially line-locked clock and

detecting data bits in said ancillary data by sampling said data at intervals determined using said substantially line locked clock.

16. A method for forming a communication data format for conveying digital ancillary data in a vertical blanking interval of a video signal, comprising the steps of:

creating a digital data sequence comprising

a reference symbol comprising a “

1010”

bit pattern;

a header following said reference symbol, containing at least one of, (a) an identifier identifying a destination service for a payload of said ancillary data, and (b) an address identifying a destination of said payload; and

a plurality of payload bytes, following said reference symbol, for conveying said payload, wherein individual bits of said ancillary data have a period substantially comprising, a first integral multiple of a first clock period associated with a first data format, and a different second integral multiple of a second clock period associated with a second data format; and

incorporating said digital data sequence within a video waveform vertical blanking interval.

17. A method according to claim 16, wherein

said ancillary data bit period is substantially equal to,

(a) a first integer multiple of a period of a 74.25 MHz clock and

(b) a second integer multiple of a period of an 81 MHz clock.

18. A method according to claim 17, wherein

said second integer multiple of said period of said 81 MHz clock substantially comprises a period of a 27 MHz clock.

19. A method for decoding a communication data format conveying digital ancillary data in a vertical blanking interval of a video signal, comprising the steps of:

identifying a reference symbol comprising a half a byte “

1010”

bit sequence;

capturing a header following said reference symbol, containing at least one of, (a) an identifier identifying a destination service for a payload of said ancillary data, and (b) an address identifying a destination of said payload; and

capturing a plurality of payload bytes conveying said payload, following said reference symbol, wherein

said header and payload data are acquired using a substantially horizontally line-locked clock.