Video coding

• US 7,006,576 B1
• Filed: 07/19/2000
• Issued: 02/28/2006
• Est. Priority Date: 07/19/1999
• Status: Expired due to Term

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Mobile Phones UK Limited (Nokia Corporation)
• Inventors: Hannuksela, Miska
• Primary Examiner(s): DIEP, NHON THANH
• Application Number:
  US09/619,660
• Time in Patent Office: 2,050 Days
• Field of Search: 375/240.27, 375/240.02, 375/240.12, 375/240.18, 375/240.24, 348/384.1, 348/390.1, 348/425.1, 348/425.2, 348/420.1, 348/469, 348/384, 348/390
• US Class Current: 375/240.27
• CPC Class Codes: H04N 19/00 Methods or arrangements for coding, decoding, compressing or decompressing digital video signals
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/172 the region being a picture, frame or field
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/89 involving methods or arrangements for detection of transmission errors at the decoder

Abstract

A method of video encoding including: receiving a video signal to be coded; coding data representing a frame of said video signal; and repeating part, but not all, of the data. The repeated part including the picture header for the frame. A method of decoding an encoded video signal including receiving coded data representing frames of a video signal; examining the coded data to detect header data and picture data; when an error in the picture header is detected, storing the picture data in a temporary picture data store, detecting a repeat of the header data; and decoding the stored picture data using the repeated header data.

Claims

1. A method of decoding a compression encoded video signal, the method comprising:

receiving compression encoded data representative of a first frame of a video signal; and

examining said compression encoded data representative of the first frame to detect picture header data and picture data; and

wherein

when an error in the picture header data of the first frame is detected, storing the picture data of the first frame in a temporary picture data store, receiving compression encoded data subsequent to the first frame, detecting a repeat of the picture header data of the first frame from within the compression encoded data subsequent to the first frame, and decoding the stored picture data using the repeated picture header data.

2. A method of decoding according to claim 1 wherein the step of detecting a repeat of picture header data comprises:

ascertaining whether the compression encoded data subsequent to the first frame relates to an entire frame of the video signal or to an incomplete part of a frame and detecting a repeat of picture header data of the first frame when the compression encoded data subsequent to the first frame relates to an incomplete part of a frame.

3. A method of decoding according to claim 1 wherein the step of detecting a repeat of picture header data comprises:

ascertaining whether the compression encoded data subsequent to the first frame includes picture header data and further data, which further data signifies that a frame of the video signal is unaltered with respect to a reference frame of the video signal and, if so, determining that a repeat of the picture header data of the first frame has been detected.

4. A method of decoding according to claim 1, wherein the step of detecting a repeat of picture header data is carried out each time data is stored in the temporary picture data store.

5. A method of decoding according to claim 1, wherein the step of detecting the repeated picture header data comprises examining the picture header data of a subsequent frame to determine whether the picture header data of the subsequent frame includes data relating to the picture header data of the first frame and, if so, detecting a repeat of the picture header data of the first frame.

6. A method of decoding according to claim 5, wherein the step of detecting the repeated picture header data of the first frame comprises examining Supplemental Enhancement Information (SEI) of the header of the subsequent frame.

7. A method of decoding according to claim 5, wherein the step of detecting the repeated picture header data comprises examining Supplemental Enhancement Information (SEI) of the header of a subsequent frame for a repeat of the picture header data of the first frame excluding the picture start code for the first frame.

8. A method of video decoding according to claim 1, comprising detecting a repeat of the picture header data when certain fields of the picture header data of the first frame are present in the picture header data of the subsequent frame.

9. A method of video encoding comprising:

receiving an uncompressed video signal to be compression encoded;

encoding data representing a first frame of said uncompressed video signal to form compression encoded data; and

repeating part, but not all, of said data representing the first frame within compression encoded data subsequent to the first frame, said repeated part including picture header data for the first frame.

10. A method of encoding according to claim 9, wherein part of the data is repeated only for frames which are encoded in an INTRA-frame manner.

11. A method of encoding according to claim 9, wherein the repeated data comprises picture header data and a first segment of picture data of the first frame.

12. A method of encoding according to claim 9, wherein said repeated data consists of picture header data and an indicator that no picture data has altered since a previous frame.

13. A method of encoding according to claim 9, wherein the step of repeating picture header data comprises adding the repeated picture header data to the picture header data of a subsequent frame.

14. A method of encoding according to claim 13, wherein the repeated picture header data is included in the Supplemental Enhancement Information (SEI) of the subsequent frame.

15. A method of encoding according to claim 14, wherein the repeated picture header data included in the Supplemental Enhancement Information (SEI) of the subsequent frame excludes the picture start code for the first frame.

16. A method of encoding according to claim 9, wherein repeating said data includes repeating certain fields of the picture header data of the first frame in the picture header data of a subsequent frame.

17. A video encoder comprising:

an input for receiving an uncompressed video signal to be compression encoded;

means for compression encoding data representing a first frame of said uncompressed video signal to form compression encoded data; and

the means for compression encoding data being arranged to repeat part, but not all, of said data representing the first frame within compression encoded data subsequent to the first frame, said repeated part including picture header data for the first frame.

18. An encoder according to claim 17, wherein the repeated data comprises picture header data and a first segment of picture data of the first frame.

19. An encoder according to claim 17, wherein said repeated data consists of picture header data and an indicator that no picture data has altered since a previous frame.

20. An encoder according to claim 17, wherein the encoder is arranged to repeat picture header data by adding the repeated picture header data to the picture header data of a subsequent frame.

21. An encoder according to claim 20, wherein the encoder is arranged to include the repeated picture header data in Supplemental Enhancement Information (SEI) of the subsequent frame.

22. An encoder according to claim 21, wherein the repeated picture header data included in the Supplemental Enhancement Information (SEI) of the subsequent frame excludes the picture start code for the first frame.

23. An encoder according to claim 20, wherein the encoder is arranged to include the repeated picture header data in the Supplemental Enhancement Information (SEI) of the subsequent frame excluding the picture start code for the first frame.

24. A video encoder according to claim 17, wherein the means for compression encoding data is arranged to repeat certain fields of the picture header data of the first frame in the picture header data of a subsequent frame.

26. A wireless communications device incorporating an encoder according to claim 17.

25. A video decoder for decoding a compression encoded video signal, the decoder comprising:

an input for receiving compression encoded data representative of a first frames of a video signal and compression encoded data subsequent to the first frame; and

decoding means for examining said compression encoded data representative of the first frame to detect picture header data and picture data;

said decoder being arranged to store the picture data of the first frame in a temporary picture data store when an error in the picture header data of the first frame is detected, to detect a repeat of the picture header data of the first frame from within the compression encoded data subsequent to the first frame, and to decode the stored picture data using the repeated picture header data.

27. A wireless communications device incorporating a decoder according to claim 25.

28. A decoder according to claim 25, wherein the decoder is arranged to ascertain whether the compression encoded data subsequent to the frame relates to an entire frame of the video signal or to an incomplete part of a frame, and to detect a repeat of picture header data of the first frame when the compression encoded data subsequent to the first frame relates to an incomplete part of a frame.

29. A decoder according to claim 25, wherein the decoder is arranged to ascertain whether the compression encoded data subsequent to the first frame includes picture header data and further data, which further data signifies that a frame of the video signal is unaltered with respect to a reference frame of the video signal and, if so, to determine that a repeat of the picture header data of the first frame has been detected.

30. A decoder according to claim 25, wherein the decoder is arranged to examine the picture header data of a subsequent frame to determine whether the picture header data of the subsequent frame includes data relating to the picture header data of the first frame and, if so, to detect a repeat of the picture header data of the first frame.

31. A decoder according to claim 30, arranged to detect repeated picture header data of a previous frame by examining Supplemental Enhancement Information (SEI) of the picture header of a subsequent frame.

32. A decoder according to claim 30, wherein the decoder is arranged to detect the repeated picture header data by examining Supplemental Enhancement Information (SEI) of the header of a subsequent frame for a repeat of the picture header data of the first frame excluding the picture start code for the first frame.

33. A video decoder according to claim 30, arranged to detect a repeat of the picture header data when certain fields of the picture header data of the first frame are present in the picture header data of the subsequent frame.

35. A decoder according to claim 30, wherein the decoder is arranged to detect the repeated picture header data of the first frame by examining the Supplemental Enhancement Information (SEI) of the header of the subsequent frame for a repeat of the picture header data of the first frame excluding the picture start code for the first frame.

34. A decoder according to clam 30, wherein the decoder is arranged to detect the repeated picture header data of the first frame by examining the Supplemental Enhancement Information (SEI) of the header of the subsequent frame.

36. A video codec comprising an encoder and decoder, the encoder comprising:

an input for receiving an uncompressed video signal to be compression encoded; and

means for compression encoding data representing a first frame of said uncompressed video signal to form compression encoded data;

the means for compression encoding data being arranged to repeat part, but not all, of said data representing the first frame within compression encoded data subsequent to the first frame, said repeated part including picture header data for the first frame;

the decoder comprising an input for receiving compression encoded data representative of a first frame of a video signal and compression encoded data subsequent to the first frame; and

decoding means for examining said compression encoded data representative of the first frame to detect picture header data and picture data;

said decoder being arranged to store the picture data of the first frame in a temporary picture data store when an error in the picture header data of the first frame is detected, to detect a repeat of the picture header data from within the compression encoded data subsequent to the first frame, and to decode the stored picture data using the repeated picture header data.