Grouping of image frames in video coding

• US 8,204,134 B2
• Filed: 01/25/2006
• Issued: 06/19/2012
• Est. Priority Date: 01/23/2002
• Status: Active Grant

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Hannuksela, Miska
• Primary Examiner(s): LEE, SIU M
• Application Number:
  US11/338,996
• Publication Number:
  US 20060120464A1
• Time in Patent Office: 2,337 Days
• Field of Search: 375/240.27, 375/240.25
• US Class Current: 375/240.27
• CPC Class Codes: H04N 19/105 Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction
• CPC Class Codes: H04N 19/114 Adapting the group of pictures [GOP] structure, e.g. number of B-frames between two anchor frames H04N19/107 takes precedence
• CPC Class Codes: H04N 19/132 Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking
• CPC Class Codes: H04N 19/142 Detection of scene cut or scene change
• CPC Class Codes: H04N 19/152 by measuring the fullness of the transmission buffer
• CPC Class Codes: H04N 19/17 the unit being an image region, e.g. an object
• CPC Class Codes: H04N 19/172 the region being a picture, frame or field
• CPC Class Codes: H04N 19/31 in the temporal domain
• 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 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/577 Motion compensation with bidirectional frame interpolation, i.e. using B-pictures
• CPC Class Codes: H04N 19/587 involving temporal sub-sampling or interpolation, e.g. decimation or subsequent interpolation of pictures in a video sequence
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/65 using error resilience
• CPC Class Codes: H04N 19/70 characterised by syntax aspects related to video coding, e.g. related to compression standards
• CPC Class Codes: H04N 19/895 in combination with error concealment

Abstract

A method of decoding a compressed video sequence, wherein image frames are entered into a buffer memory in connection with the decoding. The video sequence includes an indication relating to at least one discontinuity in the numbering of the image frames, which indication is decoded from the video sequence. Then, in response to the indication, the buffer memory is configured to provide a number of image frames corresponding to a discontinuity in the numbering of the image frames, and the image frames provided by the buffer memory are used in the decoding process. Preferably, said indication informs that at least one discontinuity in the numbering of the image frames in the video sequence are intentional, and the number of image frames provided by the buffer memory are used in place of image frames that do not exist at a decoder.

Claims

1. A method for decoding a compressed video sequence, wherein image frames are entered into a buffer memory in connection with the decoding, the method comprising:

decoding from the compressed video sequence an indication informing an intentional discontinuity of numbering of the image frames;

configuring, in response to the indication, the buffer memory to provide a number of image frames corresponding to at least one discontinuity in the numbering of the image frames; and

using the image frames in the buffer memory in the decoding process.

2. A method according to claim 1, further comprising

using the number of image frames in the buffer memory in place of image frames that do not exist at a decoder due to the at least one discontinuity in the numbering of the image frames.

3. A method according to claim 1, wherein the number of image frames in the buffer memory are used in sliding window buffering of image frames.

4. A method according to claim 1, further comprising

continuing the entering of the image frames comprised by the compressed video sequence into the buffer memory from a correct image frame number after the buffer memory has been configured to provide the number of image frames corresponding to the at least one discontinuity in the numbering of the image frames.

5. A method according to claim 1, further comprising

entering into the buffer memory a number of filler frames corresponding to the at least one discontinuity in the numbering of the image frames.

6. A method according to claim 5, wherein

said filler frames are designated by an identifier indicating that the filler frames do not belong to the compressed video sequence.

7. A method according to claim 1, wherein

configuring the buffer memory to provide a number of image frames corresponding to the at least one discontinuity in the numbering of the image frames is carried out by memory indications, whereby no data is entered into the buffer memory.

8. A method according to claim 2, further comprising

detecting an error in the compressed video sequence on a basis of a reference in the decoding process to an image frame corresponding to the at least one discontinuity in the numbering of image frames.

9. A video decoder for decoding a compressed video sequence, the video decoder being connected to a buffer memory wherein image frames are entered in connection with the decoding, the video decoder being configured to

decode from the compressed video sequence an indication informing an intentional discontinuity of numbering of the image frames;

configure, in response to the indication, the buffer memory to provide a number of image frames corresponding to at least one discontinuity in the numbering of the image frames; and

use the image frames in the buffer memory in the decoding process.

10. A video decoder according to claim 9, wherein the video decoder is further configured to

use the number of image frames in the buffer memory in place of image frames that do not exist at a decoder due to the at least one discontinuity in the numbering of the image frames.

11. A video decoder according to claim 9, wherein

the number of image frames in the buffer memory are used in sliding window buffering of image frames.

12. A video decoder according to claim 9, wherein the video decoder is further configured to

continue the entering of the image frames comprised by the compressed video sequence into the buffer memory from a correct image frame number after the buffer memory has been configured to provide the number of image frames corresponding to the at least one discontinuity in the numbering of the image frames.

13. A video decoder according to claim 9, wherein the video decoder is further configured to

enter into the buffer memory a number of filler frames corresponding to the at least one discontinuity in the numbering of the image frames.

14. A video decoder according to claim 13, wherein

said filler frames are designated by an identifier indicating that the filler frames do not belong to the compressed video sequence.

15. A video decoder according to claim 9, wherein the video decoder is further configured to

configure the buffer memory to provide a number of image frames corresponding to the at least one discontinuity in the numbering of the image frames by memory indications, whereby no data is entered into the buffer memory.

16. A computer program product, stored on a non-transitory computer readable medium and executable in a data processing device, for decoding a compressed video sequence, image frames of said video sequence being entered into a buffer memory in connection with the decoding, the computer program product comprising:

a computer program code for decoding from the compressed video sequence an indication informing an intentional discontinuity of numbering of the image frames;

a computer program code for configuring, in response to the indication, the buffer memory to provide a number of image frames corresponding to at least one discontinuity in the numbering of the image frames; and

a computer program code for including the image frames in the buffer memory in the decoding process.

17. A computer program product according to claim 16, the computer program product further comprising:

a computer program code for including the number of image frames in the buffer memory in place of image frames that do not exist at a decoder due to the at least one discontinuity in the numbering of the image frames.

18. A computer program product according to claim 16, the computer program product further comprising

a computer program code for using the number of image frames in the buffer memory in sliding window buffering of image frames.

19. A computer program product according to claim 16, the computer program product further comprising

a computer program code for continuing the entering of the image frames comprised by the compressed video sequence into the buffer memory from a correct image frame number after the buffer memory has been configured to provide the number of image frames corresponding to the at least one discontinuity in the numbering of the image frames.

20. A computer program product according to claim 16, the computer program product further comprising:

a computer program code for entering into the buffer memory a number of filler frames corresponding to the at least one discontinuity in the numbering of the image frames.

21. A computer program product according to claim 20, the computer program product further comprising:

a computer program code for designating said filler frames by an identifier indicating that the filler frames do not belong to the compressed video sequence.

22. A computer program product according to claim 16, the computer program product further comprising:

a computer program code for configuring the buffer memory to provide a number of image frames corresponding to the at least one discontinuity in the numbering of the image frames by memory indications, whereby no data is entered into the buffer memory.