System and method for transcoding between scalable and non-scalable video codecs

• US 8,320,450 B2
• Filed: 03/29/2007
• Issued: 11/27/2012
• Est. Priority Date: 03/29/2006
• Status: Active Grant

• Current Assignee: Vidyo Incorporated (Enghouse Systems Limited)
• Original Assignee: Vidyo Incorporated (Enghouse Systems Limited)
• Inventors: Eleftheriadis, Alexandros, Hong, Danny, Shapiro, Ofer, Wiegand, Thomas
• Primary Examiner(s): PEARSON, DAVID J
• Application Number:
  US11/693,694
• Publication Number:
  US 20070230568A1
• Time in Patent Office: 2,070 Days
• Field of Search: None
• US Class Current: 375/240.12
• CPC Class Codes: H04N 19/31 in the temporal domain
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• 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 19/48 using compressed domain processing techniques other than decoding, e.g. modification of transform coefficients, variable length coding [VLC] data or run-length data motion estimation in a transform domain H04N19/547; processing of decoded motion vectors H04N19/513
• CPC Class Codes: H04N 19/51 Motion estimation or motion compensation
• CPC Class Codes: H04N 19/61 in combination with predictive coding

Abstract

Systems and methods are provided for performing transcoding in video communication system that use scalable video coding. The systems and methods can be used to transcode or convert input signals having certain characteristics into desired output signals having different characteristics requirements. The systems and methods are based on compressed domain processing, partial decoding-reencoding, or full decoding-reencoding with side information, depending on the specific characteristics of the input and desired output signals.

Claims

1. A digital video signal processing system comprising:

a video processing unit (“

transcoder”

) with at least one digital video signal input and at least one digital video signal output,

wherein the input video coding format of the transcoder is SVC and the output video coding format of the transcoder is H.264,

and wherein the transcoder is configured to decode and combine individual layer coding parameters of the at least digital video signal input that is coded separately in different layers, and encode the combined parameters into single values at the at least one output video signal, so that the at least one digital video signal output has a desired quality resolution that is less than or equal to the input quality resolution.

2. The system of claim 1, wherein the individual coding parameters include transform coefficient data.

3. The system of claim 1, wherein the individual coding parameters include motion vector data.

4. The system of claim 1 wherein to minimize transcoding drift at least one of periodic intra macroblocks and a threaded temporal prediction structure is used in encoding of the input video signal.

5. A digital video signal processing system comprising:

a video processing unit (“

transcoder”

) with at least one digital video signal input and at least one digital video signal output;

at least one input video encoder; and

an electronic communication network that links the at least one input video encoder with the transcoder,

wherein the video coding format of the input video encoder is SVC, the input video coding format of the transcoder is SVC, and the output video coding format of the transcoder is H.264,

wherein the input video encoder is further configured so that SVC coded data can be represented exactly by H.264 for at least one picture contained in the SVC coded data,

and wherein the transcoder is further configured to decode and combine individual layer coding parameters of the at least one input signal that is coded separately in different layers, and encode the combined parameters into single values at the at least one output video signal so that the at least one output video signal has a desired quality resolution that is less than or equal to the input quality resolution.

6. The system of claim 5, wherein the individual coding parameters include transform coefficient data.

7. The system of claim 5, wherein the individual coding parameters include motion vector data.

8. The system of claim 5, wherein the input video encoder is further configured so that the QP difference in the transform coefficient data of a block in successive SVC layers is a multiple of 6.

9. The system of claim 5 wherein the input video encoder is further configured such that SVC coded data can be represented exactly by H.264 for a least the lowest temporal layer (LR) pictures.

10. A digital video signal processing system comprising:

a video processing unit (“

transcoder”

) with at least one digital video signal input and at least one digital video signal output;

wherein the input video coding format of the transcoder is H.264 and the output video coding format of the transcoder is SVC;

and wherein the transcoder is configured to partition individual layer coding parameters of the at least one input signal into a number of component(s), and separately code all or only a fraction of the number of components across the different layers of the at least one output video signal so that the at least one output video signal has at least a desired quality resolution that is less than the input quality resolution.

11. The system of claim 10, wherein the individual coding parameters include transform coefficient data.

12. The system of claim 11, wherein the partitioned components of the transform coefficient data include at least one of:

coefficient data corresponding to different frequencies;

sets of values that when added together result in the original coefficient data value; and

a combination thereof.

13. The system of claim 11, wherein the encoding of the transform coefficient data within the layers of the at least one output video signal is such that the QP difference in a block in successive layers is a multiple of 6.

14. The system of claim 10, wherein the individual coding parameters include motion vector data.

15. The system of claim 14, wherein the partitioned components of the motion vector data include at least one of:

motion vector data corresponding to different spatial locations;

sets of values that when added together result in the original motion vector data; and

any combination thereof.

16. The system of claim 10, wherein the transcoder is further configured to partition individual layer coding parameters of the at least one input signal using rate-distortion optimization within each layer with the distortion corresponding to the drift within the each layer.

17. The system of claim 10, wherein to eliminate transcoding drift the encoding format of the input video signal is further configured to perform intra prediction using reference samples in enhancement layers.

18. A digital video signal processing system comprising:

a video processing unit (“

transcoder”

) with at least one digital video signal input and at least one digital video signal output,

wherein the input video coding format of the transcoder is SVC, wherein the output video coding format of the transcoder is SVC and contains the same spatial, temporal, and quality resolutions of the input video coding format except for the highest layer of the input video coding format, and

wherein the transcoder is configured to partition individual coding parameters of the highest layer of the at least one input signal into a number of component(s), and separately code all or only a fraction of the number of components across the different layers of the at least one output video signal so that the at least one output video signal has at least a desired quality resolution that is less than the quality resolution of the highest layer of the at least one input video signal.

19. The system of claim 18, wherein the individual coding parameters include at least one of transform coefficient data and refinements thereof.

20. The system of claim 19, where the partitioned transform coefficient data include at least one of:

transform coefficients or refinements thereof corresponding to different frequencies;

sets of values that when added together result in an original coefficient or refinement value; and

any combination thereof.

21. The system of claim 19, wherein the encoding of the transform coefficients or refinements thereof within the layers of the at least one output video signal is such that the QP difference in a block in successive layers is a multiple of 6.

22. The system of claim 18, wherein the individual coding parameters include motion vector data or refinements thereof.

23. The system of claim 22, where the partitioned motion vector components include at least one of:

motion vectors or refinements thereof corresponding to different spatial locations;

sets of values that when added together result in the original motion vector or motion vector refinement; and

a combination thereof.

24. The system of claim 18, wherein the transcoder further configured to partition individual layer coding parameters of the at least one input signal using rate-distortion optimization within each layer with the distortion corresponding to the drift within the each layer.

25. The system of claim 18, wherein to eliminate transcoding drift the encoding format of the input video signal is further configured to perform intra prediction using reference samples in enhancement layers.

26. A digital video signal processing system comprising:

a video processing unit (“

transcoder”

) with at least one digital video signal input and at least one digital video signal output,

wherein the input video coding fauna of the transcoder is SVC, wherein the output video coding format of the transcoder is H.264 with a spatial resolution that is among the spatial resolutions provided by the input video coding format,

and wherein the transcoder is configured to;

decode and combine individual layer coding parameters of the at least one input signal that is coded separately in different layers, and encode the combined parameters into single values at the at least one output video signal when the equivalent syntax is available in the output video coding format, and encode an approximation to the combined parameters into the at least one output video signal when an exact encoding is not available in the output video coding format.

27. The system of claim 26, wherein the individual coding parameters include transform coefficient data.

28. The system of claim 26, wherein the individual coding parameters include motion vector data.

29. The system of claim 26, wherein the transcoder if further configured encode an approximation to the combined parameters of the at least one input video signal using rate-distortion optimization, wherein the distortion corresponds to the drift.

30. The system of claim 26 wherein to minimize transcoding drift one of periodic intra macroblocks and a threaded temporal prediction structure is used in encoding of the input video signal.

31. A method for transcoding at least one digital video signal input and at least one digital video signal output, wherein the input video coding format is SVC and the output video coding format is H.264, the method comprising:

decoding and combining individual layer coding parameters of the at least digital video signal input that is coded separately in different layers; and

encoding the combined parameters into single values in the at least one output video signal so that the at least one digital video signal output has a desired quality resolution that is less than or equal to the input quality resolution.

32. The method of claim 31, wherein the individual coding parameters include transform coefficient data.

33. The method of claim 31, wherein the individual coding parameters include motion vector data.

34. The method of claim 31 further comprising:

using at least one of periodic intra macroblocks and a threaded temporal prediction structure in encoding of the input video signal to minimize transcoding drift.

61. A non-transitory computer readable medium comprising a set of executable instructions for performing the methods of one of claims 31-60.

35. A method for encoding at least one digital video signal input over an electronic communication network to a transcoder for transcoding to at least one digital video signal output at the transcoder, wherein the input video coding format is SVC and the output video coding format is H.264, the method comprising:

encoding the at least one digital video signal input as SVC coded data that can be represented exactly by H.264 for at least one picture contained in the SVC coded data; and

at the transcoder decoding and combining individual layer coding parameters of the at least one input signal that is coded separately in different layers, and encoding the combined parameters into single values in the at least one output video signal so that the at least one output video signal has a desired quality resolution that is less than or equal to the input quality resolution.

36. The method of claim 35, wherein the individual coding parameters include transform coefficient data.

37. The method of claim 35, wherein the individual coding parameters include motion vector data.

38. The method of claim 35, further comprising encoding so that the QP difference in the transform coefficient data of a block in successive SVC layers is a multiple of 6.

39. The method of claim 35, further comprising encoding so that SVC coded data can be represented exactly by H.264 for at least the lowest temporal layer (LR) pictures.

40. A method for transcoding at least one digital video signal input and at least one digital video signal output, wherein the input video coding format is SVC and the output video coding format is H.264, the method comprising:

partitioning individual layer coding parameters of the at least one input signal into a number of component(s); and

separately coding all or only a fraction of the number of components across the different layers of the at least one output video signal so that the at least one output video signal has at least a desired quality resolution that is less than the input quality resolution.

41. The method of claim 40, wherein the individual coding parameters include transform coefficient data.

42. The method of claim 41, wherein the partitioned components of the transform coefficient data include at least one of:

coefficient data corresponding to different frequencies;

sets of values that when added together result in the original coefficient data value; and

a combination thereof.

43. The method of claim 41, wherein the encoding of the transform coefficient data within the layers of the at least one output video signal is such that the QP difference in a block in successive layers is a multiple of 6.

44. The method of claim 40, wherein the individual coding parameters include motion vector data.

45. The method of claim 44, wherein the partitioned components of the motion vector data include at least one of:

motion vector data corresponding to different spatial locations;

sets of values that when added together result in the original motion vector data; and

a combination thereof.

46. The method of claim 40, wherein partitioning individual layer coding parameters of the at least one input signal comprises using rate-distortion optimization within each layer with the distortion corresponding to the drift within the each layer.

47. The method of claim 40, wherein to eliminate transcoding drift the encoding format of the input video signal is further configured to perform intra prediction using reference samples in enhancement layers.

48. A method for transcoding at least one digital video signal input and at least one digital video signal output, wherein the input video coding format is SVC, wherein the output video coding format is SVC and contains the same spatial, temporal, and quality resolutions of the input video coding format except for the highest layer of the input video coding format, the method comprising:

partitioning individual layer coding parameters of the highest layer of the at least one input signal into a number of component(s); and

separately coding all or only a fraction of the number of the components across the different layers of the at least one output video signal so that the at least one output video signal has at least a desired quality resolution that is less than the quality resolution of the highest layer of the at least one input video signal.

49. The method of claim 48, wherein the individual coding parameters include at least one of transform coefficient data and refinements thereof.

50. The method of claim 49, where the partitioned transform coefficient data include at least one of:

transform coefficients or refinements thereof corresponding to different frequencies;

sets of values that when added together result in an original coefficient or refinement value; and

a combination thereof.

51. The method of claim 49, wherein the encoding of the transform coefficients or refinements thereof within the layers of the at least one output video signal is such that the QP difference in a block in successive layers is a multiple of 6.

52. The method of claim 48, wherein the individual coding parameters include motion vector data or refinements thereof.

53. The method of claim 52, where the partitioned motion vector components include at least one of:

motion vectors or refinements thereof corresponding to different spatial locations;

sets of values that when added together result in the original motion vector or motion vector refinement; and

a combination thereof.

54. The method of claim 48, wherein partitioning individual layer coding parameters of the at least one input signal comprises using rate-distortion optimization within each layer with the distortion corresponding to the drift within the each layer.

55. The method of claim 48, wherein to eliminate transcoding drift the encoding format of the input video signal is configured to perform intra prediction using reference samples in enhancement layers.

56. A method for transcoding at least one digital video signal input and at least one digital video signal output, wherein the input video coding format is SVC, wherein the output video coding format is H.264 with a spatial resolution that is among the spatial resolutions provided by the input video coding format, the method comprising:

decoding and combining individual layer coding parameters of the at least one input signal that is coded separately in different layers; and

encoding the combined parameters into single values at the at least one output video signal when the equivalent syntax is available in the output video coding format, and encoding an approximation to the combined parameters into the at least one output video signal when an exact encoding is not available in the output video coding format.

57. The method of claim 56, wherein the individual coding parameters include transform coefficient data.

58. The method of claim 56, wherein the individual coding parameters include motion vector data.

59. The method of claim 56, wherein encoding an approximation to the combined parameters of the at least one input video signal comprises using rate- distortion optimization, wherein the distortion corresponds to the drift.

60. The method of claim 56, further comprising to minimize transcoding drift using one of periodic intra macroblocks and a threaded temporal prediction structure in encoding of the input video signal.