Method and system for inter-layer prediction mode coding in scalable video coding

• US 20060153295A1
• Filed: 01/11/2006
• Published: 07/13/2006
• Est. Priority Date: 01/12/2005
• Status: Abandoned Application

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Karczewicz, Marta, Wang, Xianglin, Bao, Yiliang, Ridge, Justin
• Application Number:
  US11/331,433
• Publication Number:
  US 20060153295A1
• Time in Patent Office: Days
• US Class Current: 375/240.80
• CPC Class Codes: H04N 19/107 between spatial and temporal predictive coding, e.g. picture refresh
• CPC Class Codes: H04N 19/13 Adaptive entropy coding, e.g. adaptive variable length coding [AVLC] or context adaptive binary arithmetic coding [CABAC]
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/187 the unit being a scalable video layer
• CPC Class Codes: H04N 19/33 in the spatial 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 19/48 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 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/615 using motion compensated temporal filtering [MCTF]
• CPC Class Codes: H04N 19/63 using sub-band based transform, e.g. wavelets

Abstract

The present invention improves residue prediction by using MI even when the base layer MB is encoded in intra mode such as copying intra 4×4 mode of one 4×4 block in the base layer to multiple neighboring 4×4 blocks in the enhancement layer if the base layer resolution is lower than the enhancement layer resolution, using the intra 4×4 mode as intra 8×8 mode if the base layer resolution is lower than the enhancement layer resolution and the base layer resolution is half of the enhancement layer resolution in both dimensions, carrying out direct calculation of the base layer prediction residue used in RP, clipping of prediction residue for reducing memory requirement and tunneling of prediction residue in BLTP mode; and conditional coding of RP flag to save flag bits and reduce implementation complexity

Claims

1. A method for use in scalable video coding for reducing redundancy existing in scalable video layers, the layers comprising a base layer and at least one enhancement layer, each layer comprising at least one macroblock, said method comprising:

determining whether to use a residue prediction mode in coding a macroblock in the enhancement layer; and

if the residue prediction mode is used, coding a residual prediction flag into the enhancement layer bit stream, said flag indicating whether residual prediction is applied to the macroblock in the enhancement layer; and

if the residue prediction mode is not used, omitting the residual prediction flag from the enhancement layer bit stream for said macroblock.

2. The method of claim 1, wherein said determining is based on whether base layer residual is zero.

3. The method of claim 1, wherein said determining is based on a manner in which the macroblock in the base layer is coded.

4. The method of claim 1, wherein the determination is based on the type of collocated macroblocks in the base layer

5. The method of claim 3, wherein the residue prediction mode is not used if none of the collocated macroblocks in the base layer are inter-coded.

6. The method of claim 1, wherein the residue prediction mode is not used if a coded block pattern for the base layer macroblock is zero

7. The method of claim 6, wherein the base layer and at least one enhancement layer are of different spatial resolutions, and wherein the residue prediction mode is not used if a bit from the base layer coded block pattern is set to zero, said bit corresponding to a macroblock that would be collocated with the particular enhancement layer macroblock if upsampling of the base layer were to occur.

8. The method of claim 1, wherein the additional step of computing mode inheritance either precedes or follows said determination.

9. The method of claim 8, wherein the base layer and enhancement layer have equal spatial resolution, and wherein the mode of the particular macroblock in the enhancement layer is inherited from the collocated base layer macroblock, and the collocated base layer macroblock is an intra-macroblock.

10. The method of claim 8, wherein the enhancement layer has a larger spatial resolution than the base layer, and wherein the mode of an intra-macroblock in the base layer is inherited from a base layer macroblock which, if upsampled, would encompass the particular enhancement layer macroblock.

18. A software application product comprising a storage medium having a software application for use in scalable video coding for reducing redundancy existing in scalable video layers, the layers comprising a base layer and at least one enhancement layer, each layer comprising at least one macroblock, said software application comprising program codes for carrying out the method steps of claim 1.

11. A scalable video encoder for coding for reducing redundancy existing in scalable video layers, the layers comprising a base layer and at least one enhancement layer, each layer comprising at least one macroblock, said encoder comprising:

means for determining whether to use a residue prediction mode in coding a macroblock in the enhancement layer; and

means for coding a residual prediction flag into the enhancement layer bit stream if the residue prediction mode is used, said flag indicating whether residual prediction is applied to the macroblock in the enhancement layer; and

if the residue prediction mode is not used, omitting the residual prediction flag from the enhancement layer bit stream for said macroblock.

12. The encoder of claim 11, wherein said determining is based on whether base layer residual is zero.

13. The encoder of claim 11, wherein said determining is based on a manner in which the macroblock in the base layer is coded.

14. The encoder of claim 11, wherein the determination is based on the type of collocated macroblocks in the base layer

15. The encoder of claim 13, wherein the residue prediction mode is not used if none of the collocated macroblocks in the base layer are inter-coded.

16. The encoder of claim 11, wherein the residue prediction mode is not used if a coded block pattern for the base layer macroblock is zero

17. The encoder of claim 16, wherein the base layer and at least one enhancement layer are of different spatial resolutions, and wherein the residue prediction mode is not used if a bit from the base layer coded block pattern is set to zero, said bit corresponding to a macroblock that would be collocated with the particular enhancement layer macroblock if upsampling of the base layer were to occur.