Method and apparatus for intra mode derivation and coding in scalable video coding

Patent metadata

Field	Value
Publication number	US-10091515-B2
Application number	US-201314378949-A
Country	US
Kind code	B2
Filing date	Mar 11, 2013
Priority date	Mar 21, 2012
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A method and apparatus of Intra mode coding for a scalable video coding system are disclosed. For a current Intra-coded block in the enhancement layer (EL), predictive coding is applied to the current Intra mode based on the base layer (BL) coding mode associated with the co-located block in the BL and neighboring coding modes associated with neighboring blocks of the current block in the EL. The neighboring blocks of the current block in the EL comprise a left block adjacent to a left side of the current block and a top block adjacent to a top side of the current block. One or more most probable modes (MPMs) can be derived from the neighboring coding modes and the BL coding mode, and the MPMs is then used for predictive coding of the current Intra mode.

First claim

The invention claimed is:

1. A method of Intra mode coding for a scalable video coding system, wherein video data is configured into a Base Layer (BL) and an Enhancement Layer (EL), wherein the EL has higher spatial resolution or better video quality than the BL, a co-located block in the BL corresponding to a current block in the EL is coded before the current block, and the current block is Intra coded, the method comprising:
receiving information associated with a current Intra mode of the current block in the EL from a media or a processor;
determining a BL coding mode associated with the co-located block in the BL;
determining one or more neighboring coding modes associated with one or more neighboring blocks of the current block in the EL; and
applying predictive coding to the current Intra mode based on the BL coding mode associated with the co-located block in the BL and said one or more neighboring coding modes associated with one or more neighboring blocks of the current block in the EL,
wherein if one neighboring block of the current block in the EL is not available or is not Intra coded, a neighboring coding mode associated with said one neighboring block is replaced by a reference BL coding mode during said predictive coding of the current Intra mode, wherein the reference BL coding mode is associated with a reference block in the BL, and wherein the reference block is a neighbor co-located block in the BL corresponding to said one neighboring block of the current block in the EL.

2. The method of claim 1 , wherein said one or more neighboring blocks of the current block in the EL comprise a left block adjacent to a left side of the current block and a top block adjacent to a top side of the current block, the left block is associated with a left-block coding mode, and the top block is associated with a top-block coding mode.

3. The method of claim 2 , wherein two or more most probable modes are derived from the BL coding mode, the left-block coding mode and the top-block coding mode.

4. The method of claim 2 , wherein three most probable modes are derived from the BL coding mode, the left-block coding mode and the top-block coding mode.

5. The method of claim 4 , wherein the three most probable modes correspond to {Planar mode, DC mode, Vertical mode} if none of the BL coding mode, the left-block coding mode and the top-block coding mode is an Intra mode.

6. The method of claim 4 , wherein the three most probable modes correspond to {Planar mode, DC mode, Vertical mode} if the BL coding mode, the left-block coding mode and the top-block coding mode correspond to a same Intra mode and said same Intra mode is the Planar mode or the DC mode.

7. The method of claim 4 , wherein, if one or more than one member of the BL coding mode, the left-block coding mode and the top-block coding mode are an Intra mode corresponding to a same Intra mode and said same Intra mode is neither Planar mode nor DC mode, the three most probable modes correspond to {said same Intra mode, (said same Intra mode−1), (said same Intra mode+1)}.

8. The method of claim 4 , wherein, if two or more than two members of the BL coding mode, the left-block coding mode and the top-block coding mode are Intra modes corresponding to a first Intra mode and a second Intra mode, and the first Intra mode is different from the second Intra mode, the three most probable modes correspond to {the first Intra mode, the second Intra mode, Planar mode} if neither the first Intra mode nor the second Intra mode equals to the Planar mode; the three most probable modes correspond to {the first Intra mode, the second Intra mode, DC mode} if neither the first Intra mode nor the second Intra mode equals to the DC mode, and one of the first Intra mode and the second intra mode equals to the Planar mode; and the three most probable modes correspond to {the first Intra mode, the second Intra mode, Vertical mode} if the first Intra mode or the second Intra mode equals to the Planar mode or the DC mode.

9. The method of claim 4 , wherein, if the BL coding mode, the left-block coding mode and the top-block coding mode correspond to three different Intra modes, the three most probable modes correspond to {the BL coding mode, the left-block coding mode, the top-block coding mode}.

10. The method of claim 4 , wherein if the BL coding mode, the left-block coding mode or the top-block coding mode is Planar mode, the Planar mode is excluded from the three most probable modes; and if the BL coding mode, the left-block coding mode or the top-block coding mode is DC mode, the DC mode is excluded from initial assignment of the three most probable modes.

11. The method of claim 10 , wherein, if none of the BL coding mode, the left-block coding mode and the top-block coding mode is an Intra mode not equal to Planar or DC, the three most probable modes correspond to {the DC mode, Vertical mode, Horizontal mode}.

12. The method of claim 10 , wherein, if the BL coding mode, the left-block coding mode and the top-block coding mode correspond to a same angular Intra mode, the three most probable modes correspond to {the same angular Intra mode, (the same angular Intra mode−1), (the same angular Intra mode+1)}.

13. The method of claim 10 , wherein, if the BL coding mode, the left-block coding mode and the top-block coding mode correspond to a first angular Intra mode and a second angular Intra mode, and the first Intra angular mode is different from the second Intra angular mode, the three most probable modes correspond to {the first Intra angular mode, the second Intra angular mode, the DC mode}.

14. The method of claim 10 , wherein, if the BL coding mode, the left-block coding mode and the top-block coding mode correspond to three different angular Intra modes, the three most probable modes correspond to {the BL coding mode, the left-block coding mode, the top-block coding mode}.

15. The method of claim 2 , wherein one most probable mode is derived from the BL coding mode, the left-block coding mode and the top-block coding mode.

16. The method of claim 15 , wherein said one most probable mode corresponds to the BL coding mode if the BL coding mode corresponds to a first Intra mode not equal to Planar mode or DC mode; said one most probable mode corresponds to the left-block coding mode if the BL coding mode is not any Intra mode and the left-block coding mode corresponds to a second Intra mode not equal to the Planar mode or the DC mode; and said one most probable mode corresponds to the top-block coding mode if the BL coding mode and the left-block coding mode are not any Intra mode and the top-block coding mode corresponds to a third Intra mode not equal to the Planar mode or the DC mode.

17. The method of claim 15 , wherein 33 angular Intra prediction modes are used for the EL and 32 remaining modes are represented by 5 bin fixed length coding.

18. The method of claim 1 , wherein one or more most probable modes are derived from said one or more neighboring coding modes associated with one or more neighboring blocks of the current block in the EL and the BL coding mode associated with the co-located block in the BL, and said one or more most probable modes are used for said predictive coding of the current Intra mode.

19. The method of claim 1 , wherein a most probable mode set is determined for coding to the current Intra mode based, and the most probable mode set comprises at least one most probable mode.

20. An apparatus of Intra mode coding for a scalable video coding system, wherein video data

Assignees

• Liu Shan
• Guo Mei
• Chuang Tzu Der
• Lei Shaw Min
• Mediatek Singapore Pte Ltd

Inventors

• Liu Shan
• Guo Mei
• Chuang Tzu-Der
• Lei Shaw-Min

Classifications

• H04N19/176

  the region being a block, e.g. a macroblock · CPC title

• H04N19/157

  Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter · CPC title

• H04N19/96 Primary

  Tree coding, e.g. quad-tree coding · CPC title

• H04N19/11

  among a plurality of spatial predictive coding modes · CPC title

• H04N19/463

  by compressing encoding parameters before transmission · CPC title