Method and apparatus of syntax interleaving for separate coding tree in video coding
A methods and apparatus for block partition in video encoding and decoding are disclosed. According to one method, a current data unit is partitioned into initial blocks using inferred splitting without split-syntax signalling. The initial blocks comprises multiple initial luma blocks and multiple initial chroma blocks, and size of the initial luma block is M×N, M and N are positive integers and the current data unit is larger than M×N for the luma component. A partition structure is determined for partitioning each initial luma block and each initial chroma block into one or more luma CUs (coding units) and one or more chroma CUs respectively. The luma syntaxes and the chroma syntaxes associated with one initial block in the current data unit are signalled or parsed, and then the luma syntaxes and the chroma syntaxes associated with one next initial block in the current data unit are signalled or parsed.
1. A method of video coding used by a video coding system, the method comprising:
receiving input data associated with a current data unit in a current picture, wherein the input data associated with the current data unit comprise a luma component and a chroma component;
partitioning the current data unit into multiple initial blocks using inferred splitting without split-syntax signalling when the current data unit is larger than M×N for the luma component, wherein each of the multiple initial blocks comprises an initial luma block and an initial chroma block, and wherein M and N are positive integers;
determining a partition structure for partitioning the initial luma block and the initial chroma block of each initial block into one or more luma CUs (coding units) and one or more chroma CUs respectively; and
signalling or parsing one or more luma syntaxes and one or more chroma syntaxes associated with one initial block in the current data unit, and then signalling or parsing one or more luma syntaxes and one or more chroma syntaxes associated with one next initial block in the current data unit.
2. The method of claim 1 , wherein the current data unit corresponds to a CTU (coding tree unit).
3. The method of claim 1 , wherein the partition structure comprises separate coding trees for each initial block to partition the initial luma block and initial chroma block in each initial block.
4. The method of claim 1 , wherein said one or more luma syntaxes associated with said one initial block in the current data unit are signalled or parsed before said one or more chroma syntaxes associated with said one initial block in the current data unit.
5. The method of claim 1 , wherein the current data unit is partitioned using quadtree (QT) split into said multiple initial blocks having a block size equal to M×N for the luma component.
6. The method of claim 1 , wherein M×N corresponds to a predefined or derived block size, or maximum TU (transform unit) size, or a size related to the maximum TU size or minimum TU size.
7. The method of claim 1 , wherein information related to M and N is signalled at a sequence level, picture level, slice level, brick level, tile group level, or tile level.
8. The method of claim 7 , wherein the M and N equal to 64 for the luma component.
9. The method of claim 1 , wherein one or more shared-separate syntaxes are signalled or parsed for the current data unit to indicate whether the current data unit uses coding-tree-sharing or non-coding-tree-sharing.
10. The method of claim 9 , wherein if said one or more shared-separate syntaxes indicate that the current data unit uses coding-tree-sharing, all CUs (coding units) within the current data unit use the coding-tree-sharing.
11. The method of claim 9 , wherein if said one or more shared-separate syntaxes indicate that the current data unit uses non-coding-tree-sharing, all CUs (coding units) within the current data unit use the non-coding-tree-sharing.
12. The method of claim 9 , wherein the inferred splitting is applied when a current slice is I-slice or when the current slice is I-slice and the non-coding-tree-sharing is enabled.
13. An apparatus of video encoding and decoding used by a video encoding system and video decoding system respectively, the apparatus comprising one or more electronic circuits or processors arrange to:
receive input data associated with a current data unit in a current picture, wherein the input data associated with the current data unit comprise a luma component and a chroma component;
partition the current data unit into multiple initial blocks using inferred splitting without split-syntax signalling when the current data unit is larger than M×N for the luma component, wherein each of the multiple initial blocks comprises an initial luma block and an initial chroma block, and wherein M and N are positive integers;
determine a partition structure for partitioning the initial luma block and the initial chroma block of each initial block into one or more luma CUs (coding units) and one or more chroma CUs respectively; and
signal or parse one or more luma syntaxes and one or more chroma syntaxes associated with one initial block in the current data unit and then signal or parse one or more luma syntaxes and one or more chroma syntaxes associated with one next initial block in the current data unit.
14. The method of claim 9 , wherein if said one or more shared-separate syntaxes indicate that the current data unit uses non-coding-tree-sharing, partitioning the current data unit into multiple initial blocks using inferred splitting without split-syntax signalling when the current data unit is larger than M×N for the luma component; and determining a partition structure for partitioning the initial luma block and the initial chroma block of each initial block into one or more luma CUs and one or more chroma CUs respectively.