Method and apparatus for encoding/decoding image
The objective of the present invention is to provide a method and an apparatus for intra-prediction. In addition, the objective of the present invention is to provide a method and an apparatus for intra-prediction on a subblock unit basis. Furthermore, the objective of the present invention is to provide a method and an apparatus for determining a division and an encoding order of subblock units.
1. An image decoding method performed by an image decoding apparatus, the method comprising:
generating a coding block using tree-based partitioning, the tree-based partitioning comprising splitting a square block into four square blocks having a same size with each other;
generating a plurality of sub-blocks by performing index-based partitioning for the coding block, the index-based partitioning comprising a first partitioning and a second partitioning, the first partitioning splits a 4N×4M coding block into four identical 4N×N sub-blocks or four identical N×4M sub-blocks, N being equal to or different from M, and the second partitioning splits a coding block into two equal parts horizontally or vertically; and
generating a prediction block of the coding block by performing intra prediction for each of the plurality of the sub-blocks,
wherein the intra prediction for the each of the plurality of the sub-blocks is performed based on a same intra prediction mode, and
wherein whether to perform the first partitioning or the second partitioning is determined based on a size of the coding block.
2. The image decoding method of claim 1 , further comprising:
determining whether to perform the index-based partitioning for the coding block further based on a property of the coding block.
3. The image decoding method of claim 2 ,
wherein the property of the coding block comprises at least one of an area, width or height of the coding block.
4. The image decoding method of claim 1 ,
wherein a partitioning type of the index-based partitioning is determined further based on an index signaled for the coding block or a property of the coding block.
5. An image encoding method performed by an image encoding apparatus, the method comprising:
generating a coding block using tree-based partitioning, the tree-based partitioning comprising splitting a square block into four square blocks having a same size with each other;
generating a plurality of sub-blocks by performing index-based partitioning for the coding block, the index-based partitioning comprising a first partitioning and a second partitioning, the first partitioning splits a 4N×4M coding block into four identical 4N×M sub-blocks or four identical N×4M sub-blocks, N being equal to or different from M, and the second partitioning splits a coding block into two equal parts horizontally or vertically; and
generating a prediction block of the coding block by performing intra prediction for each of the plurality of the sub-blocks,
wherein the intra prediction for the each of the plurality of the sub-blocks is performed based on a same intra prediction mode, and
wherein whether to perform the first partitioning or the second partitioning is determined based on a size of the coding block.
6. A non-transitory computer-readable recording medium storing a bitstream which is generated by an image encoding method, the method comprising:
generating a coding block using tree-based partitioning, the tree-based partitioning comprising splitting a square block into four square blocks having a same size with each other;
generating a plurality of sub-blocks by performing index-based partitioning for the coding block, the index-based partitioning comprising a first partitioning and a second partitioning, the first partitioning, splits a 4N×4M coding block into four identical 4N×M sub-blocks or four identical N×4M sub-blocks, N being equal to or different from M, and the second partitioning splits a coding block into two equal parts horizontally or vertically; and
generating a prediction block of the coding block by performing intra prediction for each of the plurality of the sub-blocks,
wherein the intra prediction for the each of the plurality of the sub-blocks is performed based on a same intra prediction mode, and
wherein whether to perform the first partitioning or the second partitioning is determined based on a size of the coding block.
7. A non-transitory computer-readable recording medium having stored thereon instructions that when executed by a processor perform an image decoding method, the method comprising:
generating a coding block using tree-based partitioning, the tree-based partitioning comprising splitting a square block into four square blocks having a same size with each other;
generating a plurality of sub-blocks by performing index-based partitioning for the coding block, the index-based partitioning comprising a first partitioning and a second partitioning, the first partitioning splits a 4N×4M coding block into four identical 4N×M sub-blocks or four identical N×4M sub-blocks, N being equal to or different from M, and the second partitioning splits a coding block into two equal parts horizontally or vertically; and
generating a prediction block of the coding block by performing intra prediction for each of the plurality of the sub-blocks,
wherein the intra prediction for the each of the plurality of the sub-blocks is performed based on a same intra prediction mode, and
wherein whether to perform the first partitioning or the second partitioning is determined based on a size of the coding block.