Methods and apparatus for signaling intra prediction for large blocks for video encoders and decoders

Patent metadata

Field	Value
Publication number	US-12120307-B2
Application number	US-202318227124-A
Country	US
Kind code	B2
Filing date	Jul 27, 2023
Priority date	Jul 1, 2009
Publication date	Oct 15, 2024
Grant date	Oct 15, 2024

Abstract

Methods and apparatus are provided for signaling intra prediction for large blocks for video encoders and decoders. An apparatus includes a video encoder for encoding picture data for at least one large block in a picture by signaling intra prediction for the at least one large block. The intra prediction is signaled by selecting a basic coding unit size and assigning a single spatial intra partition type for the basic coding unit size. The single spatial intra partition type is selectable from among a plurality of spatial intra partition types. The at least one large block has a large block size greater than a block size of the basic coding unit. The intra prediction is hierarchical layer intra prediction and is performed for the at least one large block by splitting from the large block size to the basic coding unit size.

First claim

The invention claimed is:

1. A video decoder, comprising at least a memory and one or more processors, wherein the one or more processors are configured to:
decode picture data for at least a large block in a picture by determining that intra prediction is to be performed for the at least a large block, wherein the at least a large block has a large block size greater than a basic coding unit size, the large block size being one of 32×32 and 64×64 and the basic coding unit size being 16×16, wherein the intra prediction is signaled for the at least a large block and the one or more processors are configured to:
decode a binary split signaling syntax element specifying whether the large block is further split into four equal sized sub-blocks; and
decode an intra prediction mode for said large block in the case where said binary split signaling syntax element specifies the large block is not further split;
otherwise in the case where said binary split signaling syntax element specifies the large block is further split:
decode for each sub-block, in the case where said sub-block is 32×32, a binary split signaling syntax element specifying whether said 32×32 sub-block is further split into four equal basic coding unit sized blocks and decode an intra prediction mode for said 32×32 subblock in the case where said binary split signaling syntax element specifies said 32×32 sub-block is not further split; and
decode for each sub-block, in the case where said sub-block is 16×16, a single spatial intra partition type, the single spatial intra partition type being determinable from among a plurality of spatial intra partition types, wherein the single spatial intra partition type selected from the plurality of spatial intra partition types is accompanied by at least one of (1) a single intra prediction type for the basic coding unit size which does not use a most probable intra prediction mode or (2) a single intra prediction type indicating the most probable intra prediction mode for the basic coding unit size.

2. The video decoder of claim 1 , wherein at least one of a spatial intra partition type table and an intra prediction mode table is pre-stored and used to decode the at least one large block.

3. The video decoder of claim 1 , wherein at least one of a spatial intra partition type table and an intra prediction mode table is received using one or more high level syntax elements and is used to decode the at least one large block.

4. A video encoder, comprising at least a memory and one or more processors, wherein the one or more processors are configured to:
encode picture data for at least a large block in a picture by determining that intra prediction is to be performed for the at least a large block, wherein the at least a large block has a large block size greater than a basic coding unit size, the large block size being one of 32×32 and 64×64 and the basic coding unit size being 16×16, wherein the intra prediction is signaled for the at least a large block and the one or more processors are configured to:
encode a binary split signaling syntax element specifying whether the large block is further split into four equal sized sub-blocks; and
encode an intra prediction mode for said large block in the case where said binary split signaling syntax element specifies the large block is not further split;
otherwise in the case where said binary split signaling syntax element specifies the large block is further split:
encode for each sub-block, in the case where said sub-block is 32×32, a binary split signaling syntax element specifying whether said 32×32 sub-block is further split into four equal basic coding unit sized blocks and encode an intra prediction mode for said 32×32 subblock in the case where said binary split signaling syntax element specifies said 32×32 sub-block is not further split; and
encode for each sub-block, in the case where said sub-block is 16×16, a single spatial intra partition type, the single spatial intra partition type being determinable from among a plurality of spatial intra partition types, wherein the single spatial intra partition type selected from the plurality of spatial intra partition types is accompanied by at least one of (1) a single intra prediction type for the basic coding unit size which does not use a most probable intra prediction mode or (2) a single intra prediction type indicating the most probable intra prediction mode for the basic coding unit size.

5. The video encoder of claim 4 , wherein at least one of a spatial intra partition type table and an intra prediction mode table is pre-stored and used to encode the at least one large block.

6. The video encoder of claim 4 , wherein at least one of a spatial intra partition type table and an intra prediction mode table is encoded using one or more high level syntax elements and is used to encode the at least one large block.

7. A decoding method comprising:
decoding picture data for at least a large block in a picture by determining that intra prediction is to be performed for the at least a large block, wherein the at least a large block has a large block size greater than a basic coding unit size, the large block size being one of 32×32 and 64×64 and the basic coding unit size being 16×16, wherein the intra prediction is signaled for the at least a large block by:
decoding a binary split signaling syntax element specifying whether the large block is further split into four equal sized sub-blocks; and
decoding an intra prediction mode for said large block responsive to said binary split signaling syntax element specifying that the large block is not further split;
responsive to said binary split signaling syntax element specifying the large block is further split, the method further comprises:
for said sub-block being 32×32, decoding for each sub-block a binary split signaling syntax element specifying whether the 32×32 sub-block is further split into four equal basic coding unit sized blocks and decoding an intra prediction mode for said 32×32 sub-block responsive to said binary split signaling syntax element specifying said 32×32 sub-block is not further split; and
for said sub-block being 16×16, decoding for each sub-block a single spatial intra partition type, the single spatial intra partition type being determinable from among a plurality of spatial intra partition types, wherein the single spatial intra partition type selected from the plurality of spatial intra partition types is accompanied by at least one of (1) a single intra prediction type for the basic coding unit size which does not use a most probable intra prediction mode or (2) a single intra prediction type indicating the most probable intra prediction mode for the basic coding unit size.

8. The decoding method of claim 7 , wherein at least one of a spatial intra partition type table and an intra prediction mode table is pre-stored and used to decode the at least one large block.

9. The decoding method of claim 7 , wherein at least one of a spatial intra partition type table and an intra prediction mode table is received using one or more high level syntax elements and is used to decode the at least one large block.

10. An encoding method comprising:
encoding picture data for at least a large block in a picture by determining that intra prediction is to be performed for the at least a large block, wherein the at least a large block has a large block size greater than a basic coding unit size, the large block size being one of 32×32 and 64×64 and the basic coding unit size being 16×16, wherein the intra prediction is signaled for the at least a large block by:
encoding a binary split signaling syntax element specifying whether the large block is

Assignees

• Interdigital Vc Holdings Inc

Inventors

• Zheng Yunfei
• Xu Qian
• Lu Xiaoan
• Yin Peng
• Sole Rojals Joel
• Abbas Adeel

Classifications

• H04N19/119

  Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks · CPC title

• H04N19/70

  characterised by syntax aspects related to video coding, e.g. related to compression standards · CPC title

• H04N19/176

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

• H04N19/11

  among a plurality of spatial predictive coding modes · CPC title

• H04N19/593 Primary

  involving spatial prediction techniques · CPC title