Intra sub partitions for video encoding and decoding combined with multiple transform selection, matrix weighted intra prediction or multi-reference-line intra prediction

Patent metadata

Field	Value
Publication number	US-12401782-B2
Application number	US-202017781901-A
Country	US
Kind code	B2
Filing date	Nov 30, 2020
Priority date	Dec 5, 2019
Publication date	Aug 26, 2025
Grant date	Aug 26, 2025

Abstract

In an encoding apparatus or a decoding apparatus, an encoding method or decoding method combines various coding tools with intra sub partitioning mode in which a coding unit is split in multiple sub partitions. At least one embodiment particularly aims at the selection of primary transforms among a set of multiple transforms for video encoding or decoding of intra sub block partitions. At least one embodiment particularly aims at intra coding using Matrix-Based Intra Prediction mode combined with Intra Sub Partition mode. At least one embodiment particularly aims at intra coding using Multi-Reference-Line intra prediction mode combined with Intra Sub Partition mode.

First claim

The invention claimed is:

1. A method comprising:
obtaining information representative of a block of a video, wherein the block is coded using an intra-sub partition mode and the block is partitioned into sub partitions;
obtaining a syntax element representative of a reference line index, wherein the syntax element is signaled at the block level;
partitioning the block into sub partitions;
selecting a single reference line based on the reference line index;
for each of the sub partitions, predicting samples of the sub partitions based on applying a 2D matrix and 1D vector to a vector based on averaged samples of the single reference line;
applying an inverse transform to the sub partitions; and
decoding the block;
wherein the single reference line is selected from among multiple reference lines adjacent to a top line of the block or to a left column of the block and is used to predict all the sub partitions of the block.

2. A method comprising, for a block of a video coded using an intra-sub partition mode:
partitioning the block into sub partitions;
selecting a single reference line from among multiple reference lines adjacent to a top line of the block or to a left column of the block;
for each of the sub partitions, predicting samples of the sub partitions based on applying a 2D matrix and 1D vector to a vector based on averaged samples of the single reference line;
applying a transform to the sub partitions; and
encoding the block and signaling information, wherein the block is coded in intra-sub partition mode and the signaling information comprises a syntax element representative of a reference line index used for the predicting, wherein the syntax element is signaled at the block level;
wherein the single reference line is used to predict all the sub partitions of the block.

3. A video encoding apparatus comprising a processor configured to, for a block of a video coded using an intra-sub partition mode:
partition the block into sub partitions;
select a single reference line from among multiple reference lines adjacent to a top line of the block or to a left column of the block;
for each of the sub partitions, predict samples of the sub partitions based on applying a 2D matrix and 1D vector to a vector based on averaged samples of the single reference line;
apply a transform to the sub partitions; and
encode the block and signaling information, wherein the block is coded in intra-sub partition mode and the signaling information comprises a syntax element representative of a reference line index used for the predicting, wherein the syntax element is signaled at the block level;
wherein the single reference line is used to predict all the sub partitions of the block.

4. A video decoding apparatus comprising a processor configured to:
obtain information representative of a block of a video, wherein the block is coded using an intra-sub partition mode and the block is partitioned into sub partitions;
obtain a syntax element representative of a reference line index, wherein the syntax element is signaled at the block level;
partition the block into sub partitions;
select a single reference line based on the reference line index;
for each of the sub partitions, predict samples of the sub partitions based on applying a 2D matrix and 1D vector to a vector based on averaged samples of the single reference line;
apply an inverse transform to the sub partitions; and
decode the block;
wherein the single reference line is selected from among multiple reference lines adjacent to a top line of the block or to a left column of the block and is used to predict all the sub partitions of the block.

5. A non-transitory computer readable medium comprising program code instructions executable by a processor for implementing the method according to claim 1 .

6. A non-transitory computer readable medium comprising program code instructions executable by a processor for implementing the method according to claim 2 .

7. The method of claim 1 , wherein the type of partitioning is horizontal or vertical according to the value of the reference line index.

8. The method of claim 1 , wherein the type of partitioning is horizontal when the reference line index is equal to 1 and vertical when the reference line index is equal to 3.

9. The method of claim 1 , wherein the type of partitioning is horizontal when the reference line index is equal to 3 and vertical when the reference line index is equal to 1.

10. The method of claim 2 , wherein the type of partitioning is horizontal or vertical according to the value of the reference line index.

11. The method of claim 2 , wherein the type of partitioning is horizontal when the reference line index is equal to 1 and vertical when the reference line index is equal to 3.

12. The method of claim 2 , wherein the type of partitioning is horizontal when the reference line index is equal to 3 and vertical when the reference line index is equal to 1.

13. The apparatus of claim 3 , wherein the type of partitioning is horizontal or vertical according to the value of the reference line index.

14. The apparatus of claim 3 , wherein the type of partitioning is horizontal when the reference line index is equal to 1 and vertical when the reference line index is equal to 3.

15. The apparatus of claim 3 , wherein the type of partitioning is horizontal when the reference line index is equal to 3 and vertical when the reference line index is equal to 1.

16. The apparatus of claim 4 , wherein the type of partitioning is horizontal or vertical according to the value of the reference line index.

17. The apparatus of claim 4 , wherein the type of partitioning is horizontal when the reference line index is equal to 1 and vertical when the reference line index is equal to 3.

18. The apparatus of claim 4 , wherein the type of partitioning is horizontal when the reference line index is equal to 3 and vertical when the reference line index is equal to 1.

Assignees

• Interdigital Ce Patent Holdings Sas

Inventors

• Leleannec Fabrice
• Naser Karam
• Bordes Philippe
• Poirier Tangi
• GALPIN Franck
• Rath Gagan
• Robert Antoine

Classifications

• 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

• H04N19/157

  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

• H04N19/12

  Selection from among a plurality of transforms or standards, e.g. selection between discrete cosine transform [DCT] and sub-band transform or selection between H.263 and H.264 · CPC title

• H04N19/11

  among a plurality of spatial predictive coding modes · CPC title