NON-SQUARE BLOCKS IN VIDEO CODING

• US 20190313108A1
• Filed: 04/04/2019
• Published: 10/10/2019
• Est. Priority Date: 04/05/2018
• Status: Abandoned Application

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Zhang, Li, Zhang, Kai, Chien, Wei-Jung, Karczewicz, Marta
• Application Number:
  US16/375,665
• Publication Number:
  US 20190313108A1
• Time in Patent Office: Days
• CPC Class Codes: H04N 19/119 Adaptive subdivision aspects, e.g. subdivision of a picture into rectangular or non-rectangular coding blocks
• CPC Class Codes: H04N 19/122 Selection of transform size, e.g. 8x8 or 2x4x8 DCT; Selection of sub-band transforms of varying structure or type
• CPC Class Codes: H04N 19/129 Scanning of coding units, e.g. zig-zag scan of transform coefficients or flexible macroblock ordering [FMO]
• CPC Class Codes: H04N 19/136 Incoming video signal characteristics or properties
• CPC Class Codes: H04N 19/157 Assigned coding mode, i.e. the coding mode being predefined or preselected to be further used for selection of another element or parameter
• CPC Class Codes: H04N 19/159 Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/18 the unit being a set of transform coefficients
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 19/649 the transform being applied to non rectangular image segments
• CPC Class Codes: H04N 19/91 Entropy coding, e.g. variable length coding [VLC] or arithmetic coding
• CPC Class Codes: H04N 19/96 Tree coding, e.g. quad-tree coding

Abstract

Techniques are described for decoding and encoding video data utilizing non-square coefficient groups (CGs). A coefficient group includes a plurality of coefficient values for a block of coefficient values. In one or more examples, the CGs that form at least part of the block of coefficient values are non-square shaped.

Claims

1. A method of decoding video data, the method comprising:

determining, for a current block that is non-square, coefficient values for one or more non-square coefficient groups, wherein the one or more non-square coefficient groups together form at least part of a block of coefficient values, and the coefficient values for the one or more non-square coefficient groups form at least a part of the coefficient values for the block of coefficient values;

transforming the coefficient values of the block of coefficient values into residual samples of a residual block; and

reconstructing the current block based on a prediction block and the residual block.

2. The method of claim 1, wherein a width or height of the current block is not a multiple of 4.

3. The method of claim 1, wherein determining the coefficient values for the one or more non-square coefficient groups comprises:

determining coefficient values for a first non-square coefficient group of the one or more non-square coefficient groups; and

determining coefficient values for a second non-square coefficient group of the one or more non-square coefficient groups,

wherein a size of the first non-square coefficient group and a size of the second non-square coefficient group are different.

4. The method of claim 1, wherein the one or more non-square coefficient groups form a first part of the block of coefficient values, the method further comprising:

determining, for the current block, coefficient values for one or more square coefficient groups, wherein the one or more square coefficient groups together form a second part of the block of coefficient values.

5. The method of claim 1, further comprising:

receiving information indicative of a manner in which the block of coefficient values is partitioned,

wherein determining, for the current block, the coefficient values for one or more non-square coefficient groups comprises determining, for the current block, the coefficient values for one or more non-square coefficient groups based on the information indicative of the manner in which the block of coefficient values is partitioned.

6. The method of claim 1, wherein the current block is partitioned based on one of a quad-tree-binary-tree (QTBT) partitioning or a triple tree partitioning.

7. The method of claim 1, further comprising:

determining that the current block is of a particular color component,

wherein determining, for the current block, the coefficient values for one or more non-square coefficient groups comprises determining, for the current block, the coefficient values for one or more non-square coefficient groups, responsive to the current block being of the particular color component.

8. The method of claim 1, further comprising:

determining that the current block is of a particular block shape,

wherein determining, for the current block, the coefficient values for one or more non-square coefficient groups comprises determining, for the current block, the coefficient values for one or more non-square coefficient groups, responsive to the current block being of the particular block shape.

9. The method of claim 1, further comprising:

determining that the current block is of a particular size,

wherein determining, for the current block, the coefficient values for one or more non-square coefficient groups comprises determining, for the current block, the coefficient values for one or more non-square coefficient groups, responsive to the current block being of the particular size.

18. The method of claim 1, further comprising:

determining that the current block is of a particular size,

wherein partitioning the block of coefficient values into the one or more non-square coefficient groups comprises partitioning the block of coefficient values into the one or more non-square coefficient groups, responsive to the current block being of the particular size.

10. A method of encoding video data, the method comprising:

determining residual samples of a residual block based on a difference between a current block that is non-square and a prediction block;

transforming the residual samples of the residual block into a block of coefficient values;

partitioning the block of coefficient values into one or more non-square coefficient groups, wherein the one or more non-square coefficient groups together form at least part of the block of coefficient values, and coefficient values for the one or more non-square coefficient groups form at least a part of the coefficient values for the block of coefficient values; and

signaling information indicative of the coefficient values for the one or more square coefficient groups.

11. The method of claim 10, wherein a width or height of the current block is not a multiple of 4.

12. The method of claim 10, wherein partitioning the block of coefficient values into the one or more non-square coefficient groups comprises:

partitioning the block of coefficient values into a first non-square coefficient group of the one or more non-square coefficient groups; and

partitioning the block of coefficient values into a second non-square coefficient group of the one or more non-square coefficient groups,

wherein a size of the first non-square coefficient group and a size of the second non-square coefficient group are different.

13. The method of claim 10, wherein the one or more non-square coefficient groups form a first part of the block of coefficient values, the method further comprising:

partitioning the block of coefficient values into the one or more square coefficient groups, wherein the one or more square coefficient groups together form a second part of the block of coefficient values.

14. The method of claim 10, further comprising:

signaling information indicative of a manner in which the block of coefficient values is partitioned.

15. The method of claim 10, further comprising:

partitioning the current block based on one of a quad-tree-binary-tree (QTBT) partitioning or a triple tree partitioning.

16. The method of claim 10, further comprising:

determining that the current block is of a particular color component,

wherein partitioning the block of coefficient values into the one or more non-square coefficient groups comprises partitioning the block of coefficient values into the one or more non-square coefficient groups, responsive to the current block being of the particular color component.

17. The method of claim 10, further comprising:

determining that the current block is of a particular block shape,

wherein partitioning the block of coefficient values into the one or more non-square coefficient groups comprises partitioning the block of coefficient values into the one or more non-square coefficient groups, responsive to the current block being of the particular block shape.

19. A device for decoding video data, the device comprising:

a memory configured to store a prediction block; and

a video decoder comprising at least one of fixed-function or programmable circuitry, wherein the video decoder is configured to;

determine, for a current block that is non-square, coefficient values for one or more non-square coefficient groups, wherein the one or more non-square coefficient groups together form at least part of a block of coefficient values, and the coefficient values for the one or more non-square coefficient groups form at least a part of the coefficient values for the block of coefficient values;

transform the coefficient values of the block of coefficient values into residual samples of a residual block; and

reconstruct the current block based on the prediction block stored in memory and the residual block.

20. The device of claim 19, wherein a width or height of the current block is not a multiple of 4.

21. The device of claim 19, wherein to determine the coefficient values for the one or more non-square coefficient groups, the video decoder is configured to:

determine coefficient values for a first non-square coefficient group of the one or more non-square coefficient groups; and

determine coefficient values for a second non-square coefficient group of the one or more non-square coefficient groups,

wherein a size of the first non-square coefficient group and a size of the second non-square coefficient group are different.

22. The device of claim 19, wherein the one or more non-square coefficient groups form a first part of the block of coefficient values, and wherein the video decoder is configured to:

determine, for the current block, coefficient values for one or more square coefficient groups, wherein the one or more square coefficient groups together form a second part of the block of coefficient values.

23. The device of claim 19, wherein the video decoder is configured to:

receive information indicative of a manner in which the block of coefficient values is partitioned,

wherein to determine, for the current block, the coefficient values for one or more non-square coefficient groups, the video decoder is configured to determine, for the current block, the coefficient values for one or more non-square coefficient groups based on the information indicative of the manner in which the block of coefficient values is partitioned.

24. The device of claim 19, wherein the current block is partitioned based on one of a quad-tree-binary-tree (QTBT) partitioning or a triple tree partitioning.

25. The device of claim 19, wherein the video decoder is configured to:

determine that the current block is of a particular color component,

wherein to determine, for the current block, the coefficient values for one or more non-square coefficient groups, the video decoder is configured to determine, for the current block, the coefficient values for one or more non-square coefficient groups, responsive to the current block being of the particular color component.

26. The device of claim 19, wherein the video decoder is configured to:

determine that the current block is of a particular block shape,

wherein to determine, for the current block, the coefficient values for one or more non-square coefficient groups, the video decoder is configured to determine, for the current block, the coefficient values for one or more non-square coefficient groups, responsive to the current block being of the particular block shape.

27. The device of claim 19, wherein the video decoder is configured to:

determine that the current block is of a particular size,

wherein to determine, for the current block, the coefficient values for one or more non-square coefficient groups, the video decoder is configured to determine, for the current block, the coefficient values for one or more non-square coefficient groups, responsive to the current block being of the particular size.

28. The device of claim 19, wherein the device comprises a wireless communication device, further comprising a receiver configured to receive encoded video data.

29. The device of claim 28, wherein the wireless communication device comprises a telephone handset and wherein the receiver is configured to demodulate, according to a wireless communication standard, a signal comprising the encoded video data.

30. A computer-readable storage medium storing instructions that when executed cause one or more processors of a device for decoding video data to:

determine, for a current block that is non-square, coefficient values for one or more non-square coefficient groups, wherein the one or more non-square coefficient groups together form at least part of a block of coefficient values, and the coefficient values for the one or more non-square coefficient groups form at least a part of the coefficient values for the block of coefficient values;

transform the coefficient values of the block of coefficient values into residual samples of a residual block; and

reconstruct the current block based on a prediction block and the residual block.