Sub-prediction unit motion vector prediction using spatial and/or temporal motion information

Patent metadata

Field	Value
Publication number	US-10271064-B2
Application number	US-201615176790-A
Country	US
Kind code	B2
Filing date	Jun 8, 2016
Priority date	Jun 11, 2015
Publication date	Apr 23, 2019
Grant date	Apr 23, 2019

Abstract

In one example, a device for decoding video data includes a memory configured to store video data and a video decoder configured to determine that a motion prediction candidate for a current block of video data indicates that motion information is to be derived for sub-blocks of the current block, in response to the determination: partition the current block into the sub-blocks, for each of the sub-blocks, derive motion information using motion information for at least two neighboring blocks, and decode the sub-blocks using the respective derived motion information.

First claim

What is claimed is:

1. A method of decoding video data, the method comprising:
determining that a value of a candidate index identifying a motion prediction candidate in a motion prediction candidate list for a current block of video data indicates that motion information is to be derived for sub-blocks of the current block;
in response to the determination:
determining the sub-blocks based on the candidate index and without decoding syntax elements, other than the candidate index, indicating that the current block is split into the sub-blocks;
for each of the sub-blocks, deriving motion information using an average of motion information for an above-neighboring block, a left-neighboring block, and a temporally neighboring block; and
decoding the sub-blocks using the respective derived motion information.

2. The method of claim 1 , wherein the above-neighboring block comprises an above-neighboring sub-block within the current block.

3. The method of claim 1 , wherein the left-neighboring block comprises a left-neighboring sub-block within the current block.

4. The method of claim 1 , wherein the above-neighboring block comprises an above-neighboring sub-block outside of the current block.

5. The method of claim 1 , wherein the left-neighboring block comprises a left-neighboring sub-block outside of the current block.

6. The method of claim 1 , wherein the temporally neighboring block comprises a block in a previously decoded picture that neighbors a block that is co-located with the current block in the previously decoded picture.

7. The method of claim 1 , wherein the above-neighboring, left-neighboring, and temporally neighboring blocks have sizes equal to or less than sizes of the sub-blocks.

8. The method of claim 1 , further comprising decoding data representative of a size of the sub-blocks.

9. The method of claim 8 , wherein decoding the data representative of the size of the sub-blocks comprises decoding the data in at least one of a slice header, a sequence parameter set (SPS), or a picture parameter set (PPS).

10. The method of claim 1 , wherein deriving the motion information comprises scaling motion information for the above-neighboring, left-neighboring, and temporally neighboring blocks to a common reference picture.

11. The method of claim 1 , wherein deriving the motion information comprises deriving a motion vector (MV) for each of the sub-blocks according to the following formula, where w i represents a horizontal weighting factor, w j represents a vertical weighting factor, O i represents a horizontal offset value, and O j represents a vertical offset value:
( MV x ,MV y )=((Σ i=0 2 MV xi +sign(Σ i=0 2 MV xi )*1)*43/128,(Σ i=0 2 MV yi +sign(−Σ i=0 2 MV yi )*1)*43/128)).

12. The method of claim 1 , further comprising adding the motion prediction candidate to the motion prediction candidate list.

13. The method of claim 1 , further comprising encoding the sub-blocks prior to decoding the sub-blocks, the method further comprising encoding data that identifies the motion prediction candidate for the current block.

14. The method of claim 1 , the method being executable on a wireless communication device, wherein the device comprises:
a memory configured to store the video data;
a processor configured to execute instructions to process the video data stored in the memory; and
a receiver configured to receive an encoded version of the video data.

15. The method of claim 14 , wherein the wireless communication device is a cellular telephone and the encoded video data is received by the receiver and modulated according to a cellular communication standard.

16. A device for decoding video data, the device comprising:
a memory comprising circuitry and configured to store video data; and
a video decoder comprising circuitry and configured to:
determine that a value of a candidate index identifying a motion prediction candidate in a motion prediction candidate list for a current block of the video data indicates that motion information is to be derived for sub-blocks of the current block;
in response to the determination:
determine the sub-blocks based on the candidate index and without decoding syntax elements, other than the candidate index, indicating that the current block is split into the sub-blocks;
for each of the sub-blocks, derive motion information using an average of motion information for an above-neighboring block, a left-neighboring block, and a temporally neighboring block; and
decode the sub-blocks using the respective derived motion information.

17. The device of claim 16 ,
wherein the above-neighboring sub-block comprises an above-neighboring sub-block within the current block or outside the current block, and
wherein the left-neighboring sub-block comprises a left-neighboring sub-block within the current block or outside the current block.

18. The device of claim 16 , wherein the video decoder is further configured to decode data representative of a size of the sub-blocks from at least one of a slice header, a sequence parameter set (SPS), or a picture parameter set (PPS).

19. The device of claim 16 , wherein the video decoder is further configured to scale motion information for the above-neighboring, left-neighboring, and temporally neighboring blocks to a common reference picture.

20. The device of claim 16 , further comprising a video encoder configured to encode the sub-blocks before the video decoder decodes the sub-blocks.

21. The device of claim 16 , wherein the device is a wireless communication device, further comprising:
a receiver configured to receive an encoded version of the video data.

22. The device of claim 21 , wherein the wireless communication device is a cellular telephone and the encoded video data is received by the receiver and modulated according to a cellular communication standard.

23. A device for decoding video data, the device comprising:
means for determining that a value of a candidate index identifying a motion prediction candidate in a motion prediction candidate list for a current block of video data indicates that motion information is to be derived for sub-blocks of the current block;
means for determining the sub-blocks based on the candidate index and without decoding syntax elements, other than the candidate index, indicating that the current block is split into the sub-blocks, in response to the determination;
means for deriving, for each of the sub-blocks, motion information using an average of motion information for an above-neighboring block, a left-neighboring block, and a temporally neighboring block in response to the determination; and
means for decoding the sub-blocks using the respective derived motion information in response to the determination.

24. The device of claim 23 ,
wherein the above-neighboring sub-block comprises an above-neighboring sub-block within the current block or outside the current block, and
wherein the left-neighboring sub-block comprises a left-neighboring sub-block within the current block or outside the current block.

25. The device of claim 23 , further comprising means for encoding the sub-blocks before the means for decoding decodes the sub-blocks.

26. A non-transitory computer-readable storage medium having stored thereon instructions that, when executed, cause a processor to:
determine that a value of a candidate index

Assignees

• Qualcomm Inc

Inventors

• Chien Wei-Jung
• Wang Xianglin
• Zhang Li
• Liu Hongbin
• Chen Jianle
• Karczewicz Marta

Classifications

• H04N19/70

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

• H04N19/61

  in combination with predictive coding · CPC title

• H04N19/52 Primary

  by predictive encoding · CPC title

• H04N19/51 Primary

  Motion estimation or motion compensation · CPC title

• H04N19/176

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