Method and apparatus for video coding

Patent metadata

Field	Value
Publication number	US-2020007864-A1
Application number	US-201816222626-A
Country	US
Kind code	A1
Filing date	Dec 17, 2018
Priority date	Jul 2, 2018
Publication date	Jan 2, 2020
Grant date	—

Abstract

Aspects of the disclosure provide method and apparatus for video encoding/decoding. In some examples, an apparatus for video decoding includes receiving circuitry and processing circuitry. The processing circuitry decodes prediction information for a block in a current picture that is a part of a coded video bitstream. The prediction information is indicative of an inter prediction mode. In response to the inter prediction mode, the processing circuitry constructs a candidate list of candidate motion vector predictors in a ranking order that are sorted based on statistics of motion information in a spatial neighboring region of the block. The processing circuitry then determines, a motion vector predictor from the candidate list following the ranking order, and reconstructs samples of the block according to motion information associated with the determined motion vector predictor.

First claim

1 . A method for video decoding in a decoder, comprising:
decoding prediction information for a current block in a current picture from a coded video bitstream, the prediction information being indicative of an inter prediction mode; scanning a line of blocks in a spatial neighboring region of the current block to collect statistics of motion information in the spatial neighboring region, the line of blocks including adjacent blocks to the current block and at least one non-adjacent block to the current block; constructing, in response to the inter prediction mode and if the current block satisfies at least one of a width requirement and a height requirement, a candidate list of candidate motion vector predictors in a ranking order that are sorted based on the statistics of the motion information in the spatial neighboring region of the current block; determining a motion vector predictor from the candidate list following the ranking order; and reconstructing at least a sample of the current block according to motion information associated with the determined motion vector predictor.

2 . The method of claim 1 , wherein the scanning comprises:
scanning neighboring blocks in the spatial neighboring region to collect the statistics of the motion information in the spatial neighboring region.

3 . The method of claim 1 , wherein the scanning comprises:
scanning minimum-size blocks in the spatial neighboring region to collect the statistics of the motion information in the spatial neighboring region.

4 . The method of claim 1 , wherein the scanning comprises:
scanning minimum-size blocks that are adjacent to the current block to collect the statistics of the motion information in the spatial neighboring region.

5 . The method of claim 1 , wherein
the scanning includes scanning first minimum-size blocks that are located in a left column next to the current block and are extended in a bottom-left direction; and the method further includes scanning second minimum-size blocks that are located in an upper row next to the current block and are extended in an above-right direction to collect the statistics of the motion information in the spatial neighboring region.

6 . The method of claim 1 , wherein
the scanning includes scanning first minimum-size blocks that are located in multiple left columns next to the current block and are extended in a bottom-left direction to collect the statistics of the motion information in the spatial neighboring region; and the method further includes scanning second minimum-size blocks that are located in multiple upper rows next to the current block and are extended in an above-right direction to collect the statistics of the motion information in the spatial neighboring region.

7 . The method of claim 1 , wherein the scanning comprises:
scanning representative minimum-size blocks respectively in grid units that are adjacent to the current block to collect the statistics of the motion information in the spatial neighboring region.

8 . The method of claim 1 , wherein
the scanning includes scanning first representative minimum-size blocks respectively in first grid units that are located in a left column next to the current block and are extended in a bottom-left direction to collect the statistics of the motion information in the spatial neighboring region; and the method further includes scanning second representative minimum-size blocks respectively in second grid units that are located in an upper row next to the second block and are extended in an above-right direction to collect the statistics of the motion information in the spatial neighboring region.

9 . The method of claim 1 , wherein
the scanning includes scanning first representative minimum-size blocks respectively in first grid units that are located in multiple left columns, including the line of blocks, next to the current block and are extended in a bottom-left direction to collect the statistics of the motion information in the spatial neighboring region; and the method further includes scanning second representative minimum-size blocks respectively in second grid units that are located in multiple upper rows next to the current block and are extended in an above-right direction to collect the statistics of the motion information in the spatial neighboring region.

10 . The method of claim 2 , further comprising:
constructing a histogram of the motion information in the spatial neighboring region according to the statistics; and sorting motion vector predictors from the spatial neighboring region into the ranking order according to the histogram.

11 . The method of claim 10 , further comprising:
constructing the histogram with bins corresponding to individual motion vectors.

12 . The method of claim 10 , further comprising:
constructing the histogram with bins corresponding to ranges of motion vectors.

13 . The method of claim 10 , further comprising:
selecting a portion of the sorted motion vector predictors based on rankings in the ranking order.

14 . (canceled)

15 . An apparatus for video decoding, comprising:
processing circuitry configured to:
decode prediction information for a current block in a current picture from a coded video bitstream, the prediction information being indicative of an inter prediction mode;
scan a line of blocks in a spatial neighboring region of the current block to collect statistics of motion information in the spatial neighboring region, the line of blocks including adjacent blocks to the current block and at least one non-adjacent block to the current block;
construct, in response to the inter prediction mode and if the current block satisfies at least one of a width requirement and a height requirement, a candidate list of candidate motion vector predictors in a ranking order that are sorted based on the statistics of the motion information in the spatial neighboring region of the current block;
determine a motion vector predictor from the candidate list following the ranking order; and
reconstruct at least a sample of the current block according to motion information associated with the determined motion vector predictor.

16 . The apparatus of claim 15 , wherein the processing circuitry is further configured to:
perform the scan on neighboring blocks in the spatial neighboring region to collect the statistics of the motion information in the spatial neighboring region.

17 . The apparatus of claim 6 , wherein the processing circuitry is further configured to:
perform the scan on minimum-size blocks in the spatial neighboring region to collect the statistics of the motion information in the spatial neighboring region.

18 . The apparatus of claim 16 , wherein the processing circuitry is further configured to:
construct a histogram of the motion information in the spatial neighboring region according to the statistics; and sort motion vector predictors from the spatial neighboring region into the ranking order according to the histogram.

19 . The apparatus of claim 18 , wherein the processing circuitry is further configured to:
select a portion of the sorted motion vector predictors based on rankings in the ranking order to construct the candidate list.

20 . (canceled)

Assignees

• Tencent America LLC

Inventors

• Li Guichun
• Xu Xiaozhong
• Li Xiang
• Liu Shan

Classifications

• H04N19/52 Primary

  by predictive encoding · CPC title

• H04N19/105

  Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction · CPC title

• H04N19/139

  Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability · CPC title

• H04N19/176

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

• H04N19/129 Primary

  Scanning of coding units, e.g. zig-zag scan of transform coefficients or flexible macroblock ordering [FMO] · CPC title