Method and device for processing video image

Patent metadata

Field	Value
Publication number	US-2020053384-A1
Application number	US-201916657226-A
Country	US
Kind code	A1
Filing date	Oct 18, 2019
Priority date	Oct 31, 2017
Publication date	Feb 13, 2020
Grant date	—

Abstract

Embodiments of the present disclosure disclose a video image processing method performed at a computing device, including: performing half pixel estimation on a predefined region of a target image frame to obtain an optimal half pixel location having a minimum rate distortion cost; dividing a surrounding area of the optimal half pixel location into four partitions; selecting, among the four partitions according to rate distortion costs respectively of four half pixel locations adjacent to the optimal half pixel location, a first partition used for quarter pixel estimation; performing quarter pixel estimation on the first partition according to the optimal half pixel location, to obtain an optimal quarter pixel location having a minimum rate distortion cost within the first partition; and performing motion compensation to the target image frame by using at least one of the optimal half pixel location and the optimal quarter pixel location as a motion estimation result.

First claim

What is claimed is:

1 . A video image processing method performed at a computing device having one or more processors and memory storing programs to be executed by the one or more processors, the method comprising:
obtaining a target image frame from a to-be-encoded video image and selecting a predefined integer pixel location in the target image frame; performing half pixel estimation on a predefined region of the target image frame including the predefined integer pixel location, to obtain an optimal half pixel location having a minimum rate distortion cost within the predefined region of the target image frame; dividing a surrounding area of the optimal half pixel location into four partitions; selecting, among the four partitions according to rate distortion costs respectively corresponding to four half pixel locations adjacent to the optimal half pixel location, a first partition used for quarter pixel estimation; performing quarter pixel estimation on the first partition according to the optimal half pixel location, to obtain an optimal quarter pixel location having a minimum rate distortion cost within the first partition; and performing motion compensation to the target image frame by using at least one of the optimal half pixel location and the optimal quarter pixel location as a motion estimation result.

2 . The method according to claim 1 , wherein the performing half pixel estimation on a predefined region of the target image frame including the predefined integer pixel location comprises:
obtaining four half pixel locations adjacent to the predefined integer pixel location, the four half pixel locations being four pixel locations: directly above, directly below, directly on the left side of, and directly on the right side of the predefined integer pixel location; calculating rate distortion costs for the predefined integer pixel location and the four half pixel locations; and determining that the optimal half pixel location is the predefined integer pixel location in a case that the predefined integer pixel location has a rate distortion cost lower than that of the four half pixel locations.

3 . The method according to claim 2 , wherein the dividing a surrounding area of the optimal half pixel location into four partitions comprises:
dividing a surrounding area of the optimal half pixel location into four partitions in a case that the predefined integer pixel location has a rate distortion cost lower than that of the four half pixel locations, each partition being obtained from an area defined by the predefined integer pixel location and two of the four half pixel locations.

4 . The method according to claim 1 , wherein the performing half pixel estimation on a predefined region of the target image frame including the predefined integer pixel location comprises:
obtaining four half pixel locations adjacent to the predefined integer pixel location, the four half pixel locations being four pixel locations: directly above, directly below, directly on the left side of, and directly on the right side of the predefined integer pixel location; calculating rate distortion costs for the predefined integer pixel location and the four half pixel locations; obtaining, in a case that a location corresponding to a first smallest rate distortion cost is a first one of the four half pixel locations, two half pixel locations adjacent to the first half pixel location in a same axial direction; obtaining a location corresponding to a second smallest rate distortion cost from the first half pixel location and the two half pixel locations adjacent to the first half pixel location; and determining, in a case that the location corresponding to the second smallest rate distortion cost is the first half pixel location, that the optimal half pixel location is the first half pixel location.

5 . The method according to claim 1 , wherein the performing half pixel estimation on a predefined region of the target image frame including the predefined integer pixel location comprises:
obtaining four half pixel locations adjacent to the predefined integer pixel location, the four half pixel locations being four pixel locations: directly above, directly below, directly on the left side of, and directly on the right side of the predefined integer pixel location; calculating rate distortion costs for the predefined integer pixel location and the four half pixel locations; obtaining, in a case that a location corresponding to a first smallest rate distortion cost is a first one of the four half pixel locations, two half pixel locations adjacent to the first half pixel location in a same axial direction; obtaining a location corresponding to a second smallest rate distortion cost from the first half pixel location and the two half pixel locations adjacent to the first half pixel location; and determining, in a case that the location corresponding to the second smallest rate distortion cost is one of the two half pixel locations adjacent to the first half pixel location, that the optimal half pixel location is the location corresponding to the second smallest rate distortion cost.

6 . The method according to claim 4 , wherein the dividing a surrounding area of the optimal half pixel location into four partitions comprises:
obtaining, in a case that the location corresponding to the second smallest rate distortion cost is the first half pixel location, a second half pixel location adjacent to the first half pixel location, the second half pixel location being a location on which no half interpolation is performed and one selected from the group consisting of four locations including: directly above, directly below, directly on the left side of, and directly on the right side of the first half pixel location; and dividing a surrounding area of the first half pixel location into four partitions, each partition being obtained from an area divided by the first half pixel location, the predefined integer pixel location, the two half pixel locations adjacent to the first half pixel location, and the second half pixel location.

7 . The method according to claim 5 , wherein the dividing a surrounding area of the optimal half pixel location into four partitions comprises:
obtaining, in a case that the location corresponding to the second smallest rate distortion cost is the one of the two half pixel locations adjacent to the first half pixel location, two fourth half pixel locations adjacent to the one of the two half pixel locations adjacent to the first half pixel location, the two fourth half pixel locations being pixel locations on which no interpolation is performed and that are two of the four pixel locations including: directly above, directly below, directly on the left side of, and directly on the right side of the third half pixel location; and dividing a surrounding area of the one of the two half pixel locations adjacent to the first half pixel location into four partitions, each partition being obtained from an area divided by the one of the two half pixel locations adjacent to the first half pixel location, two pixel locations that are adjacent to the one of the two half pixel locations adjacent to the first half pixel location and that are in the four half pixel locations, and the two fourth half pixel locations.

8 . The method according to claim 1 , wherein the performing quarter pixel estimation on the first partition according to the optimal half pixel location, to obtain an optimal quarter pixel location having a minimum rate distortion cost within the first partition comprises:
performing quarter interpolation at three surrounding locations in the first partition according to the optimal half pixel location, to obtain three quarter pixel

Assignees

• Tencent Tech Shenzhen Co Ltd

Inventors

• Zhang Hongshun

Classifications

• H04N19/523 Primary

  with sub-pixel accuracy · 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

• H04N19/567 Primary

  Motion estimation based on rate distortion criteria · CPC title

• H04N19/119

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

• H04N19/533

  Motion estimation using multistep search, e.g. two-dimensional [2D]-log search or one-at-a-time search [OTS] · CPC title