Motion compensation considering out-of-boundary conditions in video coding

Patent metadata

Field	Value
Publication number	US-12452445-B2
Application number	US-202418774854-A
Country	US
Kind code	B2
Filing date	Jul 16, 2024
Priority date	Jan 18, 2022
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

Methods, apparatuses, and non-transitory computer-readable storage media are provided for video coding. In one method, a decoder derives a first and a second reference pictures for a current coding block; the decoder derives a first and a second predictor samples based on a motion vector associated with the first reference picture using a motion compensation process from the first reference picture; the decoder determines whether the first and the second predictor samples are out-of-boundary (OOB), and in response to determining the first or the second predictor sample is OOB, the decoder replaces the first or the second predictor sample that is OOB with a first or a second alternative predictor sample; and the decoder generates the final prediction sample by averaging sample values of the first predictor sample and the second predictor sample.

First claim

What is claimed is:

1. A method for decoding a bi-prediction coding block, comprising:
deriving, by a decoder, a first reference picture for a current coding block;
deriving, by the decoder, a first predictor sample based on a motion vector associated with the first reference picture using a motion compensation process from the first reference picture;
determining, by the decoder, whether the first predictor sample is out-of-boundary (OOB), and in response to determining the first predictor sample is OOB, replacing, by the decoder, the first predictor sample with a first alternative predictor sample;
deriving, by the decoder, a second reference picture for the current coding block;
deriving, by the decoder, a second predictor sample based on a motion vector associated with the second reference picture using a motion compensation process from the second reference picture;
determining, by the decoder, whether the second predictor sample is out-of-boundary (OOB), and in response to determining the second predictor sample is OOB, replacing, by the decoder, the second predictor sample with a second alternative predictor sample; and
generating a final prediction sample by averaging sample values of the first predictor sample and the second predictor sample.

2. The method of claim 1 , wherein replacing the first predictor sample with the first alternative predictor sample comprises:
setting the first alternative predictor sample as the second predictor sample.

3. The method of claim 1 , wherein replacing the second predictor sample with the second alternative predictor sample comprises:
setting the second alternative predictor sample as the first predictor sample.

4. An apparatus, comprising:
one or more processors; and
a memory configured to store instructions executable by the one or more processors and a bitstream; wherein the one or more processors, upon execution of the instructions, are configured to perform operations with the bitstream, the operations comprising:
deriving a first reference picture for a current coding block;
deriving a first predictor sample based on a motion vector associated with the first reference picture using a motion compensation process from the first reference picture;
determining whether the first predictor sample is out-of-boundary (OOB), and in response to determining the first predictor sample is OOB, replacing the first predictor sample with a first alternative predictor sample;
deriving a second reference picture for the current coding block;
deriving a second predictor sample based on a motion vector associated with the second reference picture using a motion compensation process from the second reference picture;
determining whether the second predictor sample is out-of-boundary (OOB), and in response to determining the second predictor sample is OOB, replacing the second predictor sample with a second alternative predictor sample; and
generating a final prediction sample by averaging sample values of the first predictor sample and the second predictor sample.

5. The apparatus of claim 4 , wherein replacing the first predictor sample with the first alternative predictor sample comprises:
setting the first alternative predictor sample as the second predictor sample.

6. The apparatus of claim 4 , wherein replacing the second predictor sample with the second alternative predictor sample comprises:
setting the second alternative predictor sample as the first predictor sample.

7. A non-transitory computer-readable storage medium for storing computer-executable instructions and a bitstream, when the computer-executable instructions executed by one or more computer processors, cause the one or more computer processors to receive a bitstream, and perform operations with the bitstream, the operations comprising:
deriving, by a decoder, a first reference picture for a current coding block;
deriving, by the decoder, a first predictor sample based on a motion vector associated with the first reference picture using a motion compensation process from the first reference picture;
determining, by the decoder, whether the first predictor sample is out-of-boundary (OOB), and in response to determining the first predictor sample is OOB, replacing, by the decoder, the first predictor sample with a first alternative predictor sample;
deriving, by the decoder, a second reference picture for the current coding block;
deriving, by the decoder, a second predictor sample based on a motion vector associated with the second reference picture using a motion compensation process from the second reference picture;
determining, by the decoder, whether the second predictor sample is out-of-boundary (OOB), and in response to determining the second predictor sample is OOB, replacing, by the decoder, the second predictor sample with a second alternative predictor sample; and
generating a final prediction sample by averaging sample values of the first predictor sample and the second predictor sample.

8. The non-transitory computer-readable storage medium of claim 7 , wherein replacing the first predictor sample with the first alternative predictor sample comprises:
setting the first alternative predictor sample as the second predictor sample.

9. The non-transitory computer-readable storage medium of claim 7 , wherein replacing the second predictor sample with the second alternative predictor sample comprises:
setting the second alternative predictor sample as the first predictor sample.

Assignees

• Beijing Dajia Internet Information Tech Co Ltd

Inventors

• Chen Yi-Wen
• Xiu Xiaoyu
• Kuo Che-Wei
• Jhu Hong-Jheng
• Chen Wei
• Yan Ning
• Wang Xianglin
• Yu Bing

Classifications

• H04N19/577

  Motion compensation with bidirectional frame interpolation, i.e. using B-pictures · CPC title

• H04N19/176

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

• H04N19/159

  Prediction type, e.g. intra-frame, inter-frame or bidirectional frame prediction · CPC title

• H04N19/105 Primary

  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

• H04N19/132

  Sampling, masking or truncation of coding units, e.g. adaptive resampling, frame skipping, frame interpolation or high-frequency transform coefficient masking · CPC title