Method and apparatus for video encoding and decoding based on illumination compensation

Patent metadata

Field	Value
Publication number	US-12477147-B2
Application number	US-202418438781-A
Country	US
Kind code	B2
Filing date	Feb 12, 2024
Priority date	Oct 5, 2017
Publication date	Nov 18, 2025
Grant date	Nov 18, 2025

Abstract

Methods and apparatuses for video coding and decoding are provided. The method of video encoding includes determining a set of parameters for illumination compensation associated with a first motion compensated reference block of a block in a picture of a video based on a function of a set of samples of the first motion compensated reference block and a set of samples of a second motion compensated reference block of the block, processing a prediction of the block based on the set of parameters, the prediction being associated with the first motion compensated reference block and encoding the block based on the processed prediction. A bitstream formatted to include encoded data, a computer-readable storage medium and a computer program product are also described.

First claim

The invention claimed is:

1 . A method of video decoding comprising:
obtaining a first motion compensated reference block of a current block in a picture and a second motion compensated reference block of the current block; determining a first set of illumination compensation linear model parameters of a first illumination compensation linear model associated with the first motion compensated reference block and a second set of illumination compensation linear model parameters of a second illumination compensation linear model associated with the second motion compensated reference block based on a minimization according to various sets of illumination compensation linear model parameters of a difference between the first motion compensated reference block transformed by the first illumination compensation linear model and the second motion compensated reference block transformed by the second illumination compensation linear model; applying the first illumination compensation linear model with the first set of illumination compensation linear model parameters to the first motion compensated reference block to obtain a first illumination compensated reference block and applying the second illumination compensation linear model with the second set of illumination compensation linear model parameters to the second motion compensated reference block to obtain a second illumination compensated reference block; combining the first illumination compensated reference block and the second illumination compensated reference block to obtain a final predictor for the current block; and decoding the current block based on the final predictor.

2 . The method of claim 1 , wherein a metric representing the difference is used in the minimization, the metric being one of a sum of a squared difference and a sum of an absolute difference, the squared difference and the absolute difference being between samples of the first motion compensated reference block transformed by the first illumination compensation linear model and samples of the second motion compensated reference block transformed by the second illumination compensation linear model.

3 . The method of claim 1 , wherein at least one flag is included in video data comprising the picture, the at least one flag indicating whether illumination compensation is to be applied to at least one block of the picture, to a slice of the picture, to the picture or to the encoded video.

4 . A non-transitory computer readable storage medium having stored thereon instructions for causing one or more processors to implement the method of claim 1 .

5 . An apparatus for video decoding comprising electronic circuitry adapted for:
obtaining a first motion compensated reference block of a current block in a picture and a second motion compensated reference block of the current block; determining a first set of illumination compensation linear model parameters of a first illumination compensation linear model associated with the first motion compensated reference block and a second set of illumination compensation linear model parameters of a second illumination compensation linear model associated with the second motion compensated reference block based on a minimization according to various sets of illumination compensation linear model parameters of a difference between the first motion compensated reference block transformed by the first illumination compensation linear model and the second motion compensated reference block transformed by the second illumination compensation linear model; applying the first illumination compensation linear model with the first set of illumination compensation linear model parameters to the first motion compensated reference block to obtain a first illumination compensated reference block and applying the second illumination compensation linear model with the second set of illumination compensation linear model parameters to the second motion compensated reference block to obtain a second illumination compensated reference block; combining the first illumination compensated reference block and the second illumination compensated reference block to obtain a final predictor for the current block; and decoding the current block based on the final predictor.

6 . The apparatus of claim 5 , wherein a metric representing the difference is used in the minimization, the metric being one of a sum of a squared difference and a sum of an absolute difference, the squared difference and the absolute difference being between samples of the first motion compensated reference block transformed by the first illumination compensation linear model and samples of the second motion compensated reference block transformed by the second illumination compensation linear model.

7 . The apparatus of claim 5 , wherein at least one flag is included in video data comprising the picture, the at least one flag indicating whether illumination compensation is to be applied to at least one block of the picture, to a slice of the picture, to the picture or to the encoded video.

8 . A method of video encoding comprising:
obtaining a first motion compensated reference block of a current block in a picture and a second motion compensated reference block of the current block; determining a first set of illumination compensation linear model parameters of a first illumination compensation linear model associated with the first motion compensated reference block and a second set of illumination compensation linear model parameters of a second illumination compensation linear model associated with the second motion compensated reference block based on a minimization according to various sets of illumination compensation linear model parameters of a difference between the first motion compensated reference block transformed by the first illumination compensation linear model and the second motion compensated reference block transformed by the second illumination compensation linear model; applying the first illumination compensation linear model with the first set of illumination compensation linear model parameters to the first motion compensated reference block to obtain a first illumination compensated reference block and applying the second illumination compensation linear model with the second set of illumination compensation linear model parameters to the second motion compensated reference block to obtain a second illumination compensated reference block; combining the first illumination compensated reference block and the second illumination compensated reference block to obtain a final predictor for the current block; and encoding the current block based on the final predictor.

9 . The method of claim 8 , wherein a metric representing the difference is used in the minimization, the metric being one of a sum of a squared difference and a sum of an absolute difference, the squared difference and the absolute difference being between samples of the first motion compensated reference block transformed by the first illumination compensation linear model and samples of a second motion compensated reference block transformed by the second illumination compensation linear model.

10 . The method of claim 8 , wherein at least one flag is included in video data comprising the picture, the at least one flag indicating whether illumination compensation is to be applied to at least one block of the picture, to a slice of the picture, to the picture or to the encoded video.

11 . A non-transitory computer readable storage medium having stored thereon instructions for causing one or more processors to implement the method of claim 8 .

12 . An apparatu

Assignees

• Interdigital Vc Holdings Inc

Inventors

• Bordes Philippe
• GALPIN Franck
• Racape Fabien

Classifications

• H04N19/583

  Motion compensation with overlapping blocks · CPC title

• H04N19/176

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

• H04N19/513

  Processing of motion vectors · CPC title

• H04N19/577 Primary

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