Affine Motion Compensation Bandwidth Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing video encoding and decoding technologies face challenges in minimizing memory bandwidth usage, leading to increased power consumption and processing time due to the retrieval of reference samples for predicting video data blocks.
Innovation Solution
A video coder imposes constraints to reduce memory bandwidth by determining the necessary bandwidth for a current block and selectively modifying the motion compensation method based on whether the determined bandwidth satisfies a threshold, using affine motion compensation to predict samples of the current block, and determining the chroma motion vector based on a subset of luma motion vectors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If reference samples are retrieved from memory for predicting current block samples, then prediction accuracy is improved, but memory bandwidth consumption increases
Solution Approach 1:
The patent extracts only the necessary reference samples from memory based on the current block's position and motion vector information, rather than retrieving all possible reference samples. This selective extraction reduces memory bandwidth consumption while maintaining prediction accuracy by obtaining only the required data.
Solution Approach 2:
The patent implements partial action by retrieving a limited set of reference samples sufficient for affine motion compensation prediction, rather than excessive amounts of reference data. The method determines the minimum necessary reference samples based on block boundaries and motion characteristics, reducing overall memory bandwidth usage.
2Measurement precision
If more reference samples are retrieved for motion compensation, then prediction quality is improved, but processing time increases
Solution Approach 1:
The patent extracts only the essential reference samples needed for accurate motion compensation prediction, avoiding unnecessary retrieval and processing of excess data. This selective approach reduces processing time while maintaining prediction quality by focusing computational resources on critical samples.
Solution Approach 2:
The method applies partial action by retrieving a sufficient but limited number of reference samples for motion compensation. The patent determines the optimal subset of reference samples based on block position and motion vectors, achieving good prediction quality without the processing overhead of retrieving all possible reference data.
3Measurement precision
If affine motion compensation is applied to all sub-blocks, then prediction accuracy is improved, but memory bandwidth consumption increases
Solution Approach 1:
The patent applies local quality by using affine motion compensation selectively for specific sub-blocks where it provides the most benefit, rather than uniformly applying it to all sub-blocks. The method determines which sub-blocks require affine prediction based on local motion characteristics and block position, optimizing the balance between prediction accuracy and memory bandwidth consumption.
Solution Approach 2:
The patent segments the current block into multiple sub-blocks and applies different prediction strategies to different segments. By dividing the block and selectively applying affine motion compensation to specific segments based on their characteristics, the method reduces overall memory bandwidth consumption while maintaining prediction accuracy where needed.
Data Source
AI summary
An example method includes obtaining values of luma motion vectors for a plurality of luma sub-blocks of a current block of the video data selected for coding using affine motion compensation; determining, based on values of luma motion vectors of a sub-set of the plurality of luma sub-blocks, a value of a chroma motion vector for a chroma sub-block that corresponds to the plurality of luma sub-blocks; predicting, using affine motion compensation, respective samples of each luma sub-block of the plurality of luma sub-blocks based on respective values of the luma motion vectors; and predicting, using affine motion compensation, sample the chroma sub-block based on the value of the chroma motion vector.