Video Decoder Coefficient Clipping for Cross-Component Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing video coding technologies face challenges in improving coding efficiency, enhancing image quality, and reducing processing resources and circuit scale, particularly in the context of cross component adaptive loop filtering (CCALF) processes.
Innovation Solution
The implementation of an encoder and decoder system that applies a CCALF process to luma and chroma components, involving coefficient clipping and combination, to enhance image quality and coding efficiency while reducing resource utilization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a CCALF process is applied to both luma and chroma components with coefficient clipping and combination, then image quality and coding efficiency are improved, but processing complexity and circuit scale increase
Solution Approach 1:
The patent combines the CCALF process for luma components with the ALF process for chroma components by adding their respective coefficient values. The luma CCALF coefficients and chroma ALF coefficients are summed to produce combined coefficients that are then used for chroma sample filtering. This merging approach allows both filtering processes to work together synergistically, improving image quality while managing processing complexity through a unified coefficient combination mechanism.
2Manufacturing precision
If coefficient clipping is applied in the CCALF and ALF processes, then manufacturing precision is improved, but device complexity increases
Solution Approach 1:
The patent applies clipping operations to constrain the coefficient values within specific ranges before combination. The luma CCALF coefficients are clipped to a first range and the chroma ALF coefficients are clipped to a second range. This parameter change approach ensures that extreme values are bounded, preventing numerical instability and improving coding efficiency while maintaining manageable circuit scale through standardized clipping operations.
3Manufacturing precision
If the CCALF and ALF processes are combined through coefficient addition, then image quality is enhanced, but processing resources increase
Solution Approach 1:
The patent performs clipping operations on the luma and chroma coefficients before adding them together. By preliminary clipping the coefficient values to appropriate ranges, the subsequent addition operation produces reliable results without requiring extensive post-processing or error correction. This preliminary action approach enhances image quality through proper coefficient combination while minimizing processing resources by avoiding unnecessary computational steps.
Data Source
AI summary
A decoder includes memory and a processor coupled to the memory and configured to: generate a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component; clip the first coefficient value such that the clipped first coefficient value is within a first range from −27 to 27−1; generate a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component; clip the second coefficient value such that the clipped second coefficient value is within a second range different from the first range; generate a third coefficient value by adding the clipped first coefficient value to the clipped second coefficient value; and generate a third reconstructed image sample of the chroma component using the third coefficient value.