Joint CCALF Video Coding for Chroma Filtering Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing video coding technologies face challenges in improving coding efficiency, enhancing image quality, and reducing circuit scale and processing resources.
Innovation Solution
Implementing a cross component adaptive loop filtering (CCALF) process that applies adaptive loop filtering to both luma and chroma components, clipping the coefficient values, and combining them to enhance image quality and coding efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If adaptive loop filtering is applied to both luma and chroma components separately, then image quality is improved, but processing resources and circuit scale increase
Solution Approach 1:
The patent combines separate CCALF processing for luma and chroma components into a unified JC-CCALF process. The loop filter simultaneously processes both components by generating a first coefficient from luma samples and a second coefficient from chroma samples, then combining them into a third coefficient for joint filtering. This merging reduces circuit scale and processing resources while maintaining image quality improvement.
2Productivity
If cross component adaptive loop filtering is implemented, then coding efficiency is improved, but processing complexity increases
Solution Approach 1:
The patent segments the CCALF processing into distinct coefficient generation stages: a first coefficient from luma samples, a second coefficient from chroma samples, and a combined third coefficient. This segmentation allows the complex JC-CCALF process to be broken down into manageable steps that improve coding efficiency while controlling processing complexity through structured computation.
Solution Approach 2:
The patent applies parameter changes by clipping coefficient values to specific ranges during the filtering process. The first and second coefficients are clipped to predetermined ranges before being combined, which simplifies the processing requirements and reduces computational complexity while maintaining the coding efficiency benefits of cross-component filtering.
3Productivity
If coefficient values are clipped to predetermined ranges, then processing resources are reduced, but filtering precision may be limited
Solution Approach 1:
The patent changes the parameter ranges of coefficient values by clipping them to predetermined minimum and maximum values. This parameter transformation reduces processing resources by limiting the dynamic range of values that need to be handled, while the clipping operation is designed to maintain sufficient filtering precision for practical video coding applications.
Data Source
AI summary
An encoder includes circuitry and memory. The circuitry, in operation, generates a first coefficient value by applying a CCALF (cross component adaptive loop filtering) process to a first reconstructed image sample of a luma component. The circuitry generates a second coefficient value by applying an ALF (adaptive loop filtering) process to a second reconstructed image sample of a chroma component. The circuitry generates a third coefficient value by adding the first coefficient value to the second coefficient value, and encodes a third reconstructed image sample of the chroma component using the third coefficient value. The circuitry determines a first parameter having the same value for Cb component and Cr component of the chroma component. The circuitry determines, using the first parameter, a model of entropy coding from a plurality of models. The circuitry performs, using the model, the entropy coding of a second parameter of the CCALF process.