Luma-Chroma Separated Coding Trees with Split Constraints for Lower Latency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing video coding technologies, such as HEVC, face challenges in managing the data dependency and latency issues between luma and chroma components due to separate tree structures, leading to increased buffer requirements and processing delays.
Innovation Solution
The method involves constraining data dependency between luma and chroma tree structures by ensuring they are mutually inclusive, allowing data dependency only when splitting is the same or absent in both trees, and using flags to control further splitting based on ancestor node splits.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If separate partition trees are used for luma and chroma components, then coding flexibility is improved, but data dependency and latency between components increase
Solution Approach 1:
The patent divides the chroma block partitioning process into independent segments that can be processed separately from luma partitioning. By allowing chroma to have its own partition tree with independent split decisions, the system achieves segmentation of processing tasks, reducing data dependency while maintaining coding flexibility through separate optimization of luma and chroma structures.
2Adaptability or versatility
If separate partition trees are used for luma and chroma components, then coding flexibility is improved, but buffer requirements increase
Solution Approach 1:
The patent applies preliminary action by establishing constraints on chroma partitioning based on luma partitioning results before actual encoding begins. The chroma partition tree is built with predetermined constraints that prevent excessive buffer allocation, allowing the system to prepare processing paths in advance while limiting resource consumption through pre-defined partitioning rules.
3Productivity
If cross-colour component prediction mode is allowed, then chroma coding efficiency is improved, but complexity of managing data dependency increases
Solution Approach 1:
The patent applies local quality by enabling cross-colour component prediction only in specific local regions where luma and chroma partitioning structures align favorably. Rather than uniformly applying the prediction mode across all blocks, the system selectively activates it in areas where it provides benefit while maintaining simpler processing elsewhere, thus improving chroma coding efficiency without uniformly increasing complexity.
Data Source
AI summary
A method and apparatus for block partition are disclosed. If a cross-colour component prediction mode is allowed, the luma block and the chroma block are partitioned into one or more luma leaf blocks and chroma leaf blocks. If a cross-colour component prediction mode is allowed, whether to enable an LM (Linear Model) mode for a target chroma leaf block is determined based on a first split type applied to an ancestor chroma node of the target chroma leaf block and a second split type applied to a corresponding ancestor luma node. According to another method, after the luma block and the chroma block are partitioned using different partition tress, determine whether one or more exception conditions to allow an LM for a target chroma leaf block are satisfied when the chroma partition tree uses a different split type, a different partition direction, or both from the luma partition tree.