MPM List Generation for Video Coding Reference Lines
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing video coding standards, such as HEVC, face inefficiencies in generating and signaling most probable modes (MPMs) lists for intra prediction, particularly when dealing with adjacent and non-adjacent reference lines, which affects coding efficiency and complexity.
Innovation Solution
The proposed method involves determining candidate intra prediction modes, generating an MPM list based on the reference line used for encoding and whether an intra sub-partition (ISP) mode is enabled, and signaling a reference line index to optimize the MPM list generation for both zero and non-zero reference lines in the Versatile Video Coding (VVC) standard.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a unified MPM list generation method is used for all reference lines, then the processing complexity is reduced, but the coding efficiency deteriorates due to inability to optimize for specific reference line characteristics
Solution Approach 1:
The patent segments the reference lines into two distinct categories: adjacent reference lines (reference line index 0) and non-adjacent reference lines (reference line index > 0). Different MPM list generation methods are applied to each category, allowing optimization for each type while maintaining manageable complexity through systematic differentiation.
Solution Approach 2:
The patent applies different MPM list generation strategies tailored to specific reference line types. For adjacent reference lines, one generation method is used, while for non-adjacent reference lines, a different method is applied. This local optimization ensures that each reference line type receives the most appropriate processing, improving overall coding efficiency without uniformly increasing complexity.
2Productivity
If different MPM list generation methods are used for adjacent and non-adjacent reference lines, then coding efficiency is improved, but the processing complexity increases
Solution Approach 1:
The patent implements dynamic MPM list generation that adapts based on the reference line index. The system automatically selects the appropriate generation method (unified or differentiated) based on the specific coding context, allowing flexibility to optimize coding efficiency while managing complexity through conditional logic rather than rigid fixed structures.
3Loss of information
If traditional MPM list generation is used without reference line consideration, then the signaling overhead is reduced, but the video compression performance deteriorates
Solution Approach 1:
The patent performs preliminary analysis of reference line characteristics before generating the MPM list. By examining the reference line index and adjacent block modes in advance, the system prepares an optimized MPM list that anticipates the most probable modes, thereby improving compression performance without significantly increasing signaling overhead through efficient flag usage.
Solution Approach 2:
The patent changes the parameters used for MPM list generation based on the reference line index. When the reference line index indicates a non-adjacent reference line, the system adjusts the candidate mode selection and MPM list composition accordingly, optimizing video compression performance for different reference line scenarios while maintaining manageable signaling overhead through targeted parameter adjustments.
Data Source
AI summary
A method of signaling an intra prediction mode used to encode a current block in an encoded video bitstream using at least one processor includes determining a plurality of candidate intra prediction modes; generating a most probable mode (MPM) list using the plurality of candidate intra prediction modes; signaling a reference line index indicating a reference line used to encode the current block from among a plurality of reference lines including an adjacent reference line and a plurality of non-adjacent reference lines; and signaling an intra mode index indicating the intra prediction mode, wherein the MPM list is generated based on the reference line used to encode the current block and whether an intra sub-partition (ISP) mode is enabled.