Intra Prediction Candidate Lists for Efficient Image Decoding
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The increasing demand for high-resolution and high-quality images leads to higher transmission and storage costs due to the increased amount of information, necessitating a more efficient image compression technique.
Innovation Solution
An image decoding method and apparatus that improves coding efficiency by deriving an intra prediction mode candidate list from multiple intra prediction types, considering reference line indices and reference samples, and applying a unified intra prediction mode list construction process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple intra prediction types are used to improve coding efficiency, then compression efficiency is improved, but device complexity increases
Solution Approach 1:
The patent merges multiple intra prediction types (MPM mode and non-MPM mode) into a unified intra prediction mode candidate list. The decoder constructs a single candidate list that includes both MPM candidates (derived from neighboring block modes) and non-MPM candidates (other available intra prediction modes), eliminating the need for separate processing paths and reducing device complexity while maintaining compression efficiency.
Solution Approach 2:
The unified intra prediction mode candidate list serves multiple functions: it contains both MPM and non-MPM candidates, supports various intra prediction types (planar, DC, directional modes), and works for different block configurations. This multi-functional approach replaces multiple specialized data structures and processing logic, reducing overall system complexity.
2Manufacturing precision
If separate processing is used for MPM and non-MPM modes, then prediction accuracy is maintained, but coding complexity increases
Solution Approach 1:
The patent combines MPM mode processing and non-MPM mode processing into a single unified flow. Both modes contribute candidates to the same intra prediction mode candidate list, and the same derivation and selection processes are applied regardless of whether candidates come from MPM or non-MPM sources. This unified approach maintains prediction accuracy while significantly reducing coding complexity.
3Manufacturing precision
If high-resolution images are transmitted, then image quality is improved, but transmission cost increases
Solution Approach 1:
The patent extracts and exploits spatial redundancy within high-resolution images by using intra prediction. Instead of transmitting all pixel data for high-resolution images, the encoder transmits only the intra prediction mode index and residual data, leveraging the correlation between neighboring pixels to reconstruct high-quality images with fewer transmitted bits, thereby reducing transmission cost.
Solution Approach 2:
The unified intra prediction mode candidate list merges multiple prediction strategies to improve compression efficiency for high-resolution images. By combining MPM and non-MPM candidates in a single list and using efficient mode selection, the patent achieves better compression ratios for high-resolution content, reducing the transmission cost while maintaining image quality.
Data Source
AI summary
A method for decoding an image by a decoding device according to the present document comprises the steps of: receiving prediction-related information of a current block; deriving an intra prediction type of the current block on the basis of the prediction-related information; forming an intra prediction mode candidate list of the current block on the basis of intra prediction modes of blocks neighboring the current block; deriving an intra prediction mode of the current block on the basis of the intra prediction mode candidate list; and deriving reference samples of the current block on the basis of the intra prediction type and the intra prediction mode, and deriving a prediction sample on the basis of the reference samples.