Rice Parameter Derivation for High Bit-Depth Transform Coefficients
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing video coding standards face challenges in accurately determining Rice parameters for high bit-depth video coding due to limitations in the derivation process, particularly when transform coefficients are near the borders of a transform block, leading to reduced compression efficiency.
Innovation Solution
A method for updating a coefficient statistic value based on the encoding procedure used for each transform coefficient, considering context-based and absolute value encoding, to enhance the accuracy of Rice parameter derivation, thereby improving coding efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single derivation process is used for all transform coefficients, then the device complexity is reduced, but the manufacturing precision of Rice parameter selection deteriorates
Solution Approach 1:
The patent divides the transform block into multiple regions (e.g., border regions and interior regions) and applies different derivation processes to each region. Specifically, coefficients near block borders use one derivation method while interior coefficients use another, allowing optimized accuracy for each region without uniformly increasing complexity across the entire block.
Solution Approach 2:
The patent implements location-dependent Rice parameter derivation where the derivation process varies based on the spatial position of transform coefficients within the block. Border coefficients receive specialized handling with different statistical updates compared to interior coefficients, ensuring locally optimized parameter selection that accounts for position-specific characteristics.
2Manufacturing precision
If multiple derivation processes are used for different transform coefficients, then the manufacturing precision of Rice parameter selection is improved, but the device complexity increases
Solution Approach 1:
The patent introduces dynamic adaptation in the derivation process by maintaining separate coefficient statistic values for different regions and selectively applying derivation methods based on coefficient location. The system dynamically chooses which derivation process to apply based on the spatial position of each coefficient, optimizing accuracy without requiring all possible derivation processes to be active simultaneously throughout the entire block.
3Ease of operation
If coefficients near block borders are processed with the same derivation process as interior coefficients, then the ease of operation is maintained, but the measurement precision of Rice parameter derivation deteriorates
Solution Approach 1:
The patent performs preliminary classification of transform coefficients based on their spatial location before applying derivation processes. By pre-identifying border coefficients versus interior coefficients and assigning them to different processing categories, the system prepares the data structure in advance to enable location-optimized derivation without adding complex real-time decision-making during the actual parameter calculation.
Data Source
AI summary
A method of decoding video data comprises updating a coefficient statistic value based on one or more transform coefficients of a transform block (TB), wherein updating the coefficient statistic value comprises, for each respective transform coefficient of the one or more transform coefficients of the TB: performing a derivation process to determine a temporary value, wherein the derivation process is determined based at least in part on which encoding procedure of a plurality of encoding procedures is used to encode the respective transform coefficient, the plurality of encoding procedures including a context-based procedure for encoding the respective transform coefficient and encoding the respective transform coefficient as an absolute value; and setting the coefficient statistic value as an average of the coefficient statistic value and the temporary value; determining a history value based on the coefficient statistic value; determining a Rice parameter for a specific transform coefficient of the TB.