HEVC CABAC Absolute-3 Coding with Truncated EG0 for Throughput
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High bit-rate encoding and decoding in video coding standards like HEVC using CABAC face significant throughput performance issues, consuming substantial processing resources and time, especially with high bit-rate cases and large Absolute-3 values.
Innovation Solution
Implementing a method that involves arithmetic decoding and encoding of transform coefficients using k-th order Exp-Golomb coding, and adapting coding techniques such as Golomb-Rice and Exponential-Golomb coding based on Rice parameter values and block sizes to enhance throughput, including the use of truncated EG0 tables for high throughput modes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of information
If CABAC is used to compress TQCs without loss, then compression efficiency is improved, but processing time and computational complexity increase significantly
Solution Approach 1:
The patent segments the TQC coding process into multiple passes: a first pass using simplified Golomb-Rice coding for quick encoding, and a second pass using full CABAC for enhanced compression. This segmentation allows the system to achieve good compression ratios while maintaining lower computational complexity and faster processing speeds compared to using CABAC alone.
2Manufacturing precision
If high bit-rate encoding is performed with large Absolute-3 values, then encoding precision is improved, but throughput performance deteriorates
Solution Approach 1:
The patent implements dynamic switching between Golomb-Rice coding and CABAC based on the Absolute-3 value magnitude and bit-rate conditions. When Absolute-3 values are large and bit-rate is high, the system dynamically selects Golomb-Rice coding to maintain throughput performance. When precision requirements are higher and values are smaller, it switches to CABAC. This dynamic adaptation resolves the contradiction between encoding precision and throughput performance.
3Loss of information
If context adaptive coding is used for all symbols, then compression ratio is improved, but device complexity increases
Solution Approach 1:
The patent applies different coding methods to different regions of the TQC data based on local characteristics. Golomb-Rice coding is applied to coefficients with larger Absolute-3 values where context adaptation provides less benefit, while CABAC is applied to coefficients with smaller values where context adaptation is more effective. This local differentiation reduces overall device complexity while maintaining good compression ratios.
Data Source
AI summary
A system utilizing a high throughput coding mode for CABAC in HEVC is described. The system may include an electronic device configured to obtain a block of data to be encoded using an arithmetic based encoder; to generate a sequence of syntax elements using the obtained block; to compare an Absolute-3 value of the sequence or a parameter associated with the Absolute-3 value to a preset value; and to convert the Absolute-3 value to a codeword using a first code or a second code that is different than the first code, according to a result of the comparison.