Reduced Context Register for Arithmetic Coding

Solution Overview

Problem

Current video compression techniques face challenges in efficiently decoding high-resolution video streams over limited bandwidth channels, requiring effective context handling in arithmetic coding to reduce resource utilization and improve timing in decoders.

Innovation Solution

The implementation of a reduced size context coefficient register in video coding using efficient context handling in arithmetic coding, which determines a scan order distance for context coefficient values and reads corresponding values from a register, allowing for efficient decoding of video streams by reducing the size of the context coefficient register to one less than the maximal scan order distance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a full-size context coefficient register is used to store all decoded coefficients for arithmetic coding, then decoding accuracy is improved, but resource utilization increases and timing performance deteriorates

Engineering Contradiction:

Improvedecoding accuracyVSAvoidresource utilization

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the context coefficient storage by maintaining only the necessary recent coefficients in a reduced-size register rather than storing all coefficients. The context coefficient register is sized to hold only the maximum scan order distance minus one coefficient, dividing the storage burden and accessing only relevant segments of coefficient data needed for accurate arithmetic coding decoding.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent extracts only the essential context coefficients needed for decoding from the full set of decoded coefficients. By identifying and storing only the coefficients within the maximum scan order distance, the system extracts the critical subset of data required for maintaining decoding accuracy while discarding redundant storage of older coefficients that are no longer needed.

Inventive Principle:

Principle #2Taking out (Extraction)

2Measurement precision

If a full-size context coefficient register is used to store all decoded coefficients for arithmetic coding, then decoding accuracy is improved, but timing performance deteriorates

Engineering Contradiction:

Improvedecoding accuracyVSAvoidtiming performance

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The patent segments the context coefficient storage by maintaining only the necessary recent coefficients in a reduced-size register rather than storing all coefficients. The context coefficient register is sized to hold only the maximum scan order distance minus one coefficient, dividing the storage burden and accessing only relevant segments of coefficient data needed for accurate arithmetic coding decoding.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent extracts only the essential context coefficients needed for decoding from the full set of decoded coefficients. By identifying and storing only the coefficients within the maximum scan order distance, the system extracts the critical subset of data required for maintaining decoding accuracy while discarding redundant storage of older coefficients that are no longer needed.

Inventive Principle:

Principle #2Taking out (Extraction)

3Reliability

If context coefficient values are stored for the entire coefficient matrix, then context accuracy is improved, but device complexity increases

Engineering Contradiction:

Improvecontext accuracyVSAvoidregister size

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent segments the context coefficient storage by maintaining only the necessary recent coefficients in a reduced-size register rather than storing all coefficients. The context coefficient register is sized to hold only the maximum scan order distance minus one coefficient, dividing the storage burden and accessing only relevant segments of coefficient data needed for accurate arithmetic coding decoding.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent extracts only the essential context coefficients needed for decoding from the full set of decoded coefficients. By identifying and storing only the coefficients within the maximum scan order distance, the system extracts the critical subset of data required for maintaining decoding accuracy while discarding redundant storage of older coefficients that are no longer needed.

Inventive Principle:

Principle #2Taking out (Extraction)

Data Source

PatentEP3958565B1Efficient context handling in arithmetic coding

Publication Date: 2024.09.18 GOOGLE LLC

Figure 1
Figure 2
Figure 3

AI summary

Efficient context handling in arithmetic coding includes identifying a scan order for a current block and entropy decoding a current entropy coded transform coefficient from the current block. The entropy decoding includes determining, based on the scan order, a first scan order distance between a scan order location corresponding to the current entropy coded transform coefficient and a scan order location corresponding to a first context coefficient, identifying a first context coefficient value from a first location in a context coefficient register, the first location corresponding to the first scan order distance, wherein the context coefficient register is a reduced size context coefficient register, and entropy decoding the current entropy coded transform coefficient based on the first context coefficient value.