Arithmetic Coding Context Segmentation for Frequency Coefficients

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Arithmetic coding in video compression struggles with accurately determining contexts for image data, leading to decreased coding efficiency due to low frequency of updating symbol occurrence probabilities when contexts are classified in detail.

Innovation Solution

The method involves frequency-transforming image data, binarizing coefficients, and determining contexts common to multiple coefficients within segments to perform binary arithmetic coding and decoding, thereby increasing the frequency of updating probability information and improving coding efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If contexts are classified in detail for arithmetic coding, then coding precision is improved, but the frequency of updating symbol occurrence probability decreases

Engineering Contradiction:
Improvecoding precisionVSAvoidfrequency of updating symbol occurrence probability
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The patent divides the unit of processing into multiple segments, and for each segment, determines one or more contexts common to multiple coefficients. This segmentation allows the system to update probability information more frequently by processing multiple coefficients within each segment using shared contexts, thereby resolving the contradiction between detailed context classification and updating frequency.

Inventive Principle:
Principle #1Segmentation

2Adaptability or versatility

If the number of contexts is increased for detailed classification, then adaptability is improved, but device complexity increases

Engineering Contradiction:
Improveadaptability to image data characteristicsVSAvoidnumber of contexts
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges multiple coefficients within a segment to share common contexts. Instead of assigning separate contexts to each coefficient, multiple coefficients are grouped and processed using shared probability information, reducing the total number of contexts required while maintaining adaptability to image data characteristics.

Inventive Principle:
Principle #5Merging (Combining)

3Productivity

If contexts are classified in detail, then coding efficiency should be improved, but memory requirements increase

Engineering Contradiction:
Improvecoding efficiencyVSAvoidmemory requirements
Core Design Contradiction:
ProductivityVSQuantity of substance

Solution Approach 1:

By merging multiple coefficients into segments that share common contexts, the patent reduces the total number of probability tables that need to be stored in memory. This approach maintains coding efficiency through adequate context classification while significantly reducing memory requirements by eliminating redundant probability information.

Inventive Principle:
Principle #5Merging (Combining)

Data Source

PatentUS8687904B2Image coding method, image coding apparatus, image decoding method, image decoding apparatus, and image coding and decoding apparatus which include arithmetic coding or arithmetic decoding
Publication Date: 2014.04.01 SUN PATENT TRUST
  • US8687904B2 patent drawing
  • US8687904B2 patent drawing
  • US8687904B2 patent drawing

AI summary

An image coding method includes: frequency-transforming image data to generate a unit of processing in a frequency domain; binarizing a coefficient included in the unit of processing, to generate a binary signal; determining, as a context for a binary signal, one or more contexts common to a plurality of the coefficients included in a segment which includes the binarized coefficient, the segment being one of a plurality of segments obtained by dividing the unit of processing; performing binary arithmetic coding on the binary signal according to probability information corresponding to the determined context; and updating, based on the binary signal, the probability information corresponding to the determined context.