CABAC Significance Map Scanning for Parallel Video Coding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing video compression techniques, such as H.264 and HEVC, face challenges in parallel processing due to dependencies between elements in the same scanning line during context model selection for significance maps, which limits their efficiency in encoding and decoding video data.

Innovation Solution

The proposed solution involves choosing context models for elements in a significance map based on neighboring elements from other scanning lines, eliminating dependencies within the same scanning line, and using pre-determined or adaptable scanning patterns to facilitate parallel processing in video encoding and decoding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If context models are selected based on neighboring elements in the same scanning line, then coding precision is improved through better adaptation, but processing speed deteriorates due to sequential dependencies

Engineering Contradiction:
Improvecoding precisionVSAvoidprocessing speed
Core Design Contradiction:
Measurement precisionVSSpeed

Solution Approach 1:

The patent divides the significance map into multiple scanning lines and processes them independently in parallel. By selecting context models based on neighboring elements from other scanning lines rather than the same scanning line, the patent creates independent processing segments that eliminate sequential dependencies within each scanning line, enabling parallel processing while maintaining adaptive context model selection.

Inventive Principle:
Principle #1Segmentation

2Productivity

If adaptive context model selection is implemented, then compression efficiency is improved, but device complexity increases

Engineering Contradiction:
Improvecompression efficiencyVSAvoiddevice complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent applies different context model selection strategies to different scanning lines based on their specific characteristics. By adapting context models locally to each scanning line's neighboring elements from other lines, the patent achieves better compression efficiency while managing complexity through localized rather than universal adaptation.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent pre-determines scanning patterns and context model selection rules before processing the significance map. This preliminary preparation of scanning patterns and context model configurations reduces the computational complexity during actual encoding/decoding operations while maintaining adaptive compression efficiency.

Inventive Principle:
Principle #10Preliminary action

3Ease of manufacture

If sequential processing of scanning lines is used, then implementation simplicity is maintained, but productivity decreases

Engineering Contradiction:
Improveimplementation simplicityVSAvoidproductivity
Core Design Contradiction:
Ease of manufactureVSProductivity

Solution Approach 1:

The patent segments the significance map processing into independent scanning line units that can be processed in parallel. Each scanning line is treated as an independent processing unit with its own context model selection based on neighboring elements from other lines, enabling parallel execution while maintaining relatively simple implementation of each individual unit.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from one-dimensional sequential processing of scanning lines to two-dimensional parallel processing by utilizing spatial relationships across different scanning lines. By selecting context models from neighboring elements in other scanning lines, the patent introduces a dimensional approach that enables parallel processing without significantly increasing implementation complexity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS8953690B2Method and system for processing video data
Publication Date: 2015.02.10 GOOGLE TECHNOLOGY HOLDINGS LLC
  • US8953690B2 patent drawing
  • US8953690B2 patent drawing
  • US8953690B2 patent drawing

AI summary

In various embodiments, a significance map of a matrix of video data coefficients is encoded or decoded using context-based adaptive binary arithmetic coding (CABAC). The significance map scanned line-by-line along a scanning pattern. Each line may be a vertical, horizontal, or diagonal section of the scanning pattern. Context models for each element processed in a particular line are chosen based on values of neighboring elements that are not in the line. The neighboring elements may be limited to those contained within one or two other scanning lines. Avoiding reliance on neighbors that are in the same scanning line facilitates parallel processing.