Video Transform Type Derivation for TIMD Merge Blocks

Solution Overview

Problem

The current inheritance of transform types in video coding systems like ECM 10 results in suboptimal outcomes due to the lack of correlation between the transform type of selected candidates and the current block, particularly in TIMD merge mode.

Innovation Solution

A method is introduced to decide whether to use the inherited transform type or a derived transform type based on conditions such as block size, transform unit size, and transform type diversity of neighboring blocks, allowing for a more correlated choice of transform type.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If transform type inheritance is applied in TIMD merge mode, then encoding time and bitrate are reduced, but transform accuracy deteriorates when candidate and current block have different residual characteristics

Engineering Contradiction:

Improveencoding timeVSAvoidtransform accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The transform type selection is made dynamic by introducing a decision mechanism that adapts to the current block's characteristics. The encoder evaluates residual characteristics and block properties to dynamically choose between inherited transform type and alternative transform types, rather than rigidly inheriting from candidates.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The transform type parameter is changed based on evaluated conditions. The system modifies the transform type selection by comparing residual characteristics and block properties, switching between inherited and alternative transform types to optimize coding efficiency for different block types.

Inventive Principle:

Principle #35Parameter changes

2Loss of information

If transform type inheritance is applied in TIMD merge mode, then bitrate is reduced, but transform accuracy deteriorates when candidate and current block have different residual characteristics

Engineering Contradiction:

ImprovebitrateVSAvoidtransform accuracy

Core Design Contradiction:

Loss of informationVSMeasurement precision

Solution Approach 1:

The transform type selection is made dynamic by introducing a decision mechanism that adapts to the current block's characteristics. The encoder evaluates residual characteristics and block properties to dynamically choose between inherited transform type and alternative transform types, rather than rigidly inheriting from candidates.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The transform type parameter is changed based on evaluated conditions. The system modifies the transform type selection by comparing residual characteristics and block properties, switching between inherited and alternative transform types to optimize coding efficiency for different block types.

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If transform type inheritance is applied, then device complexity is reduced, but encoding efficiency deteriorates due to suboptimal transform type selection

Engineering Contradiction:

Improvedevice complexityVSAvoidencoding efficiency

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The transform type parameter is changed based on evaluated conditions. The system modifies the transform type selection by comparing residual characteristics and block properties, switching between inherited and alternative transform types to optimize coding efficiency for different block types.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The system uses feedback from residual characteristic analysis to improve transform type selection. By evaluating the match between candidate and current block characteristics, the system provides feedback to the transform type selection process, avoiding suboptimal inherited choices.

Inventive Principle:

Principle #23Feedback

Data Source

PatentEP4676045A1Encoding/decoding video picture data

Publication Date: 2026.01.07 BEIJING XIAOMI MOBILE SOFTWARE CO LTD

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AI summary

The present disclosure relates to implicit transform type derivation that improves the current inheritance transform type method as defined in ECM and helps TIMD merge mode (or similar applicable modes) to implicitly replace transform types as inherited by the current inheritance transform type method by other transform type if certain conditions are fulfilled.