Video Encoder Quantization Matrix Switching for Transform-Adaptive Coding

Solution Overview

Problem

Existing video coding technologies face challenges in efficiently processing increasing amounts of digital video data, particularly in optimizing encoding and decoding processes to maintain image quality and reduce processing overhead.

Innovation Solution

An encoder and decoder system that dynamically applies a quantization matrix based on the performance of primary and secondary transforms, allowing for adaptive quantization and inverse quantization processes to improve encoding efficiency and subjective image quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a quantization matrix is applied to all blocks regardless of transform type, then encoding simplicity is maintained, but encoding efficiency and image quality deteriorate

Engineering Contradiction:

Improveencoding efficiencyVSAvoidencoding process complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The patent implements dynamic selection of quantization matrices based on the transform type applied to each block. The encoder adaptively chooses between different quantization matrices (e.g., first quantization matrix for primary transform only, second quantization matrix for primary and secondary transforms, third quantization matrix when transforms are skipped) according to the specific processing path taken for each block, thereby optimizing encoding efficiency without excessive complexity

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent applies different quantization matrices to different blocks based on their specific transform characteristics. Each block receives a quantization matrix appropriate to its processing path (primary transform only, primary and secondary transforms, or transforms skipped), ensuring optimal quality for each local region rather than applying a uniform approach to all blocks

Inventive Principle:

Principle #3Local quality

2Manufacturing precision

If different quantization matrices are used for different transform cases, then image quality improves, but processing complexity increases

Engineering Contradiction:

Improveimage qualityVSAvoidquantization process complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent implements dynamic selection of quantization matrices based on the transform type applied to each block. The encoder adaptively chooses between different quantization matrices (e.g., first quantization matrix for primary transform only, second quantization matrix for primary and secondary transforms, third quantization matrix when transforms are skipped) according to the specific processing path taken for each block, thereby optimizing encoding efficiency without excessive complexity

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The patent applies different quantization matrices to different blocks based on their specific transform characteristics. Each block receives a quantization matrix appropriate to its processing path (primary transform only, primary and secondary transforms, or transforms skipped), ensuring optimal quality for each local region rather than applying a uniform approach to all blocks

Inventive Principle:

Principle #3Local quality

3Manufacturing precision

If primary and secondary transforms are always applied, then frequency transformation completeness improves, but processing time and computational load increase

Engineering Contradiction:

Improvetransform completenessVSAvoidprocessing time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent implements conditional application of transforms based on block characteristics and content requirements. Instead of always applying both primary and secondary transforms, the encoder selectively applies transforms only when necessary to achieve acceptable quality, thereby reducing processing time and computational load while maintaining transform completeness where needed

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The patent dynamically determines whether to apply primary transform, secondary transform, or skip transforms based on the specific characteristics of each block. This adaptive approach allows the system to optimize between transform completeness and processing efficiency on a per-block basis, reducing unnecessary computational overhead

Inventive Principle:

Principle #15Dynamics

Data Source

PatentUS12513294B2Encoder, decoder, encoding method, and decoding method

Publication Date: 2025.12.30 PANASONIC INTELLECTUAL PROPERTY CORP OF AMERICA

AI summary

An encoder, includes: memory; and circuitry coupled to the memory, in which in a first encoding process, the circuitry quantizes a current block using a first quantization matrix in both of a first case where the circuitry performs primary transform and the circuitry does not perform secondary transform and a second case where the circuitry performs both the primary transform and the secondary transform, in a second encoding process, the circuitry quantizes the current block using a second quantization matrix in a third case where the circuitry performs primary transform and the circuitry does not perform secondary transform, and in a third encoding process, the circuitry quantizes the current block without using a quantization matrix in both of a fourth case where both the primary transform and the secondary transform are skipped and a fifth case where both the primary transform and the secondary transform are performed.