Selective Block Motion Compensation for Lower Decoding Overhead

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing image decoding technologies using overlapped block motion compensation (OBMC) face increased memory bandwidth and calculation requirements due to its application without considering block sizes and prediction directions, leading to reduced encoding performance.

Innovation Solution

An image decoding device that applies OBMC based on specific conditions such as block sizes, prediction directions, and types of adjacent blocks, including determining whether to apply OBMC, changing prediction methods, and adjusting weight coefficients to optimize memory usage and calculations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If OBMC is applied regardless of block size or prediction direction, then prediction accuracy is improved, but memory bandwidth and calculation requirements increase

Engineering Contradiction:

Improveprediction accuracyVSAvoidmemory bandwidth

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent changes the application parameters of OBMC by introducing determination conditions based on block size and prediction direction type. The system dynamically adjusts whether to apply OBMC or not, and when to apply it, based on these parameters. This resolves the contradiction by avoiding unnecessary OBMC applications that increase memory bandwidth while preserving accuracy where beneficial.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent makes the OBMC application dynamic rather than static. Instead of applying OBMC uniformly to all blocks, the system dynamically determines applicability based on real-time analysis of block size and prediction direction. This dynamic approach allows the system to adapt to different coding scenarios and optimize the balance between prediction accuracy and memory bandwidth usage.

Inventive Principle:

Principle #15Dynamics

2Measurement precision

If OBMC is applied regardless of block size or prediction direction, then prediction accuracy is improved, but calculation requirements increase

Engineering Contradiction:

Improveprediction accuracyVSAvoidcalculation efficiency

Core Design Contradiction:

Measurement precisionVSProductivity

Solution Approach 1:

The patent changes the application parameters of OBMC by introducing determination conditions based on block size and prediction direction type. The system dynamically adjusts whether to apply OBMC or not, and when to apply it, based on these parameters. This resolves the contradiction by avoiding unnecessary OBMC applications that increase calculation requirements while preserving accuracy where beneficial.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies OBMC partially rather than excessively. Instead of uniformly applying OBMC to all blocks regardless of suitability, the system selectively applies it only to blocks that meet the determination conditions (specific block sizes and prediction direction combinations). This partial application reduces unnecessary calculations while maintaining accuracy improvements where OBMC is truly beneficial.

Inventive Principle:

Principle #16Partial or excessive action

3Loss of energy

If OBMC is applied to reduce memory bandwidth, then encoding performance improves, but decoding complexity increases

Engineering Contradiction:

Improvememory bandwidth reductionVSAvoiddecoding complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

Inventive Principle:

Principle #35Parameter changes

4Use of energy by moving object

If OBMC is selectively applied based on determination conditions, then memory bandwidth and calculation requirements are reduced, but prediction accuracy may deteriorate

Engineering Contradiction:

Improvememory bandwidthVSAvoidprediction accuracy

Core Design Contradiction:

Use of energy by moving objectVSMeasurement precision

Solution Approach 1:

The patent applies local quality by treating different blocks differently based on their specific characteristics (size and prediction direction). Instead of a uniform approach, the system identifies local conditions where OBMC is beneficial and applies it only there. This resolves the contradiction by concentrating OBMC applications in regions where they provide maximum benefit while avoiding them where they would be detrimental, thus optimizing both memory bandwidth and prediction accuracy.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS12363340B2Image decoding device with block motion compensator and determination mechanism

Publication Date: 2025.07.15 KDDI CORP

AI summary

An image decoding device includes: a motion compensation predictor configured to generate a prediction image signal of a prediction target block based on information about a motion vector in a unit of the block and a reference frame; an overlapped block motion compensator carrying out an overlapped block motion compensation process of correcting the prediction image signal of the prediction target block by subjecting the prediction image signal of the prediction target block and a prediction image signal generated based on information about a motion vector and a reference frame of an adjacent block of the prediction target block to weighted averaging; and a determinator determining whether the overlapped block motion compensation process is applied to the prediction target block or not. The determinator determines application of the overlapped block motion compensation process to the prediction target block, when unidirectional prediction is applied to the adjacent block.