Adaptive Overlapped Block Prediction for Video Coding

Solution Overview

Problem

Current video compression techniques face challenges in efficiently encoding and decoding video streams due to variations in block sizes and prediction parameters, leading to suboptimal prediction accuracy and increased data redundancy.

Innovation Solution

The method involves adaptive overlapped block prediction, where overlap regions in a current block are identified and predicted using a weighted function based on both current and adjacent block prediction parameters, allowing for optimized prediction by adapting the size of each overlap region according to the difference between prediction parameters.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If variable block sizes are used for encoding video blocks, then encoding flexibility and adaptability to different video content are improved, but prediction accuracy deteriorates due to inconsistencies at block boundaries

Engineering Contradiction:

Improveencoding flexibilityVSAvoidprediction accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The current block is divided into multiple overlap regions, each corresponding to a different adjacent block. This segmentation allows different prediction methods to be applied to different regions, resolving the conflict between variable block size flexibility and prediction accuracy at boundaries.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different prediction strategies are applied to different regions of the current block based on their proximity to adjacent blocks. Regions closer to adjacent blocks use predictions from those adjacent blocks, while central regions use predictions from current block parameters, optimizing local prediction quality throughout the block.

Inventive Principle:

Principle #3Local quality

2Measurement precision

If prediction parameters are adjusted to improve prediction accuracy at block boundaries, then data redundancy increases due to the need to encode additional prediction information

Engineering Contradiction:

Improveprediction accuracyVSAvoiddata redundancy

Core Design Contradiction:

Measurement precisionVSLoss of substance

Solution Approach 1:

Instead of applying complex adaptive prediction to the entire block, the method applies adjacent block predictions only to specific overlap regions at block boundaries. This partial application reduces the amount of additional prediction information that needs to be encoded while still improving boundary prediction accuracy.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The overlap regions serve as intermediaries between current block predictions and adjacent block predictions. By using these intermediate regions to blend predictions, the method achieves smoother transitions and better accuracy without requiring extensive encoding of prediction parameters throughout the entire block.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Measurement precision

If overlap regions are used to improve prediction at block boundaries, then encoding complexity increases due to additional processing steps

Engineering Contradiction:

Improveprediction accuracyVSAvoidencoding complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The current block is divided into multiple overlap regions, each corresponding to a different adjacent block. This segmentation allows different prediction methods to be applied to different regions, resolving the conflict between variable block size flexibility and prediction accuracy at boundaries.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different prediction strategies are applied to different regions of the current block based on their proximity to adjacent blocks. Regions closer to adjacent blocks use predictions from those adjacent blocks, while central regions use predictions from current block parameters, optimizing local prediction quality throughout the block.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS10567793B2Adaptive overlapped block prediction in variable block size video coding

Publication Date: 2020.02.18 GOOGLE LLC

AI summary

Encoding frames of a video stream may include encoding a current block of a current frame, generating a base prediction block for the current block based on current prediction parameters associated with the current block, identifying adjacent prediction parameters used for encoding previously encoded adjacent blocks that are adjacent to the current block. At least one side of the current block is adjacent to two or more of the previously encoded adjacent blocks. The encoding may include determining overlap regions in the current block, each of the overlap regions corresponding to a respective previously encoded adjacent block, generating an overlapped prediction of pixel values for each of the overlap regions according to a weighted function of the base prediction and a prediction based on the adjacent prediction parameters. The weighted function may be based on a difference between the current prediction parameters and the adjacent prediction parameters.