Backward Compatible Codec Neutral Color Preservation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing single-layer backward compatible codecs struggle to preserve neutral colors accurately, leading to color distortion and shifts, especially in highly saturated images.

Innovation Solution

The method involves building a dynamic 3D mapping table from reference images of different dynamic ranges, computing content color and neutral color matrices, and using weighting factors to solve multiple-channel multiple regression coefficients, ensuring neutral color preservation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If conventional single-layer backward compatible codecs are used, then backward compatibility is maintained, but neutral color accuracy deteriorates leading to color distortion and shifts

Engineering Contradiction:

Improvebackward compatibilityVSAvoidneutral color accuracy

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent segments the color space into neutral color regions and non-neutral color regions. By separately processing neutral colors through dedicated neutral color preservation logic while maintaining conventional processing for other colors, the system achieves both backward compatibility and improved neutral color accuracy. This segmentation allows the codec to handle different color types with different processing strategies.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies local quality by implementing region-specific processing where neutral colors receive specialized treatment through adjusted color matrices and saturation control, while non-neutral colors use standard processing. This localized approach to color processing ensures that neutral colors are preserved with high accuracy without compromising the overall backward compatibility of the codec for other color regions.

Inventive Principle:

Principle #3Local quality

2Device complexity

If conventional color processing is used, then processing simplicity is maintained, but chroma distortion increases in highly saturated images

Engineering Contradiction:

Improveprocessing complexityVSAvoidchroma accuracy

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The patent implements partial action by applying complex neutral color preservation processing only to neutral color regions where it is most needed, rather than applying it uniformly to all colors. This selective approach reduces the overall computational burden while still achieving the goal of minimizing chroma distortion in highly saturated images through targeted processing of affected color regions.

Inventive Principle:

Principle #16Partial or excessive action

Data Source

PatentUS20250175625A1Neutral color preservation for single-layer backward compatible codec

Publication Date: 2025.05.29 DOLBY LABORATORIES LICENSING CORP

AI summary

Novel methods and systems for processing a single-layer backward compatible codec with multiple-channel multiple regression coefficients either provided in or pointed to in metadata such that the coefficients have been biased to prevent a shift in neutral colors. Pseudo neutral color patches are used along with a saturation weighting factor to bias the coefficients.