Color Conversion Apparatus Gamut Expansion via Inversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Color gamut compression occurs when images are printed, leading to a mismatch between additive color display and subtractive color printing, resulting in images that cannot be accurately decompressed when displayed on a scanner, especially for film photos which require conformity to the original colors.
Innovation Solution
A color conversion apparatus that reads original images with discrete color gamut representation and converts color coordinates from a first color space to a second color space, optimizing the color reproduction range to match the output device's maximum capabilities, using techniques like pseudo-inverse matrices and ICC profiles to ensure accurate color representation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If color gamut compression is performed to match printed image colors with display colors, then color difference is reduced, but the image cannot be decompressed back to the original color gamut and full color reproduction capability is lost
Solution Approach 1:
Instead of compressing the color gamut from original to display (forward conversion), the patent inverts the approach by reading the printed image and expanding its color gamut to match the original's maximum color reproduction range. This reverse operation allows the displayed image to achieve full color fidelity while maintaining the ability to represent colors that were originally present in the printed material.
2Loss of information
If the entire reproducible color gamut is discretely expressed in the original, then color information is preserved, but conversion to match display device capabilities requires sophisticated color space transformation
Solution Approach 1:
The patent introduces an intermediary color space transformation process that uses ICC profiles and pseudo-inverse matrices as mediators between the original color space and the display device color space. This intermediary approach systematically maps discrete color gamut points while preserving color information, avoiding direct and complex point-to-point transformations.
Solution Approach 2:
The patent transforms color coordinates by changing the parameter space representation, converting from one color space parameter set to another using mathematical transformations. This allows the discrete color gamut points to be re-expressed in terms of the display device's color parameters while maintaining the integrity of the original color information.
3Productivity
If color coordinates are converted to match display device maximum color reproduction range, then color reproduction effectiveness is improved, but accuracy for various original types must be maintained
Solution Approach 1:
The patent creates a universal color conversion system that can handle various original types (photographs, artwork, printed materials) through a single integrated approach. The system universally applies ICC profile-based transformation and pseudo-inverse matrix calculation to convert any original's color coordinates to the display device's maximum color reproduction range while maintaining accuracy for each specific original type.
Data Source
AI summary
An object of the present invention is to display a color by sufficiently utilizing a color space capable of being displayed by a display. In order to attain the above described object, a color conversion apparatus according to the present invention includes unit that reads an original in which a whole reproducible color gamut is discretely expressed, and acquires color coordinates of a first color space, and color conversion unit that converts the acquired color coordinates of the first color space into a second color space, wherein the color conversion unit converts the color coordinates in the first color space to be substantially the same as color coordinates in the second color space.