Printer Lookup Table for Toner Reduction and Hue Preservation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional toner-saving modes in printers fail to maintain image hue due to uniform reduction in CMYK values, leading to inconsistent color differences and suboptimal toner consumption.
Innovation Solution
An image processing apparatus with a lookup table system that derives acceptable color differences for each grid point in the color space, determining new CMYK values to minimize toner consumption while maintaining image hue, by creating an updated lookup table based on acceptable color differences and user settings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If uniform reduction of CMYK values is applied to reduce toner consumption, then toner consumption is reduced, but image hue is not maintained and color difference becomes large
Solution Approach 1:
The patent applies different color difference thresholds to different color regions in the color space. Instead of uniform CMYK reduction, the system divides the color space into multiple regions and assigns appropriate acceptable color difference values to each region, allowing localized optimization of both toner savings and color accuracy.
Solution Approach 2:
The patent dynamically adjusts the acceptable color difference based on the specific color and region in the color space. The color difference threshold is not fixed but varies according to the grid point location and color characteristics, enabling adaptive toner reduction that maintains hue where critical.
2Manufacturing precision
If a fixed color difference threshold is applied to all colors, then color consistency is maintained, but toner consumption cannot be maximally reduced for all colors
Solution Approach 1:
The patent assigns different acceptable color difference thresholds to different color regions and grid points. This allows colors that are less sensitive to changes to have larger thresholds (enabling more toner reduction) while colors that are sensitive maintain smaller thresholds (preserving hue).
Solution Approach 2:
The system changes the acceptable color difference parameter dynamically based on the color and position in the color space. By adjusting this parameter locally rather than globally, the system optimizes the balance between color consistency and toner reduction for each specific color region.
3Loss of substance
If acceptable color difference range is made large, then toner consumption is reduced, but hue cannot be maintained for some colors
Solution Approach 1:
The patent implements location-dependent acceptable color difference thresholds where each grid point in the color space has a customized threshold based on its color characteristics. This ensures that hue maintenance reliability is preserved for colors where it is critical while allowing greater toner reduction for colors where larger deviations are acceptable.
4Reliability
If acceptable color difference range is made small, then hue is maintained, but toner consumption reduction is limited
Solution Approach 1:
The system dynamically changes the acceptable color difference parameter based on the specific color and grid point location. This allows the parameter to be small where hue maintenance is critical and large where toner reduction can be prioritized, optimizing both reliability and substance loss reduction simultaneously.
Data Source
AI summary
An object of the present invention is to provide an image processing apparatus capable of reducing color material consumption to the maximum while maintaining the hue of an image before and after color conversion to reduce the color material consumption. The present invention is an image processing apparatus having a first lookup table to convert pixel values in a color space into pixel values of color materials, the apparatus including: an acceptable color difference derivation unit configured to derive an acceptable color difference indicating a size of a range of acceptable color difference, which corresponds to each grid point in the color space; a pixel value determination unit configured to determine pixel values of color materials, which corresponds to each of the grid points, based on the derived acceptable color difference; and a lookup table creation unit configured to create a second lookup table to convert pixel values in the color space into the determined pixel values of color materials.