Color Conversion Table Creation Using CMYK Scaling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for creating color conversion tables in image forming apparatuses face challenges in achieving high accuracy when the total use amount of color material exceeds a set limit, leading to interpolation errors and prolonged operation times, especially when increasing the number of patch images is not feasible.
Innovation Solution
A method that adjusts input CMYK values for patch images to align with a set amount of color material usage, creating a color conversion table by interpolating between these adjusted values to reduce total color material usage without increasing the number of patch images, thereby minimizing interpolation errors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of patch images is increased to improve color accuracy in low-lightness area, then measurement precision is improved, but loss of time increases due to longer measurement and data processing time
Solution Approach 1:
The patent adjusts the CMYK values of patch images in the low-lightness area by applying a scaling factor to reduce the total use amount of color material. This parameter change allows the system to maintain color accuracy without increasing the number of patch images, thereby avoiding the time loss associated with additional measurements and processing.
2Reliability
If the total use amount of color material is limited to prevent toner fixation failure and ink spreading, then reliability is improved, but manufacturing precision deteriorates due to interpolation errors in color conversion table creation
Solution Approach 1:
The patent performs preliminary adjustment of CMYK values for patch images in the low-lightness area before creating the color conversion table. By pre-scaling the CMYK values to respect the color material limit, the system ensures that the color conversion table is created with accurate data points, preventing interpolation errors while maintaining reliability.
Solution Approach 2:
The patent modifies the CMYK parameter values of patch images by applying a scaling factor to reduce the total use amount of color material. This parameter change ensures that the color conversion table is created using valid data points that respect the color material limitation, thereby maintaining both reliability and manufacturing precision.
3Productivity
If patch images with high total use amount of color material are used to create color conversion table, then productivity is improved by reducing number of patch images, but manufacturing precision deteriorates due to interpolation errors
Solution Approach 1:
The patent applies a scaling factor to the CMYK values of patch images in the low-lightness area to reduce the total use amount of color material. This parameter change allows the system to use fewer patch images while maintaining manufacturing precision, as the scaled values ensure accurate color conversion table creation without interpolation errors.
Data Source
AI summary
Provided is a color conversion table creation method for creating a color conversion table for an image forming apparatus which forms an image by performing, on an input color value with total use amount of color material exceeding set amount, a process for reducing the total use amount of color material, the table presenting correspondence between the input color value input to the image forming apparatus and an output color value in a device-independent color space. The method includes: acquiring an input color value of a patch image for creating the table; when the total use amount of color material defined by the acquired input color value is around the set amount, adjusting the input color value to have a smaller difference between the total use amount and the set amount; and creating the color conversion table using the patch image with the adjusted input color value.