Variable GCR Profiles for Spot Color Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for deriving spot color recipes in N-color printing are computationally intensive and often result in non-smooth rendering due to differences in halftone structures and ink cost inefficiencies, particularly when using max-GCR strategies, which can lead to high mottle and graininess.
Innovation Solution
A novel system and method that uses pre-computed GCR strategies in printer profiles to optimize CMYK values for attributes like graininess, mottle, color stability, and ink cost, allowing for interpolation between profiles to determine optimal recipes with reduced computational effort, and iteratively refines these recipes for improved accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of substance
If max-GCR strategy is used to minimize ink cost, then ink cost is reduced, but mottle and graininess increase significantly
Solution Approach 1:
The patent changes the GCR parameter from fixed max-GCR to variable GCR levels (0-100%), allowing optimization of the trade-off between ink cost and image quality. The system computes histograms of CMYK values across the image and uses these to determine optimal GCR levels for different regions, thereby reducing both ink cost and visual defects simultaneously
Solution Approach 2:
The patent introduces dynamic GCR adjustment where the GCR level is not fixed but varies across different image regions based on local characteristics. The system dynamically computes optimal GCR values for different areas using histogram analysis and quality metrics, allowing the recipe to adapt to local image content rather than applying a uniform max-GCR strategy throughout
2Object-affected harmful factors
If min-GCR strategy is used to reduce mottle and graininess, then image smoothness is improved, but ink cost increases
Solution Approach 1:
The patent changes the GCR parameter from fixed min-GCR to variable GCR levels (0-100%), allowing optimization of the trade-off between image smoothness and ink cost. The system computes histograms of CMYK values across the image and uses these to determine optimal GCR levels for different regions, thereby reducing both ink cost and visual defects simultaneously
Solution Approach 2:
The patent introduces dynamic GCR adjustment where the GCR level is not fixed but varies across different image regions based on local characteristics. The system dynamically computes optimal GCR values for different areas using histogram analysis and quality metrics, allowing the recipe to adapt to local image content rather than applying a uniform min-GCR strategy throughout
3Manufacturing precision
If computational optimization of all CMYK recipes is performed to find optimal spot color recipes, then color accuracy and smoothness are improved, but computational time and resources increase significantly
Solution Approach 1:
The patent performs preliminary computation of CMYK histograms and quality metrics before final recipe determination. By pre-computing these intermediate results and storing them for later use in optimization, the system avoids redundant calculations and significantly reduces the computational time required for spot color emulation while maintaining accuracy
Solution Approach 2:
The patent extracts and utilizes only the essential components (histogram data and quality metrics) needed for optimization, rather than computing all possible CMYK recipes exhaustively. This selective extraction of critical information enables efficient optimization with reduced computational burden while still achieving accurate and smooth spot color rendering
Data Source
AI summary
What is disclosed is a novel system and method for obtaining optimum CMYK values for spot colors, with significantly lower computational effort, by using a set of printer profiles with different pre-computed GCR strategies. Various versions are discussed on how to utilize and/or choose among these profiles for each spot color. The present invention is applicable to spot color emulation for CMYK as well as N-color printing, and can be used to optimize one or more image quality attributes, including graininess, mottle, color stability, ink cost, etc. Various embodiments are disclosed.