Dynamic Tone Value Selection for Density Nonuniformity Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for reducing density nonuniformity in inkjet printing and electrophotographic image forming require increasing the number of test charts to achieve accurate density correction, leading to inefficiencies in processing and resource usage.
Innovation Solution
An image processing apparatus that generates a chart image with dynamically selected tone values based on measurement data, omitting patches outside a predetermined condition range, allowing for accurate density nonuniformity correction while reducing the number of patches needed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the number of test charts is increased to achieve accurate density correction, then measurement precision is improved, but productivity deteriorates due to increased processing time and resource usage
Solution Approach 1:
The patent extracts and removes unnecessary patches from test charts by identifying and eliminating tone values that do not contribute to accurate density correction. This is achieved by analyzing the relationship between tone values and density values, then selectively removing redundant patches while preserving only those essential for correction accuracy, thereby reducing the number of test charts needed.
Solution Approach 2:
Instead of using all possible tone values in test charts, the patent applies partial action by selecting only the necessary subset of tone values required for accurate density correction. This selective approach avoids the excessive use of resources while maintaining correction precision, generating test charts with optimized, minimal patch sets.
2Measurement precision
If the number of patches in test charts is increased to reduce tone intervals, then measurement precision is improved, but device complexity increases due to more patches to manage
Solution Approach 1:
The patent removes unnecessary patches from test charts by identifying tone values that are redundant for density correction. By extracting only the essential patches needed for accurate measurement and correction, the system reduces test chart complexity while preserving measurement precision through selective retention of critical tone value patches.
Solution Approach 2:
The patent changes the parameter of test chart composition by dynamically adjusting which tone values are included based on their contribution to density correction accuracy. This parameter optimization allows the system to maintain fine tone measurement capability with fewer patches, reducing complexity while preserving precision.
3Measurement precision
If the number of test charts is increased to achieve fine tone measurement, then measurement precision is improved, but loss of time increases due to more charts to process
Solution Approach 1:
The patent extracts and removes unnecessary test charts from the processing sequence by identifying which tone values are essential for fine tone measurement and density correction. By eliminating redundant charts and keeping only the necessary subset, the system achieves fine tone measurement accuracy with reduced processing time.
Solution Approach 2:
The patent applies partial action by processing only the essential subset of test charts required for fine tone measurement rather than all possible charts. This selective processing approach maintains measurement precision while significantly reducing the time loss associated with processing excessive numbers of test charts.
Data Source
AI summary
An image processing apparatus includes a generation unit generating a first chart image having a plurality of patches with different tone values, an obtaining unit obtaining measurement values acquired by measuring a test chart created by forming the first chart image on a medium, the measurement values indicating densities of a color material in regions of the test chart corresponding to the respective patches, and a selection unit selecting at least one tone value in a range in which an output characteristic of the image forming apparatus derived based on the tone values of the respective patches and the measurement values satisfies a predetermined condition. The generation unit generates a second chart image having a patch corresponding to the selected tone value included and at least one patch corresponding to the tone value outside the range in which the output characteristic satisfies the predetermined condition is omitted among the patches.