Raster Image Registration Defect Correction via Color Dilation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional printing techniques face registration defects when printing black objects on colored backgrounds due to mechanical shifts, which are difficult to correct, especially when operating on rasterized images, requiring extensive processing and resource-heavy computations.
Innovation Solution
A method that examines pixels in a neighborhood to determine connected black and color regions, performing a dilation operation to expand color regions adjacent to black objects, thereby reducing registration defects without extensive processing, using a lookup table to address pixel configurations and density criteria.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional processing techniques are used to eliminate registration defects, then registration defects are reduced, but processing time and computational resources increase significantly
Solution Approach 1:
The patent divides the image processing task into two distinct stages: (1) a fast preprocessing stage that operates on the original image to create a simplified representation, and (2) a correction stage that applies registration defect fixes based on the preprocessed data. This segmentation allows the computationally intensive defect correction to be based on simplified data rather than full-resolution images, significantly reducing processing time while maintaining defect reduction effectiveness.
Solution Approach 2:
The patent performs preliminary analysis and extraction of key features from the image before the actual registration defect correction is applied. By pre-identifying potential defect locations, color regions, and registration parameters in advance, the system prepares correction data that can be quickly applied without requiring extensive real-time computation during the actual printing process.
2Reliability
If extensive processing is applied to convert page description format to page images, then registration defects are corrected, but printer speed decreases
Solution Approach 1:
The patent separates the registration correction functionality into a distinct preprocessing module that operates independently from the main page description to page image conversion pipeline. This allows the correction algorithms to work on simplified representations rather than full page images, maintaining printer throughput while improving registration accuracy.
Solution Approach 2:
The patent changes the parameter representation by working with downsampled or thresholded versions of the image data rather than full-resolution multi-bit images. By transforming the image into a simpler parameter space (such as binary masks or reduced-resolution representations), the system can perform registration defect correction with minimal computational overhead, thus maintaining high printer speed.
3Reliability
If complex algorithms are used to identify black objects and color regions in raster images, then registration defects are eliminated, but computational complexity increases
Solution Approach 1:
The patent extracts only the essential information needed for registration defect correction from the full image data. Instead of analyzing complete color images to identify black objects and color regions, the system extracts simplified representations such as binary masks, boundary information, or downsampled versions. This extraction approach maintains defect elimination capability while dramatically reducing the computational complexity of the algorithms required.
Data Source
AI summary
A method and system modify a rasterized digital image to reduce registration artifacts, the image having a black plane and a color plane by determining if a pixel is part of a connected black region and if the pixel is part of a connected color region. It is determined if the pixel is part of a connected black region and a connected color region that are contiguous. A dilation operation is performed on the color plane value of the pixel if the pixel is part of a connected black region and a connected color region that are contiguous.