Image Edge Sharpness Correction via Zoom Ratio Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional image processing methods struggle to enhance edge sharpness effectively, especially in images with small signal level changes and suffer from excessive overshoot and undershoot after image enlargement, leading to inadequate edge crispness.
Innovation Solution
An image processing apparatus and method that involves edge width correction through detection and interpolation, followed by enlargement and further edge enhancement, using zoom ratio control values to adjust edge widths before and after enlargement, and calculating enhancement values based on high-frequency components to improve edge sharpness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If edge enhancement is performed after image enlargement using conventional methods, then image sharpness can be improved, but overshoot and undershoot widths become excessively large reducing edge crispness
Solution Approach 1:
The patent applies edge width correction before image enlargement to prevent excessive overshoot and undershoot. By correcting edge widths in advance using zoom ratio control values calculated from edge width information, the subsequent edge enhancement produces narrower overshoot/undershoot regions, thereby improving both edge sharpness and maintaining edge crispness.
Solution Approach 2:
The patent changes the processing sequence and parameters by performing edge width correction before enlargement rather than after. It calculates zoom ratio control values based on detected edge width information and applies these to the interpolation filter, transforming how edge parameters are handled throughout the processing chain to achieve superior edge quality.
2Measurement precision
If conventional edge enhancement based on high frequency components is applied, then edges with large signal level changes are improved, but edges with small signal level changes remain uncorrected
Solution Approach 1:
The patent applies different processing strategies to different edge types. It detects edge width information and calculates different zoom ratio control values based on local edge characteristics. This allows edges with small signal level changes to receive appropriate correction through the edge width correction process, while high contrast edges benefit from both edge width correction and subsequent edge enhancement.
Solution Approach 2:
The patent segments the edge processing into distinct stages: edge width correction based on detected edge width information, followed by edge enhancement based on high frequency components. This segmentation allows different processing methods to target different edge characteristics, improving overall adaptability across various edge types in the image.
Data Source
AI summary
A first edge width correction process (2) is carried out in which edge widths are corrected by an interpolation process using zoom ratio control values (RZC) generated according to the edge widths in image data; an enlargement processing process (3) that enlarges the image data with edge widths corrected by the first edge width correction process (2) is carried out; a second edge width correction process (4) similar to the first edge width correction process is carried out on the enlarged image data; and an edge enhancement process that enhances edges in the image data with edge widths corrected by the second edge width correction process is carried out. An image processing apparatus is obtained that mitigates the loss of sharpness in an enlarged image and accordingly makes it possible to provide better picture quality.