Image Matching Aperture Problem Detection via Gradient Direction Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image matching methods face errors due to aperture problems, particularly when standard images have one-dimensional features or mixed textures with high and low contrast, leading to incorrect determination of aperture problem regions and subsequent parallax calculation errors.
Innovation Solution
An image processing device that generates reliability by calculating pixel value changes in multiple directions for each local region, correcting gradient directions, and evaluating the uniformity of gradient directions to accurately determine aperture problem regions and improve matching reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If two-dimensional searching is performed to reduce parallax calculation errors, then matching accuracy is improved, but computational complexity increases
Solution Approach 1:
The patent segments the standard image into multiple local regions and performs gradient direction calculations independently for each region. This segmentation allows the system to identify aperture problem regions more efficiently by analyzing local gradient uniformity, reducing the overall computational burden compared to exhaustive two-dimensional searching while maintaining accuracy.
Solution Approach 2:
The patent performs preliminary gradient direction calculations and variance analysis on the standard image before conducting the full block matching process. By pre-identifying regions with uniform gradient directions (aperture problem regions), the system can anticipate and handle potential matching errors in advance, reducing the need for complex corrective searching.
2Difficulty of detecting and measuring
If gradient direction variance is used to determine aperture problem regions, then detection capability is improved, but reliability decreases for linear textures and mixed contrast images
Solution Approach 1:
The patent applies local quality analysis by calculating gradient directions and variances for each local region independently rather than for the entire standard image. This localized approach allows the system to accurately identify aperture problem regions even in images with linear textures or mixed contrast, as each region is evaluated based on its own gradient characteristics without being influenced by other regions.
Solution Approach 2:
The patent introduces a new dimension of analysis by calculating gradient directions in multiple directions (not just single-direction gradients) and evaluating the uniformity of these gradient directions across local regions. This multi-dimensional gradient analysis provides more robust detection of aperture problem regions, improving reliability for challenging image types like linear textures and mixed contrast images.
Data Source
Figure 1A~1C
Figure 2
Figure 3
AI summary
An image processing device that generates reliability of matching between a first image and a second image includes a pixel value change generation unit configured to set a standard image including a pixel of interest in the first image or the second image to generate at least a first pixel value change in a first direction and a second pixel value change in a second direction for each local region of the standard image, a gradient direction generation unit configured to generate a gradient direction of the local region based on the first pixel value change and the second pixel value change, a gradient direction correction unit configured to correct the gradient direction in accordance with the gradient direction, and a reliability generation unit configured to generate the reliability based on the gradient direction corrected by the gradient direction correction unit.