CNN Image Stitching for Small-Overlap X-Ray Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image stitching methods in X-ray imaging face challenges with inaccurate stitching results and failures due to local maxima or minima in similarity measures, leading to increased patient dose and unreliable stitching processes, especially for large or elongated anatomical structures.
Innovation Solution
A convolutional neural network (CNN) is trained to determine optimal displacement for image stitching by optimizing its parameters and penalizing deviations from a reference cost function, allowing seamless image combination with reduced overlapping areas and patient dose.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If large overlapping areas are used in image stitching, then the stitching reliability is improved, but the patient dose increases
Solution Approach 1:
The patent applies preliminary action by training a convolutional neural network in advance to recognize and predict displacement patterns in overlapping image areas. The pre-trained CNN model can accurately determine the correct displacement between adjacent X-ray images even with minimal overlap, eliminating the need for large overlapping areas that would otherwise be required to ensure stitching reliability. This preliminary training enables the system to achieve reliable stitching results with reduced patient dose.
2Object-affected harmful factors
If small overlapping areas are used in image stitching, then the patient dose is reduced, but the stitching reliability deteriorates
Solution Approach 1:
The patent applies parameter changes by transforming the traditional approach of relying on large overlapping areas into a parameter-based solution using a trained CNN model. The system changes from using spatial overlap extent as the key parameter for reliability to using learned displacement parameters from the neural network. This parameter transformation allows accurate displacement determination even with minimal overlapping areas, maintaining stitching reliability while reducing patient dose.
3Device complexity
If similarity measures are used for displacement estimation, then the stitching process is simplified, but the accuracy deteriorates due to local maxima or minima
Solution Approach 1:
The patent applies mechanics substitution by replacing the traditional mechanical/optical similarity measure approach with a neural network-based system. Instead of using mathematical similarity computations that are prone to local maxima and minima, the system uses a CNN model that has learned displacement patterns from training data. This substitution maintains computational efficiency while dramatically improving displacement estimation accuracy by avoiding the local extrema problems inherent in similarity-based methods.
Data Source
Figure 1~2
Figure 3
AI summary
The invention concerns an image processing system configured for carrying out a computer-implemented method for generating a stitched image with a convolutional neural network (208), a computer-implemented method for generating a stitched image with a convolutional neural network, and a method of training a convolutional neural network, for determining an image representation for image stitching. The training of the convolutional neural network comprises receiving image data, wherein the image data comprises at least two images (101, 102), overlapping each other in an overlapping area (103, 203) in which the images overlapping each other in a target anatomy (104), and wherein the overlapping area comprises an optimum displacement between the two images such that the two images can be correctly combined for image stitching, determining a cost function (105, 205) of the displacement of the two images in the overlapping area, determining a deviation of the cost function from a reference cost function, and optimizing the CNN based on the deviation.