Radiation Image Dark Component Correction via Segmented Evaluation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing radiation imaging apparatuses face challenges in correcting varying dark components caused by image lag during dark correction processing, leading to potential overcorrection and loss of object information.
Innovation Solution
An image processing technique involving a first correction unit for subtracting a first dark image from an object image, an evaluation value obtaining unit for assessing a varying dark component using a second dark image, and a second correction unit for removing the varying dark component based on the evaluation value, effectively addressing the image lag issue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If dark correction processing is performed using the average value of dark images obtained at predetermined intervals, then fixed pattern noise is corrected, but image lag affects the correction result causing overcorrection and loss of object information
Solution Approach 1:
The patent segments the correction process into two distinct stages: first correction using dark images obtained at predetermined intervals to remove fixed pattern noise, and second correction using dark images obtained immediately before object image capturing to remove varying dark components. This segmentation allows each correction stage to target specific noise types without interfering with each other, thereby preventing overcorrection and preservation of object information.
Solution Approach 2:
The patent performs preliminary action by obtaining a dark image immediately before capturing the object image, and uses this dark image to correct varying dark components in the object image. This timing ensures that the dark image reflects the actual state of the detection unit just before object detection, eliminating image lag effects and preventing overcorrection while maintaining accurate object information.
2Productivity
If dark images are obtained at predetermined intervals, then correction processing can be performed, but varying dark components caused by image lag cannot be accurately corrected
Solution Approach 1:
The patent divides correction processing into two segmented operations: first correction handling fixed pattern noise using periodically obtained dark images (maintaining productivity), and second correction handling varying dark components using dark images obtained immediately before object imaging (ensuring precision). This segmentation allows the system to maintain efficient periodic correction while adding precise point-in-time correction without significant overhead.
Solution Approach 2:
The patent introduces an intermediary correction step that uses dark images obtained immediately before object image capturing. This intermediary correction acts as a mediator between the periodic first correction and the final object image, specifically targeting varying dark components that the first correction cannot address, thereby improving overall correction accuracy without compromising the efficiency of the primary correction process.
3Measurement precision
If overcorrection occurs due to image lag, then fixed pattern noise is reduced, but object information is lost
Solution Approach 1:
The patent segments the correction process to apply different correction strategies to different noise components. The first correction removes fixed pattern noise using periodically obtained dark images, while the second correction removes varying dark components using dark images obtained immediately before object imaging. This segmentation prevents overcorrection by ensuring that each correction stage targets only its specific noise type, thereby preserving object information while maintaining reliable correction of fixed pattern noise.
Solution Approach 2:
The patent implements feedback by obtaining dark images immediately before object image capturing and using them to correct varying dark components in the object image. This feedback mechanism ensures that the correction process adapts to the actual state of the detection unit at the moment of object imaging, preventing overcorrection and preserving object information while maintaining reliable fixed pattern noise removal.
Data Source
AI summary
An image processing apparatus includes: a first correction unit configured to perform correction processing of subtracting a first dark image obtained in a state without radiation irradiation from an object image, thereby removing a dark component of the object image; an evaluation value obtaining unit configured to obtain an evaluation value by a varying dark component included in a corrected image that has undergone the correction processing based on the first dark image and a second dark image obtained after the first dark image; and a second correction unit configured to perform correction processing of removing the varying dark component from the corrected image based on the evaluation value.