Deblurring Algorithm for Blurred Images Caused by Patient Motion in Radiography
Kohei Ohashi, Takayuki Ishida · Japanese Journal of Radiological Technology · 2016
In radiography, when a blurred image caused by patient motion was acquired, radiologists retake an image as needed. However, retaking an image leads to extra radiation exposure to patients and reducing work efficiency. This study proposes the deblurring algorithm for blurred images caused by patient motion in radiography. In the proposed algorithm, we first take a video using an optical device during radiography. Second, we calculate the optical flow between each frame, and estimate a point spread function (PSF) based on the optical flows. Finally, we restore the blurred image by deconvolution processing. In this study, blurred images with the blur width from 1.0 mm to 5.0 mm at 0.5 mm intervals were obtained by using own moving body phantom, and applied proposed algorithm for each blurred image. To evaluate the algorithm, we measured blur area and structural similarity (SSIM) of the blurred images and deblurred images, and compared the values. As a result, a significant decrease in blur area and a significant increase in SSIM were confirmed in each blur condition. These results suggest the usefulness of the proposed algorithm.