The Application of Multi-scale Morphological Filter Based on Differential image In Low Intense X-ray Image System

摘要

New structure low intensity x-ray image system is mainly made of plane plate mode x-ray intensifier of single proximity focus and CCD data acquisition and processing system. The paper explains the noise source and characteristic of the low intensity x-ray image system. By the system composition, the image noise source of low x-ray imaging system is constituted with quantum noise, paniculate noise and dark noise of CCD. Then the compound methods of the "multi-frame mean + morphological transform filter" is submitted which deals with the imaging noise. Firstly, some frame images is superimposed, then mean image is calculated from those images, which is under the principle of noise non-correlation. Secondly, distinguishing with the conventional ways of morphological transformation filtering algorithm, the differential image information is referred to de-noising. Under the multi-scale morphological thought, the differential image which is obtained from the source image include s noise and some image details. After the noise of the differential image is cut off by the wavelet translation, the differential image is added to the last filtered image by the multi-scale morphological filter, then the clean image is achieved which has no noise but keeps the image details.