A Method of Radiographic Image Quality Enhancement

The quality of the image is one of the important influential factors in the process of defect evaluation of weld radiographic image. To improve the brightness and contrast of digital image of weld radiographic film, a new quality enhancement method in accordance with human visual system is proposed. The human visual resolution ability of the gray and the imaging model of digital system are introduced, then the gray-level mapping transformation function is given in this paper. The processed method is compared with the images enhanced by histogram equalization, linear strength and logarithmic transformation. An experimental case study is provided to illustrate our work, the results demonstrated that the proposed method can improve Peak Signal to Noise Ratio, structure similarity and correlation coefficient by 17.6 times, 1.8 times and 0.2 times, reduce mean absolute error and mean square error by 75% and 94%.