APPLICATION OF NONLINEAR FILTERING TO REDUCING NOISE AND ENHANCING RADIOGRAPHIC IMAGE

Real-time digital radiography is a development tendency for radiographic inspection and diagnosis. Enhancement of image is the key to improve resolution and sensitivity of radiographic inspection. The algorithm and character of rank-order filter which is one of the nonlinear ones are discussed emphatically. All methods have been used to process radiographic image and the results have illustrated that linear filter can reduce noise but corrupt edge, and rank-order filter can reduce noise and preserve the detail at the same time, and is effective on improving image quality.