This paper presents an image processing method for the synthesis of images derived by scanning a metallic object using a meander-type eddy-current testing (ECT) probe. In spite of many advantages; this probe cannot detect, the defects extending in the scanning direction, and we need to examine the sample twice to detect all the defects, and naturally we get two images to be analyzed. The proposed method unifies those images keeping information on defects such as amplitude, taking summation of two images avoiding the duplicated utilization of the defect-data commonly contained in two images. The discrete Fourier transform (DFT) is utilized for the elimination of defects in the undesired directions, considering the fact that the required pass band shape of filters for the classification of the defect-orientation is very simple. The effectiveness of the method is demonstrated through an example of aluminum plate and the problem to be improved is simultaneously discussed.
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