关键词: X射线图像, 焊缝, 缺陷检测, 反几何扩散, 微弱信号

Abstract: To achieve visual detection of small signal in X-ray defect-image of precision weldment,the segmentation method of weal image information with strong noise and large gray gradient background was studied.An adaptive gradient-threshold method based on the scan line was proposed to quickly identify suspicious defect-region,which significantly reduced the amount of data and the segmentation difficulty.The algorithm to extract small signal in X-ray image of weld defects was developed based on the anti-geometric diffusion model.Through a series of adaptive threshold surfaces-formed by anti-geometric diffusion process,the weal image information of defects was marked and classified,and the noise was identified according to the improved classification rules.The experimental results indicated that the method could accurately extract weal signal in X-ray defect-image with uneven brightness,low contrast and strong noise.The distortion was low and the efficiency was high.

Key words: X-ray image, welding seam, defect detection, anti-geometric diffusion, weal signal