焊缝X射线探伤数字图象处理方法研究

采用灰度分析法研究了实时X射线探伤图象特征,提出了一种能显著提高图象清晰度和对比度,降低图象噪音的S-T非线性图象变换方法,并用线灰度梯度法成功地提取了焊缝中的缺陷。结果表明:对于噪声成分多、灰度分布范围窄、对比度差的实时X射线探伤图象,S-T变换方法能明显地改善图象质量,线灰度梯度法提取的焊接缺陷定位准确、畸变小。该方法可以在实时X射线探伤系统中应用。

An Application of Digital Image Processing to X-ray Real-time Inspection of Weld Defects

In this paper,the features of the digital image of weld defects which were obtained from X-ray real-time inspection have been investigated by mean of image gray analysis method. A S-T nonlinear image enhancement technique is presented to increase the definition and contrast and to reduce the noises remarkably. By the use of image line-gray gradient,the weld defect has been collected success fully. Experiment results show that digital image of weld defects with high noise, narrow gray lever region,and low contrast can be remarkably improved by use of S-T technique. The weld defects collected by means of line-gray gradient can be exactly positioned with less distortion. This method can be used in real-time X-ray inspection system.