采用高、低角度光源组合打光方式提取感兴趣区域,构建划痕形态学的中值滤波核以获取准确的背景图像,再经背景差分后提取划痕缺陷。采用基于方向梯度的改进区域生长算法实现了同一划痕的有效连通,降低了划痕缺陷的漏检率。通过对面积、长宽比等主要特征参数的置信度分析,提出了一种多特征加权融合的划痕判定方法。结果表明,利用该方法进行划痕检测的正确率达95.7%,算法处理时间少于1.21 s,达到了工程应用的精度和效率要求。

The region of interest (ROI) is first extracted under the combination lighting mode of high and low angle light sources and then the median filter kernel of scratch morphology is constructed to obtain the accurate background images from ROI. The scratches are extracted after the background difference. An improved region growing algorithm based on directional gradient is adopted to achieve an effective connectivity for the same scratch, which reduces the miss rate of scratch detection. By analyzing the confidence of main scratch detection parameters such as area, length-width ratio and so on, a scratch detection method based on weighted fusion of multi-features is proposed. The results show that, for this method, the accuracy of scratch detection is 95.7%, and the processing time is less than 1.21 s, which meets the accuracy and efficiency requirements for the engineering application.