精确测量金属镀层工件表面缺陷的图像处理方法

设计了一套自动测量表面缺陷的系统．以面阵CCD采集图像，实现了对金属镀层工件表面图像的双面、高速、高分辨率测量．系统的图像处理采用模块化程序设计，方便实现工件表面精确测量的特定要求．通过两次分别选取闽值，采用经过改进的大津阈值分割法求取特征分割阈值时，能够十分理想地提取工件上的微小缺陷，实现了对金属工件表面的精确测量．该系统针对不同形状、不同镀层的工件表面可以调整LED照明光源的光强，在图像处理中可以调整去光圈和特征检测的灵敏度．通过方便调整系统的技术参数，满足工业现场的具体要求．以钕铁硼小型工件缺陷检测作为应用实例验证了该系统的可行性．

Image Processing of the Precision Measurement on Metal Surface Production Defect

An automatic measurement system for surface defect was designed.The system acquires metal part image by area CCD and realizes two-side,high speed and high resolution measurement.The image processing system introduces moduladzation programme to meet the particular requirement of the surface precision measurement.The threshold modularization introduces a method by choosing the thresholds by two steps.The modified Ostu algorithm threshold method Can inspect inconspicuous defect easily,and realize the precision measurement.For different shapes and different plating coats of the production surface，the system Gan adjust the right intensity of LED hghting lamp-house，the sensitivity coefficient of wiping aperture and the defect detection in image processing.Therefore，it can adjust the technical parameters of the system and meetthe exact requirement of the industry field.Apractical application to the defect inspection of Nd-Fe-B small metal part validates the feasibility of the system.