机械密封微小形变图像测量系统像素当量的标定

在机械密封数字散斑微小形变图像测量系统中,像素当量的标定工作介于图像采集和处理之间；基于VC++2008 MFC开发了图像像素当量标定系统；系统包含了抓图、图像的阈值分割、形态学处理、扫描检测标定块的边缘及线性回归分析功能；介绍了抓图软件的开发过程；编制了形态学的腐蚀、膨胀及开/闭运算的函数,使用这些函数实现了图像的形态学处理；在形态学处理后显示图像的基础上框选包含标定块的理想区域使用扫描法获取边缘信息；对获取的边缘信息进行线性回归分析拟合出标定块的上下边缘的直线方程,根据拟合出的方程求出两条直线间的距离,最后用标定块的实际宽度除以直线间的距离即为像素当量；运行结果表明获得了亚像素级别的像素当量,保证了后期使用DSCM方法计算微小形变的精度.

Pixel Equivalent Demarcating For Minute Image Deform Measuring System of Mechanical Seal

In the system for minute digital speckle deform measuring system of mechanical seal,pixel equivalent demarcating is between image capturing and image processing.Pixel equivalent demarcating system of image is developed on the basis of VC++2008 MFC.The system’s function includes image snap,threshold segmentation,morphological image processing,edge scan detection of demarcating block and linear regression analysis.The developing process of image snap software is introduced.morphological eroding,dilation,opening and closing function are compiled;and morphological image processing is realized by using these functions.On the morphological processed image,box select the ideal area which includes the demarcating block;obtain edge information by using scan method.Process the edge information with linear regression analysis,fit the straight-line of top edge and bottom edge of the demarcating block;calculate the distance of the fitted equation.Finally pixel equivalent equals the real width of the demarcating block divide the distance of fitted straight-lines.The operational result shows that sub-pixel level pixel equivalent is obtained.It ensure necessary accuracy when calculate the minute with DSCM method.