基于分形插值的频域散斑相关法面内位移测量  

In-plane displacement measurement based on frequency domain speckle correlation method with fractal interpolation

作　　者：张红颖[1] 易建军[1] 于之靖[1] 

机构地区：[1]中国民航大学电子信息与自动化学院,天津300300

出　　处：《红外与激光工程》2016年第9期169-174,共6页Infrared and Laser Engineering

基　　金：国家自然科学基金(U1333105);中央高校基本科研业务费(3122015C016)

摘　　要：针对传统频域数字散斑相关法在测量物体面内位移测量精度较低的问题，提出一种基于分形插值的频域数字散斑相关法。该方法在频域数字散斑相关法的基础上，引入Hanning窗函数对图像进行滤波处理，克服了图像边缘效应对最终位移值的影响；同时利用散斑图像的子区域与整幅图像在结构形态和灰度特征的自相似性，采用分形插值的方法进行亚像素插值，进而能精确定位相关点，得到更精确的亚像素位移值。实验结果表明：该方法保持了频域散斑相关法的测量速度，且将测量的绝对误差降低在0.01～0.03 pixel以内，并进一步通过刚体平移实验测试了算法的可靠性。For the low precision of in-plane displacement measurement using traditional digital speckle correlation methodin frequency domain, a new frequency domain correlation method based on fractal interpolation was proposed. Based on traditional digital speckle correlation in frequency domain, this method utilizes Hanning window function to filter the images in order to overcome the influence of edge effect on final displacement values. Considering theself-similarity of the sub-region and the whole imagein structure morphology and gray characteristics, fractal interpolation was adopted to improve the sub-pixel interpolation, which couldlocate relevant pointsand get more accurate sub-pixel displacement values. Experimental results show that this method could reduce the absolute error within 0.01 to 0.03 pixel and maintain the measurement speed as well. Moreover, the reliability of the algorithm is tested through the rigid translation experiments.

关 键 词：面内位移测量 频域 数字散斑相关法 Hanning窗函数 分形插值 

分 类 号：TN247[电子电信—物理电子学]