中文摘要：

数字图像相关法通常用于测量物体的位移和形变,对数字散斑相关法中的二次曲面拟合法、拉格朗日插值法、梯度法3种亚像素算法进行了研究。通过数值模拟实验,对上述亚像素算法进行了综合比较,结果表明,在上述算法中梯度法的精度最高。

英文摘要：

Digital image correlation is usually used for the measurement of displacement and deformation of rigid body.In this paper,three algorithms in digital image correlation including quadratic surface fitting,Lagrange interpolation method and gradient method are studied.Through the numerical simulations,a comprehensive evaluation of three algorithms is made.The results show that the accuracy of the gradient method is the highest.