讲述信号处理中互相关技术的使用原理，并以超声波为例子，来说明其实用性。-About the cross-correlation signal processing techniques in the use of principles, and to ultrasound as an example to illustrate its practicability.

该程序用于计算图像的像素之间的相关性。 relation.m 输出数值结果； relationfigure.m 输出图像结果。(This program is used to calculate the correlation between pixels in image.)