基于小波系数差值法的变化信息自动发现

本文将二维小波变换应用于土地利用遥感动态监测，以自动探测土地利用变化信息。在对两时相多光谱影像主成分变换的基础上，选择前面三个主分量进行小波变换，对两时相对应主分量的小波系数求差，土地利用未发生变化区域的差值接近0，而发生变化区域的差值绝对值较大，能量高，因此，经小波逆变换得到的影像能够高亮度地显示出土地利用发生变化的区域。利用遥感数据进行仿真和野外验证发现。该方法得到的监测结果精度能满足实际应用的需要。

Detecting Change Information Automatically by Method of Wavelet Coefficient Difference

Tow dimensional wavelet transform is widely used in various fields of image processing.It is utilized in landuse remote sensing dynamic monitoring to detect chang information automatically in the paper. By using PCA transform on the multi spectrum images of two different periods, the first three principal components were chosen to perform wavelet transform, and the two temporal wavelet coefficients of corresponding principal components were subtracted. It is detected that value difference of land using areas with no change was approximately zero, while the absolute value difference of the changing areas was great and with high energy, so the image performed wavelet counter transform can display land using changing areas with high brightness. Using image data to emulate and field validate the monitor result, the precision using the method mentioned here can meet the demand of practical application.