遥感图像的变化检测是对不同时间获取的同一区域 的两个或多个时相的遥感图像地物目标的变化情况进行检测,通过对两时相遥感图像的对比分析，获取该区域特定目标的变化信息。-The analysis of remotely sensed data for object extraction is a key step in an increasing number of GIS(Geographic Information Science) applications, in particular for mapping, updating and change detection purposes.