说明：  （1）利用“文件”菜单中的“打开”、“保存为…”分别实现图片的读取与保存。利用matlab中 “ uigetfile”、“imread” “imshow”实现图像文件的读取与显示：
((1) using the " File" menu in the " Open" , " Save As ..." picture read and save. Use matlab uigetfile " ," imread imshow image file read and display:)