说明：  提供三种生成缩影图像的方法： 1 、设置缩影文件的宽度，根据设置的宽度和源图像文件的大小来确定新缩影文件的长度来生成缩影图像 2 * 、设置缩影文件的长度，根据设置的长度和源图像文件的大小来确定新缩影文件的宽度来生成缩影图像 3 * 、设置缩影文件相对于源图像文件的比例大小，根据源图像文件的大小及设置的比例来确定新缩影文件的大小来生成缩影图像 * 新生成的缩影图像可以比原图像大，这时即是放大源图像。
(Provide three methods of generating image epitome: 1, set the width of the miniature file, according to the set width and the source image file to determine the size of the length of the file to generate a new miniature miniature image 2 *, set the epitome of the length of the file, according to the length and the source image file to determine the size of the new miniature file width to generate a miniature image 3 *, setting a miniature file relative to the source image file size, depending on the size and set the source image file to determine the proportion of the size of the file to generate a new miniature miniature image * new miniature image can be generated than the original image, then the image source is put.)