说明：  视频尺寸变化源代码，它用于将大尺寸图片转换成小尺寸，也可以将小尺寸转换成大尺寸，同时在屏幕上显示出转化后的视频图像
(Video size change the source code, which is used to large-size picture converted into a small size, small size can also be converted at National Cheng Kung University size, at the same time on the screen showing the video image after conversion)