实际项目中在用关于图象处理的封装，能实现屏幕截图、获取缩略图并自动计算宽度，按比例缩小图片，剪裁图片，通过图片生成缩略图(非常实用，且有非常详细的注释)-Actual project in the use of image processing in packaging, can realize the screenshot, obtain the thumbnail and automatically calculated width, scale images, image clipping