在实际应用或科研领域，很多时候要对图像裁剪操作。图像裁剪就是在源图像或者大图像中裁剪图像块来，这个图像块一般是多边形的。图像裁剪是图像处理中最基本的操作之一。-In the actual application or scientific research field, and many times to image cutting operation. The image is the source image or cut in large image cut image block, the image block is generally the polygon. Image cut is the most basic image processing of one of the operation.