OPENCV学习笔记2-5_扫描图像并访问相邻像素

　　To illustrate this recipe, we will apply a processing function that sharpens an image（锐化图像的处理函数）. This time, the processing cannot be accomplished in-place. Users need to provide an output image. The image scanning(扫描)is done using three pointers, one for the current line, one for the line above, and another one for the line below.　　To illustrate this recipe, we will apply a pr