图像预处理

图像的灰度化和二值化
http://blog.sina.com.cn/s/blog_13c6397540102wqtt.html
平滑滤波
https://mp.csdn.net/mdeditor/93305289#
https://www.cnblogs.com/zhuifeng-mayi/p/9558052.html
边缘检测的各种微分算子比较(Sobel,Robert,Prewitt,Laplacian,Canny)
https://www.cnblogs.com/molakejin/p/5683372.html
https://blog.csdn.net/tigerda/article/details/61192943
https://blog.csdn.net/swj110119/article/details/51777422
https://www.cnblogs.com/laumians-notes/p/8310361.html
https://www.cnblogs.com/wxl845235800/p/7700887.html