一个c语言写的图像处理库，能够处理PPM, XPM, GIF, PNG ,JPG格式图像-A c language image processing library, able to deal with PPM, XPM, GIF, PNG, JPG format images

vc++实现对ppm格式的图像的旋转，有利于c++的学习和利用c++对图像进行处理的理解-Vc++ realize the format of the image in ppm rotation, is conducive to the study of c++ and the use of c++ image processing understanding