The CImg Library is an open-source C++ toolkit for image processing.
It mainly consists in a (big) single header file CImg.h providing a set of
C++ classes and functions that can be used in your own sources, to load/save,
manage/process and display generic images. It's actually a very simple
toolkit for coding image processing stuffs in C++ : Just include the header
file CImg.h, and you are ready to handle images in your C++ programs.
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documentation. Please refer to http://cimg.eu/reference/index.html or
download a copy from https://github.com/dtschump/CImg