OpenCV means Open Source Computer Vision Library. It is a collection of C functions and a few C++ classes that implement many popular Image Processing and Computer Vision algorithms.
The key features:
OpenCV provides cross-platform middle-to-high level API that includes about 300 C functions and a few C++ classes. Also there are constantly improving Python bindings to OpenCV, see interfaces/swig/python and samples/python. OpenCV has no strict dependencies on external libraries, though it can use some (such as libjpeg, ffmpeg, GTK+ etc.) when it is possible.
it can be downloaded from: