OpenCV is a library of programming functions mainly aimed at real-time computer vision, developed by Intel. It is free for use under the open source BSD license. The library is cross-platform. It focuses mainly on real-time image processing.
This Library majorly used in Image & Video Processing Applications because of its smart performance. Matlab like platforms cannot give you real time performance because of their architectures & has gradually outdated from industry, but OpenCV can give you much more processing power to process your heavy image & video data. Many companies like Google, Intel, IBM, Sony, Honda, Toyota, KPIT Cummins use this library to do many projects. This lightweight library can easily be used on Raspberry Pi for Video Processing application like Face Detection.