In iOS app development CoreImage is one of the library that provides the facility for image processing and analysis technology designed to provide real time processing for our still images and vedios.
It operates on image data types from the Core Graphics, Core Video and Image frameworks. CoreImage hides the details of low level graphics processing.
CoreImage can analyze the quality of an image and provide a set of filters with optimal setting and can adjust image contrast, tone-color and more.
CoreImage can also detect human face features in still images and also in video images.