GPUImage
iOS framework for GPU-based image and video processing
... manipulation much faster than could be done in CPU-bound routines. It hides the complexity of interacting with the OpenGL ES API in a simplified Objective-C interface. This interface lets you define input sources for images and video, attach filters in a chain, and send the resulting processed image or video to the screen, to a UIImage, or to a movie on disk. Images or frames of video are uploaded from source objects, which are subclasses of GPUImageOutput.