There are a lot of developers (or would-be developers) interested in finding a foothold in the world of Apple Metal, but are stymied from the start by lack of adequate documentation and simple examples. While Apple's claim that MetalKit was built just for those developers, it has failed to provide sample code comprehensible to the newbie. A dark room, as it appears in the Camera app for iPhone The same room, after applying the histogram equalization Metal Performance Shader This post should remedy that by showing beginners how to use MetalKit to display video frames from the camera on iPhone using Metal, both with Metal Performance Shaders (pre-packaged code) and Metal Shaders (hand-coded). The first app uses the histogram equalization Metal Performance Shader; the second app uses a Metal pass-through shader only. A steep learning curve for all image-processing frameworks—vImage, OpenGL, etc—is what is extending the development time for Chroma (an app I
My inevitable demise, daily.