This sounds really cool, but I'm not 100% sure what it means. Is this something that would be included in desktop software for rendering images on the screen, or something more useful for file conversion and running operations on images to produce new image files?
I think it's important to read this article (http://www.sunsetlakesoftware.com/2012/02/12/introducing-gpu...) before fully diving into this project. GPUImage (the first version) at a high level gave everyone the ability to create the Instagram effect (realtime video capture and image processing) with little to no effort. Now you will not find "Instagram" in that blog post but I've messed around with almost all of the sample projects in the original codebase and it's hard not to try and create some similar effects, plus I think it's an easy use case to explain to others. With that said, this project goes so far and above Instagram (honestly they shouldn't be compared, but again, easy way to explain it quickly), the use cases are really just limited to what you can think of regarding image processing and rendering.
You missed the point. Try applying those effects in realtime, on an iPhone 4s, to a live video stream coming directly from the camera. It's quite difficult, even with everything that CoreImage provides. GPUImage? It's cake.
Not sure about the 4s specifically, but there are all kinds of apps that do it on the iPhone using the GPU (so, if GPUImage works on 4s, they should too). In fact Apple also provides a built-in one...
"The objective of the framework is to make it as easy as possible to set up and perform realtime video processing or machine vision against image or video sources. By relying on the GPU to run these operations, performance improvements of 100X or more over CPU-bound code can be realized. This is particularly noticeable in mobile or embedded devices. On an iPhone 4S, this framework can easily process 1080p video at over 60 FPS. On a Raspberry Pi 3, it can perform Sobel edge detection on live 720p video at over 20 FPS."
