Lots of great suggestions here. The real prize may be something like getting real-time gpu-accelerated image and video filters on mobile devices. As an alternative to OpenCL / CUDA you can try Vulkan GLSL compute shaders targeting an Android GPU. See NDK docs.
Another possibility arises with active development from the JuliaLang GPU team. As far as I know there is no GPU-accelerated image processing library for the language yet, but all the popular image format encoders exist.
Another possibility arises with active development from the JuliaLang GPU team. As far as I know there is no GPU-accelerated image processing library for the language yet, but all the popular image format encoders exist.
Intro to JuliaGPU Ecosystem
https://www.youtube.com/watch?v=6ntJ_al4oXA
Best of luck ;)