OpenCV on iOS: binary size, load time, speed etc.

Question

I used to use OpenCV a lot, and cross-complied it on an iPhone 4. It was slow. Is it improved now? Any optimization for iOS, like NEON support? How many MB will my final binary increase? And is there any noticeable slowing down in app loading?

I plan to use some algorithms not available in CoreImage and GPUImage.

Answer 1

OpenCV now provides a pre-compiled framework for iOS (updated for iOS 7 and ARM64 recently), so you don't need to cross-compile anymore.

I can't answer you for the binary size increase. For the performance part, OpenCV functions now support GCD multithreading for speed up. I don't think that OpenCV binaries do actually include NEON optimization, but there is a recent book about using OpenCV on iOS that includes a few examples of how to do it yourself.