Hi there, I was looking to use OpenCV for IOS in a...

# multiplatform

[Michael Clancy]

Hi there, I was looking to use OpenCV for IOS in a KMM project, though as it is written in C++ this currently seems not possible. I am curious as to whether a wrapper for OpenCV written in objective-c should allow me to do this?

[Big Chungus]

Isn't there an openCV written in C? You could use that to build a KMM native library for ios and android native. Or you could use JNI and android jvm

[Big Chungus]

Wait, what's wrong with their ios and android packs? https://opencv.org/releases/

[Michael Clancy]

Yep there is a C implementation, but it hasnt been maintained in around 10 years I believe, (OpenCV made the switch from C to C++ in 2.4), so functionality like Mat are unavailable.

[Big Chungus]

Ah, fair enough.

[Michael Clancy]

For the packs, I am unsure how I would be able to share my code using these. From what I understand the iOS framework is still written in C++, and so would be accessible from Swift, but not from the kotlin shared code.

[Big Chungus]

Yeah, you'd need multi layer bindings

Cpp to objc to kotlin native

Then with expect actual in common kotlin to kotlin native and android

[Michael Clancy]

This is what im going for currently. I found this: https://github.com/Legoless/LegoCV

It provides bindings for OpenCV in Objective C.
The compilation goes well until cinteropLegoCVIos, for which it fails, can’t currently see what is wrong.

[Michael Clancy]

But mostly just wanted to check that multi layer bindings this should conceptually work, so thank you, I will keep working on it