Swift Programming

Build OpenCV Contrib as a .xcframework, for iOS, on a M1

We needed an OpenCV Contrib module in an iOS app, using Swift Package Manager. I thought the hardest part would be using OpenCV. How wrong I was.

Photo by Andrea De Santis / Unsplash

Context

We needed an OpenCV Contrib module in an iOS app. When reviewing options, it was decided we would expose a Swift package, wrapping an Objective-C wrapper, that would itself be the one importing OpenCV.

This meant exposing OpenCV as a Swift Package Manager binary target. Which requires us to build a .xcframework.

Goal

Build a .xcframework that we can run on both OS devices and Intel & Apple M1 Mac iPhone / iPad Simulators. Why a .xcframework and not simply a .framework? Because while Swift Package Manager can import binaries, it can only import .xcframework ones, not .framework ones.

Requirements

cmake (installable using brew)
python3 (because python2.7 is obsolete) (installable using brew)
opencv source (via git clone https://github.com/opencv/opencv.git)
opencv_contrib source (via git clone https://github.com/opencv/opencv_contrib.git)

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Context

Goal

Requirements

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