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FAQ

How do I add OpenCV to my Android app?

One Gradle line with the official package:

implementation("org.opencv:opencv:5.0.0.1")

Then initialise before use:

if (!OpenCVLoader.initLocal()) {
    Log.e("OpenCV", "initialisation failed")
}

No NDK, no manual .so copying — the AAR bundles the native libs.

Why is org.opencv.ml / SVM missing in 5.0?

Classic ML moved from core to opencv_contrib in OpenCV 5.0, and the official AAR ships core only. Same story for Haar cascades / HOG (xobjdetect) and G-API (gapi). See the Migration Guide. To get them back without rebuilding the SDK, use OpenCV Pro.

Why don't my Haar cascades work anymore after upgrading?

Because the Haar/HOG detection code moved to the xobjdetect contrib module in 5.0. It's not in the official AAR. Either stay on 4.x, rebuild with contrib, or use OpenCV Pro.

Can I get face recognition with the official AAR?

Face detection yes (DNN / objdetect). Face recognition (LBPHFaceRecognizer, FaceRecognizerSF) is in the face contrib module — not in the official AAR. See examples/face-recognition-contrib.

Do I need to rebuild OpenCV to get contrib modules?

Normally yes — and it's the #1 pain point devs report (CMake errors, broken NDK toolchains, ABI mismatches, days lost). OpenCV Pro is a prebuilt AAR with core + all contrib, so you skip the rebuild entirely.

Which ABIs does OpenCV Pro support?

arm64-v8a and x86_64 (covers modern devices + emulators). API 24+, 16 KB page aligned (Android 15 ready).

Is this the official OpenCV?

No. The official AAR is org.opencv:opencv on Maven Central — use it for the core modules (we link to it and provide examples). OpenCV Pro by Jokobee is a separate, prebuilt core + contrib AAR for the modules the official package doesn't ship.

Contact

Jokobee · https://www.jokobee.com · contact@jokobee.com