opencv-android

Project that bundles the OpenCV for Android to be used via Gradle without the need to download the OpenCV Manager app on user's device.

Usage

Add the code below in your root build.gradle file:

allProjects {
    repositories {
        maven { url "https://jitpack.io" }
    }
}

And in your build.gradle (app module) add the implementation command:

dependencies {
    implementation 'com.github.ramonrabello:opencv-android:{latest version}'
}

Please check the library latest release that can be used.

Shrinking the release APK size

You will notice that, after the opencv-android lib had been downloaded, the final size of your project will increase drastically, up to 73 MB. This happen because it was embedded with all OpenCV .so files for each ABI architecture (x86, mips, armeabi, ...), as you can see in the image below after using the APK Analyzer.

A solution for that is to split APKs for each ABI architecture. For this, just add the splits directive inside your build.gradle of app module:

splits {
    abi {
        enable true
        reset()
        include 'x86', 'x86_64', 'armeabi', 'armeabi-v7a', 'mips', 'mips64', 'arm64-v8a'
        universalApk false
    }
}

This will instruct Gradle to build multiple APKs. So, after split process, you can notice that the APK size shrunk up to 8 MB as shown in the image below.

Initializing OpenCV

Call OpenCVLoader.initDebug() to initialize OpenCV engine. A best practice is to call it inside your Application, like the code below (in Kotlin):

class MyApplication : Application() {
    override fun onCreate(){
        super.onCreate()
        OpenCVLoader.initDebug(){
            // put your initialization logic here
        }
    }
}

Do not forget to add the bind the <application> android:name attribute with your Application class. Finally, sync your project and wait to complete the build. If all went successfully, now you can begin to use all available OpenCV module classes like Imgproc, Mat, ...

Disclaimer

This project was developed entirely by my own according to previous experience in creating CV-based apps. I'm not directly involved in OpenCV development and maintenance.

License