How to run OpenCV code without OpenCv Manager

Question

I am using OpenCV4Android version 2.4.10 and i test my code on Samsung Galayx GT-I9300. the problem i have is, that i must download Opencv Manager from play store so that my

Answer 1

Share to you about my way.

1. Download opencv sdk for android at: https://opencv.org/releases.html
2. Unzip opencv sdk
3. In your project (ex ADVisionProject), open settings.gradle file and add config below

--

def opencvsdk = ''
include ':opencv'
project(':opencv').projectDir = new File(opencvsdk + '/sdk')

Example with my settings.gradle file

include ':app'

def opencvsdk = '/Volumes/Data/Projects/machine-learning/OpenCV-android-sdk'
include ':opencv'
project(':opencv').projectDir = new File(opencvsdk + '/sdk')

4. In app/build.gradle, add opencv module to dependencies

--

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
   ....
    implementation project(':opencv')

}

5. Write some codes for testing. About below code, it read drawable image to Mat and convert color to gray mode, convert Mat to Bitmap and display Bitmap into ImageView.

--

import android.graphics.Bitmap;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ImageView;

import org.opencv.android.OpenCVLoader;
import org.opencv.android.Utils;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.core.Size;
import org.opencv.imgproc.Imgproc;

import java.io.IOException;

public class MainActivity extends AppCompatActivity {

    static {
        OpenCVLoader.initDebug();
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ImageView imageView = findViewById(R.id.activity_main_iv_result);
        try {
            Mat img = Utils.loadResource(this, R.drawable.eye);
            Mat gryimg =  new Mat(img.size(),CvType.CV_8U);
            Imgproc.cvtColor(img, gryimg, Imgproc.COLOR_RGB2GRAY);
            Bitmap bm = Bitmap.createBitmap(gryimg.cols(), gryimg.rows(), Bitmap.Config.ARGB_8888);
            Utils.matToBitmap(gryimg, bm);
            imageView.setImageBitmap(bm);
        } catch (IOException e) {
            e.printStackTrace();
        }


    }
}

6. Try to build apk and install to android device. It’s not require OpenCV manager. But I realize the apk size quite big, about 80MB initial

Tested with opencv-3.4.1-android-sdk and Android Studio 3.1.3

We have some way to integrate sdk to your project. You should read /sdk/build.gradle for getting more options