Android Studio Arctic Fox + OpenCv: Using opencv camera in android

MainActivity.java

       

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;

import org.opencv.android.OpenCVLoader;

public class MainActivity extends AppCompatActivity {
    private static String TAG = "MainActivity";
//    static
//    {
//        if(OpenCVLoader.initDebug())
//        {
//            Log.d(TAG, "Opencv installed successfully");
//        }
//        else{
//            Log.d(TAG, "opencv not installed");
//        }
//    }
    private Button open_camera;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        open_camera = findViewById(R.id.open_camera);
        open_camera.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                startActivity(new Intent(MainActivity.this, OpencvCamera.class).addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_CLEAR_TOP));
            }
        });
    }
}

       
 

activity_main.xml

       

           
          <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              xmlns:app="http://schemas.android.com/apk/res-auto"
              xmlns:tools="http://schemas.android.com/tools"
              android:layout_width="match_parent"
              android:layout_height="match_parent"
              tools:context=".MainActivity"
              android:gravity="center|bottom"
              >

              <Button
                  android:layout_width="wrap_content"
                  android:layout_height="50dp"
                  android:id="@+id/open_camera"
                  android:text="Camera"></Button>

          </LinearLayout>

       
 

OpencvCamera.Java

       

package com.example.myapplication;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;

import android.Manifest;
import android.app.Activity;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.util.Log;
import android.view.SurfaceView;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.android.LoaderCallbackInterface;


public class OpencvCamera extends Activity implements CameraBridgeViewBase.CvCameraViewListener2 {
    private static final String TAG = "MainActivity";
    Mat mRGBA;
    Mat mRGBAT;
    CameraBridgeViewBase cameraBridgeViewBase;
    BaseLoaderCallback baseLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(int status) {
            switch (status){
                case LoaderCallbackInterface.SUCCESS:{
                    Log.i(TAG, "onManagerConnected: Opencv loaded");
                    cameraBridgeViewBase.enableView();
                }
                default:{
                    super.onManagerConnected(status);
                }
                break;
            }

        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ActivityCompat.requestPermissions(OpencvCamera.this, new String[]{Manifest.permission.CAMERA},1);
        setContentView(R.layout.activity_opencv_camera);
        cameraBridgeViewBase = (CameraBridgeViewBase) findViewById(R.id.camera_surface);
        cameraBridgeViewBase.setVisibility(SurfaceView.VISIBLE);
        cameraBridgeViewBase.setCvCameraViewListener(this);



    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
//        if request is denied, this will return an empty array
        switch(requestCode){
            case 1:{
                if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                    cameraBridgeViewBase.setCameraPermissionGranted();
                }
                else{
                    //permisiion denied
                }
                return;
            }
        }
    }


    @Override
    protected void onResume() {
        super.onResume();
        if(OpenCVLoader.initDebug()){
//            if load success
            Log.d(TAG, "onResume: Opencv initialized");
            baseLoaderCallback.onManagerConnected(LoaderCallbackInterface.SUCCESS);
        }
        else{
            Log.d(TAG, "onResume: Opencv not initialized");
            OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION, this, baseLoaderCallback);
        }

    }

    @Override
    protected void onPause() {
        super.onPause();
        if(cameraBridgeViewBase !=null){
            cameraBridgeViewBase.disableView();
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        if(cameraBridgeViewBase !=null){
            cameraBridgeViewBase.disableView();
        }
    }

    @Override
    public void onCameraViewStopped() {
        mRGBA.release();

    }

    @Override
    public void onCameraViewStarted(int width, int height) {
        mRGBA = new Mat();
        mRGBAT = new Mat(height, width, CvType.CV_8UC1);

    }

    @Override
    public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
        mRGBA = inputFrame.rgba();
        mRGBAT = inputFrame.gray();
        return mRGBA;
    }
    
}

       
 

activity_opencv_camera.xml

       

           
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <org.opencv.android.JavaCameraView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/camera_surface"/>

</FrameLayout>

       
 

AndroidManifest.xml

       

            
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.myapplication">

    <uses-permission android:name="android.permission.CAMERA"/>
    <uses-feature android:name="android.hardware.camera" android:required="false"/>
    <uses-feature android:name="android.hardware.camera.front" android:required="false"/>
    <uses-feature android:name="android.hardware.camera.autofocus" android:required="false"/>
    <uses-feature android:name="android.hardware.camera.front.autofocus" android:required="false"/>



    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.MyApplication">
        <activity
            android:name=".OpencvCamera"
            android:exported="true" />
        <activity
            android:name=".MainActivity"
            android:exported="true">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            
        
    </application>