get color by touch camera live

Question

I did create camera live now I want now the value of color (r, g, b) after get the touched pixel (x, y) I have my attempt but it show always R(0)G(0)B(0) I want know what is the problem... that is my code I used java in android studio and open CV

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

import android.Manifest;
import android.annotation.SuppressLint;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import org.opencv.android.CameraActivity;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Mat;
import java.util.Collections;
import java.util.List;

public class MainActivity extends CameraActivity {

    CameraBridgeViewBase cameraBridgeViewBase;
    TextView textView2, textView1;
    Bitmap bitmap;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        getPermission();

        cameraBridgeViewBase = findViewById(R.id.cameraView);
        textView2 = findViewById(R.id.textView2);
        textView1 = findViewById(R.id.textView);


        cameraBridgeViewBase.setCvCameraViewListener(new CameraBridgeViewBase.CvCameraViewListener2() {
            @Override
            public void onCameraViewStarted(int width, int height) {

            }

            @Override
            public void onCameraViewStopped() {}

            @Override
            public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
                return inputFrame.rgba();
            }
        });
        if(OpenCVLoader.initDebug()){
            cameraBridgeViewBase.enableView();
        }
        cameraBridgeViewBase.setDrawingCacheEnabled(true);
         cameraBridgeViewBase.buildDrawingCache(true);
        cameraBridgeViewBase.setOnTouchListener(new View.OnTouchListener() {
            
            @SuppressLint({"SetTextI18n", "ClickableViewAccessibility"})
            @Override
            public boolean onTouch(View view, MotionEvent motionEvent) {
                bitmap = cameraBridgeViewBase.getDrawingCache();

                int h =bitmap.getHeight();
                int x = (int) motionEvent.getX();
                int y = (int) motionEvent.getY();
               

                int pixel = bitmap.getPixel(x, y);
                int r = Color.red(pixel);
                int g = Color.green(pixel);
                int b = Color.blue(pixel);



                textView2.setText("R("+r+")"+"G("+g+")"+"B("+b+")");
                textView2.setTextColor(Color.WHITE);
                textView2.setBackgroundColor(Color.rgb(r,g,b));


                return true;
            }
        });
    }

    @Override
    protected void onResume() {
        super.onResume();
        cameraBridgeViewBase.enableView();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        cameraBridgeViewBase.disableView();
    }

    @Override
    protected void onPause() {
        super.onPause();
        cameraBridgeViewBase.disableView();
    }

    @Override
    protected List<? extends CameraBridgeViewBase> getCameraViewList() {
        return Collections.singletonList(cameraBridgeViewBase);
    }

    void getPermission(){
        if(checkSelfPermission(Manifest.permission.CAMERA)!=PackageManager.PERMISSION_GRANTED){
            requestPermissions(new String[]{Manifest.permission.CAMERA},101);
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (grantResults.length > 0 && grantResults[0] != PackageManager.PERMISSION_GRANTED) {
            getPermission();
        }
    }
}

want know the value (r,g,b) of color after touch pixel