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I am making an application where the camera takes a video and shows the average RGB value per frame. I am able to get the RGB value of each frame with good accuracy. I am also able to see the FPS with enableFpsMeter(). The problem is that i want to plot a graph of the R value against time for which i need to store the FPS in a variable. I have been trying to figure that out for a few days now. I know that OpenCV for android does not have any inbuilt methods in its library which will allow me to do that. I have tried the following ways, 1. Tried to create own methods in the JavaCameraView class. 2. Tried making a class which extends JavaCameraView and define a method to find the FPS. Both of which i failed.

What i want is to control the FPS. i want to set the FPS within a range of 8-16. and also plot a graph of the R value against time or FPS (i guess once i get the fps i cant change it easily to time domain).

My Class

package com.example.virus.bloodpressurereader;
import android.hardware.Camera;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.util.Log; 
import android.view.SurfaceView;
import android.view.View;

import com.jjoe64.graphview.GraphView;
import com.jjoe64.graphview.Viewport;
import com.jjoe64.graphview.series.DataPoint;
import com.jjoe64.graphview.series.LineGraphSeries;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.JavaCameraView;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.core.Scalar;
import org.opencv.imgproc.Imgproc;

import static org.opencv.core.Core.getTickCount;
import static org.opencv.core.Core.getTickFrequency;
import static org.opencv.core.Core.inRange;


public class VideoRecordingActivity extends AppCompatActivity implements CameraBridgeViewBase.CvCameraViewListener2{

 //custom toolbar
private Toolbar toolbar;

//java camera view
JavaCameraView javaCameraView;

Mat mRgba, mHsv;

GraphView graph;
LineGraphSeries<DataPoint> series;

CustomizableCameraView customizableCameraView;

//callback loader
BaseLoaderCallback mCallBackLoader = new BaseLoaderCallback(this) {
    @Override
    public void onManagerConnected(int status) {
        switch (status){
            case BaseLoaderCallback.SUCCESS:
                javaCameraView.enableView();
                break;
            default:
                super.onManagerConnected(status);
                break;
        }
    }
};


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

    //custom toolbar
    toolbar = (Toolbar)findViewById(R.id.nav_action);
    setSupportActionBar(toolbar);

    //connect the camera
    javaCameraView = (JavaCameraView)findViewById(R.id.java_camera_view);

    //set visibility
    javaCameraView.setVisibility(View.VISIBLE);
    javaCameraView.setMaxFrameSize(320, 240);



    javaCameraView.enableFpsMeter();
    javaCameraView.clearFocus();

    //set callback function
    javaCameraView.setCvCameraViewListener(this);

    /*Graph*/
    graph = (GraphView)findViewById(R.id.graphView);
    Viewport graphView = graph.getViewport();
    graphView.setScrollable(true);



}

@Override
protected void onPause() {
    super.onPause();
    //if java camera view not = null
    if(javaCameraView!=null){
        javaCameraView.disableView();
    }
}

@Override
protected void onDestroy() {
    super.onDestroy();
    //check if java camera view not = null
    if (javaCameraView!=null){
        javaCameraView.disableView();
    }
}

@Override
protected void onResume() {
    super.onResume();

    if (OpenCVLoader.initDebug()){
        Log.d("openCV", "Connected");

        //display when the activity resumed,, callback loader
        mCallBackLoader.onManagerConnected(LoaderCallbackInterface.SUCCESS);


    }else{
        Log.d("openCV", "Not connected");
        OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_3_3_0, this, mCallBackLoader);
    }
}

@Override
public void onCameraViewStarted(int width, int height) {
    //4 channel
    mRgba = new Mat(width, height, CvType.CV_8UC4);
    mHsv = new Mat(width, height, CvType.CV_8UC3);

}

@Override
public void onCameraViewStopped() {
    //release
    mRgba.release();
}

@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
    //get each frame from camera
    mRgba = inputFrame.rgba();


    /**********HSV conversion**************/
    //convert mat rgb to mat hsv
    Imgproc.cvtColor(mRgba, mHsv, Imgproc.COLOR_RGB2HSV);

    //find scalar sum of hsv
    Scalar mColorHsv = Core.sumElems(mHsv);

    int pointCount = 320*240;


    //convert each pixel
    for (int i = 0; i < mColorHsv.val.length; i++) {
        mColorHsv.val[i] /= pointCount;
    }

    //convert hsv scalar to rgb scalar
    Scalar mColorRgb = convertScalarHsv2Rgba(mColorHsv);

    /*Log.d("intensity", "Color: #" + String.format("%02X", (int)mColorHsv.val[0])
            + String.format("%02X", (int)mColorHsv.val[1])
            + String.format("%02X", (int)mColorHsv.val[2]) );*/
    //print scalar value
    //Log.d("intensity", "R:"+ String.valueOf(mColorRgb.val[0])+" G:"+String.valueOf(mColorRgb.val[1])+" B:"+String.valueOf(mColorRgb.val[2]));

    /*Convert to YUV*/

    final int R = (int) mColorRgb.val[0];
    int G = (int) mColorRgb.val[1];
    int B = (int) mColorRgb.val[2];

    int Y = (int) (R *  .299000 + G *  .587000 + B *  .114000);
    int U = (int) (R * -.168736 + G * -.331264 + B *  .500000 + 128);
    int V = (int) (R *  .500000 + G * -.418688 + B * -.081312 + 128);

    //int I = (R+G+B)/3;


    //Log.d("intensity", "I: "+String.valueOf(I));
    Log.d("intensity", "Y:"+ String.valueOf(Y)+" U:"+String.valueOf(U)+" V:"+String.valueOf(V));



    /*Graph*/
    double t = (double)getTickCount();
    t = ((double) getTickCount() - t)/getTickCount()/getTickFrequency();

    Log.d("tick count", String.valueOf(t));


    return mRgba;

}



//convert Mat hsv to scalar
private Scalar convertScalarHsv2Rgba(Scalar hsvColor) {
    Mat pointMatRgba = new Mat();
    Mat pointMatHsv = new Mat(1, 1, CvType.CV_8UC3, hsvColor);
    Imgproc.cvtColor(pointMatHsv, pointMatRgba, Imgproc.COLOR_HSV2RGB);

    return new Scalar(pointMatRgba.get(0, 0));
}
}

My class which extends the JavaCameraView class is

package com.example.virus.bloodpressurereader;

import android.content.Context;
import android.hardware.Camera;
import android.util.AttributeSet;
import org.opencv.android.JavaCameraView;

/**
 * Created by virus on 9/22/2017.
 */

public class CustomizableCameraView extends JavaCameraView {

Context mContext;
int minFps, maxFps;
public CustomizableCameraView(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public void setPreviewFPS(double min, double max){
    Camera.Parameters params = mCamera.getParameters();
    params.setPreviewFpsRange((int)(min*1000), (int)(max*1000));
    mCamera.setParameters(params);
}
}

When i try to call the extended class into my main class, i get errors because the extended class constructor takes the Context and AttributeSet. but i am passing 2 double value. Can anyone please help me with this?