I making an app to detect potholes this the main function camera fragment where I have to use opencv to get the desired result
while using opencv in android java I am facing this issue please help me :
java.lang.NullPointerException: Attempt to invoke virtual method 'void org.opencv.android.BaseLoaderCallback.onManagerConnected(int)' on a null object reference
package com.example.dpgra.defectdetect;
/*import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;*/
//import model.CameraBridgeViewBase;
import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.AssetManager;
import android.location.Location;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.SeekBar;
import android.widget.TextView;
import android.widget.Toast;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.core.Point;
import org.opencv.core.Scalar;
import org.opencv.core.Size;
import org.opencv.imgproc.Imgproc;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import model.Darknet;
import model.Pothole;
import model.PotholeList;
public class CameraFragment extends Fragment implements CameraBridgeViewBase.CvCameraViewListener2, View.OnClickListener, SeekBar.OnSeekBarChangeListener {
private View rootView;
private CameraBridgeViewBase mOpenCvCameraView;
private Darknet net;
private static CameraFragment cameraFragment;
private PotholeList potholeList;
private Integer OrientationIsValid;
private double confidenceThresh;
BaseLoaderCallback mLoaderCallback ;
Mat imageMat;
// JavaCameraView javaCamera2View;
private static String TAG ="CameraFragment";
static
{
if (OpenCVLoader.initDebug())
{
Log.d(TAG,"OpenCV Installed Successfully");
}
else
{
Log.d(TAG,"OpenCV Failed");
}
}
@SuppressLint("ValidFragment")
private CameraFragment() {
super();
potholeList = PotholeList.getInstance();
OrientationIsValid = 0;
confidenceThresh = .6;
}
/**
* Returns the one instance of the camera fragment.
*
* @return the camera fragment
*/
public static CameraFragment getInstance() {
if (cameraFragment == null) {
cameraFragment = new CameraFragment();
}
return cameraFragment;
}
@Override
public void onStart() {
super.onStart();
mOpenCvCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getActivity() != null) {
getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
}
}
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.camera_fragment, container, false);
this.rootView = rootView;
// javaCamera2View= (JavaCameraView) rootView.findViewById(R.id.CameraView);
mOpenCvCameraView = (CameraBridgeViewBase) rootView.findViewById(R.id.CameraView);
//Check if the device is not an emulator
String myDeviceModel = android.os.Build.MODEL;
if (!myDeviceModel.toLowerCase().contains("sdk")) {
//Rotate the camera view 90 degrees clockwise
mOpenCvCameraView.setAngle(90);
// javaCamera2View.setAngle(90);
}
rootView.findViewById(R.id.floatingActionButton2).setOnClickListener(this);
mOpenCvCameraView.setCvCameraViewListener(this);
// javaCamera2View.setCvCameraViewListener(this);
SeekBar seekBar = rootView.findViewById(R.id.seekBar);
seekBar.setOnSeekBarChangeListener(this);
/**
* Makes sure opencv can load successfully.
*/
BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this.getActivity()) {
@SuppressLint("LongLogTag")
@Override
public void onManagerConnected(int status) {
switch (status) {
case BaseLoaderCallback.SUCCESS: {
//Log.i(TAG, "OpenCV loaded successfully");
mOpenCvCameraView.enableView();
// javaCamera2View.enableView();
imageMat = new Mat();
break;
}
default: {
super.onManagerConnected(status);
break;
}
}
}
};
return rootView;
}
/**
* This method is invoked when camera preview has started. After this method is invoked
* the frames will start to be delivered to client via the onCameraFrame() callback.
*
* @param width - the width of the frames that will be delivered
* @param height - the height of the frames that will be delivered
*/
@Override
public void onCameraViewStarted(int width, int height) {
/*
if(OrientationIsValid == 2) {
new AlertDialog.Builder(this.getContext())
.setTitle("Alert")
.setMessage("Do you want to keep this orientation?")
.setPositiveButton("Yes",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
OrientationIsValid = 0;
}
}).setNegativeButton("No", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
OrientationIsValid = 1;
}
}).show();
}
*/
String cfgFile = getPath(".cfg", this.getActivity());
String weightsFile = getPath(".weights", this.getActivity());
if (cfgFile != null && weightsFile != null) {
net = new Darknet(cfgFile, weightsFile);
}
//mOpenCvCameraView.setVisibility(CameraBridgeViewBase.VISIBLE);
}
/**
* This method is invoked when camera preview has been stopped for some reason.
* No frames will be delivered via onCameraFrame() callback after this method is called.
*/
@Override
public void onCameraViewStopped() {
}
/**
* This method is invoked when delivery of the frame needs to be done.
* The returned values - is a modified frame which needs to be displayed on the screen.
* TODO: pass the parameters specifying the format of the frame (BPP, YUV or RGB and etc)
*
* @param inputFrame
*/
@Override
public Mat onCameraFrame(CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
Mat frame = inputFrame.rgba();
Imgproc.cvtColor(frame, frame, Imgproc.COLOR_BGRA2RGB);
Mat mRgbaT = frame;
/* old_mRgbaT = frame.t();
Core.flip(old_mRgbaT, old_mRgbaT, 1);
Imgproc.resize(old_mRgbaT, mRgbaT, frame.size());
old_mRgbaT.release();
*/
Mat temp = null;
for (int i = 0; i < OrientationIsValid; i++) {
temp = frame.t();
Core.flip(temp, temp, 1);
Imgproc.resize(temp, mRgbaT, frame.size());
temp.release();
}
int cols = mRgbaT.cols();
int rows = mRgbaT.rows();
Size cropSize;
if ((float) cols / rows > 1) {
cropSize = new Size(rows * 1, rows);
} else {
cropSize = new Size(cols, cols / 1);
}
int y1 = (int) (rows - cropSize.height) / 2;
int y2 = (int) (y1 + cropSize.height);
int x1 = (int) (cols - cropSize.width) / 2;
int x2 = (int) (x1 + cropSize.width);
Mat subFrame = mRgbaT.submat(y1, y2, x1, x2);
cols = subFrame.cols();
rows = subFrame.rows();
int sevarity = 0;
if (net != null) {
double confidence, xCenter, yCenter, width, height = 0;
Mat retMat = net.forwardLoadedNetwork(mRgbaT);
for (int i = 0; i < retMat.rows(); i++) {
confidence = retMat.get(i, 5)[0];
if (confidence > confidenceThresh) {
printMat(retMat.row(i));
//System.out.println("YESSSSSS");
xCenter = retMat.get(i, 0)[0] * mRgbaT.cols();
yCenter = retMat.get(i, 1)[0] * mRgbaT.rows();
width = retMat.get(i, 2)[0] * mRgbaT.cols();
height = retMat.get(i, 3)[0] * mRgbaT.rows();
Imgproc.rectangle(mRgbaT, new Point((xCenter - width / 2), (yCenter - height / 2)), new Point(xCenter + width / 2
, yCenter + height / 2), new Scalar(255, 0, 0), 4);
Imgproc.putText(mRgbaT, String.format("%.4f", new Double(confidence * 100)) + "%", new Point((xCenter - width / 2), (yCenter - height / 2) - 5)
, 1, 1, new Scalar(255, 0, 0), 2);
sevarity++;
}
}
retMat.release();
subFrame.release();
if (sevarity > 0) {
createPothole(sevarity);
}
} else {
//Log.i("System", "Problem forwarding network");
}
return mRgbaT;
}
private Pothole createPothole(int severity) {
Pothole pothole = null;
if (this.getActivity() != null) {
Location location = ((MainActivity) this.getActivity()).getLocation();
if (location != null) {
pothole = new Pothole(location, createPotholeId(), severity);
addToPotholeList(pothole);
}
}
return pothole;
}
/**
* Creates the id string for a pothole.
*
* @return the pothole id
*/
public String createPotholeId() {
PotholeList list = PotholeList.getInstance();
int num = 0;
if (!list.isEmpty()) {
String lastId = list.get(list.size() - 1).getId();
num = Integer.parseInt(lastId.substring(1));
}
String retId = "p" + (num + 1);
return retId;
}
/**
* Prints the returned matrix outputted from the network.
*
* @param mat the mat to print
*/
private void printMat(Mat mat) {
for (int i = 0; i < mat.rows(); i++) {
//System.out.print("[ ");
for (int n = 0; n < mat.cols(); n++) {
try {
//System.out.printf( "%.2f ", mat.get(i, n)[0]);
} catch (NullPointerException e) {
//System.out.print( " " );
}
}
//System.out.println("]");
}
}
@Override
public void onResume() {
super.onResume();
try {
if (OpenCVLoader.initDebug()) {
Log.d("Debug", "OpenCV library found inside package. Using it!");
mLoaderCallback.onManagerConnected(BaseLoaderCallback .SUCCESS);
}
else {
Log.d("Debug", "Internal OpenCV library not found. Using OpenCV Manager for initialization");
OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_3_0_0, this.getActivity(), mLoaderCallback);
}
}
catch (NullPointerException e) {
Log.d(TAG, String.valueOf(e));
Toast.makeText(this.getActivity(), "OpenCV is required to run this feature. Please install OpenCV from the Google Play Store or download the APK from their official website.", Toast.LENGTH_LONG).show();
}
}
/**
* Gets the path of a file and create it in the app memory.
*
* @param fileType the file to find
* @param context context
* @return the pathname
*/
@SuppressLint("LongLogTag")
private static String getPath(String fileType, Context context) {
AssetManager assetManager = context.getAssets();
String[] pathNames = {};
String fileName = "";
System.out.println("-----------------------------------------------------------------------");
try {
pathNames = assetManager.list("yolo");
} catch (IOException e) {
e.printStackTrace();
}
for (String filePath : pathNames) {
System.out.println(filePath);
if (filePath.endsWith(fileType)) {
fileName = filePath;
break;
}
}
BufferedInputStream inputStream;
try {
// Read data from assets.
inputStream = new BufferedInputStream(assetManager.open(fileName));
byte[] data = new byte[inputStream.available()];
inputStream.read(data);
inputStream.close();
// Create copy file in storage.
File outFile = new File(context.getFilesDir(), fileName);
FileOutputStream os = new FileOutputStream(outFile);
os.write(data);
os.close();
// Return a path to file which may be read in common way.
return outFile.getAbsolutePath();
} catch (IOException ex) {
//Log.i(TAG, "Failed to upload a file");
}
return "";
}
/**
* Adds the pothole to the pothole list.
*
* @param pothole the pothole to add
*/
public boolean addToPotholeList(Pothole pothole) {
return potholeList.add(pothole);
}
@Override
public void onClick(View view) {
OrientationIsValid++;
if (OrientationIsValid > 3) {
OrientationIsValid = 0;
}
}
@Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
confidenceThresh = (double) i / 100;
TextView textView = rootView.findViewById(R.id.confidence);
textView.setText("Confidence Threshold: " + (confidenceThresh * 100) + "%");
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
}
