Android Camera In OpenCv

For using camera in OpenCv. CameraBridgeViewBase is class provide surfaceView for android camera .

code of CameraActivity class

package com.techamongus.opencvcamera;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.ContentValues;
import android.content.Intent;
import android.hardware.Camera;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.v7.app.ActionBarActivity;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SubMenu;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Toast;

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.Mat;
import org.opencv.imgcodecs.Imgcodecs;
import org.opencv.imgproc.Imgproc;

import java.io.File;
import java.util.List;

public class CameraActivity extends Activity implements CameraBridgeViewBase.CvCameraViewListener2 {

    // A tag for log output.
    private static final String TAG =
            CameraActivity.class.getSimpleName();
    // A key for storing the index of the active camera.
    private static final String STATE_CAMERA_INDEX = "cameraIndex";
    // A key for storing the index of the active image size.
    private static final String STATE_IMAGE_SIZE_INDEX =
            "imageSizeIndex";
    // An ID for items in the image size submenu.
    private static final int MENU_GROUP_ID_SIZE = 2;
    // The index of the active camera.
    private int mCameraIndex;
    // The index of the active image size.
    private int mImageSizeIndex;
    // Whether the active camera is front-facing.
    // If so, the camera view should be mirrored.
    private boolean mIsCameraFrontFacing;
    // The number of cameras on the device.
    private int mNumCameras;
    // The camera view.
    private CameraBridgeViewBase mCameraView;
    // The image sizes supported by the active camera.
    private List<Camera.Size> mSupportedImageSizes;
    // Whether the next camera frame should be saved as a photo.
    private boolean mIsPhotoPending;
    // A matrix that is used when saving photos.
    private Mat mBgr;
    // Whether an asynchronous menu action is in progress.
    // If so, menu interaction should be disabled.
    private boolean mIsMenuLocked;
    // The OpenCV loader callback.
    private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this) {
        @Override
        public void onManagerConnected(final int status) {
            switch (status) {
                case LoaderCallbackInterface.SUCCESS:
                    Log.d(TAG, "OpenCV loaded successfully");
                    mCameraView.enableView();
                    mBgr = new Mat();
                    break;
                default:
                    super.onManagerConnected(status);
                    break;
            }
        }

    };
    @SuppressLint("NewApi")
    @Override
    protected void onCreate(final Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        final Window window = getWindow();
        window.addFlags(
                WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
        if (savedInstanceState != null) {
            mCameraIndex = savedInstanceState.getInt(
                    STATE_CAMERA_INDEX, 0);
            mImageSizeIndex = savedInstanceState.getInt(
                    STATE_IMAGE_SIZE_INDEX, 0);
        } else {
            mCameraIndex = 0;
            mImageSizeIndex = 0;
        }
        final Camera camera;
        if (Build.VERSION.SDK_INT >=
                Build.VERSION_CODES.GINGERBREAD) {
            Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
            Camera.getCameraInfo(mCameraIndex, cameraInfo);
            mIsCameraFrontFacing =
                    (cameraInfo.facing ==
                            Camera.CameraInfo.CAMERA_FACING_FRONT);
            mNumCameras = Camera.getNumberOfCameras();
            camera = Camera.open(mCameraIndex);
        } else { // pre-Gingerbread
            // Assume there is only 1 camera and it is rear-facing.
            mIsCameraFrontFacing = false;
            mNumCameras = 1;
            camera = Camera.open();
        }
        final Camera.Parameters parameters = camera.getParameters();
        camera.release();
        mSupportedImageSizes =
                parameters.getSupportedPreviewSizes();
        final Camera.Size size = mSupportedImageSizes.get(mImageSizeIndex);
        mCameraView = new JavaCameraView(this, mCameraIndex);
        mCameraView.setMaxFrameSize(size.width, size.height);
        mCameraView.setCvCameraViewListener(this);
        setContentView(mCameraView);
    }
    public void onSaveInstanceState(Bundle savedInstanceState) {
        // Save the current camera index.
        savedInstanceState.putInt(STATE_CAMERA_INDEX, mCameraIndex);
        // Save the current image size index.
        savedInstanceState.putInt(STATE_IMAGE_SIZE_INDEX,
                mImageSizeIndex);
        super.onSaveInstanceState(savedInstanceState);
    }
    @SuppressLint("NewApi")
    @Override
    public void recreate() {
        if (Build.VERSION.SDK_INT >=
                Build.VERSION_CODES.HONEYCOMB) {
            super.recreate();
        } else {
            finish();
            startActivity(getIntent());
        }
    }
    @Override
    public void onPause() {
        if (mCameraView != null) {
            mCameraView.disableView();
        }
        super.onPause();
    }
    @Override
    public void onResume() {
        super.onResume();
        OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_3_2_0,
                this, mLoaderCallback);
        mIsMenuLocked = false;
    }
    @Override
    public void onDestroy() {
        if (mCameraView != null) {
            mCameraView.disableView();
        }
        super.onDestroy();
    }
     public Mat onCameraFrame(final CameraBridgeViewBase.CvCameraViewFrame inputFrame) {
        final Mat rgba = inputFrame.rgba();
        if (mIsPhotoPending) {
            mIsPhotoPending = false;
            //takePhoto(rgba);
        }
        if (mIsCameraFrontFacing) {
            // Mirror (horizontally flip) the preview.
            Core.flip(rgba, rgba, 1);
        }
        return rgba;
    }