运动物体检测 opencv源码下载

【实例简介】通过opencv 库识别摄像头中运动物体

此实例需要安装opencvmanger的库apk，不安装的话自己编译opencv

【实例截图】

【核心代码】

import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SurfaceView;
import android.view.WindowManager;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.Toast;

import org.opencv.android.BaseLoaderCallback;
import org.opencv.android.CameraBridgeViewBase;
import org.opencv.android.CameraBridgeViewBase.CvCameraViewFrame;
import org.opencv.android.CameraBridgeViewBase.CvCameraViewListener2;
import org.opencv.android.LoaderCallbackInterface;
import org.opencv.android.OpenCVLoader;
import org.opencv.core.Mat;
import org.opencv.core.MatOfPoint;
import org.opencv.core.Scalar;
import org.opencv.imgproc.Imgproc;
import org.opencv.video.BackgroundSubtractorMOG;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends Activity implements CvCameraViewListener2, OnSeekBarChangeListener
{
    private static final String TAG = "OCVSample::Activity";

    private CameraBridgeViewBase mOpenCvCameraView;
    private boolean              mIsJavaCamera = true;
    private MenuItem             mItemSwitchCamera = null;

    private BackgroundSubtractorMOG sub;
    private Mat mGray;
    private Mat mRgb;
    private Mat mFGMask;
    private List<MatOfPoint> contours;
    private double lRate = 0.5;

    private SeekBar sb;

    // Initialization required by apps using OpenCV Manager
    private BaseLoaderCallback mLoaderCallback = new BaseLoaderCallback(this)
    {
        @Override
        public void onManagerConnected(int status)
        {
            switch (status) {
                case LoaderCallbackInterface.SUCCESS:
                {
                    Log.i(TAG, "OpenCV loaded successfully");
                    mOpenCvCameraView.enableView();
                } break;
                default:
                {
                    super.onManagerConnected(status);
                } break;
            }
        }
    };

    public MainActivity() {
        //Log.i(TAG, "Instantiated new " this.getClass());
    }

    /** Called when the activity is first created. */
    public void onCreate(Bundle savedInstanceState) {
        Log.i(TAG, "called onCreate");
        super.onCreate(savedInstanceState);
        getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);

        setContentView(R.layout.activity_main);

        //sets up camera
        if (mIsJavaCamera)
            mOpenCvCameraView = (CameraBridgeViewBase) findViewById(R.id.tutorial1_activity_java_surface_view);
        else
            mOpenCvCameraView = (CameraBridgeViewBase) findViewById(R.id.tutorial1_activity_native_surface_view);

        mOpenCvCameraView.setVisibility(SurfaceView.VISIBLE);

        mOpenCvCameraView.setCvCameraViewListener(this);

        //sets up seek bar to adjust learning rate
        sb = (SeekBar)findViewById(R.id.seekBar1);
        sb.setProgress(5);
        sb.setMax(10);
        sb.setOnSeekBarChangeListener(this);
    }

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

    public void onResume()
    {
        super.onResume();
        OpenCVLoader.initAsync(OpenCVLoader.OPENCV_VERSION_2_4_9, this, mLoaderCallback);
    }

    public void onDestroy() {
        super.onDestroy();
        if (mOpenCvCameraView != null)
            mOpenCvCameraView.disableView();
    }

    public boolean onCreateOptionsMenu(Menu menu) {
        Log.i(TAG, "called onCreateOptionsMenu");
        mItemSwitchCamera = menu.add("Toggle Native/Java camera");
        return true;
    }

    //Switching between native and Java libraries for controlling cameras, may not be working fully!
    public boolean onOptionsItemSelected(MenuItem item) {
        String toastMesage = new String();
        Log.i(TAG, "called onOptionsItemSelected; selected item: " item);

        if (item == mItemSwitchCamera) {
            mOpenCvCameraView.setVisibility(SurfaceView.GONE);
            mIsJavaCamera = !mIsJavaCamera;

            if (mIsJavaCamera) {
                mOpenCvCameraView = (CameraBridgeViewBase) findViewById(R.id.tutorial1_activity_java_surface_view);
                toastMesage = "Java Camera";
            } else {
                mOpenCvCameraView = (CameraBridgeViewBase) findViewById(R.id.tutorial1_activity_native_surface_view);
                toastMesage = "Native Camera";
            }

            mOpenCvCameraView.setVisibility(SurfaceView.VISIBLE);
            mOpenCvCameraView.setCvCameraViewListener(this);
            mOpenCvCameraView.enableView();
            Toast toast = Toast.makeText(this, toastMesage, Toast.LENGTH_LONG);
            toast.show();
        }

        return true;
    }

    public void onCameraViewStarted(int width, int height)
    {
        //creates a new BackgroundSubtractorMOG class with the arguments
        sub = new BackgroundSubtractorMOG(3, 4, 0.8, 0.5);

        //creates matrices to hold the different frames
        mRgb = new Mat();
        mFGMask = new Mat();
        mGray = new Mat();

        //arraylist to hold individual contours
        contours = new ArrayList<MatOfPoint>();

    }

    public void onCameraViewStopped() {
    }

    public Mat onCameraFrame(CvCameraViewFrame inputFrame)
    {
        contours.clear();
        //gray frame because it requires less resource to process
        mGray = inputFrame.gray();

        //this function converts the gray frame into the correct RGB format for the BackgroundSubtractorMOG apply function
        Imgproc.cvtColor(mGray, mRgb, Imgproc.COLOR_GRAY2RGB);

        //apply detects objects moving and produces a foreground mask
        //the lRate updates dynamically dependent upon seekbar changes
        sub.apply(mRgb, mFGMask, lRate);

        //erode and dilate are used  to remove noise from the foreground mask
        Imgproc.erode(mFGMask, mFGMask, new Mat());
        Imgproc.dilate(mFGMask, mFGMask, new Mat());

        //drawing contours around the objects by first called findContours and then calling drawContours
        //RETR_EXTERNAL retrieves only external contours
        //CHAIN_APPROX_NONE detects all pixels for each contour
        Imgproc.findContours(mFGMask, contours, new Mat(), Imgproc.RETR_EXTERNAL , Imgproc.CHAIN_APPROX_NONE);

        //draws all the contours in red with thickness of 2
        Imgproc.drawContours(mRgb, contours, -1, new Scalar(255, 0, 0), 2);
        //TODO 判断contours 的size 有无，来决定是否有运动物体经过
        Log.d("NICK", "-----------contours:" contours.size()); // 大于10 的情况下算有物体经过
        return mRgb;
    }

    @Override
    public void onProgressChanged(SeekBar arg0, int arg1, boolean arg2)
    {
        lRate = (double) arg1 / 10.0;
    }

    @Override
    public void onStartTrackingTouch(SeekBar arg0)
    {
        // TODO Auto-generated method stub

    }

    @Override
    public void onStopTrackingTouch(SeekBar arg0)
    {
        // TODO Auto-generated method stub

    }
}