import java.io.IOException;
import org.opencv.android.Utils;
import org.opencv.core.Core;
import org.opencv.core.CvType;
import org.opencv.core.Mat;
import org.opencv.imgproc.Imgproc;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.hardware.Camera;
import android.hardware.Camera.PreviewCallback;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class CameraViewAndroid extends SurfaceView implements SurfaceHolder.Callback, Runnable {
	private static final String TAG = "Sample::SurfaceView";

	private Camera              mCamera;
	private SurfaceHolder       mHolder;
	private byte[]              mFrame;
	private Mat mYuv;
	private Mat mRgba;

	public CameraViewAndroid(Context context) {
		super(context);
		mHolder = getHolder();
		mHolder.addCallback(this);
		Log.i(TAG, "Instantiated new " + this.getClass());
	}

	public void surfaceChanged(SurfaceHolder _holder, int format, int width, int height) {
		Log.i(TAG, "surfaceCreated");
		if (mCamera != null) {
			Camera.Parameters params = mCamera.getParameters();
			params.setPreviewSize(640,480);
			mCamera.setParameters(params);
			try {
				mCamera.setPreviewDisplay(null);
			} catch (IOException e) {
				Log.e(TAG, "mCamera.setPreviewDisplay fails: " + e);
			}
			mCamera.startPreview();
		}
	}

	public void surfaceCreated(SurfaceHolder holder) {
		Log.i(TAG, "surfaceCreated");

		mYuv = new Mat(480 + 480 / 2, 640, CvType.CV_8UC1);
		mRgba = new Mat();

		mCamera = Camera.open();
		mCamera.setPreviewCallback(new PreviewCallback() {
			public void onPreviewFrame(byte[] data, Camera camera) {
				synchronized (CameraViewAndroid.this) {
					mFrame = data;
					CameraViewAndroid.this.notify();
				}
			}
		});
		(new Thread(this)).start();
	}

	public void surfaceDestroyed(SurfaceHolder holder) {
		Log.i(TAG, "surfaceDestroyed");
		if (mCamera != null) {
			synchronized (this) {
				mCamera.stopPreview();
				mCamera.setPreviewCallback(null);
				mCamera.release();
				mCamera = null;
			}
		}
	}

	public double timet(double l){
		return ((Core.getTickCount() - l)/Core.getTickFrequency()) * 1000;
	}

	public void run() {
		int i = 0 ;
		double d, total = 0;
			
		while (true) {
			d = Core.getTickCount();
			Bitmap bmp = null;

			synchronized (this) {
				try {
					this.wait();

					mYuv.put(0, 0, mFrame);
					Imgproc.cvtColor(mYuv, mRgba, Imgproc.COLOR_YUV420sp2RGB, 4);
					bmp = Bitmap.createBitmap(640,480, Bitmap.Config.ARGB_8888);
					Utils.matToBitmap(mRgba, bmp);                   

				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}

			if (bmp != null) {
				Canvas canvas = mHolder.lockCanvas();
				if (canvas != null) {
					canvas.drawBitmap(bmp, (canvas.getWidth() - bmp.getWidth()) / 2, (canvas.getHeight() - bmp.getHeight()) / 2, null);
					mHolder.unlockCanvasAndPost(canvas);
				}
				bmp.recycle();
			}
			total += timet(d);
			if((i++ % 100) == 0){
				Log.w("Android Camera", "Average frame time: " + total/100 + "ms" + " ##Frame Rate:" + (100000/(total)) + "fps");
				total = 0;
			}
		}
	}
}