Untitled

import java.io.IOException;
import java.util.List;

import android.content.Context;
import android.hardware.Camera;
import android.hardware.Camera.Size;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;

public class OverlayView extends SurfaceView implements Callback {

        SurfaceHolder mHolder;
        Camera mCamera;

        public OverlayView(Context context) {
                super(context);

                // Install a SurfaceHolder.Callback so we get notified when the
                // underlying surface is created and destroyed.
                mHolder = getHolder();
                mHolder.addCallback(this);
                mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

        }

        public void surfaceCreated(SurfaceHolder holder) {
                // The Surface has been created, acquire the camera and tell it where
                // to draw.
                mCamera = Camera.open();
                mCamera.setDisplayOrientation(90);
                try {
                        mCamera.setPreviewDisplay(holder);
                } catch (IOException e) {
                        mCamera.release();
                        mCamera = null;
                }
        }

        public void surfaceDestroyed(SurfaceHolder holder) {
                // Surface will be destroyed when we return, so stop the preview.
                // Because the CameraDevice object is not a shared resource, it's very
                // important to release it when the activity is paused.
                mCamera.stopPreview();
                mCamera.release();
                mCamera = null;
        }

        private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
        final double ASPECT_TOLERANCE = 0.1;
        double targetRatio = (double) w / h;
        if (sizes == null) return null;

        Size optimalSize = null;
        double minDiff = Double.MAX_VALUE;

        int targetHeight = h;

        // Try to find an size match aspect ratio and size
        for (Size size : sizes) {
            double ratio = (double) size.width / size.height;
            if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
            if (Math.abs(size.height - targetHeight) < minDiff) {
                optimalSize = size;
                minDiff = Math.abs(size.height - targetHeight);
            }
        }

        // Cannot find the one match the aspect ratio, ignore the requirement
        if (optimalSize == null) {
            minDiff = Double.MAX_VALUE;
            for (Size size : sizes) {
                if (Math.abs(size.height - targetHeight) < minDiff) {
                    optimalSize = size;
                    minDiff = Math.abs(size.height - targetHeight);
                }
            }
        }
        return optimalSize;
    }

        public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
                // Now that the size is known, set up the camera parameters and begin
                // the preview.
                Camera.Parameters parameters = mCamera.getParameters();

        List<Size> sizes = parameters.getSupportedPreviewSizes();
                Size optimalSize = getOptimalPreviewSize(sizes, w, h);
                Log.d("DEBUG", optimalSize.width + "," + optimalSize.height);
                parameters.setPreviewSize(optimalSize.width, optimalSize.height);

                mCamera.setParameters(parameters);
                mCamera.startPreview();

        }
}