source: other-projects/tipple-android/tipple-ar/tipple-standalone-hpg/src/org/greenstone/android/tipple/base/CameraPreview.java@ 26528

package org.greenstone.android.tipple.base;

import android.content.Context;
import android.hardware.Camera;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

    Camera camera;

    public CameraPreview(Context context) {
        super(context);
        getHolder().addCallback(this);
        getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        System.err.println("*** CameraPreview::surfaceCreated()");
        camera = Camera.open();
        try {
            camera.setPreviewDisplay(holder);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        System.err.println("*** CameraPreview::surfaceChanged()");

        Camera.Parameters parameters = camera.getParameters();
        Camera.Size size = getBestPreviewSize(width, height, parameters);

        if (size != null) {
            parameters.setPreviewSize(size.width, size.height);
            camera.setParameters(parameters);
            camera.startPreview();
        } else {
            System.err.println("Could not find a good camera preview size");
        }
    }

    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        System.err.println("*** CameraPreview::surfaceDestroyed()");
        camera.stopPreview();
        camera.release();
        camera = null;
    }

    private Camera.Size getBestPreviewSize(int width, int height, Camera.Parameters parameters) {
        Camera.Size result = null;

        for (Camera.Size size : parameters.getSupportedPreviewSizes()) {
            if (size.width <= width && size.height <= height) {
                if (result == null) {
                    result = size;
                } else {
                    int resultArea = result.width * result.height;
                    int newArea = size.width * size.height;
                    if (newArea > resultArea) {
                        result = size;
                    }
                }
            }
        }

        return (result);
    }
}