Take photo

<uses-permission android:name="android.permission.CAMERA"></uses-permission>  
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<SurfaceView android:id="@+id/surfaceView" android:layout_height="0dip" android:layout_width="0dip"></SurfaceView>
<ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/imageView"></ImageView>
</LinearLayout>

import java.io.IOException;  
  
import android.app.Activity;  
import android.graphics.Bitmap;  
import android.graphics.BitmapFactory;  
import android.hardware.Camera;  
import android.hardware.Camera.Parameters;  
import android.os.Bundle;  
import android.view.SurfaceHolder;  
import android.view.SurfaceView;  
import android.widget.ImageView;  
  
public class TakePicture extends Activity implements SurfaceHolder.Callback  
{  
    //a variable to store a reference to the Image View at the main.xml file  
    private ImageView iv_image;  
    //a variable to store a reference to the Surface View at the main.xml file  
    private SurfaceView sv;  
  
    //a bitmap to display the captured image  
    private Bitmap bmp;  
  
    //Camera variables  
    //a surface holder  
    private SurfaceHolder sHolder;  
    //a variable to control the camera  
    private Camera mCamera;  
    //the camera parameters  
    private Parameters parameters;  
  
    /** Called when the activity is first created. */  
    @Override  
    public void onCreate(Bundle savedInstanceState)  
    {  
        super.onCreate(savedInstanceState);  
        setContentView(R.layout.main);  
  
        //get the Image View at the main.xml file  
        iv_image = (ImageView) findViewById(R.id.imageView);  
  
        //get the Surface View at the main.xml file  
        sv = (SurfaceView) findViewById(R.id.surfaceView);  
  
        //Get a surface  
        sHolder = sv.getHolder();  
  
        //add the callback interface methods defined below as the Surface View callbacks  
        sHolder.addCallback(this);  
  
        //tells Android that this surface will have its data constantly replaced  
        sHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);  
    }  
  
    @Override  
    public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3)  
    {  
         //get camera parameters  
         parameters = mCamera.getParameters();  
  
         //set camera parameters  
         mCamera.setParameters(parameters);  
         mCamera.startPreview();  
  
         //sets what code should be executed after the picture is taken  
         Camera.PictureCallback mCall = new Camera.PictureCallback()  
         {  
             @Override  
             public void onPictureTaken(byte[] data, Camera camera)  
             {  
                 //decode the data obtained by the camera into a Bitmap  
                 bmp = BitmapFactory.decodeByteArray(data, 0, data.length);  
                String filename=Environment.getExternalStorageDirectory()
                                + File.separator + "testimage.jpg";
                FileOutputStream out = null;
                try {
                    out = new FileOutputStream(filename);
                    bmp.compress(Bitmap.CompressFormat.PNG, 100, out); // bmp is your Bitmap instance
                    // PNG is a lossless format, the compression factor (100) is ignored
                } catch (Exception e) {
                    e.printStackTrace();
                } finally {
                    try {
                        if (out != null) {
                            out.close();
                        }
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
                 //set the iv_image  
                 iv_image.setImageBitmap(bmp);  
             }  
         };  
  
         mCamera.takePicture(null, null, mCall);  
    }  
  
    @Override  
    public void surfaceCreated(SurfaceHolder holder)  
    {  
        // The Surface has been created, acquire the camera and tell it where  
        // to draw the preview.  
        mCamera = Camera.open();  
        try {  
           mCamera.setPreviewDisplay(holder);  
  
        } catch (IOException exception) {  
            mCamera.release();  
            mCamera = null;  
        }  
    }  
  
    @Override  
    public void surfaceDestroyed(SurfaceHolder holder)  
    {  
        //stop the preview  
        mCamera.stopPreview();  
        //release the camera  
        mCamera.release();  
        //unbind the camera from this object  
        mCamera = null;  
    }  
}