Copy part of Bitmap

Last post Copy bitmap using getPixels() and setPixels() show how to copy a whole Bitmap using getPixels() and setPixels(). It can be used to copy part of a Bitmap.

package com.AndroidCopyBitmap;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.os.Bundle;
import android.widget.ImageView;

public class AndroidCopyBitmapActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        ImageView image1 = (ImageView)findViewById(R.id.image1);
        ImageView image2 = (ImageView)findViewById(R.id.image2);
        
        Bitmap oldBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
        
        int orgWidth = oldBitmap.getWidth();
        int orgHeight = oldBitmap.getHeight();
        
        int firstx, firsty;
        int halfWidth = orgWidth/2;
        int halfHeight = orgHeight/2;
        
        //Create a same size Bitmap
        Bitmap newBitmap = Bitmap.createBitmap(orgWidth, orgHeight, Bitmap.Config.ARGB_8888);
        //Create a pixel of 1/4 size, to copy part of the bitmap
        int[] pixels = new int[halfWidth * halfHeight];
        
        //Copy Upper-Left part to Bottom-Right
        oldBitmap.getPixels(pixels, 0, halfWidth, 0, 0, halfWidth, halfHeight);
        newBitmap.setPixels(pixels, 0, halfWidth, halfWidth, halfHeight, halfWidth, halfHeight);
         
        //Copy Bottom-Right to Upper-Left part
        oldBitmap.getPixels(pixels, 0, halfWidth, halfWidth, halfHeight, halfWidth, halfHeight);
        newBitmap.setPixels(pixels, 0, halfWidth, 0, 0, halfWidth, halfHeight);
        
        //Copy Bottom-Left part to Upper-Right
        oldBitmap.getPixels(pixels, 0, halfWidth, 0, halfHeight, halfWidth, halfHeight);
        newBitmap.setPixels(pixels, 0, halfWidth, halfWidth, 0, halfWidth, halfHeight);
         
        //Copy Upper-Right to Bottom-Left part
        oldBitmap.getPixels(pixels, 0, halfWidth, halfWidth, 0, halfWidth, halfHeight);
        newBitmap.setPixels(pixels, 0, halfWidth, 0, halfHeight, halfWidth, halfHeight);
         
        image1.setImageBitmap(oldBitmap);
        image2.setImageBitmap(newBitmap);
    }
}