Image processing on Bitmap

In this exercise, the bitmaps will be processed in form of int[], to swap color.

package com.exercise.AndroidBitmap;

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

public class AndroidBitmapActivity extends Activity {
 
 ImageView image1, image2, image3, image4;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        image1 = (ImageView)findViewById(R.id.image1);
        image2 = (ImageView)findViewById(R.id.image2);
        image3 = (ImageView)findViewById(R.id.image3);
        image4 = (ImageView)findViewById(R.id.image4);
        
        Bitmap bmOriginal = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
        image1.setImageBitmap(bmOriginal);
        
        int width = bmOriginal.getWidth();
        int height = bmOriginal.getHeight();
        int halfWidth = width/2;
        int halfHeight = height/2;
        
        Bitmap bmDulicated2 = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        Bitmap bmDulicated3 = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        Bitmap bmDulicated4 = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        int[] srcPixels = new int[width * height];
        bmOriginal.getPixels(srcPixels, 0, width, 0, 0, width, height);
        int[] destPixels = new int[width * height];
        
        swapGB(srcPixels, destPixels);
        bmDulicated2.setPixels(destPixels, 0, width, 0, 0, width, height);
        image2.setImageBitmap(bmDulicated2);
        
        swapRB(srcPixels, destPixels);
        bmDulicated3.setPixels(destPixels, 0, width, 0, 0, width, height);
        image3.setImageBitmap(bmDulicated3);
        
        swapRG(srcPixels, destPixels);
        bmDulicated4.setPixels(destPixels, 0, width, 0, 0, width, height);
        image4.setImageBitmap(bmDulicated4);

        
    }
    
    void swapGB(int[] src, int[] dest){
     for(int i = 0; i < src.length; i++){
      dest[i] = (src[i] & 0xffff0000)
       | ((src[i] & 0x000000ff)<<8)
       | ((src[i] & 0x0000ff00)>>8);
     }
    }
    
    void swapRB(int[] src, int[] dest){
     for(int i = 0; i < src.length; i++){
      dest[i] = (src[i] & 0xff00ff00)
       | ((src[i] & 0x000000ff)<<16)
       | ((src[i] & 0x00ff0000)>>16);
     }
    }
    
    void swapRG(int[] src, int[] dest){
     for(int i = 0; i < src.length; i++){
      dest[i] = (src[i] & 0xff0000ff)
       | ((src[i] & 0x0000ff00)<<8)
       | ((src[i] & 0x00ff0000)>>8);
     }
    }
}

Related article:
- Bitmap processing: createScaledBitmap, getPixels and setPixels.