Adjust brightness of a bitmap

To adjust brightness of a bitmap, simple change value of individual color components.

Example:

package com.AndroidBitmapProcessing;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Paint;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.SeekBar;
import android.widget.SeekBar.OnSeekBarChangeListener;
import android.widget.TextView;

public class AndroidBitmapProcessingActivity extends Activity {
 
 ImageView imageView_Source, imageAfter;
 Bitmap bitmap_Source, bitmap_Dest;
 
 SeekBar brightnessBar;
 TextView brightnessText;
 Button doProcess;
 
 int brightnessValue = 0;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        imageView_Source = (ImageView)findViewById(R.id.source);
        imageAfter = (ImageView)findViewById(R.id.imageAfter);

        bitmap_Source = BitmapFactory.decodeResource(getResources(), R.drawable.testpicture);
        imageAfter.setImageBitmap(processingBitmap_Brightness(bitmap_Source));
        
        brightnessBar = (SeekBar)findViewById(R.id.brightnessBar);
        brightnessText = (TextView)findViewById(R.id.brightnessText);
        doProcess = (Button)findViewById(R.id.doProcess);
        
        brightnessBar.setOnSeekBarChangeListener(brightnessBarChangeListener);
        doProcess.setOnClickListener(doProcessClickListener);
        
    }
    
    OnClickListener doProcessClickListener
    = new OnClickListener(){

  @Override
  public void onClick(View v) {
   // TODO Auto-generated method stub
   imageAfter.setImageBitmap(processingBitmap_Brightness(bitmap_Source));
  }};
    
    OnSeekBarChangeListener brightnessBarChangeListener
    = new OnSeekBarChangeListener(){

  @Override
  public void onProgressChanged(SeekBar seekBar, int progress,
    boolean fromUser) {
   brightnessValue = progress - 255;
   brightnessText.setText(String.valueOf(brightnessValue));
  }

  @Override
  public void onStartTrackingTouch(SeekBar seekBar) {
   // TODO Auto-generated method stub
   
  }

  @Override
  public void onStopTrackingTouch(SeekBar seekBar) {
   // TODO Auto-generated method stub
   
  }
     
    };
    
    private Bitmap processingBitmap_Brightness(Bitmap src){
     Bitmap dest = Bitmap.createBitmap(
       src.getWidth(), src.getHeight(), src.getConfig());
         
     for(int x = 0; x < src.getWidth(); x++){
      for(int y = 0; y < src.getHeight(); y++){
       int pixelColor = src.getPixel(x, y);
       int pixelAlpha = Color.alpha(pixelColor);
       
       int pixelRed = Color.red(pixelColor) + brightnessValue;
       int pixelGreen = Color.green(pixelColor) + brightnessValue;
       int pixelBlue = Color.blue(pixelColor) + brightnessValue;
       
       if(pixelRed > 255){
        pixelRed = 255;
       }else if(pixelRed < 0){
        pixelRed = 0;
       }
       
       if(pixelGreen > 255){
        pixelGreen = 255;
       }else if(pixelGreen < 0){
        pixelGreen = 0;
       }
       
       if(pixelBlue > 255){
        pixelBlue = 255;
       }else if(pixelBlue < 0){
        pixelBlue = 0;
       }

       int newPixel = Color.argb(
         pixelAlpha, pixelRed, pixelGreen, pixelBlue);
       
       dest.setPixel(x, y, newPixel);
       
      } 
     }
     return dest; 
    }

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />
    <ScrollView 
        android:layout_width="fill_parent"
        android:layout_height="fill_parent">
        <LinearLayout 
            android:layout_width="fill_parent"
         android:layout_height="fill_parent"
         android:orientation="vertical" >
         <TextView
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:text="Original" />
      <ImageView
          android:id="@+id/source" 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content" 
          android:src="@drawable/testpicture"/>
      <TextView
             android:layout_width="fill_parent"
             android:layout_height="wrap_content"
             android:text="Result" />
      <ImageView
          android:id="@+id/imageAfter" 
          android:layout_width="wrap_content"
          android:layout_height="wrap_content" />
   <SeekBar
       android:id="@+id/brightnessBar"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:max="512"
       android:progress="255"/>
   <TextView
       android:id="@+id/brightnessText"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="0"/>
   <Button
       android:id="@+id/doProcess"
       android:layout_width="fill_parent"
       android:layout_height="wrap_content"
       android:text="Do Process"/>
     </LinearLayout>
 </ScrollView>
</LinearLayout>

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