Set brightness of the image(increase,decrease) in ImageView (Android)

Before Brightness change

After Brightness Change

brightness 50

brightness 90

brightness -40

brightness -60

brightness -80

Create new Android Project

Project Name: PlayingwithBitmaps

Build Target: Android 2.3.3   //or greater than that

Application Name: PlayingwithBitmaps

Package Name: com.hamad.playingwithbitmaps

Create Activity: Main

Min SDK: 10 // or greater than that

  1.create main layout:

• One image view to display the image.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#000000"
    android:id="@+id/rlMain" >

    <ImageView
        android:id="@+id/imViewAndroid"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:src="@drawable/beautiful" />

</RelativeLayout>

 2. code of main activity:

package com.shaikhhamadali.blogspot.playingwithbitmaps;

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

public class Main extends Activity {
    ImageView imViewAndroid;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        imViewAndroid = (ImageView) findViewById(R.id.imViewAndroid);
        imViewAndroid.setImageBitmap(SetBrightness(BitmapFactory.decodeResource(getResources(), R.drawable.android_droid),-80));
 }
 
 public Bitmap SetBrightness(Bitmap src, int value) {
     // original image size
     int width = src.getWidth();
     int height = src.getHeight();
     // create output bitmap
     Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
     // color information
     int A, R, G, B;
     int pixel;
  
     // scan through all pixels
     for(int x = 0; x < width; ++x) {
         for(int y = 0; y < height; ++y) {
             // get pixel color
             pixel = src.getPixel(x, y);
             A = Color.alpha(pixel);
             R = Color.red(pixel);
             G = Color.green(pixel);
             B = Color.blue(pixel);
  
             // increase/decrease each channel
             R += value;
             if(R > 255) { R = 255; }
             else if(R < 0) { R = 0; }
  
             G += value;
             if(G > 255) { G = 255; }
             else if(G < 0) { G = 0; }
  
             B += value;
             if(B > 255) { B = 255; }
             else if(B < 0) { B = 0; }
  
             // apply new pixel color to output bitmap
             bmOut.setPixel(x, y, Color.argb(A, R, G, B));
         }
     }
  
     // return final image
     return bmOut;
 }
}

  3. note that:

• Refer to this Wiki page on Brightness to get the concepts and ideas:Brightness
• With the help of this,SetBrightness() method you can set the Brightness of image (increase,decrease) on click,on action_down etc.

  4. conclusion:

• Some deep information about Brightness.
• Know how to set brightness of an image bitmap from drawables.

  5. About the post:

•  The code seems to explain itself due to comments, and is very easy to understand.
•  Don’t mind to write a comment whatever you like to ask, to know,to suggest or recommend.
•  Hope you enjoy it!

6. Source Code:

        you can download the source code here

Cheers,

Hamad Ali Shaikh