Introduction

Image Filter allows you to add various effects on image. There are mainly two purpose of Image Processing:

1. Image Understanding: It is used to identify content of image, weather image has human faces, objects (bus, train, etc.), measure dimension of objects,etc. OpenCV (Open Source Computer Vision Library) is one of the main library used for Image Understanding.
2. Image Beautify : It is used to beautify image by adding different filters, adjust colour, adjust contrast, etc..

Android provides two options for Image Filters/Processing

1. Using SDK with Java Code,Android SDK has “android.graphics” package which contains classes related to Image Processing.
2. Using NDK with C/C++ Code.

List of classes from android.graphics

• Bitmap
• BlurMaskFilter
• Canvas
• Color
• LinearGradient
• Matrix
• Paint
• PorterDuff
• PorterDuffXfermode
• Rect
• RectF
• Shader

Application

This article explains simple Android application which demonstrates 30 different image filters. Application has one button to select image from gallery, bottom strip contains visual representation of effect then simply click on effect to apply into your selected photo. Application will apply selected effect and store image in root folder of SDCard with effect name. The entire logic of Image filter/processing is written in pure java (without NDK/C++).

Application Screen shots

Image source : http://www.theotherhome.com/images/PackageImages/Large/2013-03-0811-37-01.jpg

👁 device-2013-08-30-104130
👁 device-2013-08-30-104059

Different image filters available in Application

👁 effect_watermark
👁 effect_tint

👁 effect_smooth
👁 effect_sheding_yellow

👁 effect_grayscale
👁 effect_sheding_green

👁 effect_sheding_cyan
👁 effect_sheding

👁 effect_sepia_green
👁 effect_sepia_blue

👁 effect_sepia
👁 effect_saturation

👁 effect_round_corner
👁 effect_mean_remove

👁 effect_invert
👁 effect_hue

👁 effect_gaussian_blue
👁 effect_flea

👁 effect_engrave
👁 effect_emboss

👁 effect_contrast
👁 effect_color_red

👁 effect_gamma
👁 effect_color_green

👁 effect_color_depth_64
👁 effect_color_depth_32

👁 effect_color_blue
👁 effect_brightness

👁 effect_boost_3
👁 effect_boost_2

👁 effect_boost_1
👁 effect_black

• Download Source Code

I would like to thanks Mr Peter Huston (http://petehouston.com/) for providing Android Image Filters tutorials in his blog.

Original Source Code: http://xjaphx.wordpress.com/learning/tutorials/

Resources

1. http://www.jhlabs.com/ip/filters/
2. http://developer.android.com/reference/android/media/effect/EffectFactory.html
3. https://code.google.com/p/android-image-filtering/
4. http://xjaphx.wordpress.com/learning/tutorials/
5. https://code.google.com/p/android-image-filtering/
6. https://github.com/ragnraok/android-image-filter