Download Image Enhancement Techniques

The ICE Tool
Feng Wen
Qi Yuan
Kin Wah Leung
Presentation Overview
 Project goal
 Interactive GUI
 Introduce image enhancement techniques
 Integration with Matlab™
 Implementation of image enhancement
techniques
 Potential advancement of ICE tool
ICE Tool
What is ICE tool?
 ICE = Image Contrast Enhancement
 Capable of executing various image enhancement techniques
 Provides easy to use interface
 Can be altered according to desire needs if necessary
Project Goal
 To implement an interactive GUI capable of enhancing
images
Research image enhancement techniques
 Programming an interactive GUI


Integrating with Matlab™ libraries

Implementing image enhancement functions

make sure functions performed correctly
Interactive GUI
 The Interactive GUI (graphic user interface)
As user friendly as possible
 Created using Java™
- A programming language from Sun Microsystems
- Provides great system portability
 Created as a Java™ frame application

 GUI features
Ability to load and save desired images
 Displays original and modified image on the same panel
 Easy menu bar browsing

GUI Features
Ability to load and save image
 Ability to display both original and modified image
on same screen

GUI Features (cont…)
Easy toolbar browsing
 Combines simple image enhancement methods

Image Enhancement Techniques
 Contrast Enhancement
Histogram equalization
- Image quality can be improved by altering histogram
- Calculates the ideal transformation from the
histogram of the image
- All gray levels used has a tendency to enhance image
contrast

Transformation Function:
T( f ) 

f
0
Pf ( w)dw
T(f ) can be calculated from the following relation:
gk  T ( fk ) 
k
p
j 0
f
( fj) 
k
Nj
j 0
N

Image Enhancement Techniques (cont…)
 Noise Removal Filter – removes dots or speckles on image
(equivalent of low-pass filtering)
Average Filter (Mean)
- Replace each pixel by the average of the window area pixels
- Has the effect of smoothing image
- Larger window size removes noise more effectively while
- At the expense of blurring the details
 Median Filter
- Replace each pixel by the median of the window area pixels
- More effective against impulse noise (aka salt and pepper)
- Can retain details and edges better than averaging filter

Image Enhancement Techniques (cont…)
 Deblurring
Wiener Deblurring
- Generalized inverse filter
- Effective when information regarding frequency
characteristics are known, at least to a degree
 Lucy-Richardson
- Effective when the PSF (point-spread function) is know but
little information is available for the noise

 Sharpening
Enhances details and edges
 Line structures can be obtain by applying high-pass filter

Integration With Matlab™
 Benefits

Allows the access of the large Matlab™ function library
- The Matlab™ math function library
- The Matlab™ image processing function library
 Integration process
Use of an software engine to link Matlab ™ and Java ™ GUI
together
 Implement the functions to the appropriate buttons

Integration With Matlab™
 Incorporate with JMatLink
A Java engine capable of linking Java ™ applications and Matlab ™
- Use of native methods, no source code need to be changed
- Created by Stefan Muller http://www.held-mueller.de/JMatLink/
 Edit autoexec.bat to set path to Matlab ™ and Java ™

Image Enhancement Implementation
 Research Matlab ™ code
Must know the codes for executing all of the image enhancement
techniques
 Ex: for histogram equalization
I = imread(‘abc.jpg’);
J = histeq( I );

 Implement the code to the Java ™ interface buttons
Every component assigned the appropriate Matlab ™ code
 Press of buttons send Java ™ code to Matlab ™ for execution

Image Enhancement Implementation
(cont…)
Summary
 Successfully creating an functional interactive GUI using
Java
 Java was integrated with Matlab™ through JMatLink
 The Matlab™ code was associated with every button in GUI
 Additional features and improvements can be made
Future Advancement of ICE Tool
 Try to make it a standalone application without Matlab™
 Addition of more image enhancement techniques
 Addition of more features such as help documentation,
zoom, etc
 Package into an easy to install application