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Related Experiment Video

Updated: Jul 10, 2026

Transient Optical Clearing Using Absorbing Molecules for Ex Vivo and In Vivo Imaging

Transient Optical Clearing Using Absorbing Molecules for Ex Vivo and In Vivo Imaging

Published on: July 11, 2025

Fuzzy wavelet and contourlet based contrast enhancement.

Ehsan Nezhadarya¹, Mohammad B Shamsollahi, Omid Sayadi

¹Faculty of Electrical Engineering, Sahand University of Technology, Tabriz, Iran. e_arya@ee.sharif.edu

Conference Proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference

|December 6, 2007

Summary

This study introduces a novel fuzzy approach for image contrast enhancement using wavelet and contourlet transforms. The method effectively improves image details by enhancing coefficients in both transform domains.

Related Experiment Videos

Last Updated: Jul 10, 2026

Transient Optical Clearing Using Absorbing Molecules for Ex Vivo and In Vivo Imaging

Transient Optical Clearing Using Absorbing Molecules for Ex Vivo and In Vivo Imaging

Published on: July 11, 2025

Area of Science:

Image Processing
Computer Vision
Digital Signal Processing

Background:

Conventional 2D wavelet transforms struggle with representing line-shaped image features due to separability and non-directionality.
Contourlet transform offers a better alternative for sparse representation of directional features like curves and lines.

Purpose of the Study:

To develop and evaluate a fuzzy-based approach for image contrast enhancement.
To leverage the strengths of both wavelet and contourlet transforms for improved image representation and enhancement.
To create a flexible and understandable enhancement procedure incorporating expert knowledge.

Main Methods:

A fuzzy approach is proposed for coefficient enhancement in both wavelet and contourlet transform domains.
Simple fuzzy rules are utilized to modify coefficients, enhancing image contrast.
The method is applied to separable (wavelet) and nonseparable (contourlet) transforms.

Main Results:

The proposed fuzzy approach demonstrates effectiveness in enhancing image contrast.
The method performs well in both wavelet and contourlet transform spaces.
Implementation results validate the efficacy of the fuzzy enhancement technique.

Conclusions:

The fuzzy approach offers an effective and flexible method for image contrast enhancement.
Utilizing fuzzy rules in wavelet and contourlet spaces significantly improves image quality.
This technique allows for the integration of expert knowledge into the enhancement process.