EURASIP Journal on Applied Signal Processing 
Volume 2003 (2003), Issue 5, Pages 430-436
doi:10.1155/S1110865703211069

An Approach to Adaptive Enhancement of Diagnostic X-Ray Images

Hakan Öktem,1 Karen Egiazarian,1 Jarkko Niittylahti,2 and Juha Lemmetti2

 1Institute of Signal Processing, Tampere University of Technology, P.O. Box 553, Tampere 33101, Finland
2Atostek Ltd., Hermiankatu 8D, Tampere FIN-33720, Finland
Received 31 January 2002; Revised 3 October 2002

Abstract

Digital radiography is a popular diagnostic imaging method. Denoising and enhancement have an important potential in obtaining as much easily interpretable diagnostic information as possible with reasonable absorbed doses of ionising radiation. Due to the increasing usage of high resolution and high precision images with a limited number of human experts, the computational efficiency of the denoising and enhancement becomes important. In this paper, a local adaptive image enhancement and simultaneous denoising algorithm for fulfilling the requirements of digital X-ray image enhancement is introduced. The algorithm is based on modification of the wavelet transform coefficients by a pointwise nonlinear transformation and reconstructing the enhanced image from the modified wavelet transform coefficients. The implementation of algorithm in software is simple, quick, and universal.