Title :
Medical image enhancement based on NSCT
Author :
Feng Zhou ; Xiuli Ma ; Yang Li ; Xiaojun Zhou
Author_Institution :
Sch. of Commun. & Inf. Eng., Shanghai Univ., Shanghai, China
Abstract :
A novel method for medical images enhancement based on NSCT and image statistical properties was proposed. Firstly, nonsubsampled contourlet transform provides a multiresolution and multi-direction analysis for the medical images. We use the nonsubsampled Laplace Pyramids to decompose the image into different scales, then use the nonsubsampled directional filter banks to decompose the image into different directions and estimate the noise variance of each subband. After modeling the coefficient of each directional subband and using generalized classification model according to the statistical property of the transform coefficients, they were categorized into strong edges, weak edges and noise by Bayesian classifier. A nonlinear mapping function was designed to enhance and suppress the different coefficients adaptively to obtain a good enhancement result with significant characters according to the modified coefficients of NSCT. Experimental results show that the proposed method is practicable and effective.
Keywords :
Bayes methods; Laplace transforms; image classification; image enhancement; image resolution; image sampling; image segmentation; medical image processing; statistical analysis; Bayesian classifier; NSCT coefficients; directional subband; generalized classification model; image decomposition; image statistical properties; medical image enhancement; multidirection analysis; multiresolution analysis; noise variance estimation; nonlinear mapping function; nonsubsampled contourlet transform; nonsubsampled directional filter bank; nonsubsampled pyramids; transform coefficients; weak edge; Bayes Threshold; Classification; Enhanced Function; Image Enhancement; Medical Image; NSCT; PSNR;
Conference_Titel :
Smart and Sustainable City 2013 (ICSSC 2013), IET International Conference on
Conference_Location :
Shanghai
Electronic_ISBN :
978-1-84919-707-6
DOI :
10.1049/cp.2013.2013