Center weighted median filters and their applications to image enhancement

Author

Ko, Sung-Jea ; Lee, Yong Hoon

Author_Institution

Dept. of Electr. & Comput. Eng., Michigan Univ., Dearborn, MI, USA

Volume

38

Issue

9

fYear

1991

fDate

9/1/1991 12:00:00 AM

Firstpage

984

Lastpage

993

Abstract

The center weighted median (CWM) filter, which is a weighted median filter giving more weight only to the central value of each window, is studied. This filter can preserve image details while suppressing additive white and/or impulsive-type noise. The statistical properties of the CWM filter are analyzed. It is shown that the CWM filter can outperform the median filter. Some relationships between CWM and other median-type filters, such as the Winsorizing smoother and the multistage median filter, are derived. In an attempt to improve the performance of CWM filters, an adaptive CWM (ACWM) filter having a space varying central weight is proposed. It is shown that the ACWM filter is an excellent detail preserving smoother that can suppress signal-dependent noise as well as signal-independent noise

Keywords

adaptive filters; filtering and prediction theory; interference suppression; picture processing; statistical analysis; additive white noise; center weighted median; detail preserving smoother; image enhancement; impulsive-type noise; median filters; noise suppression; signal-dependent noise; signal-independent noise; space varying central weight; statistical properties; Adaptive filters; Additive noise; Additive white noise; Character recognition; Degradation; Filtering; Image enhancement; Image recognition; Noise reduction; Smoothing methods;

fLanguage

English

Journal_Title

Circuits and Systems, IEEE Transactions on

Publisher

ieee

ISSN

0098-4094

Type

jour

DOI

10.1109/31.83870

Filename

83870