Copyright © 2008 The Institute of Electronics, Information and Communication Engineers
Regular Section -- Papers -- Digital Signal Processing |
Filtering in Generalized Signal-Dependent Noise Model Using Covariance Information
1 The author is with the Faculty of Education, Kagoshima University, Kagoshima-shi, 890-0065 Japan. E-mail: nakamori{at}edu.kagoshima-u.ac.jp, 2 The authors are with the Department of Statistics, Granada University, 18071 Granada, Spain.
| Abstract |
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In this paper, we propose a recursive filtering algorithm to restore monochromatic images which are corrupted by general dependent additive noise. It is assumed that the equation which describes the image field is not available and a filtering algorithm is obtained using the information provided by the covariance functions of the signal, noise that affects the measurement equation, and the fourth-order moments of the signal. The proposed algorithm is obtained by an innovation approach which provides a simple derivation of the least mean-squared error linear estimators. The estimation of the grey level in each spatial coordinate is made taking into account the information provided by the grey levels located on the row of the pixel to be estimated. The proposed filtering algorithm is applied to restore images which are affected by general signal-dependent additive noise.
Key Words: film-grain noise, generalized signal-dependent noise, image filtering, covariance information
Manuscript received October 24, 2006. Manuscript revised October 25, 2007.