we propose a method for medical image denoising using calculus of variations and local variance estimation by shaped windows. this method reduces any additive noise and preserves small patterns and edges of images. a pyramid structure-texture decomposition of images is used to separate noise and texture components based on local variance measures. the experimental results show that the proposed...

Data Denoising by Noise Invalidation c © Nima Nikvand, 2008 Master of Applied Science (MASc) Department of Electrical and Computer Engineering Ryerson University In this thesis, the problem of data denoising is studied, and two new denoising approaches are proposed. Using statistical properties of the additive noise, the methods provide adaptive data-dependent soft thresholding techniques to re...

The aim of this study was to evaluate the contribution of peripheral and central factors to the development of visual sensitivity. We used the approach of (Pelli, 1981, 1990) to evaluate the hypothesis that intrinsic noise is high in infants compared with adults, and therefore sets an important limit on contrast sensitivity in infants. We measured contrast thresholds in the presence of various ...

The present work studies the effect of additive noise on two high-dimensional systems. The first system under study is two-dimensional, evolves close to the deterministic stability threshold and exhibits an additive noise-induced shift of the control parameter when driving one variable by uncorrelated Gaussian noise. After a detailed analytical and numerical study of this effect, the work furth...

We propose a method for solving linear space-time variant blind source separation (BSS) problem with additive noise, x=As+n, on the “pixelby-pixel” basis i.e. assuming that unknown mixing matrix is different for every space or time location. Solution corresponds with the isothermal-To equilibrium of the free energy H =U-ToS contrast function where U represents the input/output energy exchange a...

We shall present in this paper the results of investigations on the perfor— mance of Linear Prediction (LP) analysis of speech when the signal is corrupted with additive white noise. In particular we shall discuss the effect of noise on various parameters derived from LP analysis. Theoretical justification for U 10 the observed results is given.

Many digital steganographic systems employ the capacity of an additive white Gaussian noise (WGN) channel as a performance metric. We present results that show that this capacity metric understates the capacity potential of these systems and propose a more accurate measure based on the arbitrary noise channel. This measure is compared to the capacity of the additive WGN channel and the performa...

Multiplicative noise, also known as speckle noise, is signal dependent and difficult to remove. Based on a fourth-order PDE model, this paper proposes a novel approach to remove the multiplicative noise on images. In practice, Fourier transform and logarithm strategy are utilized on the noisy image to convert the convolutional noise into additive noise, so that the noise can be removed by using...