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Abstract book (pdf) - ICPR 2010

Abstract book (pdf) - ICPR 2010

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The goal of this paper is the development of a novel approach for the problem of Noise Removal, based on the theory of<br />

Reproducing Kernels Hilbert Spaces (RKHS). The problem is cast as an optimization task in a RKHS, by taking advantage<br />

of the celebrated semi parametric Representer Theorem. Examples verify that in the presence of gaussian noise the proposed<br />

method performs relatively well compared to wavelet based techniques and outperforms them significantly in the presence<br />

of impulse or mixed noise.<br />

13:50-14:10, Paper WeBT4.2<br />

Multichannel Image Regularisation using Anisotropic Geodesic Filtering<br />

Grazzini, Jacopo, Los Alamos National Lab.<br />

Soille, Pierre, Ec. Joint Res. Centre<br />

Dillard, Scott, Los Alamos National Lab.<br />

This paper extends a recent image-dependent regularisation approach introduced in [Grazzini and Soille, PR09&CCIS09]<br />

aiming at edge-preserving smoothing. For that purpose, geodesic distances equipped with a Riemannian metric need to be<br />

estimated in local neighbourhoods. By deriving an appropriate metric from the gradient structure tensor, the associated geodesic<br />

paths are constrained to follow salient features in images. Following, we design a generalised anisotropic geodesic<br />

filter, incorporating not only a measure of the edge strength, like in the original method, but also further directional information<br />

about the image structures. The proposed filter is particularly efficient at smoothing heterogeneous areas while preserving<br />

relevant structures in multichannel images.<br />

14:10-14:30, Paper WeBT4.3<br />

Local Jet based Similarity for NL-Means Filtering<br />

Manzanera, Antoine, ENSTA-ParisTech<br />

Reducing the dimension of local descriptors in images is useful to perform pixels comparison faster. We show here that, for<br />

computing the NL-means denoising filter, image patches can be favourably replaced by a vector of spatial derivatives (local<br />

jet), to calculate the similarity between pixels. First, we present the basic, limited range implementation, and compare it with<br />

the original NL-means. We use a fast estimation of the noise variance to automatically adjust the decay parameter of the<br />

filter. Next, we present the unlimited range implementation using nearest neighbours search in the local jet space, based on<br />

a binary search tree representation.<br />

14:30-14:50, Paper WeBT4.4<br />

Image Denoising based on Fuzzy and Intra-Scale Dependency in Wavelet Transform Domain<br />

Saeedi, Jamal, Amirkabir Univ. of Tech.<br />

Moradi, Mohammad Hassan, Amirkabir Univ. of Tech.<br />

Abedi, Ali, Amirkabir Univ. of Tech.<br />

In this paper, we propose a new wavelet shrinkage algorithm based on fuzzy logic. Fuzzy logic is used for taking neighbor dependency and<br />

uncorrelated nature of noise into account in wavelet-based image denoising. For this reason, we use a fuzzy feature for enhancing wavelet coefficients<br />

information in the shrinkage step. Then a fuzzy membership function shrinks wavelet coefficients based on the fuzzy feature. We<br />

examine our image denoising algorithm in the dual-tree discrete wavelet transform, which is the new shiftable and modified version of discrete<br />

wavelet transform. Extensive comparisons with the state-of-the-art image denoising algorithm indicate that our image denoising algorithm<br />

has a better performance in noise suppression and edge preservation.<br />

14:50-15:10, Paper WeBT4.5<br />

Noise-Insensitive Contrast Enhancement for Rendering High-Dynamic-Range Images<br />

Lin, Hsueh-Yi Sean, Lunghwa Univ. of Science and Tech.<br />

The process of compressing the high luminance values into the displayable range inevitably incurs the loss of image contrasts. Although the<br />

local adaptation process, such as the two-scale contrast reduction scheme, is capable of preserving details during the HDR compression<br />

process, it cannot be used to enhance the local contrasts of image contents. Moreover, the effect of noise artifacts cannot be eliminated when<br />

the detail manipulation is subsequently performed. We propose a new tone reproduction scheme, which incorporates the local contrast enhancement<br />

and the noise suppression processes, for the display of HDR images. Our experimental results show that the proposed scheme is<br />

indeed effective in enhancing local contrasts of image contents and suppressing noise artifacts during the increase of the visibility of HDR<br />

scenes.<br />

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