the edges of an image define the image boundary. when the image is noisy, it does not become easy to identify the edges. therefore, a method requests to be developed that can identify edges clearly in a noisy image. many methods have been proposed earlier using filters, transforms and wavelets with ant colony optimization (aco) that detect edges. we here used aco for edge detection of noisy ima...

Papadimitriou Katerina. MSc, Computer Science Department, University of Ioannina, Greece. June, 2015. Tomographic image reconstruction with spatially varying mixture models. Thesis Supervisor: Christophoros Nikou. Image reconstruction is a mathematical process through which an accurate image of an object is reconstructed from multiple projections. Tomographic reconstruction strategies have gain...

introduction: ordered subset expectation maximization (osem), is an effective iterative method for spect image reconstruction. the aim of this study is the evaluation of the role of system matrix in osem image reconstruction method using four different physical beam radiation models with three detection configurations. methods: spect was done with an arc of 180 degree in 32 projections after i...

  Introduction: Ordered subset expectation maximization (OSEM), is an effective iterative method for SPECT image reconstruction. The aim of this study is the evaluation of the role of system matrix in OSEM image reconstruction method using four different physical beam radiation models with three detection configurations. Methods: SPECT was done with an arc of 180 deg...

This paper presents an algorithm for noise removal from digital image, based on stochastic noise pattern. We apply white Gaussian noise to improve the quality of the noisy input image to get the de -noised response image. Input noisy image is subjected to independent additive white Gaussian noise of different standard deviation, the output image corresponding to individual noise standard deviat...

The purpose of this study was to analyze the behavior of a contouring algorithm for PET images based on adaptive thresholding depending on lesions size and target-to-background (TB) ratio under different conditions of image reconstruction parameters. Based on this analysis, the image reconstruction scheme able to maximize the goodness of fit of the thresholding algorithm has been selected. A ph...

Panoptic is a custom spherical light field camera used as a polydioptric system where imagers are distributed over a hemispherical surface, each having its own vision of the surroundings and a distinct focal plane. The spherical light field camera records light information from any direction around its center. This paper revises previously developed Nearest Neighbor and Linear blending techniqu...

In this paper we propose an original study of the reconstruction of subband compressed images impaired by channel transmission errors. The method proceeds in two steps : first a detection scheme is applied to determine which coefficients of the subband decomposition have been affected by transmission, and then an estimation step tries to evaluate the erroneous coefficients. In our model, subban...