Image segmentation based on variational techniques

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2006

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Duramaz, Alper

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Recently, solutions to the problem of image segmentation and denoising are developed based on the Mumford-Shah model. The model provides an energy functional, called the Mumford-Shah functional, which should be minimized. Since the minimization of the functional has some difficulties, approximate approaches are proposed. Two such methods are the gradient flows method and the Chan-Vese active contour method. The performance evolution in terms of speed shows that the gradient flows method converges to the boundaries of the smooth parts faster; but for the hierarchical four-phase segmentation, it is observed that this method sometimes gives unsatisfactory results. In this work, a fast hierarchical four-phase segmentation method is proposed where the Chan-Vese active contour method is applied following the gradient flows method. After the segmentation process, the segmented regions are denoised using diffusion filters. Additionally, for the low signal-to-noise ratio applications, the prefiltering scheme using nonlinear diffusion filters is included in the proposed method. Simulations have shown that the proposed method provides an effective solution to the image segmentation and denoising problem.

Subject Keywords

Electrical Engineering., Electronics., Nuclear Engineering.

URI

http://etd.lib.metu.edu.tr/upload/12607721/index.pdf
https://hdl.handle.net/11511/16127

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

A. Duramaz, “Image segmentation based on variational techniques,” M.S. - Master of Science, Middle East Technical University, 2006.