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Optical disc detection in ophthalmologic images
Melša, Ondřej ; Harabiš, Vratislav (referee) ; Kolář, Radim (advisor)
This work is target on the detection of center and border of optical disk in AF (autofluorescent) and IR (infrared) images. The image are primarily modified at brightness area. The center of optical disk are sought after by algorithms, which offers program Matlab. As well are search border of optical disk. Results are comparison with engaged results and then is calculated effectivity of created algorithm.
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Methods for texture analysis in ophthalmologic images
Hanyášová, Lucie ; Szabó, Zoltán (referee) ; Kolář, Radim (advisor)
This thesis is focused on texture analysis methods. The project contains an overview of widely used methods. The main aim of the thesis is to develop a method for texture analysis of retinal images, which will be used for distinction of two patient groups, one with glaucoma eyes and one healthy. It is observed that glaucoma patients don´t have a texture on the eye ground. Preprocessing of the images is found by transfer of the image to different color spaces to achieve the best emphasis of the eye ground texture. Co-occurrence matrix is chosen for texture analysis of this data. The thesis contains detail description of the chosen solutions and feature discussion and the result is a list of features, which can be used for distinction between glaucoma and healthy eyes. The method is implemented in Matlab environment.
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Segmentation in the color fundus imges
Malínský, Miloš ; Jiřík, Radovan (referee) ; Kolář, Radim (advisor)
Optic nerve head and macula are important structures in fundus images. Detection and measurement plays crucial role in several diagnosis methods of optic disease. This work is focused on the detection of the central point of macula and optic nerve head, where the inner border is detected too. There are many methods for extracting this structure in retinal images. Due to the unique properties of each acquisition technique, a single generally acknowledged detection algorithm does not exist. The whole detection process is described from preprocessing through segmentation towards postprocessing. Presented methods are based on the combination of correlation techniques, Hough transform, active contours and morphological operations. The detected contours of the optic nerve head are evaluated and quantitatively compared with the contour drawn by experienced ophthalmologist. The master thesis contains quantity of images that help to describe detection methods.
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Image database system for glaucoma diagnosis support
Peter, Roman ; Roleček, Jiří (referee) ; Kolář, Radim (advisor)
Tato práce popisuje přehled standardních a pokročilých metod používaných k diagnose glaukomu v ranném stádiu. Na základě teoretických poznatků je implementován internetově orientovaný informační systém pro oční lékaře, který má tři hlavní cíle. Prvním cílem je možnost sdílení osobních dat konkrétního pacienta bez nutnosti posílat tato data internetem. Druhým cílem je vytvořit účet pacienta založený na kompletním očním vyšetření. Posledním cílem je aplikovat algoritmus pro registraci intenzitního a barevného fundus obrazu a na jeho základě vytvořit internetově orientovanou tři-dimenzionální vizualizaci optického disku. Tato práce je součásti DAAD spolupráce mezi Ústavem Biomedicínského Inženýrství, Vysokého Učení Technického v Brně, Oční klinikou v Erlangenu a Ústavem Informačních Technologií, Friedrich-Alexander University, Erlangen-Nurnberg.
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Jiří Wolf Measurement of the properties of ultrasound system
Wolf, Jiří ; Čížek, Martin (referee) ; Kolář, Radim (advisor)
This diploma thesis deals with the displaying process evaluation from the resolution capabilities of the ultra-sonic probe point of view. As a part of the thesis a method for measuring the response from point spread function (PSF) and method for measuring the response from linear spread function LSF were designed. Collected data were processed in the Matlab environment. Basic evaluation parameters of the space resolution capabilities were set and used – axial, lateral and traversal resolution.
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Registration of the autofluorescence images
Říha, František ; Harabiš, Vratislav (referee) ; Kolář, Radim (advisor)
The autofluorescence images of the retina, which are obtained by laser scanning confocal ophthalmoscope Heidelberg Retina Angiograph (HRA), are used for early glaucoma diagnosis. Glaucoma is caused by gradual damage of the optic nerves, which leads to the failing of eyesight and can even cause its complete loss. HRA system is used to obtain a set of retinal images, where every image represents certain segment of retina. This thesis describes image registration methods for retinal image mosaicing. The tested registration methods are based on the global function of similarity or the landmarks detection. As landmarks, the blood vessel bifurcations are considered.
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Modelling of the Visual Perception
Faruga, Michal ; Hemzal, Dušan (referee) ; Kolář, Radim (advisor)
This diploma thesis considers with human vision and human eye. It takes into account both anatomic view and physiology standpoints. There is, among others, description of optical processes occurring in the organ of the sight mentioned in the work. The human eye suffers from optical defects – aberrations – that are able to degrade the retinal image and ultimately visual performance. Substantial part of the text deals with these aberrations. There are also analysed possibilities of their elimination using an inverse aberration. Work also assumes opportunity to optical modeling to calculate distorted images from ocular aberration data. Practical part consist of software application created using Matlab environment ver. 6.5 as well as full documentation. The examples of outputs procured using this application are published. Both software application and detail documentation are included on CD.
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Filtering of the ECG Signals
Slezák, Roman ; Kolář, Radim (referee) ; Kozumplík, Jiří (advisor)
Main objective of this thesis was to learn about possibility of suppression of narrow band disturbances. We focused on use of Lynn’s filters. The objective was to realize these filters with respect to a fast algorithm of filtering. Concretely, for suppression of drift we realized the fast high pass filter with flexible cut off frequency. Then we realized filter for suppression of electrical network disturbance. We have realized these filters for sampling frequencies 250 and 500 Hz and we tested them with real ECG signals. Then we have evaluated their efficiency.
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Detection of the nerve fibres in ophthalmologic images
Urbánek, Dušan ; Harabiš, Vratislav (referee) ; Kolář, Radim (advisor)
This thesis deals with detection of the retinal nerve fiber layer in gray level retinal images taken by fundus camera. The first part describes a physiology of human eye and glaucoma disease. Then, the use of wavelet transform and algorithm of texture analysis applied for texture analysis. Next chapters describe theory of texture analysis named „Gray level run length matrices“ and its application for detection of the nerve fiber layer. Applications of this method are described for three types of retinal tissues and for whole image. The last chapter describes gray levels around optic disc and results obtained from parameters from GLRL matrices.
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Biofeedback in therapy
Ticháček, Aleš ; Kolář, Radim (referee) ; Kolářová, Jana (advisor)
Diploma thesis – the Biological feedback in therapy deals with electromyography (EMG), investigative techniques based on electromyography, myofeedback applications and intention controlled myofeedback (IMF therapy). Electromyography is described on principal and there are used electrodes presented. In investigative methods are mentioned their basic progress at investigation by the help of elektromyography. Next are present artifacts, which in the elektromyography signal values. For myofeedback I worked up basic study. Myofeedback is based principle in IMF therapy. The effect of IMF therapy was verified with synchronized signal electroencephalograph (EEG) and EMG. In concrete I worked with movement-related cortical potentials (MRCP) components and Bereitschaftspotential (BP). BP presents highlight component from MRCP and alone BP precluding fulfillment movement. It was tested on metering, that BP occur before executed movement. Idea IMF therapy is correct.
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