|
|
Multimodal retinal image registration
Štohanzlová, Petra ; CSc, Tomáš Suk, (referee) ; Harabiš, Vratislav (advisor)
This work deals with possibilities of registration of retinal images from different mo-dalities, concretely optical coherence tomography (OCT), scanning laser ophthalmoscopy (SLO) and fundus camera. In first stage is the interest focused on registration of SLO and fundus images, which will serve to determine area of interest for consecutive registration of OCT data. The final stage is finding correct location of OCT B-scans in fundus image. On the basis of the studied methods of registration was chosen method making use of computation of correlation coefficient for both cases. For finding optimal parameters of registration is used searching through whole space of parameters. In partial stages of the work was created algorithm for alignment of B-scans followed by detection of blood vessels and also simple algorithm for detection of blood vessels from fundus image. For more transparent registration the graphical user interface was created, which allows loading input images and displaying the result in several possible forms.
|
|
|
Retinal image registration using phase correlation
Šikula, Viktor ; Harabiš, Vratislav (referee) ; Kolář, Radim (advisor)
This master thesis deals with retinal image registration using phase correlation technique. There are described properties of retinal images and modality of scanning. A geometrical transformation encompasing scale, rotation and translation between two retinal images is considered and the whole registration framework is described. There are used retinal images from fundus camera and scanning laser ophthalmoscope (SLO). In this thesis is described corresponding bifurcations detection using phase correlation and registration using second-order polynomial transformation. The results are subjectively and objectively verificated.
|
|
|
Automatic detection of neural fibers losses
Václavek, Martin ; Jiřík, Radovan (referee) ; Kolář, Radim (advisor)
This work is focused on detection of loss in nerve fibre layer on colour pictures of retina, witch are makes by fundus camera. It describe every simple objects of retina, optic nerve head, macula lutea and vascular bed. It detect optic nerve head and his near area, witch is general for detection of breakdownds. It use several metodes of picture adjusting for picture elaboration and objects detection (segmentation, thresholding, enhancement, hough transformation ). The detection of loss in nerve fibre layer is based on comparing of statistic parameters ( average, standart deviation, skewness coefficient and kurtosis coefficient histogram, entropy ) in choosed areas with and withou destruction of nerve layers. Vascular bed have badwatsh on results, cause of this we using hand choosing of essay.
|
|
|
Texture analysis of retinal images
Mikauš, Jakub ; Odstrčilík, Jan (referee) ; Gazárek, Jiří (advisor)
The thesis deals with the detection of the nerve fiber layer disruptions in retina scans. The introduction presents an overview of the human eye fysiology and analyses the input image data. The thesis continues with an investigation of two texture analysis methods. While the method of adapted filters does not produce very good results, the method of brightness assessment is shown to work satisfactorily. The final part of the thesis describes the implemented tool for the detection of the nerve fiber layer disruptions.
|
|
|
A Classification Methods for Retinal Nerve Fibre Layer Analysis
Zapletal, Petr ; Kolář, Radim (referee) ; Odstrčilík, Jan (advisor)
This thesis is deal with classification for retinal nerve fibre layer. Texture features from six texture analysis methods are used for classification. All methods calculate feature vector from inputs images. This feature vector is characterized for every cluster (class). Classification is realized by three supervised learning algorithms and one unsupervised learning algorithm. The first testing algorithm is called Ho-Kashyap. The next is Bayess classifier NDDF (Normal Density Discriminant Function). The third is the Nearest Neighbor algorithm k-NN and the last tested classifier is algorithm K-means, which belongs to clustering. For better compactness of this thesis, three methods for selection of training patterns in supervised learning algorithms are implemented. The methods are based on Repeated Random Subsampling Cross Validation, K-Fold Cross Validation and Leave One Out Cross Validation algorithms. All algorithms are quantitatively compared in the sense of classication error evaluation.
|
|
|
Detection of the retinal nerve fibre layer
Kunc, Martin ; Szabó, Zoltán (referee) ; Kolář, Radim (advisor)
This thesis is deals with the nerve fibre layer in the colour ophthalmology images of retina. The thesis describes how can we use finding of nerve fibre layer and how was it solved in the past. In the thesis are proposed the methods that are based on processing and scoring frequency spectrums of individual sample of retina. At first here are described the methods of detection on the artificial generated samples that just simulate the nerve fibre layer. Then the thesis concentrates on processing of real images of retina. Because of the bloodstream, that depreciates processing at real images, are all surveyed samples are chosen manually. Except detection the nerve fibre layer itself, the thesis also deals with determination of direction their dissemination.
|
|
|
Retinal Biometry for Human Recognition
Sikorová, E.
This paper deals with recognition of a person by comparing symptom sets extracted from images of the retinal vessels pattern. In the practical part there were realized algorithms for human identification with the method of nearest neighbor search (NS), extended NS including more symptoms and template matching, for which MATLAB program was used. The work includes testing of suggested programs on the biometric database of symptomatic vectors with the following evaluation.
|
|
|
Vulnerability assesment tools
Charvát, Michal ; Veber, Jaromír (advisor) ; Klíma, Tomáš (referee)
This bachelor thesis is focused on a specific area of information systems security, which is called vulnerability assesment. Vulnerability assesment is executed with special tools called vulnerability scanners. In the the beginning of the first part I will introdukce the area of information systems security and its breaf history, the basic terms of vulnerability assesment and related topics, such as penetration testing. In the following part few test will be executed using some of the chosen available and free tools and then analyze its results. The main criteria will be the number and criticality of the given vulnerabilities. Finally the user-friedly aspect of each tool will be evalueted, which could be a little subjective matter.
|
|
|
Vulnerability Management in the Corporate IT Infrastructure
Hronek, Tomáš ; Veber, Jaromír (advisor) ; Klíma, Tomáš (referee)
The present thesis deals with the area of vulnerability management and its relation to information security. Its main purpose is to set the topic of vulnerability management in context of company information security and to explain its relationship to related disciplines. In the practical part, selected vulnerability assessment tools are compared and methodology is applied to determine the criticality of the vulnerabilities identified in relation to the provided IT services. The objectives were achieved by literature review, personal consultations with employees responsible for information security at J&T Bank and by comparing the results of several tools for assessing vulnerability (Nessus, Retina, OpenVAS, Nexpose, Tripwire). To date, there has not been published a thesis devoted exclusively to the topic of vulnerability management. This thesis is the first one to provide comparable results of vulnerability scanning of the same targets. Equally valuable is the application of Common Vulnerability Scoring System to determine the criticality of the vulnerabilities identified in relation to delivered IT services.
|
|
| |
guest ::
