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Object Detection in Video Sequences
Šebela, Miroslav ; Beneš, Radek (referee) ; Číka, Petr (advisor)
The thesis consists of three parts. Theoretical description of digital image processing, optical character recognition and design of system for car licence plate recognition (LPR) in image or video sequence. Theoretical part describes image representation, smoothing, methods used for blob segmentation and proposed are two methods for optical character recognition (OCR). Concern of practical part is to find solution and design procedure for LPR system included OCR. The design contain image pre-processing, blob segmentation, object detection based on its properties and OCR. Proposed solution use grayscale trasformation, histogram processing, thresholding, connected component,region recognition based on its patern and properties. Implemented is also optical recognition method of licence plate where acquired values are compared with database used to manage entry of vehicles into object.
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Analysis of Colour Retinal Images Aimed at Segmentation of Vessel Structures
Odstrčilík, Jan ; Jiřík, Radovan (referee) ; Jan, Jiří (advisor)
Segmentation of vessel structure is an important phase in analysis of retinal images. The resulting vessel system description may be important for diagnostic of many eye and cardiovascular diseases. A method for automatic segmentation of the vessel structure in colour retinal images is presented in the thesis. The method utilises 2D matched filtering to detect presence of short linear vessel sections of a particular thickness and orientation. The approach correlates the local image areas with a 2D masks based on a typical brightness profile perpendicular to vessels of a particular width. Three different approximated profiles are used and corresponding matched filters are designed for: thin, medium and thick vessels. The evaluation of typical vessel profiles and filter design are described in chapter 3 and chapter 4. The parametric images obtained by convolution of the image with the masks are then thresholded in order to obtain binary representation of vessel structure. The three binary representations are consequently combined to provide the best available rough vessel map, which is finalised by complementing the obviously missing vessel sections and cleaning the disconnected fractional artefacts. The thresholding algorithm and final steps of processing are mentioned in chapter 5 and chapter 6. The method has been implemented by computer and the program for automatic vessel segmentation has been developed using database of real retinal images. The efficiency of the method has been finally evaluated on images from the standard database DRIVE.
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ECG signal filtering in the wavelet domain
Zedníček, Vlastimil ; Vítek, Martin (referee) ; Smital, Lukáš (advisor)
The aim of this work is introduction with the method of filtering the signal using wavelet transform. Our task was to use a redundant wavelet transform for filtering ECG signals. First we met with wavelet filtering. In the practical part, we implemented a filter based on redundant DTWT in Matlab. The results were evaluated based on the achieved signal / noise ratio. The proposed filter, we tested the CSE database, and we tried to optimize the filter parameters and the degree of decomposition of wavelet transform, the bank decomposition and reconstruction filters, thresholding methods and threshold setting. The results were evaluated based on the achieved signal / noise ratio. as a last resort, we compared the results obtained with the results of different filtering methods
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Segmentation of magnetic resonance images
Hanák, Pavel ; Harabiš, Vratislav (referee) ; Havlíček, Martin (advisor)
Segmentation, magnetic resonance, grey matter, white matter, thresholding, region growing, splitting and merging, watershed, level set method.
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Microaneurysms and hemorrhages detection in retinal images
Tobiášová, Nela ; Štohanzlová, Petra (referee) ; Kolář, Radim (advisor)
Diabetic retinopathy is a serious eye complication of diabetes mellitus and one of the major causes of blindness in the world. The microaneurysms and the haemorrhages are the pathologies of diabetic retinopathy. Their detection can halt or reverse the progression of this disease and prevent blindness. The algorithms could be helpful to ophthalmologists. This bacherol’s thesis is concerned with the detection of microaneurysms and haemorrhages in fundus images. The diabetic retinopathy, the types of lesions and the treatment methods are described in the first part of the paper. Existing methods are described as follows. The practical part of this work is aimed at the proposal and the detection of the red lesions. It consists of several steps, such as selecting the correct channel of RGB images, using local methods of contrast enhancement, edge detection, thresholding, creating a training set of the feature vector and the classification with the use of the neutral network.
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Segmentation of optic disc in retinal image data
Juráček, Radek ; Mézl, Martin (referee) ; Odstrčilík, Jan (advisor)
This bachelor thesis is focused on the algorithm of automatic detection of the optical disk in retinal images. It briefly describes the anatomy of the human eye and the principles of scanning the ocular background. The following describes the optical disk segmentation methods. Selected methods are implemented in MATLAB and optimized using a genetic algorithm. A total of five methods were introduced and optimized on the HRF dataset and two experimental datasets.
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Black and white documents conversion
Bárnet, Lukáš ; Červinka, Luděk (referee) ; Richter, Miloslav (advisor)
The Bachelor's paper is concerned with processing black-and-white, grey-toned documents, which means the conversion of grey-toned picture of the document into binary one. In the paper, the procedures of separating the variable-brightness text from the background are described. Diverse methods of detaching the foreground from the background, the so-called picture segmentation, are used. Moreover, the outcomes of different methods are compared.
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Traffic lanes and interruptions detection
Dojava, Marian ; Červinka, Luděk (referee) ; Horák, Karel (advisor)
This master´s thesis deals with depiction aplication of camera like sensitive element for assisting system of car. It was proposed, how find a road, a lane and a obstacle on roadways. Only one camera was aplication for it. Solution is realized by methods, that are based on color and gradient of image. It applies simple methods and methods with mathematical model. Result is sum of method and its test and comparing. Realization of my program is present at resume of this thesis.
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Implementation of Algorithm for Recognition of Eye Retina
Ondroušek, Jan ; Stružka, Jaroslav (referee) ; Hájek, Josef (advisor)
Vessel structure is a very important element in medical sience for diagnosis of eye and cardiovascular diseases. Therefore, its automatic segmentation is very important too. In introduction there is a short description of eye retina. After that, method of implementation is presented according to Ing. Jan Odstrčilík's thesis - Analyze of colour retinal images aimed to segmentation of vessel structures created under the auspices of Brno University of Technology - Faculty of Electrical Engineering and Communication, Department of Biomedical Engineering in 2008. This method is based on filtering input image with properly designed filtering masks, followed by thresholding with properly calculated value and finally cleaning result image from artefacts. Algorithm was written in C++ language. All important functions were implemented for purpose of given method with consideration on speed and accuray. Main sections of source code with description of user interface are introduced next in this thesis. At the end, the implementation was tested on real images from ÚBMI and DRIVE databases, results were recorded, expansions and adjustments possibilities of implementation were debated.
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