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DICOM protocol analysis and its utilisation in image signal processing
Valouch, Lukáš ; Přinosil, Jiří (referee) ; Šmirg, Ondřej (advisor)
This Bachelor thesis describes DICOM which is a summary of standards for handling, storing and transmitting information in medical imaging. This standard is developed by organizations ACR and NEMA, it is very large file and it contains 18 of documents which are an actual version of this norm. The last norm was got out in 2008. The most important part of this format of date and files is data image processing so called off-line communication. It follows description of implemented application in C, C++ languages by the help of Imebra library. This Imebra library is free in terms of license of GNU GPL. The resultant program is standard of DICOM from, which is described above. This program is concerned with imaging of 16 bits of dept on 8 bits of dept of display devices, for example common computer displays. This application is able to display several layers of DICOM’s pictures. Each of layers contains separated bites which are presented by importance of levels.
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Detection of security aids in image signal
Burdík, Vojtěch ; Šmirg, Ondřej (referee) ; Přinosil, Jiří (advisor)
This work is devoted to the relatively new field of computer – computer vision. It focuses on the recognition of people, positioning and colour detection of clothing placed on person. The aim is to build an algorithm that would be able to locate the person in the picture and would make colours tests of clothing and helmets. For image processing were used OpenCV library functions and from algorithms was compiled program solving this problem. The output of the program is the answer, what colour is person at stated locations wearing, and if clothing and helmet are the same colour, the person is evaluated as properly dressed. The resulting program is then disassembled and parts of the code are in detail described in this work. There is explained how to use correctly each OpenCV function used in program.
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Protecting of image data
Nováček, Aleš ; Přinosil, Jiří (referee) ; Číka, Petr (advisor)
Bachelor´s thesis is about protection of digital images, especially about modern watermarking techniques. It consists of three main parts. The first one is the theoretical part, that describes watermarking terminology, techniques of embeding and detection of watermark, watermarking applications and watermarking requirements such as robustness and impercebility. The second and third part compares two methods of watermarking. Both methods are based on the transformation of image to the frequency domain. The first method uses discrete cosine transformation and the second one discrete wavelet transformation. Method using DCT embeds watermark by swaping DCT coefficients. The second method embeds watermark by modifying some coefficients of DWT decomposition according to the equation vi´= vi (1+sxi ), where vi´ is a coefficient of watermarked image, vi is a coefficient of original image, xi is pixel of watermark and s is scale factor, constant, that affects robustness of watermark.
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Advanced QR-Code reader for Android
Kubík, Martin ; Přinosil, Jiří (referee) ; Šmirg, Ondřej (advisor)
The aim of this diploma thesis was to created application for detection and decoding QR codes using devices with the Android Operating System. For preprocessing of the visual field camera is used OpenCV library. Designed preprocessing string searches a perspective transforms possible QR codes. This is suppressed a shape distortion QR code that would otherwise reduce the successful decoding. At the same time the preprocessing string applied unsharp mask, which reduces the effect of motion blur image caused by the camera motion. Thus preprocessing scene is finally decoded using ZXing library. Described manner it is possible to achieve a higher success rate detection and decoding of QR codes than other conventional QR readers.
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Image similarity based on colour
Hampl, Filip ; Přinosil, Jiří (referee) ; Uher, Václav (advisor)
This diploma thesis deals with image similarity based on colour. There are discussed necessary theoretical basis for better understanding of this topic. These basis are color models, that are implemented in work, principle of creating the histogram and its comparing. Next chapter deals with summary of recent progress in the field of image comparison and overview of several most used methods. Practical part introduces training image database, which gives results of success for each created method. These methods are separately described, including their principles and achieved results. In the very end of this work, user interface is described. This interface provides a transparent presentation of the results for the chosen method.
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Height Measurement in Digital Image
Olejár, Adam ; Přinosil, Jiří (referee) ; Říha, Kamil (advisor)
The aim of this paper is a summary of the theory necessary for a modification, detection of person and the height calculation of the detected person in the image. These information were then used for implementation of the algoritm. The first half reveals teoretical problems and solutions. Shows the basic methods of image preprocessing and discusses the basic concepts of plane and projective geometry and transformations. Then describes the distortion, that brings into the picture imperfections of optical systems of cameras and the possibilities of removing them. Explains HOG algorithm and the actual method of calculating height of person detected in the image. The second half describes algoritm structure and statistical evaluation.
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Non-linear character of optical environment
Žáček, Martin ; Míča, Ivan (referee) ; Přinosil, Jiří (advisor)
This paper describes theoretical and application options of nonlinear effects in optical medium. Optical medium means fiber optics, because the fiber is the most employed optical medium at these days. Basic statements of this work are theoretical information with mathematical and physical expressions. These expressions defines nonlinear medium and effects which are founded here. These effects are split to second and third orders. Nonlinear effects of second orders are Second-harmonic Generation, Three-wave Mixing process. Nonlinear effects third orders are Third-harmonic Generation, Self-phase Modulation, Cross-phase Modulation, Four-wave Mixing and Degenerative Four-wave Mixing process. These effects are extended by scattering effects – Brillouin’s and Raman‘s Scattering. The next point discuss about optical communication system DWDM. DWDM uses dense wavelength multiplexing. Nonlinear effects have a few negative influences on these systems. There are requests for high bandwidth and communication speed. FWM and XPM limit these requests. They can invoke cross-talks. We support theoretical information with application examples and simulations at the end of this work. We use OptSim v.4.0 program. We are simulate FWM and XPM effect in depend on chromatical dispersion and power.
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Face recognition in digital images
Hauser, Václav ; Přinosil, Jiří (referee) ; Říha, Kamil (advisor)
This master thesis deals with the detection and recognition of faces in the image. The content of this thesis is a description of methods that are used for the face detection and recognition. Method described in detail is the principal component analysis (PCA). This method is subsequently used in the implementation of face recognition in video sequence. In conjunction with the implementation work describes the OpenCV library package, which was used for implementation, specifically the C ++ API. Finally described application tests were done on two different video sequences.
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Speaker Segmentation using statistical methods of classification
Adamský, Aleš ; Přinosil, Jiří (referee) ; Smékal, Zdeněk (advisor)
The thesis discusses in detail some concepts of speech and prosody that can contribute to build a speech corpus for the speaker segmentation purpose. Moreover, the Elan multimedia annotator used for labeling is described. The theoretical part highlights some frequently used speech features such as MFCC, PLP and LPC and deals with currently most popular speech segmentation methods. Some classification algorithms are also mentioned. The practical part describes implementation of Bayesian information criterium algorithm in system for automatic speaker segmentation. For classification of speaker change point in speech, were used different speech features. The results of tests were evaluated by the graphic method of receiver operating characteristic (ROC) and his quantitative indices. As the best speech features for this system were provided MFCC and HFCC.
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