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Advanced objective measurement criteria applied to image compression
Šimek, Josef ; Průša, Zdeněk (referee) ; Malý, Jan (advisor)
This diploma thesis deals with the problem of using an objective quality assessment methods in image data compression. Lossy compression always introduces some kind of distortion into the processed data causing degradation in the quality of the image. The intensity of this distortion can be measured using subjective or objective methods. To be able to optimize compression algorithms the objective criteria are used. In this work the SSIM index as a useful tool for describing the quality of compressed images has been presented. Lossy compression scheme is realized using the wavelet transform and SPIHT algorithm. The modification of this algorithm using partitioning of the wavelet coefficients into the separate tree-preserving blocks followed by independent coding, which is especially suitable for parallel processing, was implemented. For the given compression ratio the traditional problem is being solved – how to allocate available bits among the spatial blocks to achieve the highest possible image quality. The possible approaches to achieve this solution were discussed. As a result, some methods for bit allocation based on MSSIM index were proposed. To test the effectivity of these methods the MATLAB environment was used.
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Enhancement of bio-medical image signals
Gregor, Michal ; Šmirg, Ondřej (referee) ; Přinosil, Jiří (advisor)
When scanning biomedical images by magnetic resonance or ultrasound, unwanted elements in the form of noise are entered to the image. With help of various methods it is possible the noise from the image partially remove. There are many methods for noise reduction and every one works on a different principle. As a result of this the results of these methods are different and is necessary for them to be objectively assessed. There is use for the adjustment of the images wavelet transformation and some treshold techniques in the work. The quality of the resulting pictures is tested by the methods for objective quallity tests. Testing was done in the MATLAB program environment on the pictures from magnetic resonance and pictures from ultrasound.
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Modern Methods of MR Static Image Enhancement
Zbranek, Lukáš ; Přinosil, Jiří (referee) ; Smékal, Zdeněk (advisor)
The aim of this masters thesis is design and implement an appropriate method for highlighting MR images and the identification of rough edges to provide for division of controlled areas. To this purpose is possible to use the Wavelet analysis. For the simulation environment I using MATLAB entviroment, where introduce the comparison for different types of de-noising and too for different mother wavelets. These methods will be implemented on various MR images of termoromandibular joint.
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Wavelet transform based object detector
Mikuš, Ondřej ; Průša, Zdeněk (referee) ; Rajmic, Pavel (advisor)
This thesis deals with applying methods on object detection in image. Separation of objects off the background is often needed during the image processing. It isolates the region of interest that can be worked with. The main purpose of this paper is the explanation of principles of pre-processing and segmentation of image, resulting in object detection using the wavelet transformation. This wavelet transformation is described more in detail, because it is the base of the primary used method. In the practical part of this thesis the main method was implemented to MATLAB environment and tested on set of images. The method was tested for robustness against noise and blur of image. It was compared with commonly used methods, using the edge detectors and thresholding. A simulation program was created for comparison of methods efficiency, including user interface.
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Modulation technique design for radio channels with interference
Bělohlávek, Jiří ; Kubánková, Anna (referee) ; Pust, Radim (advisor)
This thesis concisely describes essential type of modulation technique for transmission of binary signal. In introductory part there are summarized advantages and disadvantages for each described modulation technique. There are described proceeding of modulation and demodulation too. Next part is specialized mainly to determination of incorrect receiving probability. For each modulation technique are calculated theoretical values of bit error rate and compiled graph. In practical part there are described possibilities of Matlab platform for measurement of bit error rate. In implement Simulink there is built model of communication channel with additional AWGN channel. Graphs are constructed from simulation data by the help of model’s control script. On selected modulation technique are inspected various elements which are reacted with graph. In finale part there are compared theoretical and measured values and summarized analysis.
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Optimization of Active Network Element Control
Přecechtěl, Roman ; Kacálek, Jan (referee) ; Škorpil, Vladislav (advisor)
The thesis deals with the use of neuronal networks for the control of telecommunication network elements. The aim of the thesis is to create a simulation model of network element with switching array with memory, in which the optimization kontrol switching array is solved by means of the neural network. All source code is created in integrated environment MATLAB. To training are used feed-forward backpropagation network. Miss achieve satisfactory result mistakes. Work apposite decision procedure given to problem and it is possible on ni tie up in an effort to find optimum solving.
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Conversion of monophonic melody from the audio signal into the MIDI protocol stream
Krupička, Jan ; Rášo, Ondřej (referee) ; Mačák, Jaromír (advisor)
The aim of this thesis is to compare possibilities of the pitch extraction methods in the monophonic melody. There is presented the overview of the methods based on the speech pitch extraction techniques in the thesis. These methods uses frequency, time and „cepstral“ domain. They are compared in the term of success of the detection of various test signals. The part of the thesis specification is the implementation of these methods in Matlab. There are described basics of sound features at the beginning of this work. The overview of the musical tuning systems is mentioned and there is described a problem of the determination of the pitch from the detected frequency. There is considered an issue of MIDI protocol in the next part of the work. There are described the brief history and the essential structure of MIDI protocol. The last task of the work was the creation of the program in C language. The purpose of the program is to analyze the monophonic melody in audio signal form and assign note numbers to the detected sounds according to MIDI specification. After that the numbers are written into the standard MIDI file (SMF). There was implemented a correlation pitch detection algorithm in this program. It had the best results as compared to the others. There was used the fast correlation based on Fast Fourier transformation to accelerate computing of the correlation. The program was created in the form of MEX function, which provides various possibilities to be used in Matlab. There was also attached the description of the FFTW library, which was used to compute FFT.
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Computer analysis of sport matches
Židlík, Pavel ; Balík, Miroslav (referee) ; Atassi, Hicham (advisor)
This work deals with the possibility of a fast football match analysis from audio part of record with the possibility of implementation of some methods for other than football matches as well. The first intention was concentrated on detection of whiz of the soccer whistle that has specific frequency in its specter, which is out of common speech frequency. After detection harmonic frequency , the attention was focused on the definition of whiz meaning. Referee was helpful with the issue as he informed me about the number of whiz styles and provided me with referential samples for whiz classification. Neural network with back propagation was used for definition of whiz meaning. Another subject for detection of important moments of the match was concentration on the commentator’s basic tone. In case the commentator is really excited with the match, his basic speech tone automatically intensifies with every important action of the game. Analysis of commentator’s intensified basic speech tone was realized in this work too. Also the national hymns of teams playing against each other are a significant moment of the match. That is why detection of a hymn became another subject of analysis. Advantages of MFCC were used to obtain audio signal feature, from which 20 coefficients were gained. These were used as an entrance for classifier based on neural network with back propagation. For easy usage of these methods a graphic user interface with possibility of well-arranged look on gained results and also with possibility of replaying chosen section was created.
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Toolbox for the cooperation of MATLAB and external simulation programs
Moravec, Petr ; Sekanina, Lukáš (referee) ; Oliva, Lukáš (advisor)
In this Master's thesis scripting interface of two programs CST Microwave studio and Ansoft HFSS for the purpose of analysis of electromagnetic structures is described. The work is focuses control of these programs with help of scripting languages and system's interface of MS Windows XP. Next the process of connecting programs with MATLAB is shown on commented scripts together with an example of complete analysis of a chosen problem, and the import and export of results results in MATLAB. Further the functions which form programming interface between MATLAB and simulation programs are designed and implemented. The interconnection layer makes the complete control of simulating programs possible using the function description published in the official documentation of used simulation programs. The layer is described in reference manual in detail and it is used for optimization with use of Particle swarm optimalization (PSO) of planar antenna model. Then there is presented another usage of the layer for an implementation of global optimization methods - SOMA and DE including suggestion of process for comparison efficiency of optimization algorithms on simple electromagnetic models.
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Automotive antenna for mobile communications
Porč, Jan ; Láčík, Jaroslav (referee) ; Pokorný, Michal (advisor)
This thesis deals with design of flush–mounted planar disc antenna suitable for use in vehicles. For each of the bands GSM900 and GSM1800, which are used in Czech republic, an independent antenna has been created. As a simulator of the electromagnetic field the program IE3D has been used. For the improvement of theoretical results an optimisation in the program MATLAB has been developed. As the optimisation method the genetic algorithms have been selected.
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