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Cryptography protocol with public key
Fujdiak, Radek ; Rášo, Ondřej (referee) ; Mlýnek, Petr (advisor)
The Master thesis is an introduction to cryptology. The Thesis describe cryptosystems and selects one ideal cypher for low-power microcontroler. In thesis provides manual for instal development program COde Composer Studio, basic implementation of selected cryptosystem with small numbers and suggestion for implementation selected cyptosystem with big numbers.
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Software implementation of the subjective assessments of sound quality
Špeta, Marek ; Balík, Miroslav (referee) ; Rášo, Ondřej (advisor)
The focus of this diploma thesis is on methods for the subjective assessment of sound quality according to recommandations given by International Telecommunication Union ITU. The thesis is thematically divided into four parts. The first part is an interpretation of methods based on internationally accepted standards (method of small impairments, MUSHRA, general methods). The second part describes the functional blocks of application developed for this thesis in LabVIEW enviroment. Next part explains its practical application, especially its running possibilities. The last part describes a listening experiment, aim of which was to verify the application's features and to compare the results of the subjective method used in the experiment with the results of the objective method PEAQ.
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Digital signal processing in real time
Zamazal, Zdeněk ; Mačák, Jaromír (referee) ; Rášo, Ondřej (advisor)
This work deals with digital signal processing in the field of adaptive filtering. Fundamental basics of adaptive filtering are described and primary aim is to create executable laboratory examples, using adaptive filtering, in LabView programming language. These laboratory examples are intended to be used by students fo studying and during laboratory lessons. Objective is to connect the examples with external devices, such as microphone. A microphone is used as an user's speech input acquiring interface. In the thesis is depicted Wiener's filter and problem of adaptive filtering is discussed. Contemporary adaptive algorithms are described and their applications as well. Most mentioned is the LMS algorithm and it's forms. Laboratory examples use following concepts: Adaptive Echo Cancellation, Active Noise Control and System Identification. Each of these examples is solely executable (need for LabView or Run-time engine), consisting also of theory with diagrams. Examples therefore are usable even without manual.
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Real time signal processing
Nepovím, Pavel ; Rášo, Ondřej (referee) ; Mlýnek, Petr (advisor)
The aim of the master’s thesis is to acquaint the reader with Discrete Fourier Transform DFT and its introduction to spectral analysis descrete time signals. Furthermore it describes efficient computation of the DFT using the algorithm Fast Fourier Transform FFT and effects that appear in the DFT spectral analysis, the effect of the length of the DFT, the effect of the length of the segment of the analysed signal and the leakage. Next is explained the issue of the complex representation of real bandpass signals in the baseband, called the complex envelope of signals. This represenation uses the Hilbert Transform and the analytic signal. The thesis also describes the application library Real Time Toolbox of the software Matlab/Simulink, that uses the data acquition card AD622 allows to connect and process real signals in real time. In Matlab/Simulink with use this facilities is create the laboratory lesson, that simulating the complex represenation of real bandpass signals in real time.
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Objective methods for evaluation of the audio signal quality
Granát, Michal ; Rajmic, Pavel (referee) ; Rášo, Ondřej (advisor)
This diploma thesis deals with the objective methods of audio-signal qualification. In detail have been described algorithms to the reader which are used in individual methods. Individual methods are analyzed from computational intensity, ability to predict precisely subjective quality of audio-signals, point of view. There have been described basic variables by which audio-signals are described in further parts of this thesis. Second part has been dedicated to theoretical description of individual methods – their advantages and disadvantages and practical forms of usage. Third part has been dedicated to implementation of two chosen methods in graphical interface of MATLAB program. All the functions are described in detail which these applications offer. In the last part of the thesis there are in detail described results obtained by practical testing of audio-signals with different character in created applications and evaluated quality of reached results as an outcome.
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Secure access to web interface
Kazik, Milan ; Hajný, Jan (referee) ; Rášo, Ondřej (advisor)
This document contains basic principles and processes regarding secure access to web information system. It consists of theoretic and applied part. These are mainly written together in thesis’s chapters. Theoretic informations were tested on simple web application created in PHP computer language on Apache web server using MySQL database. In the beginning, there is an analysis of used programming environment, especially it’s advantages and disadvantages. The main part of this document is simple characterization of many security problems which can be found on many websites all around the world. In the first place it’s a handling problem of inputs and outputs in the web applications. Password disputableness is solving separatelly. Theory of a problem is analysed first of all. Then a couple of solving methods are suggested and the one which is practically realized is described in detail. There is a notification system created which is used to inform user about errors appeared in web application. In the last section there is a client and server certificates described. This document contains fully characterization of used scripts and connection between them. They are supplemented with many pictures and screenshots which are used to better understanding the disputableness of web security.
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IMS security solutions
Porubský, Tomáš ; Rášo, Ondřej (referee) ; Mácha, Tomáš (advisor)
In the first part of my master's thesis the network architecture of IMS (IP Multimedia Subsystem) is presented. The database of subscribers HSS (Home Subscriber Server) and SLF (Subscription Locator Function), as well as a SIP CSCF servers (Call Session Control Functions) process a SIP signalization and an AS application server performing services, etc. I focus on the registration of subscribers in the IMS network with a list of transmitted messages and description of each interface that is used in this network. The most important interfaces, which I described here, are Gm, Mw, Cx, Dx and Sh. Then I focused on security in IMS problems, which are divided into categories of access security and network security. After that is the implementation of IMS network in an open source Open IMS Core System considered under the Linux operating system. Here is the problem description from the actual system installation, through the configuration of all necessary elements of the network to the communication party itself. The communication analysis in the initial registration process and in subsequent communications is described. Finally I created laboratory exercises with a focus on the Open IMS Core System, where students learn about architecture and principle of networks based on IMS technology operation, with individual elements necessary for the operation of the network and their configuration. Students also test simple captured traffic analysis.
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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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Programming of processors in 32- or 64-bit operation systems
Rášo, Ondřej ; Kyselý, František (referee) ; Balík, Miroslav (advisor)
Main topic of this thesis is Win32 application programming interface and symbolic instructions programming language. It can be divided into four parts. First part sums the basics of 32-bit programming in symbolic instructions language in Windows. Second part describes the Win32 resources for computer intercommunication. Third part presents, describes and comments selected problems in symbolic instructions language.Last part covers a creation of an example application. This application and its parts will be the content of computer exercises in VUT Brno FEEC subject Počítače a jejich periferie.
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