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The use of EEG in assessing the emotional state of a person
Strakoš, Libor ; Mézl, Martin (referee) ; Potočňák, Tomáš (advisor)
This thesis is focused on EEG processing and emotion classification within two-dimensional emotion space. First part consists of theoretical research about emotional responses of human subjects on sound, image and video stimuli. Emotions are examined from aspect of physiology and psychology. Furthermore technical overview of measurement, analysis and emotion classification within two-dimensional emotional space is discussed. Based on gathered knowledge measurement setup with audiovisual stimuli was designed and measured with two independent instruments – EGI GES400MR in laboratory conditions and Emotiv EPOC device in non-laboratory conditions. Signals were processed and emotions were classified based on chosen features. Performance of classifiers in multiple feature selection setups was evaluated.
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Videocodec - Videosequence Compression
Bařina, David ; Motlíček, Petr (referee) ; Smrž, Pavel (advisor)
This thesis deals with modern methods of a lossy still image and video compression. Wavelet transformation and SPIHT algorithm also belong to these methods. In second half of this thesis, a videocodec is implemented based on acquired knowledge. This codec uses Daubechies wavelets to analyse an image. Afterwards there is a modified SPIHT algorithm applied on gained coefficients. A lot of effort was put in order to optimize this computation. It is possible to use the created codec in Video for Windows, DirectShow and FFmpeg multimedia frameworks. At the end of this thesis, commonly used codecs are compared with newly created one.
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Applications of wavelet transform in Mathematica and Sage
Novotný, Radek ; Trzos, Michal (referee) ; Rajmic, Pavel (advisor)
This thesis focuses on image processing using wavelet transform. The usage of wavelet transform is analysed especially for image compression and image noise reduction purposes. The analysis describes in detail aspects and application of the following wavelet transform methods: CWT, DWT, DTWT, 2D DWT. The thesis further explains the meaning of the mother wavelet and studies certain specific kinds of wavelets, kinds of thresholding and its purposes and also touches on the JPEG2000 standard. Mathematica and Sage software packages were used to design algorithms for image compression and image noise reduction, utilising relevant wavelet transform findings. The concluding part of the thesis compares the two software packages and results obtained using different algorithms.
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Comparison of Video Codecs
Urbánek, Pavel ; Svoboda, Pavel (referee) ; Bařina, David (advisor)
This thesis is aimed at analysis of video codecs and their comparison. First part of this document provides reader with the basic information on encoding and decoding process including high level description of often used algorithms. It describes codecs and the process of standardization. Second part is focused on test specifications and codecs comparsion itself including conclusion. PSNR, SSim and BD-PSNR are key methods used for comparing codecs.
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Advanced Methods to Multimedia Data Protection
Mikulčík, Ondřej ; Zukal, Martin (referee) ; Číka, Petr (advisor)
To protect the the copyright of multimedia works have been developed watermarking techniques, that insert an invisible watermark to the original data. The aim of this thesis was to explore modern watermarking techniques, choose three of them and realize them. Also test them, evaluate their properties and possibly improve them. All methods insert a watermark into luminance component of the original image, and work with binary or black and white watermark. All techniques work in the frequency domain using discrete wavelet transform. For the implementation of methods, have been developed software named "Watermarking" that has been programmed in JAVA Version 7. The first chapter describes the types of watermarks, the general process of insertion and extraction, watermarking systems and important feature requests of embedded water- marks. In addition, qualitative methods are mentioned for their comparisons and testing. The chapter also contains a theoretical description of the used transformations and functions. In the second chapter is described the user interface of the software "Water- marking". Chapters three and four contain a theoretical description of the implemented methods and description of implementation of insertion and extraction processes of the watermark. Also there are discussed the exact procedures for testing, the sample data, and the results which are clearly displayed in the tables. The fifth chapter discusses in detail the results obtained in testing the robustness of the watermark, using the software StirMark. In the conclusion are evaluated the advantages and disadvantages of methods and quality parameters.
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Image codecs based on the wavelet transform
Kiska, Tomáš ; Říha, Kamil (referee) ; Rajmic, Pavel (advisor)
This bachelor´s thesis describes issues of wavelet compression, which is today already in common use mainly at work with digital photographs or other pictures. Using these algorithm you can copy informations and save efficiently. There are main image formats and types of compression suitable for editing pictures desribed in this thesis. So the focus is on discrete wavelet transform, which uses so-called wavelets, the Haar´s and Daubechies wavelet are the best known of all. Next chapter of this work explores colour spaces, in which can be a picture displayed. In case of coding and encoding it is model RGB and YCbCr. Not least there is mentioned term of picture decomposition. At the end, there are image codecs EZW, SPITH and EBCOT which are describe in detail.
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Image Compression Using the Wavelet Transform
Urbánek, Pavel ; Polok, Lukáš (referee) ; Bařina, David (advisor)
This thesis is focused on subject of image compression using wavelet transform. The first part of this document provides reader with information about image compression, presents well known contemporary algorithms and looks into details of wavelet compression and following encoding schemes. Both JPEG and JPEG 2000 standards are introduced. Second part of this document analyzes and describes implementation of image compression tool including inovations and optimalizations. The third part is dedicated to comparison and evaluation of achievements.
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The use of genomic signal compression for classification and identification of organisms
Sedlář, Karel ; Vítek, Martin (referee) ; Škutková, Helena (advisor)
Modern classification of organisms is performed on molecular data. These methods rely on multiple alignment of sequences of characters which make them computationally demanding. Only small parts of genomes can be compared in reasonable time. In this paper, the novel algorithm based on conversion of the whole genome sequences to cumulative phase signals is presented. Dyadic wavelet transform is used for lossy compression of signals by redundant frequency bands elimination. Signal classification is then performed as a cluster analysis using Euclidian metrics where multiple alignment is replaced by dynamic time warping.
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Lossy Image Compression
Bařina, David ; Herout, Adam (referee) ; Sumec, Stanislav (advisor)
This thesis deals with advanced methods of lossy image compression. To the midst of these methods belong the discrete cosine transform and Haar's discrete wavelet transform. Furthermore principles of color models and algorithms used in lossless data compression are explained in this text. The purpose of this thesis is the library implementation that is based on these cognizances.
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