|
|
GrooveSpired - Application for Drums Training
Štrba, Tomáš ; Beran, Vítězslav (referee) ; Szőke, Igor (advisor)
The main goal of this work is to design and to implement a mobile application for drums training. The application must be capable of displaying drum notation of different grooves from various music styles, playing audio examples of those grooves and also analyze and evaluate drumming skills of drummers. The main method for audio processing is discrete wavelet transform. Results show true value rate above 96%.
|
|
|
Wavelet transform
Valter, Boris ; Hlávka, Zdeněk (advisor) ; Dvořák, Jiří (referee)
Wavelet transform is a term from signal analysis. It is mostly used in physics, but also in finance, where we can use it to find a trend in different financial data. In the first chapter we will describe two older methods of signal analysis: Fourier transform and short-time Fourier transform. In the second chapter we show, how wavelet transform works, derive frequently used algorithm for calculating discrete wavelet transform and at the end we show several practical examples. This thesis was considered to deepen the knowledge of time-frequency analysis of signals, for better understanding of the principle, how wavelet transform works, and for potential extending its use. Powered by TCPDF (www.tcpdf.org)
|
|
|
Lifting Scheme Cores for Wavelet Transform
Bařina, David ; Kälviäinen, Heikki (referee) ; Sojka, Eduard (referee) ; Zemčík, Pavel (advisor)
Práce se zaměřuje na efektivní výpočet dvourozměrné diskrétní vlnkové transformace. Současné metody jsou v práci rozšířeny v několika směrech a to tak, aby spočetly tuto transformaci v jediném průchodu, a to případně víceúrovňově, použitím kompaktního jádra. Tohle jádro dále může být vhodně přeorganizováno za účelem minimalizace užití některých prostředků. Představený přístup krásně zapadá do běžně používaných rozšíření SIMD, využívá hierarchii cache pamětí moderních procesorů a je vhodný k paralelnímu výpočtu. Prezentovaný přístup je nakonec začleněn do kompresního řetězce formátu JPEG 2000, ve kterém se ukázal být zásadně rychlejší než široce používané implementace.
|
|
|
Effect of Noise on Video Compression
Anton, Matyáš ; Drábek, Vladimír (referee) ; Bařina, David (advisor)
Videos are in fact image signals and as such, they are susceptible to distortions in the form of noise. This thesis' goal was to determine how the presence of noise can affect the results of image data compression as well as what impact might the lossy compression have on the noise present. Four contemporary compression formats were chosen, namely H.264, H.265, Motion JPEG 2000 and DIRAC, representing different approaches to the video compression, especially the contrast between a discrete cosine transform and a discrete wavelet transform.
|
|
|
ECG Signal Wavelet Filtering
Zahradník, Radek ; Kozumplík, Jiří (referee) ; Smital, Lukáš (advisor)
The aim of this work is introduction to problems about the wavelet transform and then to use this transformation to filter ECG signal disturbed with myopotentials. The first part of this thesis contains basic information about the measurement, waveform and disturbance of ECG signal. The next part describes the method of wavelet transform and its use for the signal filtering The last part describes the practical part of work, where the results of filtering with different filter settings are evaluated, especially the various types of thresholding. At the end of this part is a comparison of results from wavelet and linear filter.
|
|
|
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.
|
|
|
Image Compression Using the Wavelet Transform
Kaše, David ; Klíma, Ondřej (referee) ; Bařina, David (advisor)
This thesis deals with image compression using wavelet, contourlet and shearlet transformation. It starts with quick look at image compression problem a quality measurement. Next are presented basic concepts of wavelets, multiresolution analysis and scaling function and detailed look at each transform. Representatives of algorithms for coeficients coding are EZW, SPIHT and marginally EBCOT. In second part is described design and implementation of constructed library. Last part compare result of transforms with format JPEG 2000. Comparison resulted in determining type of image in which implemented contourlet and shearlet transform were more effective than wavelet. Format JPEG 2000 was not exceeded.
|
|
|
Wavelet Filtering of ECG Signals
Staša, Josef ; Kolář, Radim (referee) ; Kozumplík, Jiří (advisor)
The aim of this project is introduction to problems about filtering of signals using wavelet transform. This method is very effective and in present it is often exploited. The main imposition is to use wavelet transform for filtering of ECG signals. Practical part of my project is realized wiener filtering based on DTWT in MATLAB software, to show advantages, disadvantages and compare linear filtering .
|
|
|
Segmentwise Discrete Wavelet Transform
Průša, Zdeněk ; Vargic,, Radoslav (referee) ; Dr. Peter L. Sndergaard (referee) ; Rajmic, Pavel (advisor)
Dizertační práce se zabývá algoritmy SegDWT pro segmentový výpočet Diskrétní Waveletové Transformace – DWT jedno i vícedimenzionálních dat. Segmentovým výpočtem se rozumí způsob výpočtu waveletové analýzy a syntézy po nezávislých segmentech (blocích) s určitým překryvem tak, že nevznikají blokové artefakty. Analyzující část algoritmu pracuje na principu odstranění přesahu a produkuje vždy část waveletových koeficientů z waveletové transformace celého signálu, které mohou být následně libovolně zpracovány a podrobeny zpětné transformaci. Rekonstruované segmenty jsou pak skládány podle principu přičtení přesahu. Algoritmus SegDWT, ze kterého tato práce vychází, není v současné podobně přímo použitelný pro vícerozměrné signály. Tato práce obsahuje několik jeho modifikací a následné zobecnění pro vícerozměrné signály pomocí principu separability. Kromě toho je v práci představen algoritmus SegLWT, který myšlenku SegDWT přenáší na výpočet waveletové transformace pomocí nekauzálních struktur filtrů typu lifting.
|
|
|
The Noise Spectroscopy of Radiation Detectors Based on the CdTe
Zajaček, Jiří ; Štourač, Ladislav (referee) ; Hájek, Karel (referee) ; Grmela, Lubomír (advisor)
The main object of this work is noise spectroscopy of CdTe radiation detectors (-rays and X–rays) and CdTe samples. The study of stochastic phenomenon and tracing redundant low-frequency noise in semiconductor materials require long-term measurements in time domain and evaluate suitable power spectral densities (PSD) with logarithmic divided frequency axes. We have used the means of time-frequency analysis derived from the discrete wavelet transform (DWT) and we have designed the effective algorithm for PSD estimation, which is comparable with an original analog method. CdTe single crystal with Au contacts we can imagine as a series connection of two Schottky diodes with a resistor between them. The bulk resistance at constant temperature and other constant parameters changes due to the carrier concentration changing only. The p-type CdTe sample shows metal behavior with every temperature changes. Semiconductor properties of the sample begin to dominate just after some period of time. This behavior is caused by the hole mobility changing. The voltage noise spectral density of 1/f noise depends on the quantity of free carriers in the sample. All the studied samples have very high value of low frequency noise, much higher than it should have been according to Hooge’s formula. The excess value of low frequency noise is caused by the low carrier concentration within the depleted region.
|
guest ::
