|
|
Audio inpainting algorithms
Kolbábková, Anežka ; Veselý, Vítězslav (referee) ; Rajmic, Pavel (advisor)
Tato práce se zabývá doplňováním chybějících dat do audio signálů a algoritmy řešícími problém založenými na řídké reprezentaci audio signálu. Práce se zaměřuje na některé algoritmy, které řeší doplňování chybějících dat do audio signálů pomocí řídké reprezentace signálů. Součástí práce je také návrh algoritmu, který používá řídkou reprezentaci signálu a také nízkou hodnost signálu ve spektrogramu audio signálu. Dále práce uvádí implementaci tohoto algoritmu v programu Matlab a jeho vyhodnocení.
|
|
|
Interactive applets supporting teaching digital image processing
Křivánek, Jiří ; Mangová, Marie (referee) ; Rajmic, Pavel (advisor)
This thesis deals with the creation of applications for support of education computer graphics. The aim is to create a simple application which will show the functioning of the various methods. I implemented convolution methods for image filtering, dithering engaged in the distribution errors, bit planes that show each bit plane image, gamma correction to lighten or darken the image and procedural textures. All these methods are created in the form of Java applets.
|
|
|
Compressed sensing in magnetic resonance perfusion imaging.
Mangová, Marie ; Veselý, Vítězslav (referee) ; Rajmic, Pavel (advisor)
Magnetic resonance perfusion imaging is a today's very promising method for medicine diagnosis. This thesis deals with a sparse representation of signals, low-rank matrix recovery and compressed sensing, which allows overcoming present physical limitations of magnetic resonance perfusion imaging. Several models for reconstruction of measured perfusion data is introduced and numerical methods for their software implementation, which is an important part of the thesis, is mentioned. Proposed models are verified on simulated and real perfusion data from magnetic resonance.
|
|
|
Image watermarking in frequency domain
Štrbíková, Tatiana ; Rajmic, Pavel (referee) ; Číka, Petr (advisor)
This thesis analyze digital watermarking. At first we can read about watermarking in generally. Secondarily, it considers about possibilities of watermarking, therefore about different ways of watermarking. Methods of digital watermarking we can divide into three main categories: spatial domain watermarking, frequency domain watermarking and spread spectrum watermarking. In detail there is described frequency domain watermarking. Two methods are compared. First method, which use DCT (Discrete cosine transformation) and second metohd, which use DWT (Discrete wavelet transformation). Finally we can found out, which method seems to be better.
|
|
| |
|
| |
|
|
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.
|
|
|
Modern restoration of audio containing missing portions
Skyva, Pavel ; Mangová, Marie (referee) ; Rajmic, Pavel (advisor)
This bachelor thesis deals with modern method of audio signal restoration. The reconstruction is primarily based on sparse signal representations. In thesis is described the way of searching sparse coefficients using proximal Douglas-Rachford algorithm and following computation of reconstructed signal using this coefficients. The algorithm of reconstruction is implemented in the MATLAB software with toolbox LTFAT included. Results of the reconstruction are compared using objective evaluation method Signal-to-Noise ratio (SNR).
|
|
|
Methods for increasing bit-depth in images
Záviška, Pavel ; Koldovský, Zbyněk (referee) ; Rajmic, Pavel (advisor)
The goal of this bachelor thesis is the application of an issue of sparse representations on the task of increasing bit-depth in images. Standard methods for bit-depth expansion are described, subsequently a method using sparse representation of an image signal is introduced. Methods are programmed in the Matlab enviroment. The results of the methods implemented are compared by using PSNR, SSIM objective indexes and subjectively using an online questionnaire.
|
|
|
Methods of image dithering
Pelc, Lukáš ; Křupka, Aleš (referee) ; Rajmic, Pavel (advisor)
Master’s thesis discusses methods for dithering image. The basis is the explanation of the theory of digital images, color models, color depth and color range. Followed by the dismantling of the basic dithering methods which are a thresholding method, a random and matrix diffusion. Discussed are advanced methods of dithering with error distribution, bee with best known method Floyd-Steinberg. Included is a comparison of different methods including subjective comparison using a questionnaire. Program part is JAVA applet that shows the possibility of generating images using various dithering methods.
|
guest ::
