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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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Processing of MP3 files for DSP
Římský, Adam ; Sysel, Petr (referee) ; Herman, Ivo (advisor)
This thesys is concerned with create of compressed .MP3 files and their conversion back into PCM format. I describe individual parts of these operations for their maximal understanding by reader. Next part is generally about properties of DSP, their architecture, computation possibilities and about properties of used product by Analog Devices. In last part is showed implantation of decoder in DSP architecture.
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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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Comparison of voice and audio codecs
Lúdik, Michal ; Sysel, Petr (referee) ; Míča, Ivan (advisor)
This thesis deals with description of human hearing, audio and speech codecs, description of objective measure of quality and practical comparison of codecs. Chapter about audio codecs consists of description of lossless codec FLAC and lossy codecs MP3 and Ogg Vorbis. In chapter about speech codecs is description of linear predictive coding and G.729 and OPUS codecs. Evaluation of quality consists of description of segmental signal-to- noise ratio and perceptual evaluation of quality – WSS and PESQ. Last chapter deals with description od practical part of this thesis, that is comparison of memory and time consumption of audio codecs and perceptual evaluation of speech codecs quality.
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Adaptive data compression by neural networks
Kučera, Michal ; Přinosil, Jiří (referee) ; Koula, Ivan (advisor)
Point of the work is using of neural networks for the datecompression. This brings new possibilities as by lossless as lossy compression. Draft of a few compress algorithm show the behaviour, advantages and weak points of these systems. As the solution we use knowledge of the layered perceptron Network and we try by the change of the structure and subparameters to teach such network to compress the data, according to our entry requirement. These networks have also advantages, which are meanwhile impediment to the using practically. The goal of this is to try some algorithms, look into their characteristics and posibility of the using. Then propose next posibility solutions and upgrading of these algorithms.
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Height map compression techniques
Lašan, Michal ; Kahoun, Martin (advisor) ; Křivánek, Jaroslav (referee)
The goal of this thesis is to design a suitable method for lossy compression of heightmap terrain data. This method should accept blocks of float samples of dimensions 2^n x 2^n as an input, for which it should be able to perform progressive decompression of mip-maps (lower-resolution representations). It should keep the reconstructed data within a certain maximum per-sample error bound for each mip-map level. This bound should be in the unit of meters and adjustable by the user. Given these constraints, it should be as efficient as possible. Our method is inspired by the second generation of progressive wavelet-based compression scheme modified to satisfy the~maximum-error constraint. We simplified this scheme by factoring out unnecessary computations in order to improve the efficiency. Our method can compress a 256x256 block in about 30 ms and decompress it in about 2 ms. Thanks to these attributes, the method can be used in a real-time planet renderer. It achieves the compression ratio of 37:1 on the whole Earth 90m/sample terrain dataset transformed and separated into square blocks, while respecting the maximum error of 5m. Powered by TCPDF (www.tcpdf.org)
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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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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.
|
|
|
Comparison of voice and audio codecs
Lúdik, Michal ; Sysel, Petr (referee) ; Míča, Ivan (advisor)
This thesis deals with description of human hearing, audio and speech codecs, description of objective measure of quality and practical comparison of codecs. Chapter about audio codecs consists of description of lossless codec FLAC and lossy codecs MP3 and Ogg Vorbis. In chapter about speech codecs is description of linear predictive coding and G.729 and OPUS codecs. Evaluation of quality consists of description of segmental signal-to- noise ratio and perceptual evaluation of quality – WSS and PESQ. Last chapter deals with description od practical part of this thesis, that is comparison of memory and time consumption of audio codecs and perceptual evaluation of speech codecs quality.
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Processing of MP3 files for DSP
Římský, Adam ; Sysel, Petr (referee) ; Herman, Ivo (advisor)
This thesys is concerned with create of compressed .MP3 files and their conversion back into PCM format. I describe individual parts of these operations for their maximal understanding by reader. Next part is generally about properties of DSP, their architecture, computation possibilities and about properties of used product by Analog Devices. In last part is showed implantation of decoder in DSP architecture.
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