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Performance analysis of the newest video encoding standards
Klejmová, Eva ; Polák, Ladislav (referee) ; Slanina, Martin (advisor)
The aim of this work is to describe state-of-the-art high-definition video compression algorithms. The thesis focuses on the differences between algorithms and their functionality. Procedures for video sequences compression based on reference implementations of selected codecs are being proposed and their important parameters are being discussed. Bachelor's thesis deals with comparison of reference implementations based on subjective and objective video quality measurements and time requirements. The graphic interface for selected codecs has been also designed.
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Class D 2.1 audio amplifier for laboratory measurements
Děcká, Klára ; Polák, Ladislav (referee) ; Kratochvíl, Tomáš (advisor)
This semestral thesis deals with a draft and construction of the design of an class D audio amplifier with pulse width modulation. The resulting design consists of a supply protection, an active crossover and the output power stage itself. The amplifier is made in 2.1 configuration, the amplifier for mid/high audio frequency drives 2 × 30 W output into a 8 load, subwoofer drives 1 × 100 W into a 2 load. The control centre of the whole application is an integrated circuit TPA3116D2 by Texas Instruments company. The resulting audio amplifier will be used as a device for laboratory measurements.
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Rotational 3D scanner
Švehla, Ľubomír ; Polák, Ladislav (referee) ; Kaller, Ondřej (advisor)
The point of this project is to design and construct a rotational 3D scanner. It is both about the hardware and software part. Low construction price is important factor in the hardware part and therefore the hardware part is really simple. Software part is solved by the FFmpeg tool and programming environment MATLAB. From the selected number of frames from the synchronized video the irradiated part is segmented. Consequently by compositing these traces a 3D model is gained. To gain a better result, the program uses two cameras. Program can be fully controlled from GUI.
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Measurement of quality and errors of digital video in MPEG-2 TS at DVB-T reception
Kadlček, Jiří ; Kratochvíl, Tomáš (referee) ; Polák, Ladislav (advisor)
This bachelor’s thesis describes structure of the transport stream MPEG-2 TS of the DVB-T standard and subjective and objective measuring methods of the video quality. The work also includes the description of the measurement devices and software Quality Analyzer R&S DVQ, measuring decoder ¸ DVMD, MPEG-2 Realtime Monitor, MPEG-2 Quality Monitor, which were used for the measuring the video quality and errors of the MPEG-2 TS in DVB-T. In the next part the work deals with the measurement and analysis of errors and quality of digital video stream in MPEG-2 TS. The obtained results from the measurement are presented in tables and graphically evaluated. In this work a twentyfour hour measurements of errors and quality of digital video stream in MPEG-2 TS were made. The obtained results from these measurements are evaluated and discussed. Finally, a new laboratoy work for the simultaneously measurement of the errors in video stream and video quality of the MPEG-2 TS stream was proposed.
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Quality measurement of analog and digital terrestrial television broadcasting
Zach, Ondřej ; Polák, Ladislav (referee) ; Slanina, Martin (advisor)
This bachelor‘s thesis deals with the description of basic features of the analog and digital television broadcasting and suggestion of a method for objective video quality evaluation at both broadcasting types. The base of this thesis is description of picture broadcast technology in analog and digital form. Also principles of some video quality evaluation metrics are described. In this thesis, a method for video quality comparison is suggested, including a verifying of this method. According to this method, sequences at changing broadcasting conditions were recorded for both broadcasting types. The quality factors of these sequences were computed and on the basis of these factors, the analog and digital TV broadcasting were compared.
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Video stream objective quality evaluation in MATLAB
Noghe, Petr ; Slanina, Martin (referee) ; Polák, Ladislav (advisor)
This work deals with the picture and video objective quality evaluation in MATLAB. The first part of this work describes the methods of the assessment of picture and video quality. The second part focused on the introduction of the source image coding. For the objective image and video quality evaluation an appropriate application in MATLAB was created. For the testing of the created application a several pictures and videos with different properties were used. Finally, obtained results are evaluated and discussed.
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Analysis and Simulation of the Signals Transmission in the DVB-H/SH Standards
Polák, Ladislav ; Rupp, Markus (referee) ; Grgic, Songa (referee) ; Kratochvíl, Tomáš (advisor)
Tato disertační práce se zabývá analýzou, simulací a měřením zpracování a přenosu signálů digitální televize pro příjem mobilního TV vysílání ve standardech DVB-H a DVB-SH. Tyto standardy vycházejí z předpokladu, že příjem signálu je charakterizován modely přenosových kanálů s vícecestným šířením. Tyto, tzv. únikové kanály, jsou charakterizovány hlavně zpožděním a ziskem jednotlivých cest. V závislosti na dalších parametrech (rychlost přijímače, Dopplerovské spektrum), je možné rozdělit únikové kanály do třech hlavních skupin: mobilní, přenosné a fixní. Dá se předpokládat, že v různých modelech kanálů bude přenášený signál různě ovlivněn. Proto je potřebné najít optimální parametry systémů (DVB-H/SH) pro kvalitní příjem vysílaných služeb mobilní televize, což je hlavním cílem této disertační práci. Pro tento účel byly vytvořeny dvě vhodné aplikace (jedna pro DVB-H a jedna pro DVB-SH) s GUI v prostředí MATLAB, které umožňují simulovat a analyzovat míru zkreslení signálu v případě mobilních, přenosných a fixních scénářů přenosu. Navíc, tyto aplikace obsahují i druhý samostatný simulátor pro nastavení a modifikaci parametrů jednotlivých přenosových cest. Díky tomu je možné zhodnotit vliv parametrů celého systému a kanálových modelů na dosaženou chybovost (BER a MER) a kvalitu přenosu. Ve všech přenosových scénářích (v závislosti na poměru C/N) byly získané, vyhodnocené a diskutované zkreslení signálů. Navíc, u standardu DVB-H, všechny získané výsledky ze simulací byly ověřeny měřením. Rozdíly mezi dosaženými výsledky (simulace a měření) byly rovněž podrobeny diskuzi. Tuto disertační práci je možné rozdělit do čtyř hlavních částí. První část disertační práce se zabývá rešerší současného vývoje v oblasti digitálního televizního vysílání na mobilní terminály ve standardech DVB-H/SH. Na konci této části jsou jasně popsány cíle této disertační práce. Druhá část práce je zaměřená na stručný popis blokového diagramu vysílačů v obou standardech DVB-H/SH. Dále jsou stručně popsány modely přenosových kanálů, které se používají pro modelování přenosu signálu. Stručný popis vytvořených aplikací, i s vývojovým diagramem, které jsou vhodné pro simulaci a analýzu přenosu v DVB-H/SH, jsou popsány v třetí části práce. Čtvrtá a nejdelší část této disertační práce se zabývá vyhodnocením získaných výsledků ze simulací a měření.
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Comparison of compression algorithms for high definition video
Dvořák, Martin ; Polák, Ladislav (referee) ; Slanina, Martin (advisor)
Bachelor's thesis deals with comparison and analysis of various instruments of the present-day compression algorithms used to compress high-definition video. Video sequences require a large amount of memory for their storage and take up bandwidth for their transmission, so it is necessary to compress video signals with regard to the quality of video after decompressing. The work focuses mainly on the differences between the algorithms and overall performance. Part of this work is a compressed video database, comparing the performance of different algorithms and the subjective quality of compressed video.
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Simulation of the DVB-C and DVB-C2 transmission and their comparison
Cibulka, Tomáš ; Hüttl, Ondřej (referee) ; Polák, Ladislav (advisor)
This Master thesis deals with description, analysis and simulation of standards of digital video broadcasting DVB-C and DVB-C2. There is described mainly the transmission system, channel coding, type of modulation and OFDM symbols generation. Furthermore, channel models, used for the exploring of their performances are described too. There was created an application with a graphical interface in MATLAB, which simulates transmission in DVB-C2. Based on simulations there are compared influences of each settings on bit error rate of data transmission for both standards. Finally, obtained simulation results are compared with theoretical values.
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Subjective quality evaluation of video sequences
Krmela, Tomáš ; Fliegel, Karel (referee) ; Polák, Ladislav (advisor)
This master´s work is focused on the comparison of subjective assessment of the quality of video sequences. In this study, data are obtained by hardware and sofware techniques and they are compared. In the introduction, methods of video compressions are described. The main part of this work deals wtih the exploring of different methods of subjective assessment of the quality of video sequences. Finally, obtained results from different methods, are evaluated and discussed.
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