National Repository of Grey Literature 56 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Methods and Tools for Image and Video Quality Assessment
Slanina, Martin ; Říčný, Václav (advisor)
Disertační práce se zabývá metodami a prostředky pro hodnocení kvality obrazu ve videosekvencích, což je velmi aktuální téma, zažívající velký rozmach zejména v souvislosti s digitálním zpracováním videosignálů. Přestože již existuje relativně velké množství metod a metrik pro objektivní, tedy automatizované měření kvality videosekvencí, jsou tyto metody zpravidla založeny na porovnání zpracované (poškozené, například komprimací) a originální videosekvence. Metod pro hodnocení kvality videosekvení bez reference, tedy pouze na základě analýzy zpracovaného materiálu, je velmi málo. Navíc se takové metody převážně zaměřují na analýzu hodnot signálu (typicky jasu) v jednotlivých obrazových bodech dekódovaného signálu, což je jen těžko aplikovatelné pro moderní komprimační algoritmy jako je H.264/AVC, který používá sofistikovené techniky pro odstranění komprimačních artefaktů. V práci je nejprve podán stučný přehled dostupných metod pro objektivní hodnocení komprimovaných videosekvencí se zdůrazněním rozdílného principu metod využívajících referenční materiál a metod pracujících bez reference. Na základě analýzy možných přístupů pro hodnocení video sekvencí komprimovaných moderními komprimačními algoritmy je v dalším textu práce popsán návrh nové metody určené pro hodnocení kvality obrazu ve videosekvencích komprimovaných s využitím algoritmu H.264/AVC. Nová metoda je založena na sledování hodnot parametrů, které jsou obsaženy v transportním toku komprimovaného videa, a přímo souvisí s procesem kódování. Nejprve je provedena úvaha nad vlivem některých takových parametrů na kvalitu výsledného videa. Následně je navržen algoritmus, který s využitím umělé neuronové sítě určuje špičkový poměr signálu a šumu (peak signal-to-noise ratio -- PSNR) v komprimované videosekvenci -- plně referenční metrika je tedy nahrazována metrikou bez reference. Je ověřeno několik konfigurací umělých neuronových sítí od těch nejjednodušších až po třívrstvé dopředné sítě. Pro učení sítí a následnou analýzu jejich výkonnosti a věrnosti určení PSNR jsou vytvořeny dva soubory nekomprimovaných videosekvencí, které jsou následně komprimovány algoritmem H.264/AVC s proměnným nastavením kodéru. V závěrečné části práce je proveden rozbor chování nově navrženého algoritmu v případě, že se změní vlastnosti zpracovávaného videa (rozlišení, střih), případně kodéru (formát skupiny současně kódovaných snímků). Chování algoritmu je analyzováno až do plného vysokého rozlišení zdrojového signálu (full HD -1920 x 1080 obrazových bodů).
Generators of the Measuring Signals sin220T and Sin22T
Mazánek, David ; Slanina, Martin (referee) ; Říčný, Václav (advisor)
My diploma thesis deals about the one possibility of distortion measuring in TV devices and distributions. The main objectives are analysis of special measuring signals sin220T and sin22T, means of precision assesments and design possibilities. Next point is proposal and after that draft of generator circuit. It will consist analog a digital section of processing measuring signals. Pulse sin22T is generated by digital decoder CPLD, trigged by “hardware” quartz oscilator 60MHz. Low-frequency component of signal sin220T have identical form like sin22T, diference is only in clocking by 10MHz assured by “software”frequency divider. High-frequency component of pulse is gained like product of AM modulation, that the modulation signal is low-frequency sin220T and harmonic carrier with frequency 4,433619MHz. Ocilator with automatic gain control (AGC) and quartz feed-back generates absolute accuracy oscillation (precision 10-6). Finaly this parts are summing in operation amplifier. Detailed analysis, draft and layout of PCB (Printed Circuid Board) is reffered – to diploma thesis.
Optoelectronic and photogrammetric measuring systems
Stančík, Petr ; Říčný, Václav (advisor)
Dissertation deals with analysis and design of optoelectronic and photogrammetric measuring systems. Specific design of optoelectronic contactless flat object area meters with analysis of attainable measurement accuracy is described. Next part is dedicated to stereophotogrammetry - principles of 3D reconstructions, methods of camera self-calibration and matching points in images are described. The analysis of attainable accuracy of monitored parameters is discussed too. Finally, the test program with implemented described routines is introduced. This test program enables practical aplication of stereophotogrammetric system for taking spatial coordinates of 3D objects.
System for Imaging of the Monochromatic Pictures in the Pseudo Color
Kaděrka, Petr ; Kratochvíl, Tomáš (referee) ; Říčný, Václav (advisor)
This diploma thesis treats the possibilities of the black-white picture depiction in pseudo colors (Pseudocolor). The individual methods, software or hardware are described there and the detailed block scheme of the system Pseudocolor is suggested. The block scheme is created on the basis of gained theoretical knowledge. In the thesis, individual functional blocks of the scheme are described and their circuit designs are realized. Some of the functional blocks are simulated by the PSpice program and accompanied by corresponding signal process data. The suitable choice of the active and passive components is performed, from which the general integration of the system Pseudocolor is made. All the source materials for the realization of the device are given there – double-sided drawing of the printed circuit, layout and specification of the components.
Determination of an area and proportions of selected objects in a picture
Mittner, Ondřej ; Stančík,, Petr (referee) ; Říčný, Václav (advisor)
The master’s thesis describes hardware opto-electronic instruments for contactless measurement of surfaces. It concentrates on instruments used for opto-electrical transformation of a taking scene and software processing of digital pictures. It presents selected methods of pre-processing, segmenting and following final modifications of these pictures. Then it deals with measuring of areas of surfaces and sizes of selected objects in these pictures and conversion of results from pixels to SI system of units. Possible divergences of measuring are described as well. A flow chart of a program for automatic and manual measuring of surfaces and sizes of objects in a picture, which is commented in detail, is a part of the thesis. The main product of this thesis is application Merovo, which provides measuring of an area and proportions of included objects. This application is analysed and described in detail in this thesis.
Speed and position measurement using optical and electromagnetic methods
Dvořák, Zdeněk ; Říčný, Václav (referee) ; Kratochvíl, Tomáš (advisor)
The project compares and describes the characteristics of optical and electromagnetic methods, used for measuring the object’s velocity. Some of these are used at the ballistic laboratory of PROTOTYPA, a.s. company. The rest is mentioned in order to increase the range of the project and are not engaged by the company. The practical part involves measuring and processing the magnetic fields of various appliances. There is a method and appliance designed to process the link between flying object and sensor.
Computer design of the small CATV
Sedláček, Jan ; Slanina, Martin (referee) ; Říčný, Václav (advisor)
Main task of this bachelor’s thesis is to create an interactive automatic programme for designing circuits of individual or small common television aerial. The first part of this document describes main conceptions distribution of television signals, parameters of coaxial cable and also some kinds of signals distortion. There are described some important mathematics formulas used for calculation of coaxial cable attenuation and carrier to noise distance important for computing function of programme. The second part describes a procedure of designing of television cable circuit of individual or small common television aerial and includes prototypal calculation of two real circuits and its comparison with results of computer calculation by which correct function of programme is verified. A part of this document is also made by detailed description of programme and its functions. Source code of created programme is included in the end of this document.
Remote switching of electrical appliances by the mobile phone
Hrabina, Martin ; Boleček, Libor (referee) ; Říčný, Václav (advisor)
The concern of this work is GSM remote control. First part is summary of requirements and possible solutions of given problem, discussing their complexity and tolerance against interference and unauthorized switching. Also, in the first part, there is selected one solution which is discussed in detail. Second part of the work consists of theoretical and circuitry design of GSM remote switch itself. End of this work is dedicated to the construction of whole device and checking its functionality.
Contactless meter of the water level
Pálka, Václav ; Boleček, Libor (referee) ; Říčný, Václav (advisor)
This paper describes the design and construction issues contactless meter water level in an enclosure (typically well) in distance measurement units of meters. The work includes theoretical analysis of possible ways to measure and describe the design, along with the design of individual functional blocks and verifying their function
Measurements of the object position and velocity by using optical scanners
Uncajtik, Petr ; Říčný, Václav (referee) ; Kratochvíl, Tomáš (advisor)
The objective of Master’s Thesis is to research the utilization of line optical sensors for object location´s and speed measurement in cooperation with PROTOTYPA company. At the beginning of the Thesis there is an explanation of CCD sensor components and photodiods working principals. Further are discussed particular methods of object sensing. There are schematics of different sensor locations and flying object. The other step deals with introduction to the question of ray impact on sensor in the way of using different light sources and optical systems. In the other part of the Thesis are presented two sensors, which have been chosen by PROTOTYPA company workers. Final part of the Thesis deals with description of executed experimental measurement with LCCD 2048S-14 type of sensor. Experiments are aimed for statical and dynamical processes. In statical part was checked displaying of fixed objects on CCD sensor in internal spaces on the assumption that changing of object-lens focalization, object´s high and shape. For the evaluation was used of MATLAB program. Dynamical part of measurement is aimed for moving objects.

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