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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

An insight to Level Communication through the use of Cameras : a Project Report

Lewis, Jonas January 2013 (has links)
The following paper is a documentation and project report of the construction of a project called Synergy. It details the underlying notion, investigation, procedure, and learning that lead to the construction, as well as the reflection upon a level design. Which purpose was to impose a heightened level of authorial control to its creator; thereby more fluidly conveying a creator's ambitions to its audience through the use of cinematographic cues. Upon the project's completion further investigations was done in respect to the finished product whereby I found that others had constructed similar systems, though not for the same cause.
32

Algorithms, Protocols & Systems for Remote Observation Using Networked Robotic Cameras

Qin, Ni 16 January 2010 (has links)
Emerging advances in robotic cameras, long-range wireless networking, and distributed sensors make feasible a new class of hybrid teleoperated/autonomous robotic remote "observatories" that can allow groups of peoples, via the Internet, to observe, record, and index detailed activity occurred in remote site. Equipped with robotic pan-tilt actuation mechanisms and a high-zoom lens, the camera can cover a large region with very high spatial resolution and allows for observation at a distance. High resolution motion panorama is the most nature data representation. We develop algorithms and protocols for high resolution motion panorama. We discover and prove the projection invariance and achieve real time image alignment. We propose a minimum variance based incremental frame alignment algorithm to minimize the accumulation of alignment error in incremental image alignment and ensure the quality of the panorama video over the long run. We propose a Frame Graph based panorama documentation algorithm to manage the large scale data involved in the online panorama video documentation. We propose a on-demand high resolution panorama video-streaming system that allows on-demand sharing of a high-resolution motion panorama and efficiently deals with multiple concurrent spatial-temporal user requests. In conclusion, our research work on high resolution motion panorama have significantly improve the efficiency and accuracy of image alignment, panorama video quality, data organization, and data storage and retrieving in remote observation using networked robotic cameras.
33

Adaptive Camera Tamper Detection For Video Surveillance

Saglam, Ali 01 June 2009 (has links) (PDF)
Criminals often resort to camera tampering to prevent capture of their actions. Many surveillance systems left unattended and videos surveillance system operators lose their concentration after a short period of time. Many important Real-time automated detection of video camera tampering cases is important for timely warning of the operators. Tampering can be defined as deliberate physical actions on a video surveillance camera and is generally done by obstructing the camera view by a foreign object, displacing the camera and changing the focus of the camera lens. In automated camera tamper detection systems, low false alarm rates are important as reliability of these systems is compromised by unnecessary alarms and consequently the operators start ignoring the warnings. We propose adaptive algorithms to detect and identify such cases with low false alarms rates in typical surveillance scenarios where there is significant activity in the scene. We also give brief information about the camera tampering detection algorithms in the literature. In this thesis we compare performance of the proposed algorithms to the algorithms in the literature by experimenting them with a set of test videos.
34

Digital camera calibration for mining applications

Jiang, Lingen Unknown Date
No description available.
35

A simple microcomputer-based nuclear medicine data processing system design and performance testing

Woldeselassie, Tilahun January 1990 (has links)
This thesis investigates the feasibility of designing a simple nuclear medicine data processing system based on an inexpensive microcomputer system, which is affordable to small hospitals and to developing countries where resources are limited. Since the main need for a computer is to allow dynamic studies to be carried out, the relevant criteria for choosing the computer are its speed and memory capacity. The benchmark chosen for these criteria is renography, one of the commonest nuclear medicine procedures. The Acorn Archimedes model 310 microcomputer was found to meet these requirements, and a suitable camera-computer interface has been designed. Because of the need for ensuring that the gain and offset controls of the interface are set optimally before connecting to the camera, it was necessary to design a circuit which produces a test pattern on the screen for use during this operation. Having also developed and tested the data acquisition and image display software successfully, atttention was concentrated on finding ways of characterising and measuring the performance of the computer interface and the display device, two important areas which have been largely neglected in the quality control of camera-computer systems. One of the characteristics of the interface is its deadtime. A procedure has been outlined for measuring this by means of a variable frequency pulse generator and also for interpreting the data correctly. A theoretical analysis of the way in which the interface deadtime affects the overall count rate performance of the system has also been provided. The spatial linearity, resolution and uniformity characteristics of the interface are measured using a special dual staircase generator circuit designed to simulate the camera position and energy signals. The test pattern set up on the screen consists of an orthogonal grid of points which can be used for a visual assessment of linearity, while analysis of the data in memory enables performance indices for resolution, linearity and uniformity to be computed. The thesis investigates the performance characteristics of display devices by means of radiometric measurements of screen luminance. These reveal that the relationship between screen luminance and display grey level value can be taken as quadratic. Characterisation of the display device in this way enables software techniques to be employed to ensure that screen luminance is a linear function of display grey level value; screen luminance measurements, coupled with film density measurements, are also used to optimise the settings of the display controls for using the film in the linear range of its optical densities. This in turn ensures that film density is a linear function of grey level value. An alternative approach for correcting for display nonlinearity is by means of an electronic circuit described in this thesis. Intensity coding schemes for improving the quality of grey scale images can be effective only if distortion due to the display device is corrected for. The thesis also draws attention to significant variations in film density which may have their origins in nonuniformities in the display screen, the recording film, or in the performance of the film processor. The work on display devices has been published in two papers.
36

Qualitative and quantitative aspect of multigated myocardial perfusion

Ballami, Nasser Salim January 1996 (has links)
No description available.
37

Digital camera calibration for mining applications

Jiang, Lingen 11 1900 (has links)
This thesis examines the issues related to calibrating digital cameras and lenses, which is an essential prerequisite for the extraction of precise and reliable 3D metric information from 2D images. The techniques used to calibrate a Canon PowerShot A70 camera with 5.4 mm zoom lens and a professional single lens reflex camera Canon EOS 1Ds Mark II with 35 mm, 85 mm, 135 mm and 200 mm prime lenses are described. The test results have demonstrated that a high correlation exists among some interior and exterior orientation parameters. The correlations are dependent on the parameters being adjusted and the network configuration. Not all of the 11 interior orientation parameters are significant for modelling the camera and lens behaviour. The first two coefficients K1, K2 would be sufficient to describe the radial distortion effect for most digital cameras. Furthermore, the interior orientation parameters of a digital camera and lens from different calibration tests can change. This work has demonstrated that given a functional model that represents physical effects, a reasonably large number of 3D targets that are well distributed in three-dimensional space, and a highly convergent imaging network, all of the usual parameters can be estimated to reasonable values. / Mining Engineering
38

On using airborne optical vertical polarisation to remove sea surface reflectance for enhanced visualisation of seagrass and other benthos.

Hart, David January 2009 (has links)
Mapping of marine benthic flora using remote sensing techniques has, over the past decade, been used to locate environmentally stressed areas in the South Australian marine environment. These studies used panchromatic/colour aerial photography and/or medium resolution multispectral satellite imagery to create a time series showing location and rate of seagrass loss. While successful within their project parameters, these studies were limited by conditions at time of image capture, such as sun-glare, wave action and low contrast in deeper waters due to absorption and scattering. This research thesis reports the successful use of polarisation on the capture of visible and near infra-red optical imagery as a method to minimise these limiting factors. Two experimental test flights were undertaken using commercial off-the-shelf digital cameras mounted in the camera port of a light aircraft. The first flight compared vertical polarisation using co-mounted visible and infra-red cameras. The second flight compared vertical and horizontal polarisation using co-mounted identical visible spectrum cameras. The main finding of this series of airborne polarisation experiments is that sea surface reflection is removed by using vertically polarised filters at, and around, the Brewster angle of 53 degrees off nadir, especially when viewing sunwards. The effect is the same in the visible and infra-red parts of the spectrum. This reflection includes sky reflectance, lambertian sun glare, reflection due to wave action, and turbulence, but not direct solar specular reflection. Vertical polarisation filters improve the imaging of benthic flora compared to horizontally polarised imagery and, by extension, non-polarised imagery. The successful use of polarisation to remove surface reflectance over water is limited to imagery captured at or near the Brewster angle. By using successive overlapping frames this can be achieved, as shown by the experiments. Ideally all of the image should be at the Brewster angle. A conceptual design for a conical optical scanner which builds wide-swath imagery where each pixel in each band is solely a record of the vertically polarised signal at the Brewster Angle is presented as a result of these experiments. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1374494 / Thesis (M.Sc.) - University of Adelaide, School of Earth and Environmental Sciences, 2009
39

Digital camera : an interactive tutorial /

Martinez i Colom, Roger. January 1993 (has links)
Thesis (M.F.A.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references (leaf 44).
40

Moderní trendy ve fotografii / Modern trends in photography

Ličmanová, Kateřina January 2014 (has links)
The aim of this thesis is to describe selected modern trends in photography and show their impact on society. The thesis describes the history of photography, sorting of digital cameras, and selected trends such as DSLR, mobile phones, selfie phenomenon, Polaroid, Lytro and aerial photography. In each trend there will be examples, users and financial demands.

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