Dissertations / Theses on the topic 'Human visual system'
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1
Ledeatte, Barry Anderson. "Spatial summation in the human visual system." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243775.
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Turner, Stuart L. "Coupling retinal scanning displays to the human visual system : visual system response and engineering considerations /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/10686.
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Qi, Huiyan. "Human visual system based adaptive digital image watermarking." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27287.
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It is known that the fidelity of the image is inversely proportional to the robustness of the watermark. Therefore, there should be the trade off between fidelity for robustness and vise versa. Based on the new spatial masking we explored in this thesis, a new adaptive digital image watermarking method is proposed. It keeps the invisibility of the watermark and maintains its robustness at the same time. The new spatial masking is built according to the image features such as flat areas with big brightness or darkness, edges, and regions with high activities. With the same watermarking energy, the quality of water-marked image with this masking is much better than the one without it. We also propose using the weighted Peak Signal-to-Noise Ratio (wPSNR) to evaluate the image quality. The watermark is detected by the key-dependent method without knowing the original image information. In addition, we extend this proposed spatial masking to the Discrete Cosine Transform (DCT) domain by using the method of searching the extreme value of the quadratic function subject to the bounds on the variables.
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Hutchinson, S. J. "Spatio-chromatic interactions in the human visual system." Thesis, Queen's University Belfast, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.411198.
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Petrova, D. "Non-invasive dissection of the human visual system." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1310438/.
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A flickering stimulus can appear brighter or of different colour than a steady stimulus of the same spectral composition and equal time-averaged intensity. The change in appearance is consistent with the distortion product of a nonlinearity in the human visual system. This nonlinearity is used for non-invasive dissection of the human visual system into prenonlinearity and post-nonlinearity linear stages, which affect the amplitude of the sinusoidal signals that they process. A five-channel Maxwellian system was used to generate cosine-windowed, amplitude-modulated, sinusoidally-flickering stimuli. The subjects adjusted the maximum modulation of the signal in order to set the threshold for the perception of flicker and colour or brightness change. The pre-nonlinearity filter was tested by varying the carrier frequency between 5 Hz and 60 Hz and the post-nonlinearity filter was measured by varying the amplitude-modulation frequency between 0.25 Hz and 5 Hz. The L- and M-cone pathways are separately measured by using a new combination of the silent-cone-substitution technique and the sandwich model. The distortion product at the output of the nonlinearity is measured by using a new matching method for measuring the colour and brightness changes. The results suggest that the pre-nonlinearity filter is band-pass and shows substantial adaptation with light intensity that can explain most of the adaptation in the visual pathways. The post-nonlinearity filter is low-pass and shows little or no adaptation with light intensity. The input-output function of the nonlinearity can be described as an expansive, quadratic function that rapidly saturates at high input levels.
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Pixton, Bruce. "Spherical Aberration Gauge for the Human Visual System." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/194351.
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Spherical aberration limits the ability of a human eye to form a clear image. The amount of Spherical Aberration found in a given eye is different across a population and is actively changing as a function of accommodation, light level, and age. Any attempt made to correct spherical aberration will need to have an accurate understanding of what the appropriate correction should be. Objective measurement of the Spherical Aberration inherent to the eye's optical systems helps to answer part of the question, but there are other factors in the human visual system, such as processing in the brain that affect what is "seen". Hence, a vision correction approach based purely on objective measurement of the eye's aberrations may not necessarily correspond to better vision. The Spherical Aberration Gauge has been developed to allow subjects to deter- mine for themselves the appropriate amount of correction required. The Gauge is designed to allow users to view an eye chart or scene while adjusting the amount of spherical aberration being introduced. It produces a wide range of spherical aberration levels from which a user can determine a single level that provides best vision. The amount selected by the user is considered a subjective spherical aberration correction and can then be applied to standard vision correction devices or procedures. This project attempts to bridge the gap between what is known about ocular spherical aberration and how the brain interprets the correction. The outcome of this project is to provide a tool that identifies the preferred amounts of spherical aberration correction and that gives insight from subjective feedback on the visual benefit thereof.
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Ditye, T. "Learning-dependent plasticity in the human visual system." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1419268/.
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The capability to change is an inherent property of the human brain. Plastic processes occur throughout the central nervous system and are a requirement for development, learning, and the formation of memories. The research presented in this thesis examined learning-dependent plasticity in the visual system. Mechanisms of interest included structural and functional brain plasticity, adaptation, and the facilitating functions of sleep in supporting the processing, implementation, and organisation of newly learned information and experiences. Some of the most traditional experimental paradigms such as visual search, sensory adaptation, and texture discrimination were utilised to trigger learning and the accompanying changes in behaviour, neural function, and brain anatomy. Results based on behavioural data and high-resolution brain imaging data showed that training in a variety of visual tasks can result in characteristic short-term adjustments of cortical volume and myelination in task-relevant brain regions which can be correlated with individual improvements in task performance. Our research further demonstrated that sleep is a requirement for the integration of adaptive visual experiences, thereby linking adaptation---a mechanism usually not considered to play a role in mnemonic processes---with learning and memory.
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Apaydin, Mehmetcan. "Biologically Inspired Multichannel Modelling Of Human Visual Perceptual System." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606772/index.pdf.
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Making a robot autonomous has been a common challenge to be overcome since the very beginning. To be an autonomous system, the robot should collect environmental data, interpret them, and act accordingly. In order to accomplish these, some resource management should be conducted. That is, the resources, which are time, and computation power in our case, should be allocated to more important areas.
Existing researches and approaches, however, are not always human like. Indeed they don&rsquot give enough importance on this. Starting from this point of view, the system proposed in this thesis supplies the resource management trying to be more &rsquo
human like&rsquo
. It directs the focus of attention to where higher resolution algorithms are really needed. This &rsquo
real need&rsquo
is determined by the visual features of the scene, and current importance levels (or weight values) of each of these features. As a further attempt, the proposed system is compared with human subjects&rsquo
characteristics. With unbiased subjects, a set of parameters which resembles a normal human is obtained. Then, in order to see the effect of the guidance, the subjects are asked to concentrate on a single predetermined feature. Finally, an artificial neural network based learning mechanism is added to learn to mimic a single human or a group of humans. The system can be used as a preattentive stage module, or some more feature channels can be introduced for better performance in the future.
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Chen, Yuping. "Improved frequency response measurements in the human visual system." FIU Digital Commons, 1994. http://digitalcommons.fiu.edu/etd/2151.
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The temporal frequency response characteristics of the human visual system have been investigated by combining the increment threshold and sinusoidal flicker methods. Gain and phase spectra were obtained for two subjects using improved equipment and methodology compared with previous investigations. While the output of the system for sinusoidal input stimuli was generally also sinusoidal, as required for a linear system, other non-linearities emerged. Gain spectra for both subjects indicated a low-pass filtering action. Phase spectra showed a possible low frequency phase lead followed by a high frequency lag. Earlier studies suggested that the system might be a minimum phase system and, as such, would allow the phase spectrum to be derived from the gain spectrum via the Kramers-Kronig relations. This possibility was examined in light of the measured gain and phase spectra and found to be implausible.
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Gonzalez, Alvaro J. "Alpha stable human visual system models for digital halftoning." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 58 p, 2007. http://proquest.umi.com/pqdweb?did=1251904881&sid=3&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Tschirner, Petra [Verfasser]. "Human Visual System-Based Image Contrast Enhancement / Petra Tschirner." Aachen : Shaker, 2005. http://d-nb.info/1186580119/34.
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Owens, Huw Christopher. "Colour and spatiochromatic processing in the human visual system." Thesis, University of Derby, 2002. http://hdl.handle.net/10545/295217.
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Fergusson, Robert Johnstone. "Human visual system based object extraction for video coding." Thesis, University of Strathclyde, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366673.
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Owen, Kathrin Angela. "The coding of motion in the human visual system." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285974.
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Tadmor, Yoav. "Processing of natural images by the human visual system." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385855.
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Kaul, C. E. "Studying feature specific mechanisms of the human visual system." Thesis, University College London (University of London), 2010. http://discovery.ucl.ac.uk/19700/.
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What are the current limits of our knowledge of brain activity underlying vision and can I further this knowledge? In this thesis, I explore this basic question. I focus on those aspects of visual input that can be described as basic features of visual perception. Examples include orientation, color, direction of motion and spatial frequency. However, understanding how humans visually perceive the external world is closely related with the study of attention. Attention, that is, the selection of some aspects of the environment over others, is one of the most intensively studied areas in experimental psychology, yet its neural mechanisms remain largely elusive. This thesis focuses on three distinct topics at the border of feature specific visual perception and feature-specific visual attention. First, in a series of studies, I explore the influence of heightened attentional demand to a central task to feature-specific neural processing in the ignored periphery. I discover that heightened attentional demand does not influence feature-specific representations in early visual cortices. Second, I investigate the influence of feature-based attention on neural processing of early visual cortices. At the same time, I also probe the influence of a behavioral decision to deploy feature-specific attention in the imminent future. I find that feature-based attention operates independent of other types of attention. Additionally, results indicate that a behavioral decision to deploy feature-based attention alone, without visual stimulation present, is able to modulate neural activity in early visual cortices. Third, I examine the more complex feature of facial gender and where in the brain gender discrimination might receive neural processing. I find that, in an established network of face-selective brain areas, facial gender is represented in nearly all areas of that network. Finally, I discuss all findings in the light of the current state of research, for their scientific significance and for future research opportunities.
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Beegan, Andrew Peter. "Wavelet-based Image Compression Using Human Visual System Models." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/32939.
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Recent research in transform-based image compression has focused on the wavelet transform due to its superior performance over other transforms. Performance is often measured solely in terms of peak signal-to-noise ratio (PSNR) and compression algorithms are optimized for this quantitative metric. The performance in terms of subjective quality is typically not evaluated. Moreover, the sensitivities of the human visual system (HVS) are often not incorporated into compression schemes.
This paper develops new wavelet models of the HVS and illustrates their performance for various scalar wavelet and multiwavelet transforms. The performance is measured quantitatively (PSNR) and qualitatively using our new perceptual testing procedure.
Our new HVS model is comprised of two components: CSF masking and asymmetric compression. CSF masking weights the wavelet coefficients according to the contrast sensitivity function (CSF)---a model of humans' sensitivity to spatial frequency. This mask gives the most perceptible information the highest priority in the quantizer. The second component of our HVS model is called asymmetric compression. It is well known that humans are more sensitive to luminance stimuli than they are to chrominance stimuli; asymmetric compression quantizes the chrominance spaces more severely than the luminance component.
The results of extensive trials indicate that our HVS model improves both quantitative and qualitative performance. These trials included 14 observers, 4 grayscale images and 10 color images (both natural and synthetic). For grayscale images, although our HVS scheme lowers PSNR, it improves subjective quality. For color images, our HVS model improves both PSNR and subjective quality. A benchmark for our HVS method is the latest version of the international image compression standard---JPEG2000. In terms of subjective quality, our scheme is superior to JPEG2000 for all images; it also outperforms JPEG2000 by 1 to 3 dB in PSNR.Master of Science
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Thakur, Mahesh Kumar Singh. "Advanced Color Projector Design Based on Human Visual System." University of Dayton / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1324514021.
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Wheeler, Collin P. "Spectral qualities of light: effects on human perception and the human visual system." Kansas State University, 2016. http://hdl.handle.net/2097/32488.
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Master of ScienceArchitectural Engineering and Construction Science
Fred Hasler
By definition, light is a metric created solely for the visual response of human beings. As a result, nearly every lighting metric is weighted to accurately depict human responses. The first human visual response function was adopted in 1924 by the CIE, V(λ), and is still the primary function weighting for all other lighting metrics. However, V(λ) has obvious limitations, one being that it only includes contributions from long- and medium-wavelength photoreceptors. Therefore, V(λ) cannot accurately provide indication to visual acuity (VA). Because vision is a sense that humans rely so heavily on, causes for optimal vision are valued in order to create artificially lit spaces that emulate qualities on which the human visual systems thrives. One factor of VA is pupillary diameter, which is dictated by many factors ranging from light spectra to emotional states. The formula P(S/P)ˣ was derived to predict how average pupil size is influenced by general light spectra. Generally, the smaller the pupil, the greater VA. Per the formula, increased scotopic (V’(λ)) lumens result in smaller pupils. A rearrangement of the P(S/P)ˣ formula provided a mathematical means for quantifying an illuminance reduction, later established by the IES as Equivalent Visual Efficiency (EVE) Factors. In theory, acceptable reduced illuminance levels result in less energy consumed. Not everyone saw the benefits of spectrally enhanced lighting though; the practicality, extent of application, and actual preference of light sources that allow the usage of EVE Factors remain a polarized subject. Intrinsically photosensitive retinal ganglion cells (ipRGC) were discovered in 2002, after the derivation of the P(S/P)ˣ formula. However, they are known to play a role in pupil size. Emotional and ipRGC contributions to pupil size are ambiguities that prove a weak point in the argument for reducing illuminance levels. Overall, this report compiles and analyzes research over the past century. Initially, background information on light, metrics, light sources, and human biology is introduced. Then specifics on human vision follow. Arguments for and against IES EVE Factors are presented, and ultimately, a recommendation is provided on the implementation of EVE Factors. The Appendix houses example EVE calculations and values.
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Mihaylov, Petar. "Investigation of long-range interactions in the human visual system." Thesis, Glasgow Caledonian University, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.547413.
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Nguyen, Phi Bang. "On The Use of Human Visual System Modelling in Watermarking." Paris 13, 2011. http://www.theses.fr/2011PA132035.
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De nos jours, la facilité de diffusion des contenus numériques offre de grandes possibilités de création mais également de reproduction illégale (contrefaçon) des œuvres. Cette banalisation des outils de capture et de manipulation de contenus numériques a des conséquences néfastes sur la société et l'économie. Pour faire face à ce problème, plusieurs solutions matérielles et immatérielles ont été proposées. Parmi les techniques connues, la cryptographie et le tatouage sont deux solutions complémentaires. Dans le cadre de cette thèse, nous nous intéressons plus particulièrement à la solution de tatouage numérique. Il y a en général, deux critères principaux qu'un système de tatouage doit satisfaire: la robustesse et la transparence. Cependant, ces deux critères ne peuvent pas être satisfaits simultanément de façon optimale. En effet, plus la robustesse est forte, plus les dégradations introduites par le tatouage sont visibles et vice versa. Pour pallier à ce problème, nous nous sommes orientés vers une approche perceptuelle qui utilise quelques caractéristiques du SVH (Système Visuel Humain) pour trouver un compromis optimal entre la robustesse et la transparence. L'idée de base consiste à exploiter les limitations du SVH pour contrôler la visibilité de la marque insérée ainsi que pour trouver les zones stratégiques d'insertion. Une étude statistique de la performance des métriques de qualité utilisées dans le tatouage sont aussi proposées. Les résultats obtenus sont très encourageants et démontrent l'efficacité de l'approche développéeNowadays, the easy distribution of digital content offers great opportunities for creativity, but also counterfeiting. This causes a negative impact on the society and the global economy. To address this problem, various protection solutions have been developed. Cryptography and watermarking are considered as two complementary techniques for such solutions. In the framework of this thesis, we concentrate on digital watermarking. One of the main issues in watermarking is to solve the trade-off between robustness and imperceptibility. However, these two criteria cannot be achieved simultaneously. Indeed, the stronger the watermark strength, the more the degradation is. To overcome this problem, we rely on an approach that exploits the perceptual characteristics of the HVS (Human Visual System) to find an optimal trade-off between these two conflicting criteria. The basic idea is to incorporate some limitations of the HVS to embed the watermark according to some perceptual criteria in order to guarantee its robustness and transparency. A statistical study on the performance of image quality metrics used in watermarking are also proposed. The obtained results are very promising and demonstrate the efficiency of the proposed approach
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Baldwin, Alexander. "Pattern integration in the normal and abnormal human visual system." Thesis, Aston University, 2013. http://publications.aston.ac.uk/19296/.
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The processing conducted by the visual system requires the combination of signals that are detected at different locations in the visual field. The processes by which these signals are combined are explored here using psychophysical experiments and computer modelling. Most of the work presented in this thesis is concerned with the summation of contrast over space at detection threshold. Previous investigations of this sort have been confounded by the inhomogeneity in contrast sensitivity across the visual field. Experiments performed in this thesis find that the decline in log contrast sensitivity with eccentricity is bilinear, with an initial steep fall-off followed by a shallower decline. This decline is scale-invariant for spatial frequencies of 0.7 to 4 c/deg. A detailed map of the inhomogeneity is developed, and applied to area summation experiments both by incorporating it into models of the visual system and by using it to compensate stimuli in order to factor out the effects of the inhomogeneity. The results of these area summation experiments show that the summation of contrast over area is spatially extensive (occurring over 33 stimulus carrier cycles), and that summation behaviour is the same in the fovea, parafovea, and periphery. Summation occurs according to a fourth-root summation rule, consistent with a “noisy energy” model. This work is extended to investigate the visual deficit in amblyopia, finding that area summation is normal in amblyopic observers. Finally, the methods used to study the summation of threshold contrast over area are adapted to investigate the integration of coherent orientation signals in a texture. The results of this study are described by a two-stage model, with a mandatory local combination stage followed by flexible global pooling of these local outputs. In each study, the results suggest a more extensive combination of signals in vision than has been previously understood.
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Heckman, Genevieve Marie. "Neural mechanisms of color appearance in the human visual system." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1432771461&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Beauchamp, Michael S. "FMRI of attention in the human visual motion processing system /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1997. http://wwwlib.umi.com/cr/ucsd/fullcit?p9805792.
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Chen, Xiaoyu. "Multiscale Quantitative Analytics of Human Visual Searching Tasks." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/104200.
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Benefit from the recent advancements of artificial intelligence (AI) methods, industrial automation has replaced human labors in many tasks. However, humans are still placed in the central role when visual searching tasks are highly involved for manufacturing decision-making. For example, highly customized products fabricated by additive manufacturing processes have posed significant challenges to AI methods in terms of their performance and generalizability. As a result, in practice, human visual searching tasks are still widely involved in manufacturing contexts (e.g., human resource management, quality inspection, etc.) based on various visualization techniques. Quantitatively modeling the visual searching behaviors and performance will not only contribute to the understanding of decision-making process in a visualization system, but also advance AI methods by incubating them with human expertise. In general, visual searching can be quantitatively understood from multiple scales, namely, 1) the population scale to treat individuals equally and model the general relationship between individual's physiological signals with visual searching decisions; 2) the individual scale to model the relationship between individual differences and visual searching decisions; and 3) the attention scale to model the relationship between individuals' attention in visual searching and visual searching decisions. The advancements of wearable sensing techniques enable such multiscale quantitative analytics of human visual searching performance. For example, by equipping human users with electroencephalogram (EEG) device, eye tracker, and logging system, the multiscale quantitative relationships among human physiological signals, behaviors and performance can be readily established.
This dissertation attempts to quantify visual searching process from multiple scales by proposing (1) a data-fusion method to model the quantitative relationship between physiological signals and human's perceived task complexities (population scale, Chapter 2); (2) a recommender system to quantify and decompose the individual differences into explicit and implicit differences via personalized recommender system-based sensor analytics (individual scale, Chapter 3); and (3) a visual language processing modeling framework to identify and correlate visual cues (i.e., identified from fixations) with humans' quality inspection decisions in human visual searching tasks (attention scale, Chapter 4). Finally, Chapter 5 summarizes the contributions and proposes future research directions.
The proposed methodologies can be readily extended to other applications and research studies to support multi-scale quantitative analytics. Besides, the quantitative understanding of human visual searching behaviors performance can also generate insights to further incubate AI methods with human expertise. Merits of the proposed methodologies are demonstrated in a visualization evaluation user study, and a cognitive hacking user study. Detailed notes to guide the implementation and deployment are provided for practitioners and researchers in each chapter.Doctor of Philosophy
Existing industrial automation is limited by the performance and generalizability of artificial intelligence (AI) methods. Therefore, various human visual searching tasks are still widely involved in manufacturing contexts based on many visualization techniques, e.g., to searching for specific information, and to make decisions based on sequentially gathered information. Quantitatively modeling the visual searching performance will not only contribute to the understanding of human behaviors in a visualization system, but also advance the AI methods by incubating them with human expertise. In this dissertation, visual searching performance is characterized from multiple scales, namely, 1) the population scale to understand the visual searching performance in regardless of individual differences; 2) the individual scale to model the performance by quantifying individual differences; and 3) the attention scale to quantify the human visual searching-based decision-making process. Thanks to the advancements in wearable sensing techniques, this dissertation attempts to quantify visual searching process from multiple scales by proposing (1) a data-fusion method to model the quantitative relationship between physiological signals and human's perceived task complexities (population scale, Chapter 2); (2) a recommender system to suggest the best visualization design to the right person at the right time via sensor analytics (individual scale, Chapter 3); and (3) a visual language processing modeling framework to model humans' quality inspection decisions (attention scale, Chapter 4). Finally, Chapter 5 summarizes the contributions and proposes future research directions. Merits of the proposed methodologies are demonstrated in a visualization evaluation user study, and a cognitive hacking user study. The proposed methodologies can be readily extended to other applications and research studies to support multi-scale quantitative analytics.
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Snelgar, Rosemary S. "Aspects of chromatic and temporal processing in normal and impaired human vision." Thesis, Keele University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329085.
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Cockle, Sarah Michelle. "The role of the cholinergic modulation system in human visual attention." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286224.
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Prince, Simon J. D. "Measurement and encoding of binocular disparity in the human visual system." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.299231.
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Ledgeway, Timothy. "The detection of second-order motion in the human visual system." Thesis, Cardiff University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318558.
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Han, Yena. "Invariance properties of the human visual system in one-shot learning." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/119589.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 45-46).
This work first characterizes human invariant recognition in one-shot learning. By using novel stimuli, we address the question whether invariance to transformation emerges from experience and memorization of templates or from the brain instantly computing invariant representation. Our psychophysical experimental results suggest that human vision produces a representation that is robust in terms of scale change, but it needs experience for translation-invariance. Next, we examine the implication of the experimental data with regards to computational modeling. In particular, we confirm that the eccentricity-dependent model [16], where scale-invariance is built in the underlying architecture, reproduces the human data closely.
Funded by NSF STC award CCF-1231216
by Yena Han.
M. Eng.
31
Alvarez, Ferreira I. A. "Functional and structural organisation of the visual system in human albinism." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1543205/.
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Albinism is a developmental disorder which involves the misrouting of optic nerve projections, leading to an abnormally organised visual system. Despite the aberrant input, people with albinism have relatively normal vision and experience the world in much the same way as their peers. This thesis explores the functional and structural organisation of visual cortex in human albinism using magnetic resonance imaging (MRI) techniques. This thesis covers four main experiments. Experiment 1 deals with stimulus optimisation for population receptive field (pRF) mapping in healthy adults. pRF mapping is a functional MRI technique for estimating cortical receptive field characteristics non-invasively. In this experiment, a stimulus configuration optimized for short acquisition time requirements is presented and implemented in subsequent experiments. Experiment 2 combines the pRF approach for retinotopic localization with diffusion MRI tractography in healthy adults to show evidence for direct extrastriate connections of the human optic radiation. The optic radiation is the principal white matter pathway for relaying retinal input to visual cortex, and typically considered a projection to primary visual cortex. In this experiment, independent pathways of the optic radiation to visual areas V2 and V3 are identified, and functional-structural methodologies developed for Experiment 4. Experiment 3 investigates the functional organisation of visual cortex in participants with albinism. A pRF mapping approach was implemented, identifying abnormal retinotopic organisation and altered receptive field properties in extrastriate visual cortex. In addition, we explore evidence for and against a dual receptive field model of visual field representation in albinism. Experiment 4 examines the structural and functional connectivity of early visual system in human albinism. In particular, differences in white matter microstructure and inter- hemispheric visual map connectivity are found between participants with albinism and a cohort of healthy controls. This thesis highlights the capacity and limitations of developmental plasticity in human albinism.
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Leat, Susan Jennifer. "A study of central and eccentric visual perception : ocular dominance and contrast matching." Thesis, Cardiff University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278804.
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Wishart, Keith A. "Cue combination for depth, brightness and lightness in 3-D scenes." Thesis, University of Sheffield, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389616.
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Seay, Christina Ann. "The mechanisms of superposed and lateral masking in the human visual system /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Gabbott, P. L. A. "Quantitative neurohistological correlates of visual deprivation in the visual system of the rat and GABA immunocytochemistry of the rat cerebellum and dorsal lateral geniculate nucleus." Thesis, Open University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354999.
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Oh, Joonmi. "Human visual system informed perceptual quality assessment models for compressed medical images." Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368425.
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Hospital and clinical environments are rapidly moving toward the digital capture, processing, storage, and transmission of medical images. X-ray cardio-angiograms are used to observe coronary blood flow, diagnose arterial disease and perform coronary angioplasty or bypass surgery. The digital storage and transmission of these cardiovascular images has significant potential to improve patient care. For example, digital images enable electronic archiving, network transmission and useful manipulation of diagnostic information such as image enhancement. The efficient compression of medical images is tremendously important for economical storage and fast transmission, since digitised medical images must be of high-quality, requiring high-resolution and having a large volume in general. The use of lossily compressed images has created a need for the development of objective quality assessment metrics I measuring perceived subjective opinions by viewers for optimal compression rate/distortion trade-off. Quality assessment metrics, based on models of the human visual system, have more accurately predicted perceived quality than traditional error-based objective quality metrics. This thesis presents a proposed Multi-stage Perceptual Quality Assessment (MPQA) model for compressed images. The motivation for the development of a perceptual quality assessment is to measure (in)visible physical differences between original and processed images. MPQA produces visible distortion maps and quantitative error measured informed by considerations of the human visual system. Original and decompressed images are decomposed into different spatial frequency bands and orientations modelling the human cortex. Contrast errors are calculated for each frequency and orientation, and masked as a function of contrast sensitivity and background uncertainty. Spatially masked contrast error measurements are made across frequency bands and orientations to produce a single Perceptual Distortion Visibility Map (PDVM). A Perceptual Quality Rating (PQR) is calculated from the PDVM and transformed into a one to five scale for direct comparison with the Mean Opinion Score (MOS), generally used in subjective rating. For medical applications, acceptable decompressed medical images might be those which are perceptually pleasing, contain no visible artefacts and have no loss in diagnostic content. To investigate this problem, clinical tests identifying diagnostically acceptable image reconstructions is performed and demonstrates that the proposed perceptual quality rating method has better agreement with observers' responses than objective error measurement methods. The vision models presented in the thesis are also implemented in the thresholding and quantisation stages of a compression algorithm. An HVS-informed perceptual thresholding and quantisation method is also shown to produce improved compression ratio performance with less visible distortions.
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Wolf, Janet Elizabeth. "Identification of defects in specific parallel #channels' of the human visual system." Thesis, City University London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319690.
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Tomoszek, A. "Spatial properties of fine-grain movement perception in the human visual system." Thesis, Keele University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293525.
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Oh, Han. "Visually Lossless Compression Based on JPEG2000 for Efficient Transmission of High Resolution Color Aerial Images." International Foundation for Telemetering, 2010. http://hdl.handle.net/10150/605962.
Full textAbstract:
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, CaliforniaAerial image collections have experienced exponential growth in size in recent years. These high resolution images are often viewed at a variety of scales. When an image is displayed at reduced scale, maximum quantization step sizes for visually lossless quality become larger. However, previous visually lossless coding algorithms quantize the image with a single set of quantization step sizes, optimized for display at the full resolution level. This implies that if the image is rendered at reduced resolution, there are significant amounts of extraneous information in the codestream. Thus, in this paper, we propose a method which effectively incorporates multiple quantization step sizes, for various display resolutions, into the JPEG2000 framework. If images are browsed from a remote location, this method can significantly reduce bandwidth usage by only transmitting the portion of the codestream required for visually lossless reconstruction at the desired resolution. Experimental results for high resolution color aerial images are presented.
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Olgun, Ferhat Ramazan. "Evaluation Of Visual Quality Metrics." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613733/index.pdf.
Full textAbstract:
The aim of this study is to work on the visual quality metrics that are widely
accepted in literature, to evaluate them on different distortion types and to give a
comparison of overall performances in terms of prediction accuracy, monotonicity,
consistency and complexity. The algorithms behind the quality metrics in literature
and parameters used for quality metric performance evaluations are studied. This
thesis also includes the explanation of Human Visual System, classification of visual
quality metrics and subjective quality assessment methods. Experimental results that
show the correlation between objective scores and human perception are taken to
compare the eight widely accepted visual quality metrics.
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Guerra, Paradas Edmundo. "Monocular SLAM : data association and sensing through a human-assisted uncalibrated visual system." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/457636.
Full textAbstract:
The Simultaneous Localization and Mapping (SLAM) problem is widely acknowledged as one of the fundamental problem to solve in perception and robotics to produce actual mobile robotic agents. The problem itself is that of how can a mobile robot agent operate in an a priori unknown environment, using the sensory systems available (normally on itself) to perceive its surroundings, build a map with this knowledge, and localize itself in said map tracking its own position.
This relevance, combined with the diversity of approaches available to solve it, and the depth of the challenges it presents, makes the SLAM problem one of the more active areas of research in robotics. One of the most complex challenges in any approach is the data association, as it generally conveys hard a trade-off between robustness and computational time required, and can impact the whole architecture of a SLAM method.
In terms of sensors used, the field was originally dominated by range finder sensors, but visual SLAM research has grown in popularity in the last decade. Camera sensors have been expanding its capabilities and specifications thanks to the consumer demand for them. As a sensor, they provide lightning measurements of the projected points at known bearings, which through computer vision can be converted into bearing measurements for visual features, which can be themselves of several levels of complexity.
The same consumer demand has also pushed technical developments in MEMS and robotic devices with a direct impact in the field of cooperative robotics and the emergence of wearable device technology, where human can wear or carry devices with several sensors in an unobtrusive way. These technologies have opened many opportunities in for research in robotics, including the field of collaborative SLAM and the area of human-robot interaction (HRI).
This thesis is focused in the study and development of a visual SLAM methodology based on the delayed inverse-depth feature initialization (DI-D) monocular SLAM which can benefit and exploit the advantages of working in a HRI collaborative framework. In order to achieve this, the research is focused in two different areas. Firstly, the known and tested DI-D monocular SLAM is studied: its procedures and algorithms detailed and analyzed; with emphasis in the data association problem (DA). The DA process is reviewed, and a new validation algorithm is introduced to strengthen and give robustness to the data association technique used.
Once the DI-D has been studied and updated the HRI collaborative framework is introduced, with an initially focus into solving one of its inconveniences: the requirement of a scaled metric initialization with a priori knowledge. The HRI is introduced by deploying into a human being a custom built wearable device which includes a camera and some other sensors. The data from this secondary monocular sensor, whose pose is approximately known with respect to the camera used to solve the SLAM problem, allows speeding up the feature initialization process of the DI-D, and even ignoring the requirement of scale initialization.
As the introduction of the HRI framework was successful, its advantages were further expanded to the rest of the SLAM process, including the measurement and update steps. This integration was performed based in a virtual sensor methodology, where the collaborative measurement process was treated as a single sensor with its specifications, allowing seamless fusion into the EKF-SLAM (Extended Kalman Filter SLAM). To evaluate the specific impact of the HRI with respect to the behaviour of the secondary camera, several new metrics have been proposed and studied.
All the methods have been proved and validated through experimentation with real data. When it was found relevant, the experiments were evaluated in real-time scenarios, and several simulations have been included when needed to prove some theoretical hypothesis.El problema de Localización y Mapeado Simultáneos (SLAM) es ampliamente reconocido como uno de los desafíos fundamentales a resolver en los campos de percepción y robótica autónomas para llegar a producir agentes robóticos móviles. El problema en si trata de como un robot podría, en un entorno a priori desconocido, construir un mapa con la información disponible vía sus sensores, y localizarse y navegar con respecto a este mismo mapa, estimando su posición. La importancia de este problema, junto con la gran variedad de estrategias y la complejidad de los subproblemas que plantean, hace que el campo de SLAM sea una de las áreas más activas de investigación en robótica. Uno de los mayores desafíos dentro del campo de SLAM, que comparte con otros ámbitos de la robótica y la percepción autónoma, es el problema de Asociación de Datos (data association, DA); ya que normalmente implica un precario equilibrio entre la eficacia y robustez de los resultados obtenidos, y la potencia y tiempo de cálculos necesarios para llegar a ellos, siendo un factor determinante en muchas estrategias de SLAM. En cuanto a sensores usados, el campo ha sido dominado por telémetros de barrio, pero durante la última década la investigación en SLAM visual produjo estrategias de gran impacto. Esto se debe en gran medida a que la demanda para el consumo de sensores de cámara ha incrementado sus prestaciones y bajado sus precios. La cámara, como sensor, produce mediciones de intensidad lumínica sobre puntos proyectados en orientaciones conocidas, que pueden convertirse en mediciones sobre características visuales aplicando métodos de visión por computador. Estas características visuales suelen ser puntos, pero pueden presentar múltiples niveles de complejidad. La misma demanda de los mercados ha impulsado el desarrollo de sensores micro-electro-mecánicos y otros dispositivos robóticos que han contribuido a desarrollar la robótica colaborativa y las tecnologías de dispositivos vestibles (wearable). Éstas tecnologías han abierto muchos campos de investigación dentro del problema de SLAM, como por ejemplo el SLAM colaborativo y el basado en interacción robot-humano (human-robot interaction, HRI). Esta tesis se centra en el estudio y desarrollo de un método de SLAM visual basado en la técnica delayed inverse depth feature initialization monocular SLAM (DI-D monocular SLAM), que pueda integrarse en un marco de SLAM colaborativo con interacción robot-humano. Con éste fin la investigación se ha centrado en dos áreas distintas. Primeramente la técnica DI-D SLAM ha sido estudiada y analizada, revisando sus procesos y algoritmos, con énfasis en el problema de asociación de datos. El estudio del problema de DA ha dado lugar a un nuevo algoritmo de validación para asociación de datos, que permite evitar información espuria y hacer al proceso más robusto. Una vez analizado y actualizado el método DI-D SLAM, se procede a introducir el marco de colaboración HRI, enfocándolo inicialmente en resolver uno de los inconvenientes del método de SLAM: el requisito de introducir parte del mapa a priori para mantener la estimación de la escala. Para introducir la colaboración HRI se emplea un dispositivo vestible que incorpora una cámara secundaria y otros sensores. La información de esta cámara secundaria, cuya pose con respecto a la cámara de SLAM principal es aproximadamente conocida, permite acelerar la introducción de características en el método DI-D SLAM y evitar el requisito de inicializar la escala del mapa. La introducción del método de percepción colaborativa permitido expandir sus beneficios a otras partes y problemas del método DI-D SLAM. Para ello se integró por completo en el proceso de medida y corrección del filtro de Kalman extendido (EKF) usado, tratando la medición colaborativa como un sensor virtual. Para poder evaluar cómo influye el comportamiento sistema HRI se derivaron varias métricas nuevas, que fueron estudiadas con una batería de secuencias experimentales.
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Wang, Wenyi. "Robust Chroma Keying System Based on Human Visual Perception and Statistical Color Models." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35271.
Full textAbstract:
In this thesis, we propose a chroma keying system that automatically estimates the
alpha map and the reliable intrinsic color of foreground objects in front of solid background. Our system is designed to be capable of distinguishing the transparent
foreground from the re flective foreground and shaded background, thereby making
the artifacts of the composited image less conspicuous. Speci cally, we assume that
the transparent region tends to be with higher saturation and lightness compared with region re ecting background light. With this assumption, a threshold function (TF) on a saturation-lightness plane is de ned according to human visual experiments. The pixels with color mixed with the background light (conventional unknown pixels) are now further categorized into re ective pixels and transparent pixels according to TF. In this case, the re ective and the transparent regions are separated to improve the alpha matte quality. Furthermore, a new color representation model is proposed to estimate the intrinsic color of each pixel according to the global color distribution of the image. The underlying assumption of our proposed model is that all colors in a natural image can be approximated by a limited number of chrominance values (dominant colors). Speci cally, the color statistics are counted by 2D histogram analysis. Then, we approximate the color distribution by the sum of a set of Gaussian mixture functions (GMF), whose centroids are the dominant colors (Dc) of the image. By choosing colors around each Dc, the possible intrinsic colors for each pixel can be comprehensively and e fficiently selected. Considering the fast development of IP-based video broadcasting, we present a data hiding scheme that can protect the chroma keying results when the image/video data is recorded in the JPEG/H.264 format. According to our simulation, the proposed chroma keying system generates high quality composited images that are little a ected by re ecting, background shading, and intrinsic color missing.
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Boulton, J. C. "Mechanisms involved in the encoding of image motion by the human visual system." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234967.
Full textAbstract:
The aim of this study is to investigate the processes that underlie image motion detection in human vision. To do this I have investigated motion perception for a wide range of stimulus velocities across the visual field, and have made use of different stimuli. Two mechanisms were revealed at different positions across the visual field as a result of the examination of the temporal properties of the Lower Threshold of Motion (LTM), that is, the lowest velocity that is reliably detected. The results for central vision showed that the LTM is mediated by a code that utilizes the spatial displacement transversed by the stimulus. For peripheral vision, the LTM is mediated by a code that utilizes the velocity or temporal frequency of the stimulus. This raised the question, do these two processes underlie image motion processing at all eccentricities with different sensitivities at threshold? To investigate this question, a wide velocity range was used to assess the ability of the visual system to discriminate different speeds. The temporal and spatial properties of the stimulus were individually disrupted to reveal the critical cues for velocity discrimination. The results show the presence of two processes at all eccentricities. The two processes can be characterised as a displacement code, and a velocity code. Evidence is shown that the velocity code uses 'velocity' information and not solely temporal frequency information. For central vision, the displacement code is most sensitive for short stimulus durations. The duration at which it is most sensitive is inversly proportional to the velocity of the stimulus. The velocity code is most sensitive at long term regions of the visual field. However, the range of velocities to which each mechanism is sensitive changes at different rates across the visual field. This leaves a range of low velocities which are detected only by the velocity mechanism at large eccentricities. Further investigation into the displacement code has revealed that this code can be characterised by an optimal displacement. This is less than the 1/4 of a spatial cycle of the stimulus which is proposed value for quadrature phase. Also luminance contrast was found to be an important parameter of the motion process. The two codes described above could be mediated by two motion areas of the primate visual cortex: the striate and prestriate cortex. From recent single cell studies, the emerging properties of neurons in these two parts of the visual cortex suggest that the displacement code may be mediated by the striate cortex, and the velocity code by the middle temporal area of the pre striate cortex.
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Cater, Kirsten Fiona. "Detail to attention : exploiting limits of the human visual system for selective rendering." Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404295.
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Isik, Leyla. "The dynamics of invariant object and action recognition in the human visual system." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/98000.
Full textAbstract:
Thesis: Ph. D., Massachusetts Institute of Technology, Computational and Systems Biology Program, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 123-138).
Humans can quickly and effortlessly recognize objects, and people and their actions from complex visual inputs. Despite the ease with which the human brain solves this problem, the underlying computational steps have remained enigmatic. What makes object and action recognition challenging are identity-preserving transformations that alter the visual appearance of objects and actions, such as changes in scale, position, and viewpoint. The majority of visual neuroscience studies examining visual recognition either use physiology recordings, which provide high spatiotemporal resolution data with limited brain coverage, or functional MRI, which provides high spatial resolution data from across the brain with limited temporal resolution. High temporal resolution data from across the brain is needed to break down and understand the computational steps underlying invariant visual recognition. In this thesis I use magenetoencephalography, machine learning, and computational modeling to study invariant visual recognition. I show that a temporal association learning rule for learning invariance in hierarchical visual systems is very robust to manipulations and visual disputations that happen during development (Chapter 2). I next show that object recognition occurs very quickly, with invariance to size and position developing in stages beginning around 100ms after stimulus onset (Chapter 3), and that action recognition occurs on a similarly fast time scale, 200 ms after video onset, with this early representation being invariant to changes in actor and viewpoint (Chapter 4). Finally, I show that the same hierarchical feedforward model can explain both the object and action recognition timing results, putting this timing data in the broader context of computer vision systems and models of the brain. This work sheds light on the computational mechanisms underlying invariant object and action recognition in the brain and demonstrates the importance of using high temporal resolution data to understand neural computations.
by Leyla Isik.
Ph. D.
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Gravano, S. "An experimental study of fine-grain motion perception in the human visual system." Thesis, Keele University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354931.
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Sanguinetti, Joseph LaCoste. "The Dynamics Of Perceptual Organization In The Human Visual System; Competition In Time." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/333347.
Full textAbstract:
The visual system receives a series of fluctuating light patterns on the retina, yet visual perception is strikingly different from this unorganized and ambiguous input. Thus visual processes must organize the input into coherent units, or objects, and segregate them from others. These processes, collectively called perceptual organization, are fundamental to our ability to perceive and interact with objects in the world. Nevertheless, they are not yet understood, perhaps because serial, hierarchical assumptions that were long held impeded progress. In a series of experiments, this dissertation investigated the mechanisms that contribute to perceptual organization and ultimately to our ability to perceive objects. A new hypothesis is that during the course of object assignment potential objects on either side of a border are accessed on a fast pass of processing and engage in inhibitory competition for object status; the winner is perceived as the object and the loser is suppressed, leading that region to be seen as part of the shapeless background. Previous research suggested that at least shape level representations are accessed on the fast pass of processing before object assignment. In the first series of experiments (Chapter 1), we found that meaning (semantics) is also accessed on the fast pass of processing for regions that are ultimately perceived as shapeless grounds. This finding contradicts traditional feed-forward theories of perception that assumed that meaning is accessed only for figures after object assignment. The experiments in Chapter 2 examine activity in the alpha band of the EEG, which has been used as an index of inhibition. More alpha activity was observed when participants viewed stimuli designed such that there was more competition for figural status from the region ultimately perceived as the ground. The results support the proposal that inhibitory competition occurs during the course of object perception, and these results are the first online measure of competition during figure assignment. The final series of experiments (Chapter 3) investigated how quickly saccadic behaviors that required perceptual organization can be initiated. The experiments show that participants can initiate saccades that are based on perceptual organization approximately 200 ms after stimulus onset, much faster than was assumed on feed-forward models of perception. Collectively, these experiment support models of object perception that involve the mutual interaction and competition of objects properties via feedforward and iterative feedback processing, and the eventual suppression of the losing ground regions before object assignment.
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Fitzhugh, N. P. "Low level and high level processes of motion detection in the human visual system." Thesis, University of Reading, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380679.
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Oh, Han, and Yookyung Kim. "Low-Complexity Perceptual JPEG2000 Encoder for Aerial Images." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595684.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, NevadaA highly compressed image inevitably has visible compression artifacts. To minimize these artifacts, many compression algorithms exploit the varying sensitivity of the human visual system (HVS) to different frequencies. However, this sensitivity has typically been measured at the near-threshold level where distortion is just noticeable. Thus, it is unclear that the same sensitivity applies at the supra-threshold level where distortion is highly visible. In this paper, we measure the sensitivity of the HVS for several supra-threshold distortion levels based on our JPEG2000 distortion model. Then, a low-complexity JPEG2000 encoder using the measured sensitivity is described. For aerial images, the proposed encoder significantly reduces encoding time while maintaining superior visual quality compared with a conventional JPEG2000 encoder.
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Salamat, Rana. "RichComment : Designing an Interactive Commenting System for Visual Content in Fashion Social Networks." Thesis, KTH, Medieteknik och interaktionsdesign, MID, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-232318.
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In this study, a new design of commenting system for visual contents is investigated. The aim is to explore the elements which enrich the user interaction and enhance the user experience while commenting, specifically on fashion social networks. This study explores how an improved commenting system may motivate fashion social networks’ users to express their idea about fashion products. A speculative design approach is used as a means for investigation. A design process consisting of semi structured interviews, thematic analysis, paper prototype, online prototype and user testing is followed to design a human-centered commenting system. The results suggest that providing richer tools for commenting could improve the user interaction. The most promising elements to use in fashion social media commenting system are color and pattern palettes, tagging comment and comment categorization. These elements enable fashion customers to express their ideas easier and obtain a holistic overview around other peoples’ comments. Apart from fashion brands’ social networks, the approach may also be more effective in fashion brand websites. People would like to have a strong impact on fashion brands. Therefore, commenting somewhere that is tightly connected to fashion brands are preferred rather than having the conversation just among themselves in social media.Detta projekt handlar om att undersöka och utforma ett nytt system för att kommentera visuellt innehåll. Mer specifikt är målet att utforska de element som berikar användarinteraktionen och förbättrar användarupplevelsen i kontexten av sociala nätverk och kommentarer kring klädmode. Detta projekt tittar på hur ett förbättrat kommentarsystem kan motivera användare på sociala nätverk att uttrycka sig i termer av egna idéer kring modeprodukter. Designprocessen för projektet består av semi-strukturerade intervjuer, tematisk analys, pappersprototyper, online-prototyper och användarstudier i syfte att designa ett mer användarcentrerat kommentarsystem. Resultaten pekar på att genom att tillhandahålla ett rikare verktyg för kommentarer så kan användarens interaktion och upplevelse förbättras. De delar av designen för att kommentera mode i sociala nätverk som är mest lovande är färg och mönsterpaletter, taggning av kommentarer samt kategorisering av kommentarer. Dessa delar gör det möjligt för potentiella kunder att på ett enkelt sätt uttrycka sina idéer och samtidigt få en överblick av andra människors kommentarer. Bortsett från modevarumärkenes sociala nätverk så kan tillvägagångssättet även appliceras på mode-bolagens egna webbplatser. I studien såg vi att användare önskar ha en starkare relation till dessa varumärken och mode-bolag. Av detta följer att det är viktigt att användare har möjlighet att på ett rikare sätt kommentera i den nära kontexten till mode-varumärken snarare än att ha konversationen i vanliga sociala medier.