Zoetrope Blues

Zoetrope Blues surveys the zoetrope style of animation from its inception to its contemporary practitioners, discussing both the unique charms of the medium and the technical elements that make it work. This paper delineates the process behind zoetrope creation while also investigating the effects made possible by modern technology. The zoetrope was the world’s first motion picture format, using the flicker of a handheld carousel to transform a spinning disc into the illusion of a moving image. This Victorian parlor trick changed our understanding of vision and laid the foundation for cinema, but was largely forgotten with the invention of the film projector. Despite being a “dead medium,” the zoetrope has seen recent applications as varied as turntablism, sculpture, and augmented reality. Its quirks give it a careworn aesthetic which stands out against the glossy sheen of digital design, and its mandala-like polar grid gives it a psychedelic edge

A virtual environment system for spatial orientation research

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.Includes bibliographical references (leaves 74-75).by John de Souza.M.S

Sensor Fusion in the Perception of Self-Motion

This dissertation has been written at the Max Planck Institute for Biological Cybernetics (Max-Planck-Institut für Biologische Kybernetik) in Tübingen in the department of Prof. Dr. Heinrich H. Bülthoff. The work has universitary support by Prof. Dr. Günther Palm (University of Ulm, Abteilung Neuroinformatik). Main evaluators are Prof. Dr. Günther Palm, Prof. Dr. Wolfgang Becker (University of Ulm, Sektion Neurophysiologie) and Prof. Dr. Heinrich Bülthoff.amp;lt;bramp;gt;amp;lt;bramp;gt; The goal of this thesis was to investigate the integration of different sensory modalities in the perception of self-motion, by using psychophysical methods. Experiments with healthy human participants were to be designed for and performed in the Motion Lab, which is equipped with a simulator platform and projection screen. Results from psychophysical experiments should be used to refine models of the multisensory integration process, with an mphasis on Bayesian (maximum likelihood) integration mechanisms.amp;lt;bramp;gt;amp;lt;bramp;gt; To put the psychophysical experiments into the larger framework of research on multisensory integration in the brain, results of neuroanatomical and neurophysiological experiments on multisensory integration are also reviewed

Change blindness: eradication of gestalt strategies

Arrays of eight, texture-defined rectangles were used as stimuli in a one-shot change blindness (CB) task where there was a 50% chance that one rectangle would change orientation between two successive presentations separated by an interval. CB was eliminated by cueing the target rectangle in the first stimulus, reduced by cueing in the interval and unaffected by cueing in the second presentation. This supports the idea that a representation was formed that persisted through the interval before being 'overwritten' by the second presentation (Landman et al, 2003 Vision Research 43149–164]. Another possibility is that participants used some kind of grouping or Gestalt strategy. To test this we changed the spatial position of the rectangles in the second presentation by shifting them along imaginary spokes (by ±1 degree) emanating from the central fixation point. There was no significant difference seen in performance between this and the standard task [F(1,4)=2.565, p=0.185]. This may suggest two things: (i) Gestalt grouping is not used as a strategy in these tasks, and (ii) it gives further weight to the argument that objects may be stored and retrieved from a pre-attentional store during this task

Phenomenal regression as a potential metric of veridical perception in virtual environments

It is known that limitations of the visual presentation and sense of presence in a virtual environment (VE) can result in deficits of spatial perception such as the documented depth compression phenomena. Investigating size and distance percepts in a VE is an active area of research, where different groups have measured the deficit by employing skill-based tasks such as walking, throwing or simply judging sizes and distances. A psychological trait called phenomenal regression (PR), first identified in the 1930s by Thouless, offers a measure that does not rely on either judgement or skill. PR describes a systematic error made by subjects when asked to match the perspective projections of two stimuli displayed at different distances. Thouless’ work found that this error is not mediated by a subject’s prior knowledge of its existence, nor can it be consciously manipulated, since it measures an individual’s innate reaction to visual stimuli. Furthermore he demonstrated that, in the real world, PR is affected by the depth cues available for viewing a scene. When applied in a VE, PR therefore potentially offers a direct measure of perceptual veracity that is independent of participants’ skill in judging size or distance. Experimental work has been conducted and a statistically significant correlation of individuals’ measured PR values (their ‘Thouless ratio’, or TR) between virtual and physical stimuli was found. A further experiment manipulated focal depth to mitigate the mismatch that occurs between accommodation and vergence cues in a VE. The resulting statistically significant effect on TR demonstrates that it is sensitive to changes in viewing conditions in a VE. Both experiments demonstrate key properties of PR that contribute to establishing it as a robust indicator of VE quality. The first property is that TR exhibits temporal stability during the period of testing and the second is that it differs between individuals. This is advantageous as it yields empirical values that can be investigated using regression analysis. This work contributes to VE domains in which it is desirable to replicate an accurate perception of space, such as training and telepresence, where PR would be a useful tool for comparing subjective experience between a VE and the real world, or between different VEs

A Framework for Dynamic Terrain with Application in Off-road Ground Vehicle Simulations

The dissertation develops a framework for the visualization of dynamic terrains for use in interactive real-time 3D systems. Terrain visualization techniques may be classified as either static or dynamic. Static terrain solutions simulate rigid surface types exclusively; whereas dynamic solutions can also represent non-rigid surfaces. Systems that employ a static terrain approach lack realism due to their rigid nature. Disregarding the accurate representation of terrain surface interaction is rationalized because of the inherent difficulties associated with providing runtime dynamism. Nonetheless, dynamic terrain systems are a more correct solution because they allow the terrain database to be modified at run-time for the purpose of deforming the surface. Many established techniques in terrain visualization rely on invalid assumptions and weak computational models that hinder the use of dynamic terrain. Moreover, many existing techniques do not exploit the capabilities offered by current computer hardware. In this research, we present a component framework for terrain visualization that is useful in research, entertainment, and simulation systems. In addition, we present a novel method for deforming the terrain that can be used in real-time, interactive systems. The development of a component framework unifies disparate works under a single architecture. The high-level nature of the framework makes it flexible and adaptable for developing a variety of systems, independent of the static or dynamic nature of the solution. Currently, there are only a handful of documented deformation techniques and, in particular, none make explicit use of graphics hardware. The approach developed by this research offloads extra work to the graphics processing unit; in an effort to alleviate the overhead associated with deforming the terrain. Off-road ground vehicle simulation is used as an application domain to demonstrate the practical nature of the framework and the deformation technique. In order to realistically simulate terrain surface interactivity with the vehicle, the solution balances visual fidelity and speed. Accurately depicting terrain surface interactivity in off-road ground vehicle simulations improves visual realism; thereby, increasing the significance and worth of the application. Systems in academia, government, and commercial institutes can make use of the research findings to achieve the real-time display of interactive terrain surfaces

Reflecting on pictorial spaces: an investigation into ambiguous spatial effects created through the use of reflective materials, fragmented abstract form and oblique linear structures.

This practice-led art research project investigates the relationships between geometric abstract painting, architecture and urban space. The outcome of the research is an exhibition of large-scale and medium sized geometric abstract paintings on canvas that explore issues of reflection and spatial deformation. Compositions drawing from the spatialities of contemporary architecture and urban space are examined through the use of reflective materials, fragmented abstract form and irregular structuring to create a range of spatial interpretations intended to engage and manipulate the viewer’s perceptions of illusory space. The project focuses on the inventive uses of reflective painting materials and recently developed synthetic colours influenced by digital technologies and high-gloss surface qualities. Innovative possibilities and opportunities in contemporary abstract painting practice are investigated through the use of newly developed commercial paint materials, pigments and mediums to create new perceptual and physiological experiences for the viewer. From the position of being a contemporary abstract painter I investigate key issues of spatial unease, disorientation and instability experienced in contemporary architecture and urban space, in order to produce highly ambiguous pictorial spatial experiences in my work, including infinite reflections, permutations and deformations. This project contributes original research to the field of abstract painting, and produces a new body of knowledge about pictorial spatial structures, colours and surface effects that generate disorientating viewing experiences and build on the relationship between abstract painting, architecture and urban space

Video based reconstruction system for mixed reality environments supporting contextualised non-verbal communication and its study

This Thesis presents a system to capture, reconstruct and render the three-dimensional form of people and objects of interest in such detail that the spatial and visual aspects of non-verbal behaviour can be communicated.The system supports live distribution and simultaneous rendering in multiple locations enabling the apparent teleportation of people and objects. Additionally, the system allows for the recording of live sessions and their playback in natural time with free-viewpoint.It utilises components of a video based reconstruction and a distributed video implementation to create an end-to-end system that can operate in real-time and on commodity hardware.The research addresses the specific challenges of spatial and colour calibration, segmentation and overall system architecture to overcome technical barriers, the requirement of domain specific knowledge to setup and generate avatars to a consistent high quality.Applications of the system include, but are not limited to, telepresence, where the computer generated avatars used in Immersive Collaborative Virtual Environments can be replaced with ones that are faithful of the people they represent and supporting researchers in their study of human communication such as gaze, inter-personal distance and facial expression.The system has been adopted in other research projects and is integrated with a mixed reality application where, during a live linkup, a three-dimensional avatar is streamed to multiple end-points across different countries