37 research outputs found
Quality-controlled audio-visual depth in stereoscopic 3D media
BACKGROUND: The literature proposes several algorithms that produce âquality-controlledâ stereoscopic depth in 3D films by limiting the stereoscopic depth to a defined depth budget. Like stereoscopic displays, spatial sound systems provide the listener with enhanced (auditory) depth cues, and are now commercially available in multiple forms.
AIM: We investigate the implications of introducing auditory depth cues to quality-controlled 3D media, by asking: âIs it important to quality-control audio-visual depth by considering audio-visual interactions, when integrating stereoscopic display and spatial sound systems?â
MOTIVATION: There are several reports in literature of such
âaudio-visual interactionsâ, in which visual and auditory perception influence each other. We seek to answer our research question by investigating whether these audio-visual interactions could extend the depth budget used in quality-controlled 3D media.
METHOD/CONCLUSIONS: The related literature is reviewed before presenting four novel experiments that build upon each otherâs conclusions. In the first experiment, we show that content created with a stereoscopic depth budget creates measurable positive changes in audiencesâ attitude towards 3D films. These changes are repeatable for different locations, displays and content. In the second experiment we calibrate an audio-visual display system and use it to measure the minimum audible depth difference. Our data is used to formulate recommendations for content designers and systems engineers. These recommendations include the design of an auditory depth perception screening test. We then show that an auditory-visual stimulus with a nearer auditory depth is perceived as nearer. We measure the impact of this effect upon a relative depth judgement, and investigate how the impact varies with audio-visual depth separation. Finally, the size of the cross-modal bias in depth is measured, from which we conclude that sound does have the potential to extend the depth budget by a small, but perceivable, amount
Perceived Acceleration in Stereoscopic Animation
In stereoscopic media, a sensation of depth is produced through the differences of images presented to the left and the right eyes. These differences are a result of binocular parallax caused by the separation of the cameras used to capture the scene. Creators of stereoscopic media face the challenge of producing compelling depth while restricting the amount of parallax to a comfortable range. Control of camera separation is a key manipulation to control parallax. Sometimes, stereoscopic warping is used in post-production process to selectively increase or decrease depth in certain regions of the image. However, mismatches between camera geometry and natural stereoscopic geometry can theoretically produce nonlinear distortions of perceived space. The relative expansion or compression of the stereoscopic space, in theory, should affect the perceived acceleration of objects moving through that space. This thesis suggests that viewers are tolerant of effects of distortions when perceiving acceleration in a stereoscopic scene
Human factors in the perception of stereoscopic images
Research into stereoscopic displays is largely divided into how stereo 3D content looks, a field concerned with distortion, and how such content feels to the viewer, that is, comfort. However, seldom are these measures presented simultaneously. Both comfortable displays with unacceptable 3D and uncomfortable displays with great 3D are undesirable. These two scenarios can render conclusions based on research into these measures both moot and impractical. Furthermore, there is a consensus that more disparity correlates directly with greater viewer discomfort. These experiments, and the dissertation thereof, challenge this notion and argue for a more nuanced argument related to acquisition factors such as interaxial distance (IA) and post processing in the form of horizontal image translation (HIT). Indeed, this research seeks to measure tolerance limits for viewing comfort and perceptual distortions across different camera separations. In the experiments, HIT and IA were altered together. Following Banks et al. (2009), our stimuli were simple stereoscopic hinges, and we measured the perceived angle as a function of camera separation. We compared the predictions based on a ray-tracing model with the perceived 3D shape obtained psychophysically. Participants were asked to judge the angles of 250 hinges at different camera separations (IA and HIT remained linked across a 20 to 100mm range, but the angles ranged between 50° and 130°). In turn, comfort data was obtained using a five-point Likert scale for each trial. Stimuli were presented in orthoscopic conditions with screen and observer field of view (FOV) matched at 45°. The 3D hinge and experimental parameters were run across three distinct series of experiments. The first series involved replicating a typical laboratory scenario where screen position was unchanged (Experiment I), the other presenting scenarios representative of real-world applications for a single viewer (Experiments II, III, and IV), and the last presenting real-world applications for multiple viewers (Experiment V). While the laboratory scenario revealed greatest viewer comfort occurred when a virtual hinge was placed on the screen plane, the single-viewer experiment revealed into-the-screen stereo stimuli was judged flatter while out-of-screen content was perceived more veridically. The multi-viewer scenario revealed a marked decline in comfort for off-axis viewing, but no commensurate effect on distortion; importantly, hinge angles were judged as being the same regardless of off-axis viewing for angles of up to 45. More specifically, the main results are as follows. 1) Increased viewing distance enhances viewer comfort for stereoscopic perception. 2) The amount of disparity present was not correlated with comfort. Comfort is not correlated with angular distortion. 3) Distortion is affected by hinge placement on-screen. There is only a significant effect on comfort when the Camera Separation is at 60mm. 4) A perceptual bias between into the depth orientation of the screen stimuli, in to the screen stimuli were judged as flatter than out of the screen stimuli. 5) Perceived distortion not being affected by oblique viewing. Oblique viewing does not affect perceived comfort. In conclusion, the laboratory experiment highlights the limitations of extrapolating a controlled empirical stimulus into a less controlled âreal worldâ environment. The typical usage scenarios consistently reveal no correlation between the amount of screen disparity (parallax) in the stimulus and the comfort rating. The final usage scenario reveals a perceptual constancy in off-axis viewer conditions for angles of up to 45, which, as reported, is not reflected by a typical ray-tracing model. Stereoscopic presentation with non-orthoscopic HIT may give comfortable 3D. However, there is good reason to believe that this 3D is not being perceived veridically. Comfortable 3D is often incorrectly converged due to the differences between distances specified by disparity and monocular cues. This conflict between monocular and stereo cues in the presentation of S3D content leads to loss of veridicality i.e. a perception of flatness. Therefore, correct HIT is recommended as the starting point for creating realistic and comfortable 3D, and this factor is shown by data to be far more important than limiting screen disparity (i.e. parallax). Based on these findings, this study proposes a predictive model of stereoscopic space for 3D content generators who require flexibility in acquisition parameters. This is important as there is no data for viewing conditions where the acquisition parameters are changed
Spatial and human factors affecting image quality and viewer experience of stereoscopic 3D in television and cinema
PhD ThesisThe horizontal offset in the two eyesâ locations in the skull means that they receive slightly different images of the world. The visual cortex uses these disparities to calculate where in depth different objects are, absolutely (physical distance from the viewer, perceived very imprecisely) and relatively (whether one object is in front of another, perceived with great precision). For well over a century, stereoscopic 3D (S3D) technology has existed which can generate an artificial sense of depth by displaying images with slight disparities to the different retinas. S3D technology is now considerably cheaper to access in the home, but remains a niche market, partly reflecting problems with viewer experience and enjoyment of S3D. This thesis considers some of the factors that could affect viewer experience of S3D content. While S3D technology can give a vivid depth percept, it can also lead to distortions in perceived size and shape, particularly if content is viewed at the wrong distance or angle. Almost all S3D content is designed for a viewing angle perpendicular to the screen, and with a recommended viewing distance, but little is known about the viewing distance typically used for S3D, or the effect of viewing angle. Accordingly, Chapter 2 of this thesis reports a survey of members of the British public. Chapters 3 and 4 report two experiments, one designed to assess the effect of oblique viewing, and another to consider the interaction between S3D and perceived size. S3D content is expensive to generate, hence producers sometimes âfakeâ 3D by shifting 2D content behind the screen plane. Chapter 5 investigates viewer experience with this fake 3D, and finds it is not a viable substitute for genuine S3D while also examining whether viewers fixate on different image features when video content is viewed in S3D, as compared to 2D.part-funded by BSkyB and EPSRC as a CASE PhD studentship supporting PH
Depth, shading, and stylization in stereoscopic cinematography
Due to the constantly increasing focus of the entertainment industry on stereoscopic imaging, techniques and tools that enable precise control over the depth impression and help to overcome limitations of the current stereoscopic hardware are gaining in importance. In this dissertation, we address selected problems encountered during stereoscopic content production, with a particular focus on stereoscopic cinema. First, we consider abrupt changes of depth, such as those induced by cuts in films. We derive a model predicting the time the visual system needs to adapt to such changes and propose how to employ this model for film cut optimization. Second, we tackle the issue of discrepancies between the two views of a stereoscopic image due to view-dependent shading of glossy materials. The suggested solution eliminates discomfort caused by non-matching specular highlights while preserving the perception of gloss. Last, we deal with the problem of filmgrainmanagement in stereoscopic productions and propose a new method for film grain application that reconciles visual comfort with the idea of medium-scene separation.Aufgrund der stĂ€ndig steigenden Beachtung der stereoskopische Abbildung durch die Unterhaltungsindustrie, gewinnen Techniken und Werkzeuge an Bedeutung, die eine prĂ€zise Steuerung der Tiefenwahrnehmung ermöglichen und EinschrĂ€nkungen der gegenwĂ€rtigen stereoskopischen GerĂ€te ĂŒberwinden. In dieser Dissertation adressieren wir ausgewĂ€hlte Probleme, die wĂ€hrend der Erzeugung von stereoskopischen Inhalten auftreten, mit besonderem Schwerpunkt auf der stereoskopischen Kinematographie. Zuerst betrachten wir abrupte TiefenĂ€nderungen, wie sie durch Filmschnitte hervergerufen werden. Wir leiten ein Modell her, das die Zeit vorhersagt, die fĂŒr das menschliche Sehsystem notwendig ist, um sich an solche Ănderungen der Tiefe zu adaptieren, und schlagen vor wie dieses Modell fĂŒr Schnittoptimierung angewendet werden kann. Danach gehen wir das Problem der Unstimmigkeiten zwischen den zwei Ansichten eines stereoskopischen Bildes, infolge der sichtabhĂ€ngigen Schattierung von glĂ€nzenden Materialien, an. Die vorgeschlagene Lösung eliminiert das visuelle Unbehagen, welches von nicht zusammenpassenden Glanzlichtern verursacht wird, indessen bewahrt sie die Glanzwahrnehmung. Zuletzt behandeln wir das Problem des Filmkornsmanagements in stereoskopischen Produktionen und schlagen eine neue Methode fĂŒr das HinzufĂŒgen vom Filmkorn vor, die die visuelle Behaglichkeit mit der Idee der Medium-Szenen-Trennung in Einklang bringt
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 43149â164]. 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
Animating Community: Reflexivity and Identity in Indian Animation Production Culture
Animating Community examines the cultural practices of animators in India, and particularly the role of practitioner testimony in conceiving and negotiating social structures underpinning the nascent Indian animation industry. Recognizing a tendency in practitioner accounts towards theorization of contested industrial discourses, this research takes as its object the reflexive practice of animators in trade texts and interviews. These reveal how local practitioners understand production culture as an emergent phenomenon, resulting from learned processes of negotiation and collective action. However, practitioner testimony also reflects dramatically different degrees of agency in cultural production and discourse. Focusing on the identity work of diverse creative professionals â corporate elites, freelancers, teachers, and students â reveals underlying tensions between global industrial constraints and local social capital.
Based on discursive analysis of testimony, this thesis asks how Indian animation practitioners conceive of their creative activity and identity in relation to negotiating a culture of animation production, and how the shared discourses and modes of engagement that result both shape and are shaped by institutional structures. These questions are addressed through practitioner accounts in three sectors of Indian animation: first, the context of production â considering large outsourcing firms and smaller studios; second, the provision of education â instruction in skills and social norms supplied by the public and private sectors; and third, the creation of dedicated community structures â professional organizations and trade information networks. Animating Community is most interested in how local media professionals articulate different discourses from aesthetic to economic value in order to approach an imagined sense of cultural identity. This sheds light on the way practitioners make sense of their creative and professional worlds. Ultimately, the conclusions offered in this project argue for a more nuanced conception of the relationship between critical practice and creative labour, and greater understanding of the different contexts where this may emerge
The Animator: The 26th Society for Animation Studies Annual Conference Toronto June 16 to 19, 2014
The 2014 Society for Animation Studies conference hosted by Sheridan College was from June 16 - 19, 2014. As Animation Studies continues to develop as a discipline, the dialogue that has opened up between more traditional academic research into the field and what we might call âindustry-facingâ or applied research has become more important. The critical study of animation from within higher education institutions like Sheridan represents one of the many areas in which the industry can grow. Every SAS conference has its own distinct tone and flavour because we are truly international in our membership and we devolve conference organization annually to the host institution. This means that this yearâs conference is strongly allied to Sheridanâs industry focus â not least with Corus warmly welcoming conference goers to their HQ for parts of the conference.
SAS provides such a welcoming environment for new members, and a terrific forum to discuss animation from a multitude of perspectives. It is within this fertile and nurturing atmosphere that we decided to focus our conference on the animation artist. As a tribute to all artists whose efforts fuel our work, and in the spirit of the centenary of celebrated National Film Board of Canada animator, Norman McLaren, the 2014 SAS Conference is named âThe Animatorâ.
Keynote speakers included Scott Dyer, Executive Vice President, Strategic Planning and Chief Technology Officer, Corus Entertainment Charile Bonifacio, Animator, Arc Productions Ltd, Canada Professor Paul Wells, Director of the Animation Academy Loughborough University, UK Michael Fukushima, Executive Producer of NFBâs English Animation Studio National Film Board of Canada
Panel Discussions McLaren Legacy Panel: The Centenary Year - Nichola Dobson, Terence Dobson, Kaj Pindal Stop Motion, From Local Community Members - Chris Walsh, Bret Long, Nora Keely, Mark Mayerson
Conference Twitter account: @AnimatorSAS2014https://source.sheridancollege.ca/conferences_anim/1000/thumbnail.jp