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Durham E-Theses Stereoscopic 3D Technologies for Accurate Depth Tasks: A Theoretical and Empirical Study FRONER, BARBARA How to cite: FRONER, BARBARA (2011) Stereoscopic 3D Technologies for Accurate Depth Tasks: A Theoretical and Empirical Study, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/3324/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk 2 Stereoscopic 3D Technologies for Accurate Depth Tasks: A Theoretical and Empirical Study by Barbara Froner A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy School of Engineering and Computing Sciences Durham University United Kingdom Copyright °c 2011 by Barbara Froner Abstract Stereoscopic 3D Technologies for Accurate Depth Tasks: A Theoretical and Empirical Study Barbara Froner In the last decade an increasing number of application ¯elds, including medicine, geoscience and bio-chemistry, have expressed a need to visualise and interact with data that are inherently three-dimensional. Stereoscopic 3D technologies can o®er a valid support for these operations thanks to the enhanced depth representation they can provide. However, there is still little understanding of how such technologies can be used e®ectively to support the performance of visual tasks based on accurate depth judgements. Existing studies do not provide a sound and complete explanation of the impact of di®erent visual and technical factors on depth perception in stereoscopic 3D environments. This thesis presents a new interpretative and contextualised analysis of the vision sci- ence literature to clarify the role of di®erent visual cues on human depth perception in such environments. The analysis identi¯es luminance contrast, spatial frequency, colour, blur, transparency and depth constancies as influential visual factors for depth perception and provides the theoretical foundation for guidelines to support the performance of accurate stereoscopic depth tasks. A novel assessment framework is proposed and used to conduct an empirical study to evaluate the performance of four distinct classes of 3D display technologies. The results suggest that 3D displays are not interchangeable and that the depth representation pro- vided can vary even between displays belonging to the same class. The study also shows that interleaved displays may su®er from a number of aliasing artifacts, which in turn may a®ect the amount of perceived depth. The outcomes of the analysis of the influential visual factors for depth perception and the empirical comparartive study are used to propose a novel universal 3D cursor prototype suitable to support depth-based tasks in stereoscopic 3D environments. The contribution includes a number of both qualitative and quantitative guidelines that aim to guarantee a correct perception of depth in stereoscopic 3D environments and that should be observed when designing a stereoscopic 3D cursor. ii Declaration The material contained within this thesis has not previously been submitted for a degree at Durham University or any other university. The research reported within this thesis has been conducted by the author unless indicated otherwise. This research has been documented, in part, within the following publications: ² B. Froner, N.S. Holliman and S.P. Liversedge. A comparative study of ¯ne depth perception on two-view 3D displays. Displays, 29(5):440-450, December 2008. ² N.S. Holliman, B. Froner and S.P. Liversedge. An application driven comparison of depth perception on desktop 3D displays. In Stereoscopic Displays and Virtual Reality Systems XIV, Proceedings of SPIE-IS&T Electronic Imaging, Volume 6490A, January 2007. Further relevant research conducted by the author has been documented in the following publications: ² N.S. Holliman, C. Baugh, C. Frenk, A. Jenkins, B. Froner, D. Hassaine, J. Helly, N. Metcalfe and T. Okamoto. Cosmic cookery: making a stereoscopic 3D animated movie. In Stereoscopic Displays and Virtual Reality Systems XVII, Proceedings of SPIE-IS&T Electronic Imaging, Volume 6055A, San Jose (CA-USA), January 2006. ² B. Froner and N.S. Holliman. Implementing an Improved Stereoscopic Camera Model, in Eurographics Theory and Practice of Computer Graphics 2005, Canter- bury (UK), June 2005. iii Copyright Notice The copyright of this thesis rests with the author. No quotation from it should be published without the author's prior written consent and information derived from it should be acknowledged. iv Acknowledgements I would like to express my gratitude to my academic supervisors Dr Nick Holliman and Prof Malcolm Munro, for providing me with the opportunity to pursue a PhD and for their advice and guidance during my research. A heartfelt thank you and love go to my husband Dr Nikolaos Galiatsatos for standing by me throughout these six years of part time studies and for putting up with my moods; I do not know how I would have been able to accomplish this without your continuous support, encouragement and patience. An equally heartfelt thanks goes to my parents Maria Grazia and Mario, for believing in me and supporting me throughout my entire education. Many thanks also to the rest of my family for their care and understanding. I am grateful to Prof Simon Liversedge, Dr Gustav Kuhn and Prof John Findley for their invaluable advice on statistics and perceptual psychology, and to Prof Luisa Mich for her encouragement and counsel. I also wish to thank my current employer, Foster Findley Associate, for their flexibility and for allowing me the time to complete my studies. Special thanks go to Dale Norton, Dr Oliver Vogt, Tamzin Cloke and Simon McConway for their excellent job in proof reading my draft and their suggestions, and to Dr James Lowell for the brilliant time we had when we were sharing the o±ce at uni. For their contribution to this work thanks also go to my research group members Dr Djamel Hassaine, Paul Gorley and Geng Sun. I would like to express a very special thank you to Stefano Pellegrini for his invaluable support and friendship, and for standing by me in di±cult times. Finally, I wish to thank Roberta Cristelli, Dr Adam Eckersley, Prof Keith Gallagher, Dr John Bailey, Dr Pim van 't Hof, Andrea Bonf¶aand all my other friends for their encouragement and continual belief. v Dedicated to my parents, Maria Grazia and Mario Hibiscus, Copyright °c by anaglyph (original title \Another flower, anaglyph", from anaglyph.deviantart.com) vi Contents 1 Introduction 1 1.1 Context of Work . 2 1.2 Statement of the Problem . 3 1.3 Aim and Objectives . 4 1.4 Thesis Overview and Research Contributions . 6 2 Depth Perception and Stereoscopic 3D Environments 9 2.1 Introduction . 9 2.2 Human Vision and Depth Perception . 10 2.2.1 Introduction . 10 2.2.2 Seeing in 3D . 10 2.2.3 Oculomotor Depth Cues . 11 2.2.4 Monocular Depth Cues . 14 2.2.5 Binocular Depth Cues and Stereopsis . 18 2.2.6 Depth Cues Integration . 20 2.3 Electronic 3D Display Systems . 21 2.3.1 Introduction to 3D Technologies . 21 2.3.2 Stereoscopic versus Autostereoscopic Systems . 22 2.3.3 3D Display Taxonomy . 22 vii CONTENTS viii Two-View Displays . 24 Multi-View Displays . 27 Volumetric Displays . 29 Others . 30 Summary . 31 2.3.4 Depth Perception on 3D Displays . 32 2.4 Depth-Based Tasks and Stereoscopic 3D Technologies . 34 2.4.1 Application Fields . 34 2.4.2 Previous Work on Stereoscopic 3D Cursors . 35 Medical Imaging . 36 Computer Graphics and 3D Aided Design . 36 Virtual Reality, Augmented Reality and Interaction Techniques . 41 Perception and Other Relevant Studies . 45 2.5 Conclusions . 47 3 Design of a Stereoscopic 3D Cursor 49 3.1 Introduction . 49 3.2 Visual Factors . 50 3.2.1 Luminance Contrast . 50 3.2.2 Spatial Frequency . 57 3.2.3 Colour . 61 3.2.4 Perspective, Distance and Depth Constancies . 70 3.2.5 Blur and Depth of Focus . 76 3.2.6 Occlusion and Transparency . 81 3.2.7 Summary of Visual Factors . 86 3.3 Technical Factors . 88 3.3.1 Display Resolution . 88 CONTENTS ix 3.3.2 Sampling and Aliasing Artifacts . 90 3.3.3 Image Interleaving . 91 3.3.4 Summary of Technical Factors . 92 3.4 Synthetic Cues . 93 3.5 General Discussion . 96 3.6 Conclusions . 98 4 Assessment of 3D Technologies: Methodology 100 4.1 Introduction . 100 4.2 Background . 101 4.3 Research Method . 103 4.3.1 Experimental Design . 103 4.3.2 Task and Stimuli . 104 4.3.3 Procedure . 107 4.4 Geometric Predictions . 108 4.4.1 Terminology and De¯nitions . 109 4.4.2 3D Display Classi¯cation . 110 4.4.3 Theoretical Predictions and Hypotheses . 111 4.5 Pilot Experiment . 115 4.5.1 Participants . 116 4.5.2 Experimental Conditions and Trial Blocks . 116 4.5.3 Apparatus . 117 4.5.4 Stimuli Details . 117 4.5.5 Results . 118 Score . 118 Response Time . 125 Subjective Results . 134 CONTENTS x 4.6 Conclusions . 137 5 Assessment of 3D Technologies: Results 139 5.1 Introduction . 139 5.2 Experimental Details .
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