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University of Plymouth PEARL https://pearl.plymouth.ac.uk 04 University of Plymouth Research Theses 01 Research Theses Main Collection 2012 CHROMO-STEREOSCOPIC VISUALISATION FOR DYNAMIC MARINE OPERATIONS ABDEL HAMID, IMAN http://hdl.handle.net/10026.1/1240 University of Plymouth All content in PEARL is protected by copyright law. Author manuscripts are made available in accordance with publisher policies. Please cite only the published version using the details provided on the item record or document. In the absence of an open licence (e.g. Creative Commons), permissions for further reuse of content should be sought from the publisher or author. CHROMO-STEREOSCOPIC VISUALISATION FOR DYNAMIC MARINE OPERATIONS by IMAN ABDEL HAMID A thesis submitted to the University of Plymouth in partial fulfilment for the degree of DOCTOR OF PHILOSOPHY School of Marine Sciences & Engineering Faculty of Science & Technology October 2012 Copyright Statement This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise, that its copyright rests with the author, and that no quotation from the thesis, and no information derived from it may be published without the author’s prior consent. Signed: …Iman……………… Iman Abdel Hamid Date: …. 28 October 2012..… 2 Abstract Chromo-Stereoscopic Visualisation in Dynamic Marine Operations Iman Abdel Hamid Chromo-Stereoscopy (CS) is a simple and cost effective 3D system that can easily deliver geospatial information. CS has been used in several scientific data presentations, including remote sensing, physical modelling and hydrographic applications. In some of these applications the 3D effect was solely CS-related, while others integrated CS with other methods of implementing 3D. CS has been mainly used in static visualisation, but no dynamic applications were found. Also, the restricted use of colour was acknowledged as a limitation for CS suggesting its unsuitability for applications where colour conventions are significant. This research focuses on CS for marine applications and aims to: (i) investigate user’s perception to CS effect and its interaction with other depth cues, (ii) assess the acceptance of the potential users to the changes in conventional colouring systems, and (iii) evaluate the usability and practicality of CS as an additional visualisation system in dynamic marine applications. To address these, visual scenarios were developed and expert human participants were recruited and interviewed for the evaluation. CS was well perceived among the participants. The interaction between different depth cues has advantages of increasing the depth perception and comprehending the 3D nature of the surrounding environment. For instance, from a certain view angle where two objects block each other, CS enhances the interposition effect, that indicates which object is in the front and gives a qualitative estimation of the spatial separation between them. Shading increases the realism of surface objects, and provides information for their undulation. It also dilutes the colours used in CS and increases the range of colours perceived and enhances the effect perceived from CS. The advantage of using the colour coding system to indicate distance is a valuable and original outcome of this thesis. This coding improved the participants understanding of the behaviour of moving objects (whether vessels coming closer or drifting apart) and enabled users to locate them in reference to the surrounding topography. Such knowledge is important to attain safer operations in a 3D environment. Accepting changes in colours in a visual presentation is linked to experience gained during interaction with the system, and the changes would be tolerated by the users in favour of improvements in situation awareness. Blind navigation and underwater operations are examples of where CS can be beneficial. 3 Table of Contents Copyright Statement ................................................................................. 1 Abstract ...................................................................................................... 3 List of Figures .......................................................................................... 10 List of Tables ........................................................................................... 16 Acknowledgments ................................................................................... 17 Author’s declaration................................................................................ 18 List of Abbreviations ............................................................................... 19 Chapter One ............................................................................................. 21 1 Introduction ....................................................................................... 21 1.1 Aim and objectives of the research .................................................. 22 1.1.1 Aim ............................................................................................................22 1.1.2 Objectives ..................................................................................................22 1.2 Thesis overview ................................................................................. 23 1.3 Conferences and workshops ............................................................ 25 Chapter Two ............................................................................................. 27 2 3D Vision and Visualisation ............................................................. 27 2.1 Human vision: Seeing in 3D .............................................................. 28 2.1.1 Oculomotor cues ........................................................................................28 2.1.1.1 Occlusion .............................................................................................29 2.1.1.2 Linear perspective ................................................................................30 2.1.1.3 Aerial perspective .................................................................................30 2.1.1.4 Detail perspective/ texture gradient .......................................................31 2.1.1.5 Relative size and familiar size ...............................................................31 2.1.1.6 Lighting and shadow.............................................................................31 2.1.1.7 Relative brightness ...............................................................................32 2.1.1.8 Relative height or plane height .............................................................32 2.1.2 Motion cues ...............................................................................................32 2.1.3 Chromatic aberration ..................................................................................33 2.1.4 Binocular cues ...........................................................................................33 2.2 Effectiveness of depth cues.............................................................. 34 4 2.3 Colour vision ...................................................................................... 35 2.3.1 Individual Colour Perception .......................................................................38 2.4 3D cartography & 3D display systems ............................................. 38 2.4.1 Stereoscopic displays ................................................................................39 2.4.1.1 Stereoscopes .......................................................................................40 2.4.1.2 Anaglyph techniques ............................................................................40 2.4.1.3 Polarized displays ................................................................................41 2.4.1.4 Chromo-Stereoscopy (CS) ...................................................................43 2.4.1.5 ChromaDepth glasses ..........................................................................43 2.4.1.6 Chromo-stereoscopic images ...............................................................44 2.4.2 Field/ Frame sequential displays: active and passive glasses .....................45 2.4.3 Shutter glasses ..........................................................................................45 2.4.4 Virtual Reality (VR).....................................................................................46 2.4.4.1 Cave Automatic Virtual Environment (CAVE) ........................................46 2.4.4.2 Head Mounted Displays (HMDs) ...........................................................47 2.4.5 Autostereoscopic systems ..........................................................................47 2.4.5.1 Parallax stereograms............................................................................48 2.4.5.2 Lenticular sheets ..................................................................................49 2.4.5.3 Holography ...........................................................................................49 2.4.5.4 Volumetric displays ..............................................................................50 2.5 Chapter summary .............................................................................. 50 Chapter Three .......................................................................................... 52 3 Data presentation in marine field .................................................... 52 3.1 Nautical charts ..................................................................................
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