Human factors in designing image-based virtual environment

Résumé du document

Virtual reality (VR) is an emerging technology and tends to be more and more widely developed. Virtual realities can be considered as a new form of simulation devices; a new way to represent reality in a sensible manner. They are defined firstly on the technology they use and on the other hand, on a conceptual plan. Indeed, virtual reality activates perceptual and cognitive mechanisms as well as concrete representations. VR technology may either be immersive or non-immersive. Immersive technology implies a display through a stereoscopic device i.e. a video helmet, while non- immersive VR is displayed via a personal computer's screen and three-dimensional graphics. This latter is called "desktop display". On a conceptual hand, VR is represented as a three-dimensional environment in which we can navigate, interact in real time, and that provides a feel of presence (Psotka, 1995). This study concerns factors, which influence the feel of reality within the field of virtual reality (VR). The study of reactions or inducted phenomena may lead us to better understand them and to contribute to their development. We are going to investigate which factors are contributing to this feel of reality when an interaction with a virtual environment is undertaken. In order to achieve this, we are going to study the influence of certain factors by comparing different image-based VR systems. In order to achieve it, we will expose several participants to three non-immersive systems (a video game, a VR representation of the Helsinki city centre and our deliverable) and rate their sense of presence. All these systems are able to give a feel of presence to their users. The effective measure of presence in each of those environments will lead us to understand this impression of reality which we may have or not have when using VR systems. Presence is defined as the subjective impression of being in a simulated environment (Slater and Usoh, 1993).

Extraits

[...] However, they require every displayable set/point of view to be shot and stored in the authoring stage i.e. the software used to build the 3D pictures. That method restricts freedom of movement and reduces the interaction between user and application. It limits movements to a few particular points. Moreover, in order to produce a high-quality environment with IBR, the engineer has to be careful while shooting the switching path, i.e. the point where the 12 user will want to switch from a branch to another. [...]

[...] Sec Second attempt: Time of completion: . Min . Sec 4. The 360-degrees panoramas walkthrough To be completed by the experimenter Does the participant have visited the environment? Yes No Observations: . APPENDIX Honours project Gantt chart Honours project Gantt Chart Week Special events Project events Tasks number RW CAB Easter AB PC IR PP 1 Literature review and research work IR Software review Design an experiment Implement the prototype Evaluation Dissertation Redaction PP prep. Extract results References Barfield, W., & Weghorst, S. (1993). [...]

[...] [accessed 05/2003] Lilavois, N. (2001). An introduction of VirtualReality. URL: http://www.magentalogic.com/book/vr.html [accessed 05/2003] ADAM Reference to Animated Dissection of Anatomy for Medicine, an interactive multimedia encyclopaedia of anatomy; ADAM software, Inc, Marietta, Georgia URL: http://www.adam.com/ [accessed 05/2003] McManus, E. (2000). The intuitive tool Human Computer Interaction. Essay submitted to Dublin City University School of Computer Applications for the course CA414: Multimedia Information Systems. URL: http://www.redbrick.dcu.ie/~eimhin/MMIS-essay.html [accessed 05/2003] Gateway support website (2003), Microsoft''s PC 97 initiative explained. Frequency asked questions section. [...]

[...] For instance, the control of blending is automated and not configurable by the user. The technical details of the software are described below General Version reviewed 2.0 Windows (version 1.01 is available for Platform(s) Mac) Free Download trial available from Availability www.mgisoft.com Image Stitching Panorama (single-row) Yes Panorama (multi-row) No Panorama (from panoramic No camera) Panorama (single shot) No Spherical panorama No Lens/source image types type(s) Fisheye and non-fisheye 15mm (wider focal lengths can be used if focal lengths creating a custom lens definition) Tilt up/down No, camera must remain level Roll left/right No Correct distortion No Output Cylindrical, Spherical (equirectangular), Image projection Cubic JPEG and BMP - an Image Worlds IVR file is also automatically generated Output File Formats includes all of cylindrical, spherical and cubic projection Create hotspots No (only allows creation of panorama) Table Technical details of MGI PhotoVista Panorama v2. [...]

[...] Participants were asked to evaluate the importance of the sound according to their feel to be present in the virtual environment. The average rate for this question reaches 5.3 /6. This result proves that sound is an essential factor of presence. Nevertheless, it must be underlined that the effect of the sound would have been deeper studied. Studies showed that without a sound environment, the level of presence is lower than in a sound atmosphere (Darken, Bernatovich, Lawson and Peterson, 1999). [...]