This volume of SPIE/IS&T proceedings "Stereoscopic Displays and Virtual Reality Systems VIII" comprises the papers from the two complimentary conferences "Stereoscopic Displays and Applications XII" and "The Engineering Reality of Virtual Reality VIII". In this introduction we take the opportunity to summarize the two conferences that were held at the IS&T/SPIE Electronic Imaging 2001 / Photonics West 2001 Symposium in San Jose, California, and summarize some of the activities of the conference committee over the past year.

This year's Stereoscopic Displays and Applications (SD&A) conference was held over the period 22-24 January 2001 and combined technical sessions with complementary activities such as the demonstration session, keynote presentation, standards forum, 3D video screening evening, and the author/attendee dinner. The conference is the culmination of a year's work on behalf of the authors and the committee and it is very pleasing to see so many stereoscopic imaging professionals, researchers, enthusiasts, and students brought together at one meeting for the purpose of information exchange, deal making, social exchange, etc. The conference continues to track recent developments in the field, announcing major breakthroughs right through to minor developments, and generally exploring the field.

The first day of the conference started with a session on "Stereoscopic Projection" chaired by Andrew Woods. All three papers explored ways in which the efficiency, brightness and extinction ratio of stereoscopically projected images could be improved.

The second session, "Human Factors in Stereoscopic Imaging", was chaired by John Merritt. The five papers in this session discussed the following topics: the potential benefit of stereo viewing in the underwater environment, the perception of ghosting in autostereoscopic displays, exploring the optimum amount of stereoscopic image overlap for teleoperation, the use of human factors to decide optimum camera parameters, and the perception of sampling artifacts in stereoscopic displays.

The most popular session of the day was "Stereoscopic Camera Systems" chaired by Neil Dodgson. Two particular papers in this session had the audience actively reaching for their 3D glasses. Don Snyder's paper discussed the US Air Force's new high-speed digital stereoscopic camera and some breathtaking images from this system were shown. On the other end of the camera complexity scale, Shmuel Peleg's paper on 3D panoramas, discussed and then demonstrated the use of a small monoscopic "webcam" to capture a 3D panorama of the conference audience. Other topics discussed included: experiments to determine the optimum image update rate for stereoscopic video cameras in teleoperation, the development of a computer controlled stereoscopic camera platform and its use for human factors experiments, and the development of a panoramic stereoscopic camera head.

The final technical session of the day was "Computer-Based Stereoscopic Imaging and Applications" chaired by Andrew Woods. The five papers in the session discussed various stereoscopic computer-based tools and applications including the Winx3D API which allows software developers to easily add stereoscopic display support to their programs and a range of programs which test and diagnose stereoscopic vision.

The evening 3D Video screening session again proved to be a very popular event at this year's conference. The session is a chance to showcase work that is being performed in 3D Video worldwide and this year's session had a very wide representation. 3D Videos shown included:

• "The DDD Spot" from Dynamic Digital Depth of Perth, Australia and Santa Monica, California.
• "Intel Delivers", a promotional piece for the Intel Xeon processor, produced by Delphi Productions in Alameda, California.
• "Blazer in the Third Dimension", a home fire safety video for school children from Media Odyssey in Brisbane, Australia
• "The Pearl Sea", a drama about a Korean pearl diving family, produced for Korea Trade-Investment Promotion Agency (KOTRA) and originally filmed in HiVision 3D by NHK Technical Services (Tokyo, Japan).
• "The World of Kapo the Clown", a CGI roller-coaster ride with a difference, from EjeZeta in Madrid, Spain.
• "Not Your Average Ski Movie" by Ray3D (Carbondale, Colorado).

The evening was topped off with a pleasant meal and discussion with many conference participants at a local San Jose restaurant. And it's rumored that Lenny Lipton told the real story behind Puff the Magic Dragon.

The second day of the conference started with our usual marathon session on "Autostereoscopic Displays", chaired in the morning by Stephen Benton and in the afternoon by Shojiro Nagata. Topics discussed included parallax barrier displays, head/eye-tracking systems, exit-pupil projection systems, volumetric displays, super multi-view displays, integral photography based autostereoscopic displays, and various new developments.

The final session for the day was "Recommendations and Standards for Stereoscopic Imaging". The session started with three papers of which a recurring theme was the play of human factors in determining appropriate recommendations and standards. The session continued with a panel session to discuss further the setting of standards of relevance to the stereoscopic imaging community. The session was chaired by Mike Weissman, with panel members Andrew Woods and Dave Swift (VREX), along with good input from the floor. The panel session is discussed in more detail in the separate report by Mike Weissman.

The final day of the Stereoscopic Displays and Applications conference started with a session on "Stereoscopic Image Processing and Compression" chaired by Neil Dodgson. The five papers in this session addresses topics such as the transmission of stereoscopic video over broadband and limited bandwidth networks, aspects specific to the compression of multi-view images and stereoscopic video, and the effects of geometrically processing stereoscopic images.

The next session was an experimental "Poster-Pop" session chaired by Vivian Walworth. This session's aim was to provide a brief oral introduction to the posters which would be displayed in the afternoon's demonstration session. The session appeared to be well received by the audience and the poster authors were kept busy during the later demo session when their posters were on display. In addition to the scheduled posters, Frank Kooi summarized his poster "Visual comfort of binocular and 3-D displays" which was on show during the demo session, however this paper was officially part of the "Human Vision and Electronic Imaging" conference and consequently will only appear in the proceedings of that conference (Proceedings of SPIE Vol. 4299).

The conference keynote presentation after lunch, "Stereoscopic Computer Animation for Location-Based Entertainment," was presented by Jeff Kleiser from Kleiser-Walczak Construction Company (KWCC) (North Adams, Massachusetts). Jeff's presentation highlighted the wide range of stereoscopic computer animated work that has been performed at KWCC. His talk started with the Robert Wilson/Philip Glass opera "Monsters of Grace", a 73 minute opera played against a giant polarized projected stereoscopic backdrop, projected from 70mm film. Part of the choice to use stereoscopic projection came from the organizers' wish not to travel around the country with a giant model of a foot – a central prop for the performance. KWCC's most well know work to date is "The Amazing Adventures Of Spider-Man" – a combination 3D projection thrill ride which is located at Universal Studios Florida. We were highly privileged to be able to see actual 3D Video footage from the Spider-Man ride projected on the conference's rear-projection screen from dual Betacam SP tapes. Our thanks goes to Universal Studios for allowing us to show this footage. Jeff described some of the background behind this project including the process they used to gauge how much depth-range should be used in the stereoscopic images they were creating. This work remains quite an innovative production due to its use of a new process they called "squinching". For further background about this production you can visit the company's website <http://www.kwcc.com> and read the following articles:

• D.Marren (2000) "Spider-Man 3-D in Orlando" in Stereo World, Vol. 27 No.1, pp.6-12.
• L.Hindus (2000) "Into the Images: ‘Squinching' Immersive 3-D for Ride-Through Experiences" in Advanced Imaging, February 2000, pp. 24-26.

Jeff then discussed another stereoscopic work "Corkscrew Hill" which KWCC is currently completing for Busch Gardens. He also demonstrated some of their non-3D work, which included some special effects for the feature length movie X-Men, and a children's book "Little Miss Spider" adapted into a short cartoon. The keynote presentation was again the most well attended session of the conference, and the speaker earned a very hearty round of applause from the audience in appreciation for a very interesting presentation.

The demonstration session was once again a major highlight of this year's Stereoscopic Displays and Applications conference. Attendees were given a hands-on up-close experience with a large range of stereoscopic hardware and software. The session was chaired by Andrew Woods and Mike Weissman. Demonstrations included:

• The first public showing in the USA of Canon's new dedicated 3D lens for the Canon XL-1 prosumer digital video (DV) camcorder.
• The first public showing of VREX's new DLP based stereoscopic video projector. The field-sequential image was viewed via LC shutter glasses, and the 3D video signal came from a field-sequential 3D DVD.
• Communications Research Center Canada (Ottawa, Canada) demonstrated the MPEG2 transmission of stereoscopic video over a broadband network with a stereoscopic video camera and a 3D 120Hz-CRT-based computer display.
• Several autostereoscopic displays (based on the parallax illumination technique) were on show from Dimension Technologies Inc (Rochester, New York)
• I-O Display Systems (Menlo Park, CA) displayed their various LC shutter glasses systems, 3D camcorder attachment and new 3D CD-ROM titles.
• John Rupkalvis of StereoScope International (Burbank, California) demonstrated a small stereoscopic video camera with the use of a portable polarized 3DTV based on two LCD monitors, a half-silvered mirror and linear polarizers.
• "StereoJet" polarized stereoscopic prints and transparencies from San Francisco Imaging Services (San Francisco, California).
• Shmuel Peleg of University of Jerusalem (Jerusalem, Israel) and Moshe Ben-Ezra from OmniStereoLtd (Jerusalem, Israel) demonstrated their system for capturing stereoscopic panoramas using a single monoscopic "webcam".
• Edge 3D Imaging (Philadelphia, Pennsylvania) demonstrated its microscope accessories for direct-view 3D imaging.
• Digital Optical Technologies (Ithaca, New York) presented their microscope that provided for optical conversion of mono-path high magnification microscopy to dual-path stereoscopic video microscopy.
• Dynamic Digital Depth (Santa Monica, California and Perth, Australia) demonstrated their "Optic Boom" Quicktime plug-in for streaming 3D Video content and their 3D video demultiplexer and scan doubler products.
• The DV120 3D video standards converter and a prototype 3D VGA demultiplexer were demonstrated by Curtin University (Perth, Australia).

Stereoscopic photographs of these displays can be seen at the Stereoscopic Displays and Applications website: http://www.stereoscopic.org

As an encouragement for authors to use stereoscopic display techniques in their presentation, a prize was offered for the best use of stereoscopic display techniques during a conference presentation. At the end of the conference, this prize was awarded to Shmuel Peleg of University of Jerusalem for his stereoscopic panorama presentation "Stereo mosaicing from a single moving video camera". The prize was a VR Visualizer package kindly donated by VREX (Elmsford, New York). VREX also kindly donated a second VR Visualizer system which we decided to award to the presentation we would have most liked to have seen in 3D - this was awarded to Ms. Ji-eun Bahn from the Korean Institute of Science and Technology (KIST) (Seoul, South Korea) for her presentation "Device and software for diagnostics and treatment of binocular and stereoscopic vision impairments".

The new Stereoscopic Displays and Applications CDROM was the first of two major initiatives of the conference committee announced at the conference. The set contains two CDROMs with the full proceedings of the Stereoscopic Displays and Applications conference over the years 1990 to 2000 in a fully searchable Adobe Acrobat (pdf) format. Also in the set are the proceedings of the Engineering Reality of Virtual Reality conference (for the years 1994 to 2000) which has been co-published and co-located with the Stereoscopic Displays and Applications conference since 1994. And as if that weren't enough, the set's second CD contains the papers from a selection of 3D-related SPIE conferences over the years 1977 to 1989. In all, over 600 individual conference papers and over 5000 individual pages of information - this is undoubtedly the largest-ever single collection of stereoscopic imaging related information. The CD is available for purchase via the conference website and costs a mere fraction of what all the individual proceedings would cost if they were bought individually. First-run copies of the CDROM were available at the conference and it proved so popular that supplies sold out.

The Stereoscopic Displays and Applications Virtual Library is the other major initiative. A large number of very good stereoscopic imaging texts have gone out of print, or are otherwise very hard to access or find. It is our intention for this site to hold a selection of texts (books, articles, etc) which have been converted into electronic format. Of course we do have to comply with copyright restrictions, but keep an eye on the conference website - the first such text should be available on the website by mid 2001.

This year's Engineering Reality of Virtual Reality conference highlighted the trend of other disciplines adopting technologies originally developed for virtual environment systems. The session began with papers that point to the migration of immersive technologies into pervasive computing. Koichi Toyota of Nagoya University discussed how multiple camera images could be used to provide human-oriented image restructuring. Yannick Perret of the Universite Claude Bernard Lyon ignored all obstacles and forged ahead to present a clever technique for tracking real objects in a virtual environment using standard imagery. Tuukka Turunen finished the first session with a fascinating look at a service architecture developed at the University of Oulu that will allow upcoming cellular systems to be the backbone of future mobile augmented reality services.

The next session began with Mark Bolas presenting a paper on the future of projection systems based on micro-mirror display elements, specifically multiple participant systems. Julian Brooker's work found that the addition of synthetically generated depth-of-field can improve a subject's performance on a timed visual observation task. Andreas Simon concluded the morning's papers by introducing the audience to his latest work, including an advanced curvilinear projection-based display system.

Steffi Beckhaus woke-up the post-lunch audience by guiding them through her work at GMD to allow users to explore a virtual environment autonomously -yet also provide just-in-time navigational support in a way that would make an electron feel at home. Falko Kuester continued the ongoing annual presentation of great work from UC Davis by introducing VirtualExplorer, a reconfigurable plug-in based framework for two-handed modeling and data exploration.

This year's conference was fortunate to have three papers describing different aspects of the BS-CAVE system developed at the Helsinki University of Technology. Janne Jalkanen took a down-to-earth look at building a CAVE-like system; Matti Grohn described his experiences in using the system for visualizing building services; and Jarmo Hiipakka presented notes on implementation issues of 3D audio in a CAVE-like environment.

The well-known work on retro-reflective displays by the University of Tokyo was refined by Masahiko Inami's description of a ‘talking head' telepresence system, which allows observers to handle objects of arbitrary shapes. David McAllister had the distinct honor of heading the late afternoon session with his sage advice on the problems that are typically encountered using a virtual reality system for a specific application - in this case it was a system for evaluating human performance during emergency power-off aircraft landings. Dr. Hong Hua concluded the day by presenting her work on overcoming some of the typical limitations of head-mounted displays (such as the conflict between accommodation and convergence) by integrating eye-tracking capability into the display and image generation system.

As usual, the program committee did a great job attracting a diverse group of authors and papers with representation from around the world. Thanks to Shojiro Nagata, Andreas Simon, Henry Sowizral, Duncan Stevenson, and Jim Humphries. A special note of appreciation goes to Jim Humphries who is resigning from the committee this year. Jim has helped since the start of this conference and his pecular vision assisted us all in the early days of the field.

Acknowlegements: There are many people we would like to thank for helping make these conferences happen: Brad Nelson from Nelsonex (Los Gatos, California) for stereoscopic projection hardware and support during the stereo conference, the staff from Spectrum AV of Denver, Colorado (special thanks to Scott Major) for general AV hardware and support, and the organizing abilities of the staff at SPIE & IS&T for their help in the lead-up to and during the conferences. But most of all we would like to thank the authors, presenters, and attendees, who ultimately made these conferences the success that they were.

Final Note: Please remember that the conference activities don't stop at the end of the January meeting. There are now many committees that continue their activities throughout the year. The SD&A conference website provides a focal point for these activities and also highlights the activities of past conferences. Visit the conference website to gain an understanding of the past and future of stereoscopic imaging, consider participating on a conference committee, and most of all think now about presenting a paper or attending next year's conference. The Stereoscopic Displays and Applications conference website is located at: <http://www.stereoscopic.org>.