Z.Y. Alpaslan and A.A. Sawchuk, "Three-Dimensional Interaction with Autostereoscopic Displays," Proc. Stereoscopic Displays and Virtual Reality Systems XI Symposium, Proc. SPIE, Vol. 5291, San Jose, CA, 2004. Three-Dimensional Interaction with Autostereoscopic Displays Zahir Y. Alpaslan and Alexander A. Sawchuk 1,2 Integrated Media Systems Center, University of Southern California, Mail Code 2564 Los Angeles, CA 90089-2564. ABSTRACT We describe new techniques for interactive input and manipulation of three-dimensional data using a motion tracking system combined with an autostereoscopic display. Users interact with the system by means of video cameras that track a light source or a user’s hand motions in space. We process this 3D tracking data with OpenGL to create or manipulate objects in virtual space. We then synthesize two to nine images as seen by virtual cameras observing the objects and interlace them to drive the autostereoscopic display. The light source is tracked within a separate interaction space, so that users interact with images appearing both inside and outside the display. With some displays that use nine images inside a viewing zone (such as the SG 202 autostereoscopic display from StereoGraphics), user head tracking is not necessary because there is a built-in left right look-around capability. With such multi-view autostereoscopic displays, more than one user can see the interaction at the same time and more than one person can interact with the display. Keywords: Autostereoscopic displays, interactive displays, video tracking, 3-D display, stereo display. 1. INTRODUCTION Recently, stereoscopic systems have gained popularity due to increases in the processing power of computers and the reduced price of high quality displays. With the emergence of autostereoscopic displays it has been possible to view images, movies and other kinds of data in 3D space without wearing glasses. Several researchers have investigated stereoscopic viewing technology for better 3D data visualization and manipulation, and work on stereoscopic imaging has been increasing. Autostereoscopic (AS) displays make the stereo experience more pleasant by removing the necessity of using glasses. Table 1 summarizes the two main types of current commercially available AS displays along with their image quality and applications. Lenticular based AS displays [1-4] have higher brightness and are better for multi-view (more than two displayed images at the same time) and multi-viewer (more than one person can see the effect) applications. However, because the slanted lenticular screen is used to display multiple views the image resolution of each view is reduced horizontally and vertically, making it difficult to read displayed small text. Barrier screen based systems [4,5] have lower brightness and are more appropriate for single viewer and single view situations. However, their only reduction in resolution is in the horizontal dimension. AS Display Type Resolution Text Image quality Depth Effect Application Cost Lenticular (StereoGraphics, DDD etc.) Reduced to 1/3 both in horizontal and vertical Small text unreadable Image edges are blurred Movement parallax and image parallax Multi view and multi viewer $4,000 - $18,000 Barrier (Sharp) Reduced to half only in horizontal Readable Sharp clean edges Only image parallax Single view, single viewer $3,300 Table 1. Differences between lenticular and barrier technologies in two commercially available AS displays. 1 Author emails: {Alpaslan, Sawchuk}@sipi.usc.edu 2 Phone: (213) 740-4622