Seminar Archive - 2011
December 14, 2011 6-7 p.m.
Speaker: Scott Daly, Senior Staff Member, Dolby Laboratories
Title: Motion: Displays & Perception
Abstract: This talk will begin by covering the basics of the predominant display technology for television: Liquid Crystal Displays (LCDs), and referred to as LCTV for this application. After setting the foundation for several dimensions of image quality such as spatial, color, temporal, and dynamic range, as well as the corresponding human visual system capabilities along those dimensions, the talk will focus in on the main problem that has hindered the LCTV: motion. Since their introduction, LCDs were known for having a slower and asymmetrical temporal response compared to CRTs, which led to motion blur and flicker, respectively. For many years this hindered the use of LCD technology for television. Improving the temporal response time and the use of digital overdrive techniques led to a substantial reduction in motion blur. Still, some residual blur was visible in panned textures and scrolling text. Further analysis considering human visual system smooth-pursuit eye tracking combined with the hold-type temporal aperture used with LCTV has identified the remaining sources of blur. New techniques such as backlight flashing, black data insertion, and frame rate conversion reduce the motion blur to nearly that of CRT levels. However, the CRT is not necessarily the ultimate benchmark, as it suffers from its own artifacts, especially in the spatial dimension and with slow velocities. This talk will describe the key spatio-temporal properties of the visual system relevant to motion blur, and the various approaches used in LCTV technology toward improving overall moving picture sharpness.
Speaker Background: Scott Daly received a B.S. EE degree in 1980 from North Carolina State University, and then worked for a number of years with early high-resolution laser scanning systems at Photo Electronic Corporation in Florida. Shifting from hardware to wetware, he obtained an M.S. in Bioengineering from the University of Utah in 1984, with a thesis in neurophysiology on temporal information processing of cone photoreceptors. He then worked from until 1996 in the Imaging Science Division at Eastman Kodak in the fields of image compression (receiving a technical Emmy award), image fidelity models, and image watermarking. At Sharp Laboratories of America in Camas, Washington, he led a group on display algorithms. Eventually becoming a research fellow, he had opportunities to apply visual models towards digital video and displays, including starts in human interaction with wall-sized displays, audio perception and stereoscopic displays. These topics led him to recently join Dolby Laboratories in 2010 to focus on overall fundamental perceptual issues, and toward applications whose aim is to preserve artistic intent throughout the entire video path to reach the viewer. He received the Otto Schade award (for applied vision science) from SID in 2011 and is currently a member of IEEE, SPIE, and SID.
Click here to access Scott Daly's slides.