Temporal Dithering of Illumination for Fast Active Vision

  • Authors:

  • Srinivasa G. Narasimhan;Sanjeev J. Koppal;Shuntaro Yamazaki

  • Affiliations:

  • The Robotics Institute, Carnegie Mellon University, USA;The Robotics Institute, Carnegie Mellon University, USA;National Institute of Advanced Industrial Science and Technology, Japan

  • Venue:
  • ECCV '08 Proceedings of the 10th European Conference on Computer Vision: Part IV
  • Year:
  • 2008

Quantified Score

Hi-index 0.00

Visualization

Abstract

Active vision techniques use programmable light sources, such as projectors, whose intensities can be controlled over space and time. We present a broad framework for fast active vision using Digital Light Processing (DLP) projectors. The digital micromirror array (DMD) in a DLP projector is capable of switching mirrors "on" and "off" at high speeds (106/s). An off-the-shelf DLP projector, however, effectively operates at much lower rates (30-60Hz) by emitting smaller intensities that are integrated over time by a sensor (eye or camera) to produce the desired brightness value. Our key idea is to exploit this "temporal dithering" of illumination, as observed by a high-speed camera. The dithering encodes each brightness value uniquely and may be used in conjunction with virtually any active vision technique. We apply our approach to five well-known problems: (a) structured light-based range finding, (b) photometric stereo, (c) illumination de-multiplexing, (d) high frequency preserving motion-blur and (e) separation of direct and global scene components, achieving significant speedups in performance. In all our methods, the projector receives a single image as input whereas the camera acquires a sequence of frames.