Webcam Clip Art: Appearance and Illuminant Transfer from Time-lapse Sequences

Jean-Francois Lalonde, Alexei A. Efros, and Srinivasa G. Narasimhan
ACM Transactions on Graphics (SIGGRAPH Asia 2009), Vol. 28, No. 5, December, 2009


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Abstract
Webcams placed all over the world observe and record the visual appearance of a variety of outdoor scenes over long periods of time. The recorded time-lapse image sequences cover a wide range of illumination and weather conditions -- a vast untapped resource for creating visual realism. In this work, we propose to use a large repository of webcams as a "clip art" library from which users may transfer scene appearance (objects, scene backdrops, outdoor illumination) into their own time-lapse sequences or even single photographs. The goal is to combine the recent ideas from data-driven appearance transfer techniques with a general and theoretically-grounded physically-based illumination model. To accomplish this, the paper presents three main research contributions: 1) a new, high-quality outdoor webcam database that has been calibrated radiometrically and geometrically; 2) a novel approach for matching illuminations across different scenes based on the estimation of the properties of natural illuminants (sun, sky, weather and clouds), the camera geometry, and illumination-dependent scene features; 3) a new algorithm for generating physically plausible high dynamic range environment maps for each frame in a webcam sequence.

Notes
Associated Center(s) / Consortia: Vision and Autonomous Systems Center
Associated Lab(s) / Group(s): Illumination and Imaging Lab and Computer Graphics Lab
Number of pages: 9
Note: For more details, see our project webpage.

Text Reference
Jean-Francois Lalonde, Alexei A. Efros, and Srinivasa G. Narasimhan, "Webcam Clip Art: Appearance and Illuminant Transfer from Time-lapse Sequences," ACM Transactions on Graphics (SIGGRAPH Asia 2009), Vol. 28, No. 5, December, 2009

BibTeX Reference
@article{Lalonde_2009_6482,
   author = "Jean-Francois Lalonde and Alexei A. Efros and Srinivasa G Narasimhan",
   title = "Webcam Clip Art: Appearance and Illuminant Transfer from Time-lapse Sequences",
   journal = "ACM Transactions on Graphics (SIGGRAPH Asia 2009)",
   month = "December",
   year = "2009",
   volume = "28",
   number = "5",
   Notes = "For more details, see our project webpage."
}