Paper Info
Title
What Is a Good Day for Outdoor Photometric Stereo?
Abstract
Photometric Stereo has been explored extensively in laboratory conditions since its inception. Recently, attempts have been made at applying this technique under natural outdoor lighting. Outdoor photometric stereo presents additional challenges as one does not have control over illumination anymore. In this paper, we explore the stability of surface normals reconstructed outdoors. We present a data-driven analysis based on a large database of outdoor HDR environment maps. Given a sequence of object images and corresponding sky maps captured in a single day, we investigate natural factors that impact the uncertainty in the estimated surface normals. Quantitative evidence reveals strong dependencies between expected accuracy and the normal orientation, cloud coverage, and sun elevation. In particular, we show that partially cloudy days yield greater accuracy than sunny days with clear skies; furthermore, high sun elevation--recommended in previous work--is in fact not necessarily optimal when taking more elaborate illumination models into account.
Year
DOI
Venue
2015
10.1109/ICCPHOT.2015.7168379
2015 IEEE International Conference on Computational Photography (ICCP)
Keywords
Field
DocType
outdoor photometric stereo,natural outdoor lighting,data-driven analysis,large outdoor HDR environment map database,object image sequence,sky maps,normal orientation,cloud coverage,sun elevation,illumination models,shape reconstruction technique
Computer science,Remote sensing,Over-illumination,Artificial intelligence,Elevation,Iterative reconstruction,Computer vision,Surface reconstruction,Optics,Sky,Atmospheric model,Photometric stereo,Cloud computing
Conference
ISSN
Citations 
PageRank 
2164-9774
2
0.37
References 
Authors
19
4
Name
Order
Citations
PageRank
Yannick Hold-Geoffroy1144.30
Jinsong Zhang240.79
Paulo F. U. Gotardo3131.86
Jean-françois Lalonde459037.69