Illumination Eigenspace and Shadow Removal
Cast shadows produce troublesome effects for video surveillance
systems. To robustly eliminate these shadows from image sequences
as a preprocessing stage for robust video surveillance, we propose
a framework based on the idea of intrinsic images. Unlike previous
methods to derive intrinsic images, we derive time-varying reflectance
images and corresponding illumination images from a sequence of
images. Using the illumination images, we normalize the input image
sequence in terms of distribution of the incident lighting to eliminate
shadow effects. We also propose an approach which can potentially
run in realtime by introducing illumination eigenspace, which captures
the illumination variation due to weather, time of day, etc., and
a shadow interpolation method based on shadow hulls. (with Y. Matsushita
and K. Ikeuchi)
Primary Reference
(TBA)
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