Shadow detection via Rayleigh scattering and Mie theory
Lin Gu, Antonio Robles‐Kelly · 2012
In this paper, we present a method to detect shad-ows in outdoor scenes. Here, we note that the shadow areas correspond to the diffuse skylight which arises from the scattering of the sunlight by particles in the atmosphere. This yields a treatment in which shadows in the image can be viewed as a linear combination of scattered light obeying Rayleigh scattering andMie the-ory. This treatment allows for the computation of a ra-tio which permits casting the problem of recovering the shadowed areas in the image into a clustering setting making use of active contours. We illustrate the util-ity of the method for purposes of detecting shadows in real-world imagery and compare our results against a number of alternatives elsewhere in the literature. 1.