Abstract

The spectrum behavior of a typical fluorescent object is regulated by its reflectance, absorption and emission spectra. It was shown that two high- frequency and complementary illuminations in the spectral domain can be used to simultaneously estimate reflectance and emission spectra. In spite of its accu- racy, such specialized illuminations are not easily accessible. This motivates us to explore the feasibility of using ordinary illuminants to achieve this task with com- parable accuracy. We show that three hyperspectral images under wideband and independent illuminants are both necessary and sufficient, and successfully de- velop a convex optimization method for solving. We also disclose the reason why using one or two images is inadequate, although embedding the linear low- dimensional models of reflectance and emission would lead to an apparently overconstrained equation system. In addition, we propose a novel four-parameter model to express absorption and emission spectra, which is more compact and discriminative than the linear model. Based on this model, we present an ab- sorption spectra estimation method in the presence of three illuminations. The correctness and accuracy of our proposed model and methods have been veri fied.