Separating Fluorescent and Reflective Components by Using a Single Hyperspectral Image

This paper introduces a novel method to separate fluorescent and reflective components in the spectral domain. In contrast to existing methods, which require to capture two or more images under varying illuminations, we aim to achieve this separation task by using a single hyperspectral image. After identifying the critical hurdle in single-image component separation, we mathematically design the optimal illumination spectrum, which is shown to contain substantial high-frequency components in the frequency domain. This observation, in turn, leads us to recognize a key difference between reflectance and fluorescence in response to the frequency modulation effect of illumination, which fundamentally explains the feasibility of our method. On the practical side, we successfully find an off-the-shelf lamp as the light source, which is strong in irradiance intensity and cheap in cost. A fast linear separation algorithm is developed as well. Experiments using both synthetic data and real images have confirmed the validity of the selected illuminant and the accuracy of our separation algorithm.