Bispectral coding: Compressive and high-quality acquisition of fluorescence and reflectance

Fluorescence widely coexists with reflectance in the real world, and an accurate representation of these two components in a scene is vitally important. Despite the rich knowledge of fluorescence mechanisms and behaviors, traditional fluorescence imaging approaches are quite limited in efficiency and quality. To address these two shortcomings, we propose a bispectral coding scheme to capture fluorescence and reflectance: multiplexing code is applied to excitation spectrums to raise the signal-to-noise ratio, and compressive sampling code is applied to emission spectrums for high efficiency. For computational reconstruction from the sparse coded measurements, the redundancy in both components promises recovery from sparse measurements, and the difference between their redundancies promises accurate separation. Mathematically, we cast the reconstruction as a joint optimization, whose solution can be derived by the Augmented Lagrange Method. In our experiment, results on both synthetic data and real data captured by our prototype validate the proposed approach, and we also demonstrate its advantages in two computer vision tasks-photorealistic relighting and segmentation.