Accurate Video-Rate Multi-Spectral Imaging Using IMEC Snapshot Sensors

Imec's pixel-level integration of spectral filters enables video-rate multi-spectral imaging with very compact cameras which are well-suited for precision agriculture and remote sensing. Current data processing techniques were limited to the reconstruction of spectral reflectance or transmittance and required the subsequent measurement of a spectrally uniform reference target covering the full field-of-view. In this paper, we present a new data processing flow to reconstruct both spectrally and spatially accurate spectral irradiance and reflectance, transmittance or exitance images even when only a small patch of a reference target is visible in only one of the acquired frames or when only a spectrometer measurement of the illumination spectrum is available. The accuracy is illustrated on lab and outdoor measurements. The presented data processing flow facilitates the use of the imec snapshot cameras for nearly any application, from disease detection in an orchard over coastal water quality inspection to accurate object tracking in spectral videos.