Patent ID: 8253824

Claim:
A computer-implemented multi-spectral imaging process for computing a reflectance spectral distribution of a captured scene using wide band illumination with known spectral distributions in the presence of ambient illumination having an unknown spectral distribution, the process comprising using a computer to perform the following process actions: selecting a prescribed number of different illumination spectra; capturing multiple images of the captured scene illuminated by said ambient illumination using a camera, wherein each image is captured when the captured scene is further illuminated by a different one of a selected illumination spectra; for each pixel location in the captured multiple images, computing the reflectance spectral distribution of the captured scene associated with the pixel location based on the relative response between pairs of radiometric responses of corresponding pixels in the captured multiple images associated with the pixel location under consideration, given a set of parameters including the selected illumination spectra used to capture each of the multiple images and the response function and spectral sensitivity of the camera used to capture the multiple images.