Recovery of spectral reflectances of art paintings by a multispectral camera

Abstract

The impression of an art painting largely changes with illuminations. It is required to accurately recover the spectral reflectances of the painting at the spatial resolutions of camera pixel in order to reproduce realistic color images of it under various illuminations. In this study, the experimental results on the spectral reflectances recovered by the use of color image data are described. Usually a color in a painting is not uniform in the two dimensional space, therefore it is very difficult to compare a measured and a recovered spectral reflectance since the measured spectral reflectance by a instrument is the average of the value over an area use for a measurement. This paper describes the experimental results on the comparison between the measured spectral reflectance and the average of the spectral reflectances recovered by plural pixels within the area.