Artwork imaging from 370 to 1630 nm using a novel multispectral system based on light-emitting diodes

The recent use of multispectral systems as a noncontact method for analysis of artworks has already shown promising results. This study explains the application of a novel portable multispectral system based on light‐emitting diodes (LEDs) for artwork imaging. This method provides spectral information in a spectral range from 370 to 1630 nm with a 25 cm × 25 cm field of view by using two different image sensors in synchrony with 23 bands of irradiation. The spectral information for each point is estimated and validated using the pseudo‐inverse and spline interpolation methods for spectral estimation and three different evaluation metrics. The results of the metrics obtained with both estimation methods show a general good performance of the system over the whole spectral range. The experiments also showed that the selection of the training set for the pseudo‐inverse estimation has a great influence in its performance, and thus, it defines whether or not the pseudo‐inverse outperforms the spline interpolation method. The system is applied in situ to the study of Catalan art masterpieces, and the results demonstrate the potential of a cost‐effective and versatile system using various off‐the‐shelf elements to reconstruct color information and to reveal features not previously identified. © 2014 Wiley Periodicals, Inc. Col Res Appl, 40, 398–407, 2015