Adaptive Combined Method for Material Identification in Documents of Historical Interest

Hyperspectral imaging has been widely and consistently applied in the field of Cultural Heritage for material identification. In the specific context of historical document analysis, it is frequently supported and complemented by additional analytical techniques. In this study, we propose a straightforward method for material identification that combines adaptive direct identification—using a reference library of visible and near-infrared spectral reflectance data for pigments—with a KNN classifier applied to an extended spectral range for inks and supports. The method has demonstrated a high degree of accuracy, successfully identifying materials present in both actual historical documents and mock-ups created following medieval techniques. Its performance is illustrated through three spectral image fragments extracted from the HYPERDOC project database.