Evaluation of frescoes detachments by partial least square thermography

Several image processing algorithms are available to enhance the results of non destructive evaluation of artworks. This work is focused on the novel Partial Least Squares Thermography (PSLT) technique, that allows a strong data compression. A preliminary test on a fresco sample and a wide survey of the San Gottardo Church (located in Asolo, Italy) have been conducted to locate detachments with an active thermography technique. All the obtained thermal sequences have been post processed with different algorithms, including Principal Component Thermography (PCT), Thermographic Signal Reconstruction (TSR) and PLST. For the latter, two different approaches have been proposed and compared