Towards the digital cleaning of Amorsolo's Malacañang Palace By The River

Abstract

A procedure for virtually cleaning a painting is introduced and applied to a digital color image of Fernando Amorsolo’s 1948 oil on canvas "Malacañang Palace By The River." Canvas parts that were covered by the frame for decades appear cleaner and less discolored than the adjacent exposed parts. The RGB (red, green, blue) pixel values of exposed and unexposed parts are transformed and plotted in HSV (hue, saturation, value) color space. The mean color difference between the unexposed and exposed parts was computed and subtracted from the exposed pixel values to transform the pixels back to an estimated unexposed state. The method yields satisfactory results and promises to be useful in the digital cleaning of the whole painting.