Extracting erased text from palimpsests by using visible light

We present a number of strategies to highlight the underwritten text in palimpsests by using spectral diversity imaging. The most common type of spectral diversity is the one featured by standard color images, from which three channels related to different spectral ranges can be extracted. More sophisticated approaches use specialized imaging providing multispectral data from both the visible and the invisible ranges. We show that some results obtained by color decorrelation in standard images can often be compared to the ones provided by specialized imaging.