“Automated method seems to spot forgeries as well as a connoisseur does… The technique, devised by computer scientist Hany Farid and colleagues at Dartmouth College in Hanover, New Hampshire, identifies the artist by analysing an individual’s characteristic brush or pen strokes. It is able to distinguish eight drawings by Bruegel, deemed authentic by art experts, from five acknowledged imitations.
Farid’s program suggests that a painting attributed to the Italian Renaissance artist Pietro Perugino was in fact produced by at least four different artists (presumably Perugino’s apprentices in his workshop). This analysis is also supported by the judgement of art historians.”
More here from Nature.