From Guardian Unlimited
Software that reveals which paintings are authentic
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A software that helps to authenticate paintings through matching the characteristics of the painting under question to its library of characteristics for that particular artist, such as brushstrokes, colours and type of canvas used etc. The developer of the software said the technique was not designed to replace the opinions of art historians but is meant as a tool to help them reach a decision.

Guess the success of the software as a tool would hinge on building up a representative repertoire of works of individual artists. This task is tremendous when you think of how certain masters have different styles in different phases of their art practice!