BBC News Website
The "real face" of television's Doctor Who has been revealed, according to researchers.
With Matt Smith being replaced by Peter Capaldi on Christmas Day, psychologists at the
University of Aberdeen Face Lab have revealed the results of their "face averaging" technology.
Images of all the actors who have filled the role in the long-running BBC show were used to develop the result.
The team said it was a "remarkable" result.
David Robertson, from the Face Lab, said: "It's interesting that the face we have developed is not dominated by the features of any one of the actors to have played The Doctor.
"Rather it represents a combination of the averaged features of each actor to have taken on the role.
"Indeed, this face average could guide future casting directors in their search for the ideal actor to play the Time Lord.
"Of course, Doctor Who takes on an entirely new face each time he regenerates.
"However, in the real world, people keep the same face but it varies considerably across their lifetime, and in photographs. How this relates to our ability to recognise faces is one of the key issues our current research is tackling."
He added: "Evidence has shown that face-averaging could be a powerful tool.
"Previous studies indicate that when you make an average image of a face - essentially creating a prototype with the irrelevant information removed - this significantly enhances the ability of a computer to correctly identify a face.
Image captionA composite image of actors was released for the 50th anniversary
"This work has clear implications for the security sector in terms of the development of facial recognition technology."
Colleague Dr Robin Kramer said: "The software we used allows us to identify specific landmarks on each of the images of The Doctor, such as the eyes, nose and mouth - what we call the 'shape' component.
"We then use these landmarks to average all of the images together, also taking into account their colour and texture."