Computer software was used to age an image of the Beatles star

The picture was put together using the latest technology by psychologists and computer scientists at The University of St Andrews.

It marks what would have been the ex-Beatle's 64th birthday on Saturday.

Lennon was killed at the age of 40 when Mark Chapman shot him outside his Manhattan home in New York on 8 December, 1980.

The scientists used the cover image from retrospective 1982 album The John Lennon Collection, in which the star was pictured just before he died, as a starting point.

Elisabeth Cornwell, of the university's perception lab, then used "ageing" software to reproduce the natural effects of growing old on skin texture, hairline and hair colour.

The software - which can be used to assist police inquiries into people who have been missing for many years - is able to manipulate facial images to change the age, sex, race or even perceived personality attributes of an individual.