It's really exciting news that computer software has confirmed a portrait of Anne Boleyn – really disturbing that the iconic portrait held by the National Portrait Gallery UK may not be authentic. What's going on?

Computer scientist Amit Roy-Chowdhury, who works at the University of California, Riverside, has applied his facial recognition software to the only image that we have of Anne Boleyn which was produced while she was still alive. It's a commemorative lead coin created to celebrate the birth of her first child and so it is likely to be an image approved by people who knew her, perhaps even by Anne herself.

The medal, now held by the British Museum, shows some signs of age and wear. The breasts seem to be rather outstanding for a woman in a stomacher, the nose is very big indeed and the eyes are rather crooked. This is not a convincing portrait of a woman so beautiful and entrancing that she turned the king of England head over heels with love and the kingdom upside down.

However, the computer compared this rather battered image with that of the existing portraits of Anne to find the closest match and came up with the ‘Nidd Portrait’ but rejected the National Portrait Gallery version. The trouble with the provenance of Anne Boleyn portraits is that none seem to have survived the destruction of her images undertaken after her disgrace. Just as her initials were carved over in the stonework, her portraits were painted over or destroyed. All the images we have of the queen were painted years later, sometimes to please her daughter Elizabeth I by artists too young to ever see her.

Professor Roy-Chowdhury warns that his work is not a final solution to the question of the appearance of the queen. His program has to allow for different art styles, and damage to the portraits. But it is an exciting day when a portrait is authenticated – though the curators at the National Portrait Gallery will probably not be feeling so happy. Not even 'the moost happi'.

Images: Nidd Portrait from Private Collection/Bradford Art Galleries and Museums, via Wikimedia Commons. Medal © The Trustees of the British Museum. Portrait labelled 'Anna Bolina' © National Portrait Gallery, London.