Specialists at Dartmouth University in the USA have developed a tool that can spot how much images have been tweaked using Photoshop or other image editing software, something that could aid UK government plans to label retouched images in advertising.
The computational tool was described in a study published on 28 November 2011 in the scientific journal Proceedings of the National Academy of Sciences USA, and scores images on a scale from one to five depending on how much digital retouching they have received, five being the most.
The tool was developed by analysing 468 sets of original and tweaked images, with creators Hany Fari and Eric Kee extrapolating a mathematical way of identifying whether a picture had been retouched, and if so by how much.
When testing the effectiveness of the tool, the researchers comparing its scores to those of 50 people pulled from Amazon's Mechanical Turk outsourcing service. The scores of both the tool and the people polled were very close, validating the abilities of the software.
British government plans to force advertisers to label manipulated photos came after criticism was levelled at unrealistic fashion and beauty images in the media that are accused of leading to body image issues and anorexia among teenagers.
Explaining the need to quantify how much an image has been altered, author Farid explains his belief that British government plans to force advertisers to label images they have retouched won't really achieve much, simply by telling people when a picture has been altered.
"One criticism of the British legislation is that they were presenting a blunt instrument. Photographs would be labelled as retouched or not. Anybody knows that there's different types," said Farid. "It's an interesting scientific problem: How much is too much? That got us thinking about whether we could quantify this."
Wired reports that the American Medical Association has urged advertisers and advocates of more true-to-life images to develop a set of standards - but, as with the objections that forced the British plan into a compromise indicated when an image had been altered, but not how much, finding an acceptable threshold won't be easy.