Let's face it, we all want flawless skin, trimmed legs, toned arms and flatter tummies (in men's case, washboard abs). And celebrities just seem to have it all. Or do they?

Just how tiny is Kim Kardashian's waistline and how really toned are her arms and legs? Does Fergie really have no wrinkles whatsoever on her face? And has Kim Cattrall really aged that gracefully?

People who find themselves asking these questions a regular basis may be pleased to know that researchers at Dartmouth have proposed a software tool for rating photographs for authenticity. The software quantifies the extent of how much these pictures have been digitally altered by programs such as Adobe Photoshop.

The software was proposed by Hany Farid, professor of Computer Science, and Eric Kee¸ doctoral student. Their research is published in this week's National Academy of Sciences journal.

If the tool is used in the future, magazines and advertisements could have a warning label on images similar to a nicotine ad, Farid told Mashable. There could be a number at the bottom of the photo revealing just how much it's been altered.

The proposal of this software comes at a time when the American Medical Association adopted a policy on body image and advertising, encouraging advertisers and others to discourage altering photographs in such a way that it would give an unrealistic expectation of appropriate body image.

Some European countries such as Norway and France have also proposed labelling images that have been altered.

The researchers' tool will have a rating scale of one (very similar) to five (very different).

According to Dartmouth's Web site, the rating system takes into account common practices such as cropping and color adjustment and provides assessment of other kinds of modifications that dramatically change a person's appearance.

Dartmouth's Web site also noted that the researchers consider geometric alterations such as slimming legs and correcting posture, as well as photometric manipulations that might include removing wrinkles and skin blemishes.

We start with the before and after digital images from which we automatically estimate the geometric and photometric changes, effectively reverse engineering the manipulations that a photo retoucher has made, Farid told Dartmouth.

Before
Researchers at Dartmouth have proposed a software tool for rating photographs. It quantifies the extent of how much these pictures have been digitally altered by programs such as Adobe Photoshop. These pictures are after alterations. cs.dartmouth.edu
After
Researchers at Dartmouth have proposed a software tool for rating photographs. It quantifies the extent of how much these pictures have been digitally altered by programs such as Adobe Photoshop. These photographs are before alterations. cs.dartmouth.edu
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