Study suggests a third of all fake images go undetected

fake images study university of warwick manipulated street image  credit sophie nightingale
Two objects in this image were altered -- can you tell which ones? Sophie Nightingale/University of Warwick

The abundance of photo-editing apps means anyone with a smartphone can alter an image — but just how easy is it to recognize a fake image? A new study by the United Kingdom’s University of Warwick suggests that a third of all altered images go undetected by the general public. The new data helps pinpoint one of the reasons why identifying fake content online is tough to do — and suggests web browsers should be wary of trusting the images they spot online.

In the study, led by Sophie Nightingale, only 65 percent of participants correctly pointed out the altered images — not much higher than randomly choosing from the images, which would have resulted in getting about 50 percent right. The researchers then showed participants altered images and asked them to identify what was altered — and just 56 percent of those adjustments were correctly identified. Some participants who concluded an image was in fact altered nevertheless couldn’t pinpoint what was changed.

The study involved 659 people between the ages of 13 and 70. According to the researchers, factors such as different demographics, including age and gender, did not influence the results.

The images were of normal scenes, the researchers said, and the manipulations were plausible adjustments including adding objects to the scene that weren’t actually there as well as retouching, such as removing acne and whitening teeth. Some of the images, however, had changes that wouldn’t have been possible in the real scene, like adjusting a shadow so it didn’t exactly match the object that created it.

“When people look at newspapers or magazines, or go on the internet, they’re going to be exposed to fake images, yet our research has shown that people are quite unlikely to distinguish between the real and the fake,” Nightingale says. “So the challenge now is to try and find ways to help people improve at this task. For instance, fake images often contain tell-tale signs that they have been manipulated, and we’re conducting new research to see whether people can make use of these signs to help identify forgeries.”

Think you can spot the fakes? The researcher’s test is available online for anyone to try.