Eyewitness generated images of suspects in some cases don’t come close to the actual perpetrator but sometimes they come pretty close. The problems lies in being able to match up those police sketches with an actual mug shot in the police database.
This is something that the researchers at Michigan State University sought to fix with a new computer program that will be able to match those sketches with mug shots.
The MSU system doesn’t work on a pixel-by-pixel basis, but instead uses algorithms to match faces based on prominent features such as the structural distribution and shape of the eyes, nose and chin. Given that sketches sometimes end up not looking all that much like the real person overall, but retaining some of their underlying characteristics, it becomes easy to see how a computer program could make connections that people looking at a “WANTED” poster might miss.
The system was put to the test using a collection of sketches from crimes in which the criminal was later identified, and a database of over 10,000 mug shots. It was able to match 45 percent of the sketches to the right photos – at this point, perhaps not good enough to base a conviction on, but certainly an aid in guiding investigators to likely suspects.