Can You Clean That Up a Little?
As a frequent Photoshop user and skeptic, there’s a moment in every crime movie that makes me laugh. It’s when the grizzled detective is back at the office, and asks the local pencil-necked, glasses-wearing lab technician, to “bring up the footage of the robbery”. The lab tech types away at his PC, runs the footage, and our hero says “stop it right there.” More typing, and the frame freezes.
And why does he always type? Anybody who’s ever actually used a computer knows that most, if not all, image navigation and manipulation is done with a mouse or other fancy input device.
Then comes the inevitable question: “can you enhance that section?” The nerd at the controls types some more, and zooms in on the indicated section (often with a box and flashy zoom animation). The zoomed image starts as pixelated, but then slowly comes clear to reveal the license plate, tattoo or coffee cup that fingers the killer.
As far as I know, this approach is technically impossible. There’s no way to magically add more pixels to an image that will make it clearer. What you see is, indeed, what you get. Plus, anybody who’s seen security camera footage knows that the feed is typically, at best, mediocre.
To illustrate my point, I did a search and found this nice big screen-cap from a security camera. Ignore the guy in the centre with the goofy hat. Let’s say you wanted to get a closer look at the guy with the tie and glasses. Here’s what he looks like, zoomed to 400%.
As you can see, there’s no new information–we could tell everything about him from the original screen capture. I applied my limited Photoshop acumen to this image, and I could make things slightly clearer, but this image really doesn’t have much more to tell us.
Is that a beard, or a shadow under his chin? What shape is his nose?
It also kills me that police labs in the movies and on TV seem to have customized software for managing and viewing images. The reality is far more mundane. I saw a news piece recently on the Internet team of the RCMP’s child pornography division. They were using Photoshop to examine images and videos to look for clues.
Just as everyone in the movies still owns an answering machine, this is a minor suspension of disbelief that we accept. I was reminded of this phenomenon while watching The Bourne Identity again, where Treadstone’s entirely pursuit of Bourne depends on their ‘cleaning up’ a feed from a security camera to spot Franka Potente’s license plate. Another movie where this kind of photo-manipulation was crucial to the plot was Rising Sun.
Arild Jensen 
