Scientists at HP have developed a technique to detect creases in photographs using standard, unmodified flatbed scanners. Once correctly scanned into a computer, software can determine where the photograph's defect is, and artificially correct it to remove any trace of a crease or fold.How does it work?
On the surface, the technique appears relatively simple. Most flatbed scanners use two separate lightbulbs to accurately capture all the color in a photo. By controlling these independently of each other, two slightly different images (each taken from different directions as the bulbs move under the photo) can be captured of the same photograph. From these, rudimentary 3D information can be generated.
With the defect--a crease in our example--identified, software can artificially mask it entirely. Known as "infilling," each pixel inside the scanned crease is replaced by a new one generated from pixels just outside of the crease. The software makes sure the two pixels are similar, to avoid sticking a giant red pixel in the middle of a bunch of green ones.… Read more