AI comes to the rescue of vague images

SOME PHOTOGRAPHS of famous actress Bridgitte Lin Ching Hsia taken in the 1980s have been "repaired", that is, transformed from blurred into high-density images, and spread online. China Daily's reporter Zhang Zhouxiang explains the artificial intelligence (AI) technology behind the miracle:

We can make a clear photo vague by lowering its density using any image processing software. But until now there was no software which could do the opposite: make a vague image clear.

Most image-processing techniques involve treating the image as a two-dimensional signal and applying signal-processing techniques to it. The higher the density of an image the more information it contains. Which means the software reduces information to make a clear photo vague. And since a vague photo, taken by a camera with fewer pixels, contains less information, the software needs additional information to make it clear. Yet it cannot create the information out of nothing.