retouching the planet

What do you think Colorization would be? – Well take a picture, a greyscale one for instance and dye it. When you do this manually it’s a pain-in-the-ass. As far as i know there’s no working automatic solution for this problem. But there is this research project:

“Colorization is a computer-assisted process of adding color to a monochrome image or movie. The process typically involves segmenting images into regions and tracking these regions across image sequences. Neither of these tasks can be performed reliably in practice; consequently, colorization requires considerable user intervention and remains a tedious, time-consuming, and expensive task.

In this paper we present a simple colorization method that requires neither precise image segmentation, nor accurate region tracking. Our method is based on a simple premise: neighboring pixels in space-time that have similar intensities should have similar colors. We formalize this premise using a quadratic cost function and obtain an optimization problem that can be solved efficiently using standard techniques. In our approach an artist only needs to annotate the image with a few color scribbles, and the indicated colors are automatically propagated in both space and time to produce a fully colorized image or sequence. We demonstrate that high quality colorizations of stills and movie clips may be obtained from a relatively modest amount of user input. “

What does that mean? – Well this algorithm automatically creates from this:


Isn’t this awesome? The biggest problem is that it’s just a research project – it’s implemented in Matlab and not available as stand-alone software…too bad. Because it even works with movies.

For more information take a look at their website.

Source 1: Dinge, Zeugs und Sachen
Source 2: Paper: Colorization Using Optimization