ilteris kaplan blog

Reading Golan Levin's Paper

January 22, 2006

I was reading Golan Levin’s paper about Computer Vision, and this area seems has lots of potential overall. In the beginning of his paper he gives a historical background of Computer Vision through Myron Krueger’s works, a figure that coined the term “artifical reality”. It looks like it is the first HCI using camera and computer vision. Another peak point for me about this project, it allows two participants in mutually remote locations to participate in the same projection. That is a great route I should be aware of.

Next piece is Levin’s collaborative work with Lieberman called Messa di Voce. Basically it is a tracking system of your head which spits out circles according to level of your sound that is transforming through a mic. Since it addresses good points about HCI and possible outcomes of computer vision in this sense, it is a good project.

There are numerous other projects as well but the one I like, since it is using physical computing, is an installation called Standarts and Double Standarts(2004) by Rafael Lozano-Hemmer. This work consists offifty leather belts suspended at waist height from robotic servo-motors mounted on the ceiling of the exhibiton room. Controlled bu a computer vision-based tracking system, the belts rotate automatically to follow the public, turning their buckles slowly to face passers-by. In its conceptual sense, it “turns a condition of pure surveillance into an ‘absent crowd’ using a fetish of paternal authority: thebelt”.

In the second part of the paper **Levin **explains elemantry computer vision technics which are frame differencing, which attempts to locate features by detecting their movements, background substraction, which locates visitor pixels according to their difference from a known background scene, and brightness thresholding, which uses hoped-for differences in luminosity between foreground people and their background environment.

He has a detailed explanation in here with code samples: Link.

Written by Ilteris Kaplan who still lives and works in New York. Twitter