Photo credit: Windell H. Oskay,
on creative engineering and new media art


January 2nd, 2006


Catch virtual snow with your shadow

Interactive art piece by artist Sachiko Hayashi produced at the Interactive Institute in the context of the Man Machine exhibition (2005). Developed by Sachiko Hayashi, Fredrik Bridell and Olof Bendt.

In this piece, images of falling snow flakes are projected onto a projection screen. The visitor is invited to step in front of the screen, so that the visitor blocks the projection and casts a shadow on the screen. When a visitor’s shadow falls on a snow flake (as when you are holding up your hand and the snow “falls” on your hand), the snow flake vanishes.

There are different types of snow flakes. Some of the contain sounds (made by invited sound artists), and some of them contain interview clips featuring people telling you about their experiences of snow.

To let you in on the secret of the magic, there’s a video camera that watches the back of the projection screen. The projector and camera are aligned so that a certain pixel on the projected image appears on a certain (predictable) pixel on the camera image. This way it is a relatively simple task to grab a frame from the camera and look at the pixels around the areas where the snow flakes are. If they come back as almost black, somebody’s blocking the image. The snow flake is removed, and the sound is released. Other than figuring this out I also actually made it, using Macromedia Director and the Myron WebCamXtra.

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