A low cost apparatus for capturing stereoscopic video is described and footage from the apparatus is presented in anaglyph form.
A piece of L-shaped extruded aluminum was cut to length and drilled. Cameras are attached with 1/4-20 panhead machine screws, 1/4" nylon washers, and 1/4-20 wingnuts. The apparatus is attached to a quick release shoe for use with a tripod.
Cameras are manually activated for simultaneous filming. A 6.5cm baseline is used (similar to human eye baseline). Longer baselines can be used to increase parallax when filming distant objects.
Left and right video channels are processed and composited in video editing software. Audiovisual cues are used to synchronize the video streams. Depth may be adjusted by changing the x-direction offset between the right and left video channels.
Total cost for cameras and materials: USD 250.
We started with two full color video channels (right and left) — anaglyph (the red/blue method) is not ideal, but it is accessible because you don't need a special screen (just special glasses). We'd like to try this with polarization or autostereo some time.
For the anaglyph version, we overlaid the two tracks in a video editor and set the compositing mode to "screen" (also known as "add" in some editors). We removed the red channel from the right, then we removed the blue and green channels from the left.
We also had to adjust the offset a little bit so the "focus" was on one of the middle birds. Whatever the two channels "line up" on will be the "focus," also known as the "screen plane depth." Whatever is in front of that will "pop out" and whatever is behind will "pop in."
The video editor we used was Adobe Premiere CS4, but you can also do this in cheaper / free software. We tried it in the video sequence editor in Blender (free at blender.org) and got a favorable result.
Components
- 2x Kodak Zx1 Digital Camcorders
- L-Shaped Extruded Aluminum
- 2x 1/4" Nylon Washers
- 3x 1/4-20 Wingnuts
- 2x 1/4-20 Panhead Machine Screws
- Tripod with Quick Release Shoe
The Scientific Analysis and Visualization Initiative at Weber State University
Source: savi.weber.edu