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Build Your Own 3D Scanner w/ Structured Light

November 23, 2009

I was about to embark on finally fixing my homemade structured light implementation (created in a Computer Vision class), when I stumbled across this amazing site.

Recently at SIGGRAPH 2009 there was a course on 3D scanning with structured light. I wasn’t able to make SIGGRAPH this year because I was working at Walt Disney Imagineering, so I didn’t find out about this course until this week. The course will also be at SIGGRAPH Asia on Dec. 16th, so make your way over to Japan and check it out.

The course features extensive notes explaining structured light and basic Matlab and C++ implementations.

Essentially, structured light uses a projector and a camera to create a 3D scan. Normally humans perceive depth based upon triangulating the location of an object using our left and right eye. In structured light you can think of the camera as your left eye and the projector as your right eye. Through projecting a series of uniquely identifiable codes the camera sees for the projector. The hardest part of implementing this is the calibration of the projector and camera. This involves determining the parameters of the lenses and the location/orientations of the projector/camera.

I’ve spent some time modifying the above code (which was very similar to my own implementation a few months ago, only it works :-P ). The SL code now works with the Canon EDSDK. I am using my Canon T1i DSLR as the camera and an old NEC VT540 projector(1000 lumens).

I also have modified the calibration process to use a red/blue checker board pattern. In my opinion this makes the projector calibration step easier and more robust (I have no facts to back this up). Essentially, you use a red/blue checkboard pattern which appears black/white in intensity under red light. However, the pattern is roughly gray in intensity under white light. This technique come from “A Novel Method for Structured Light System Calibration” by Zhang, S. & Huang, P.

I will be posting my modified source code soon. I would be very interested in turning this into a full fledged open source project. With a minimal amount of work we could probably support most of the common camera SDKs (aka Point Grey, Dalsa etc). It would also be nice to make a GUI and support a wider range of output options. Any takers?

Check back soon for code and goodies.

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Scrim & Dance

November 5, 2009

There are some cool effects in here. Fairly simple with a dancer and a scrim.

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Symbiose

November 1, 2009

Another wonder by the geniuses at  Urban Screen. Judging by the logo on their website, it looks like they use MxWendler. (Correct me if I’m wrong).

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Fla Flav

October 31, 2009

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Anamorphic Packaging

October 15, 2009

Hard coded view dependent texturing!

(snipped from core77)

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Digital Wallpaper by Strukt

October 3, 2009

Interesting 2 projector mapping. Looks like they used Max/MSP.

(correction vvvv)

http://strukt.com/

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Facade Projection

July 30, 2009

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Body Paint

June 18, 2009

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Augmented Prototyping

May 24, 2009

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Light by Levi van Veluw

April 2, 2009

Light

An interesting art piece created by wrapping the artists head in light generating foil. While the piece doesn’t involve projectors, it almost seams to fit into the larger umbrella of spatially augmented reality and it is a truly unique way of abstracting the human head.

From his website:

“The work of Levi van Veluw constitutes series of self-portraits, drawn and photographed by himself: a one-man-process. Past pieces have been termed ‘elemental transfers’; modifying the face as object; combining it with other stylistic elements to create a third visual object of great visual impact. The work created is therefore not a portrait, but an information-rich image of colour, form, texture, and content. The image contains the history of a short creative process, with the artist shifting between the entities of subject and object.

In his latest photographic series, the visibility of this creative process is reduced. Under the working title ‘Light’, Van Veluw has covered his head with strokes of light generating foil. Photographed in total darkness, the highly radiant bright blue light produced by this material, allow it to stand out as an autonomous object. Forgotten are the features of Van Veluw´s face, only its shape remains discernable in the route that each stroke of light takes. Light becomes form and it stands free from any ‘original’ subject. It is this ‘invisibility’ of the production processes that creates the freedom in this image”