Neuro Productions » Webcam

3D Motion Capturing part 2: Drawing In Space

Kris — Sat, 09 May 2009 12:18:01 +0000

In my previous post I did a first test with 3D motion capturing, it worked, but it wasn’t precise enough to make a 3D drawing app (my initial plan). I did some more experiments with normal web-cams, but they all failed. There was to much “color pollution” to track a small point. So I decided to try it with infrared light.

That did the trick:

I had to build a simple infrared ‘pen’ (picture below) and convert 2 web-cams to infrared web-cams.

How: Open the web-cams. Replace the infrared filters with a filter that blocks all the visible light but won’t block infrared light. Film-negative does that for you.

SourceCode: infra_red_motiontracking_source

3D motion tracking

Kris — Sun, 26 Apr 2009 15:30:11 +0000

2 webcams, Flex and a boring sunday afternoon…

Source code: motion_track_source

Flash/Air Laser Graffiti

Kris — Thu, 07 Feb 2008 16:21:11 +0000

After seeing this amazing video on youtube of laser graffiti (where the software is made in .Net),
I realized that this can also be done in flash. So I made a small laser graffiti Air application.

See here the result:

I would release the source, but it’s not clean and I made it for my screen, projector, camera and webcam settings. But basicly it works like this:

Create a bitmapData object of your video object which displays the camera. With a ColorMatrixFilter you remove all but the red color values. And finally, with the getColorBoundsRect method you get the rectangle object of the red values (= my red laser pointer). the x and y position is the position of the pointer, there you start drawing. Simple as that.

bmd.draw(video)
 
var matrix:Array = new Array();
matrix = matrix.concat([1.5,0 , 0, 0, 0]);
matrix = matrix.concat([0,0, 0, 0, 0]);
matrix = matrix.concat([0, 0, 0, 0, 0]);
matrix = matrix.concat([0, 0, 0, 0, 0]);
 
redFilter = new ColorMatrixFilter(matrix);
bmd.applyFilter(bmd,bmd.rect,new Point(0,0),redFilter)
var maskColor:uint = 0xFF0000;
var color:uint = 0xFF0000;
var redBounds:Rectangle = bmd.getColorBoundsRect(maskColor, color, true);
 
trace (redBounds.x)
trace (redBounds.y)