REDBLIND

When I was researching color tracking with Flash, there were surprisingly few examples. The examples I did find did not have any source to download. So, I am offering up my source code from  my color tracking experiment. The ColorIsolator class is based on an old AS2 algorithm by Mario Klingemann (Quasimondo) for selective color. I’ve translated it here to AS3 and applied it to video from the webcam.

It works like this. Once a color is selected from the video, using a seriess of thresholds, the ColorIsolator drops all pixels that don’t fall within the defined range of the target color. The remaining pixels are set to the target color and getColorBoundsRect is used to pinpoint the remaining blob of color. It’s really simple. I had the general idea, but I didn’t understand how to define a range of  color until I found Klingermann’s code.

I would consider this just a starting point. It actually works very well, but there are a number of things that can be done to improve it. Here are my recommendations to try out:

1. Try using HSV color values rather than RGB.
2. Introduce a palleteMap in place of or in addition to the saturation/contrast ColorMatrixFilter.
3. Add blob detection to ignore anomalies/artifacts of the target color.

Download source here.

All I ask is for constructive criticism and to let me know if and where you use this. A credit to myself and Mario in your source code comments would be nice.

Thanks to Justin Windle (soulwire) for a great exchange of ideas for this.

Here are the results so far for my color/motion tracking project. Turns out that you don’t have to use a difference filter when tracking colors. All you basically have to do is isolate a color range using multiple thresholds. Then run getColorBounds to get the coordinates of the color blob. The one thing I do have to add is blob detection, but with vibrant colors I don’t seem to need it.

Click on the image below to launch the swf. You can use the sliders to adjust the image for your lighting conditions. Click on one of the boxes to assign the colors to the channel. Check out my blog post prior to this one to see where I did most of my research. I’ll release abstracted code after the project is complete.

UPDATE: Source code now available here!