Help needed with ARTK+Tracker help patch

I am new to vvvv and I need some basic information on using the ARTK+Tracker help patch.

First, I was wondering why does it work differently on two computers?
When I run it on my laptop with a built-in webcam, I can see the video stream and the teapot (with a fixed position - I assume it is fixed, because I’m not using any markers).
On another computer at my university the renderer showed only black background. The VideoIn node is fine, and the video stream finally showed up in the renderer when I deleted the group node and replaced it with a new one, but the teapot still wasn’t there.

Secondly, where can I find some AR markers for printing? I’ve stumbled upon some pdf files in one of the ARToolkit zip files, but now I can’t find it. Maybe there is a source you would recommend?

And finally, how can I “teach” or “train” the program to recognise the markers?
I’ve noticed the Marker Files pin - at my university it shows the path to freeframes folder, but on my laptop there are just some characters, like “rÜ” :|
Should I put the markers in the freeframes folder? If so, in what file format?
Or does this “training” work in some other way?

I would very, very much appreciate your help with any of my questions :)


are you sure you tried with the same beta30 + correct addonpack on the two computers? if yes, then i suspect different camera drivers on your two pcs causing different troubles.

with this node there is no way to “train” your own markers. the functionality for the Marker Files was never implemented.

note that the library this node is using is no longer developed. their old page is here: this is also where you may find a download that includes printable markers.

I think it’s the same vvvv version on both computers.

If there are some markers that are already recognised by ARTK+Tracker, that’s great. I don’t need to "rain my own markers, I just need to use three markers in my program. Please don’t tell me there aren’t any that work :(
I’ve seen these two examples of vvvv and ARTK+:
Where did those guys get their markers from?
Are the markers from this link you gave me going to work with this patch?

yep, they’ll work.

Thanks for all the help, the patch now works fine :)

I have another question: I would like to replace the teapot (or other mesh) with a Quad that would be displayed directly on a marker. But I don’t know how to transform it, as I can’t figure out how to use the 4x4 matrix I get from the ARTK+Tracker (I called it “output matrix” in the patch). How can I get the marker’s coordinates/translation/rotation and apply them to the quad?
For now, I replaced the teapot with a box, and set its height to a very small value, but the quad would be much better.

Here’s the patch, plus some markers and the texture I’m using.

marker tracking.v4p (24.9 kB)

quick guess without looking into your patch:
just replace the box with a grid node to get a quad-like appearance. ;)

Works great! Thank you very much :)
I just needed to scale it and rotate it, because it was displayed at 90-degree angle ;)

By the way, is there any way to detect the marker positions once, and store them somewhere to use later?
Let’s say I have a box in front of a camera, put three markers on it, they are detected, but then I’d like to take them away, and project some images on the box exactly where the markers were.

hey mayast, check S+H (Animation) and/or start a new topic for this new question.