Optitrack Duo and external webcam problem

Hi everyone.
I’ve config Plus for sending both Duo and webcam data to Slicer. Duo is working properly but webcam have some trouble.
It is configured as WMvideo device and Duo and webcam are connected to different usb3 ports.
I saw webcam image in just low resolution config (172x144) and with some delay and stops. If I witch off Duo connector, webcam becomes working fine, even in 640*480 mode without delay. It looks like some problem with DirectShow or something similar.
Thanks on advance.

What computer is this? What webcam do you use?

Maybe you could try to connect one or both devices through an externally powered USB hub to make sure the issue is not due to too much power consumption.

You could also try lowering the webcam framerate to see if it helps.

@Sunderlandkyl have we experienced similar issues before?

I don’t remember an issue like this coming up.

@apparrilla What versions of Plus and Motive are you using? Can you upload your config file somewhere?

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You may also try running the webcam and tracker data acquisition in two different PlusServer processes and see if it makes any difference.

Slicer 4.11.0-2020-07-04 r29204
Motive 2.2 Final (last)

Config file:

They are connected to a different USB central port each other and it´s a desktop. I think it´s not a power or bandwidth problem.
Webcam device is 30fps for reference but i´m going to low down for a try.
Two different Plus processes was my first aproach to fit it but it didn´t work.
It´s not really a webcam, it´s a USB endoscope but it works with Win Camera App properly.

Finally NaturalPoint Support Team has answare to me ant it looks like there is no way to fix it:

HI Angel,
Glad to help!
This is a known issue that can’t be addressed, unfortunately. You’ll be unable to run both the web camera and the Duo on the same computer.
OptiTrack Support

Thank you, it is bad news, but useful to know.

This post has been ‘solved’ two years ago with the message it is not possible.
Is there any progress on this topic from then?

I would like to track with an OptiTrack system and capture ultrasound data via an Epiphan framegrabber. Anyone ideas for a workaround?


Please contact OptiTrack support and report back what they said.

As a workaround, you can connect the tracker and camera to two different computers and stream the images and transforms via OpenIGTLink.