Question / Help Strange Video Glitch When Using Blue Table Mat

[labminion]

When using a blue, self-healing mat in my table top view cam (Logitech c922) I am getting video artifacts (see attached pic). You can see a 35s video of the behavior here: https://youtu.be/6QaSzRcQ0fk

Notes:

• It isn't the CAM. I tested this on both a c920 and c922 in Logitech's GHUB video viewer app and they don't exhibit the issue.
• In OBS, the c920 and c922 both exhibit the behavior (camera independent issue).
• Only occurs with this particular color. Removing the mat or switching to the other side (which is a light blue color) fixes the issue.
• If I introduce other objects on top of the mat it will eventually stop glitching. Exhibited in the video noted above.
• There are no filters attached to the c922 table CAM.

Any thoughts or pro-tips to resolve the issue? Thank you for your time and help.

Jeff
Chief Lab Minion

 

[labminion]

Update: I can stop the glitching if I throttle the FPS from 30fps to 25fps.

I am confused why this makes a difference. If I remove the mat then I can run it at 60fps if I want, but the minute that mat fills the view it has to be throttled to 25fps. Doesn't make any sense. Seems like some sort of underlying issue with OBS?

Jeff

 

[R1CH]

What an interesting find! I think this is the result of the complexity of the mat (lots of sharp lines) combined with the color (different colors require different bandwidth) causing the encoded video stream from your webcam to exceed the available USB bandwidth, or the encoder on the webcam itself is failing with the complexity. Lowering the webcam resolution / FPS, changing the video format or moving to a USB 3 webcam will likely resolve this.