Gstreamer get 2 4k usb cameras simultaneously and put them side by side

[DaneLLL]

Hi,
For putting the two sources side by side, please try nvcompositor. You can refer to this topic:
Gst for merging 4 webcams sometimes works, and sometimes it doesn't

And need the patch to rebuild nvcompositor:
Gst for merging 4 webcams sometimes works, and sometimes it doesn't - #5 by DaneLLL