Hi,
A forum user has mentioned delay is more in TCP when comparing to UDP. Please refer to discussion in
Gstreamer TCPserversink 2-3 seconds latency - #5 by DaneLLL
So suggest you use UDP. The source supports NV12, so you may try
$ gst-launch-1.0 v4l2src ! video/x-raw,width=640,height=512,format=NV12,framerate=30/1 ! timeoverlay valignment=4 halignment=1 ! nvvidconv ! 'video/x-raw(memory:NVMM),width=1280,height=720' ! tee name=t ! nvv4l2h264enc insert-sps-pps=1 idrinterval=15 ! h264parse ! rtph264pay ! udpsink host=REMOTE_HOST port=5000 sync=0