Stream data with gstreamer and recieve with opencv python

[abolfazl_asari]

hi everybody
i just want to send live feed of csi camera (imx 477 12mp) from jetson nano to an other linux system .
for preventing fps dropping because of converting image format that could readed by jetson nano and othe things that make process slower i decide to use rtp or rtsp to send data from jetson nano to other system .
i can send camera feed from jetson and recieve in other system only in terminal .
in jetson i use nvarguscamera as source and in other system i’m using udpsrc as src in command and it will work fine .

but when i wanna read data in linux system (not jetson nano) i dont know who to use gstreamer elements and which source and sink should be used.
for practice i use udpsrc as source and appsink ass sink element and this dosent work (sample code below)

gst_line2= ‘udpsrc host=10.42.0.1 port=5000 caps = “application/x-rtp, media=(string)video, clock-rate=(int)90000,encoding-name=(string)H264,payload=(int)96” ! rtph264depay ! decodebin ! videoconvert ! appsink’
video_capture = cv2.VideoCapture(gst_line2, cv2.CAP_GSTREAMER)

can you tell me which elements i should use and how i gonna use them??

[kayccc]

Your topic was posted in the Orin Nano category. I am moving this to the Jetson Nano category for visibility.

[DaneLLL]

Hi,
It sounds like OpenCV in the linux system (not jetson nano) does not enable gstreamer. You may try to run this:
Gstreamer TCPserversink 2-3 seconds latency - #5 by DaneLLL

If this works on the linux system:

$ gst-launch-1.0 udpsrc port=5000 ! 'application/x-rtp,encoding-name=H264,payload=96' ! rtph264depay ! avdec_h264 ! xvimagesink sync=0

You can then try

gst_line2= 'udpsrc port=5000 ! application/x-rtp,encoding-name=H264,payload=96 ! rtph264depay ! avdec_h264 ! videoconvert ! video/x-raw,format=BGR ! appsink '

[abolfazl_asari]

hi daneLLL
the first command will work in terminal very well
but second line (gst_line2= …) not work in python
and about gstreamer in python i think it should be enabaled because it work when i wanna take image straight from camera in python .

do you have another solution to solve this problem ??

[Honey_Patouceul]

Having gstreamer working in python may not be enough…the question is does your opencv version running from python support gstreamer.
What gives from your pyhton:

import cv2
print(cv2.getBuildInformation())

Check for GStreamer SUPPORT : should be YES.

If ok, you may tell more about how you’re using it.

You may try:

cap = cv2.VideoCapture('udpsrc port=5000 ! application/x-rtp,encoding-name=H264,payload=96 ! rtpjitterbuffer latency=500 ! rtph264depay ! avdec_h264 ! videoconvert ! video/x-raw,format=BGR ! appsink drop=1', cv2.CAP_GSTREAMER)