CODEWITHSUNDEEP
pythonpython-3.xopencvgstreamer
Ivan Shelonik
Ivan Shelonik

Reputation: 2028

OpenCV with Gstreamer streams with delay, slow and artifacts

There are delays in my gstreamer pipeline using OpenCV. I want to read rtsp stream, get frames, modify them and then output in a new rtsp/tcp/udp streams.

Delay results that produces my pipeline in opencv: enter image description here enter image description here

The code below reads rtsp stream and output to tcp these frames. But OpenCV gives me delay during streaming rtsp camera example as well as using videotestsrc. Can someone help and explain what to do with my pipeline to make it work as fast as possible?

I want to get speed compared to gst-launch. There are no artifacts with delay and slowing using gst-launch compared to OpenCV

gst-launch-1.0 -v rtspsrc location=rtsp://170.93.143.139/rtplive/470011e600ef003a004ee33696235daa ! decodebin ! videoconvert ! x264enc ! mpegtsmux ! tcpserversink  port=8554 host=0.0.0.0

P.S This is the only one working pipeline that I could get with free rtsp camera. btw, I could not stream into rtsp, only to tcp


import cv2
import time

cap = cv2.VideoCapture('rtspsrc location=rtsp://170.93.143.139/rtplive/470011e600ef003a004ee33696235daa ! decodebin ! videoconvert ! appsink', cv2.CAP_GSTREAMER)
f_width = int(cap.get(3))
f_height = int(cap.get(4))
f_fps = int(cap.get(5))
print(f_width, f_height, f_fps)

out = cv2.VideoWriter('appsrc ! videoconvert ! x264enc ! mpegtsmux ! tcpserversink  port=8554 host=0.0.0.0', cv2.CAP_GSTREAMER,0, 20, (f_width,f_height), True)

while cap.isOpened():
  read_start = time.time()
  ret, frame = cap.read()
  read_end = time.time() - read_start
  print('read:', read_end)
  print(ret)
  if ret:
    out_start = time.time()
    out.write(frame)
    out_wtite = time.time() - out_start
    print('write', out_wtite)

  print('-'*10)

cap.release()
out.release()

The speed results on my PC for cap read and write. 

----------
read: 0.06638693809509277
write 0.00010824203491210938
----------
read: 0.06541061401367188
write 0.00011515617370605469
----------
read: 0.06638312339782715
write 0.00010037422180175781
----------
read: 0.06667900085449219
write 0.00010275840759277344
----------
read: 0.066192626953125
write 0.00012063980102539062
----------
read: 0.06572628021240234
write 9.441375732421875e-05
----------
read: 0.0661618709564209
write 0.00011110305786132812

Thanks for any help and suggestions.

Upvotes: 0

Views: 3076

Answers (1)

Ivan Shelonik
Ivan Shelonik

Reputation: 2028

I have found the solution: Just minimize x264enc bitrate and minimize writing fps and all works as a charm. Believe it'll help someone

Upvotes: 3

Related Questions