“Nonmatching transport in server reply” when cv2.VideoCapture rtsp onvif camera, how to fix?

Question

I\'m on windows 10 using python 3.6.4, installed opencv (3.4) through pip. Here\'s the code I\'m using:

import numpy as np
import cv2
cap = cv2.VideoCapture(         


        

Answer 1

To force the RTSP to use UDP insted TCP, you can change the enviroment variable OPENCV_FFMPEG_CAPTURE_OPTIONS.

In C/C++ it can be done like that:

#if WIN32
    _putenv_s("OPENCV_FFMPEG_CAPTURE_OPTIONS", "rtsp_transport;udp");
#else
    setenv("OPENCV_FFMPEG_CAPTURE_OPTIONS", "rtsp_transport;udp", 1);
#endif

cap = VideoCapture("rtsp://192.168.0.100:554/onvif1", cv::CAP_FFMPEG);

On Python, I think you can change the environment variable doing that:

import os
os.environ["OPENCV_FFMPEG_CAPTURE_OPTIONS"] = "rtsp_transport;udp"

cap = cv2.VideoCapture("rtsp://192.168.0.100:554/onvif1", cv2.CAP_FFMPEG)

I tested only the C++ solution, the Python one I'm not sure. Please test.