How to interact and get live stream from camera - opencv

Question

I have a Garmin VIRB XE camera, and want to get a live stream and interact with camera like getting GPS data. I could get the live stream by VLC media player and also could post commands to the camera by CURL from windows command prompt, but i can't get the live stream using OpenCV and interact with camera using requests library in python.
I can get a live stream from "rtsp://192.168.1.35/livePreviewStream" using VLC media player's network streaming feature, also could interact with camera, for example by "curl --data "{\"command\":\"startRecording\"}" http://192.168.1.35/virb" from command prompt I could start the recording, but the following codes are not working.
'''
import simplejson
import requests
url='http://192.168.1.37:80/virb'
data = {'command':'startRecording'}
r=requests.post(url, simplejson.dumps(data))
'''
or
'''
import cv2
capture = cv2.VideoCapture("rtsp://192.168.1.35/livePreviewStream")
'''
The post return the error
"ProxyError: HTTPConnectionPool(host='127.0.0.1', port=8000): Max retries exceeded with url: http://192.168.1.37:80/virb (Caused by ProxyError('Cannot connect to proxy.', RemoteDisconnected('Remote end closed connection without response')))".
Also the capture could not get any frames.

Answer 1

Since you have already confirmed that your RTSP link works with VLC player, here's a IP camera video streaming widget using OpenCV and cv2.VideoCapture.read(). This implementation uses threading for obtaining frames in a different thread since read() is a blocking operation. By putting this operation into a separate that that just focuses on obtaining frames, it improves performance by I/O latency reduction. I used my own IP camera RTSP stream link. Change stream_link to your own IP camera link.
Depending on your IP camera, your RTSP stream link will vary, here's an example of mine:
rtsp://username:password#192.168.1.49:554/cam/realmonitor?channel=1&subtype=0
rtsp://username:password#192.168.1.45/axis-media/media.amp
Code
from threading import Thread
import cv2
class VideoStreamWidget(object):
def __init__(self, src=0):
# Create a VideoCapture object
self.capture = cv2.VideoCapture(src)
# Start the thread to read frames from the video stream
self.thread = Thread(target=self.update, args=())
self.thread.daemon = True
self.thread.start()
def update(self):
# Read the next frame from the stream in a different thread
while True:
if self.capture.isOpened():
(self.status, self.frame) = self.capture.read()
def show_frame(self):
# Display frames in main program
if self.status:
self.frame = self.maintain_aspect_ratio_resize(self.frame, width=600)
cv2.imshow('IP Camera Video Streaming', self.frame)
# Press Q on keyboard to stop recording
key = cv2.waitKey(1)
if key == ord('q'):
self.capture.release()
cv2.destroyAllWindows()
exit(1)
# Resizes a image and maintains aspect ratio
def maintain_aspect_ratio_resize(self, image, width=None, height=None, inter=cv2.INTER_AREA):
# Grab the image size and initialize dimensions
dim = None
(h, w) = image.shape[:2]
# Return original image if no need to resize
if width is None and height is None:
return image
# We are resizing height if width is none
if width is None:
# Calculate the ratio of the height and construct the dimensions
r = height / float(h)
dim = (int(w * r), height)
# We are resizing width if height is none
else:
# Calculate the ratio of the 0idth and construct the dimensions
r = width / float(w)
dim = (width, int(h * r))
# Return the resized image
return cv2.resize(image, dim, interpolation=inter)
if __name__ == '__main__':
stream_link = 'your stream link!'
video_stream_widget = VideoStreamWidget(stream_link)
while True:
try:
video_stream_widget.show_frame()
except AttributeError:
pass