If we want to request an image from Nivian devices, here's the route:
http://admin:passAdmin@IPcamara:puertoHttp/mjpeg/snap.cgi?chn=1
By default these cameras come with the DHCP option enabled, so we have to assign them a fixed IP address.
For example, with a camera assigned the address 172.18.217.150 whose credentials are the default ones, this would be the path:
http://admin:123456@172.18.217.150/mjpeg/snap.cgi?chn=1
If we don't want to insert the credentials a priori, it would have the following shape:
http://172.18.217.150/mjpeg/snap.cgi?chn=1
But in this case the browser will ask us for username and password in order to access.