Got Wansview NCM625GA to work. Should I use jpeg or rtsp?

[marcmerlin]

I have a NCM625GA a 1080p motorized webcam at an unbeatable price ($125 on amazon), but the web interface isn't exactly linux friendly.

However you can play its HD stream without problem with vlc rtsp://ip/live/ch0 and thanks to their support, I also got the magic URL to get jpegs from it: http://ipaddr/mjpeg/snap.cgi?chn=0

I've added it along with instructions for zoneminder on:
http://marc.merlins.org/perso/linuxha/p ... l#NCM625GA

Just curious though: am I better off using RTSP where apparently I have to throttle to 3 fps on the camera, or zoneminder ends up with half frames from time to time (is that normal?)
Or should I switch to jpeg polling as fast as zoneminder can suck jpegs from the camera via http (and not worry about decoding rtsp, half frames, and all that stuff?)

Thanks

[knight-of-ni]

It depends.

ZoneMinder has three different source types to choose from when using an RTSP url from a typical ONVIF type camera:
- ffmpeg
- libvlc
- Remote/RTSP

None of them are perfect. Try them all and see which one works the best in your particular environment.

All of the above methods involve transcoding h.264 video from the camera into jpeg's, which is cpu intensive. You typically will not be able to run many 1080p cameras using the average desktop computer w/o making compromises.

If you've got a weak cpu and/or many cameras, then you may want to consider jpeg polling or mjpeg streaming depending on what the camera supports. This method will use significantly less cpu, but it will use significantly more network bandwidth. The increase in bandwidth consumed will be an order of magnitude greater.

[marcmerlin]

It depends.

All of the above methods involve transcoding h.264 video from the camera into jpeg's, which is cpu intensive. You typically will not be able to run many 1080p cameras using the average desktop computer w/o making compromises.

Thanks for explaining. I've checked that a single jpeg at 1080p is about 170KB, so 3fps is 0.5MB/s
This is actually quite ok network-wise for me, either on gigabit ethernet, or one of my 3 wireless networks.

So I'll probably go the jpeg route, thanks.

[imntreal]

So, I've been trying to get a NCM625GA working. I'm able to pull images manually, using http://username:password@ip/mjpeg/snap.cgi, but Zoneminder is only giving me blank blue images. Any idea on what to look at? I've got one other camera that's working fine. Thanks.

[marcmerlin]

There is a bug in their http server and it does not return proper headers. This makes zoneminder unhappy.
As a result, I had to use the RTSP stream for zoneminder.

[marcmerlin]

BTW, I posted the settings to use on my page: http://marc.merlins.org/perso/linuxha/p ... l#NCM625GA

[imntreal]

RTSP did the trick. Thanks.