Network camera framerates

[RandomJoe]

I bought a D-Link DCS-900 network camera (wired), and set up the ZoneMinder software last night. It's working quite well, considering my server is low on memory (Dell PowerEdge 600SC 2.4GHz 256MB). The only problem I'm having right now is the abysmal framerate, which is reporting right around 0.90!

The camera is set up for 320x240, color, and I've tried all the compression settings it has to offer as well. Regardless of settings, I get the same rate. The camera is definitely capable of sending faster, if I go to its web interface and click the 'java' link it gives me very nearly live, full-motion video. Going to 640x480 only slows it down slightly. Not sure if the camera does something tricky to accomplish that or not...

I did a bit of searching, but didn't see anything on expected framerates for network cameras, anyone know? What I'm getting now is fine for basic security purposes, but it sure is jumpy... I get maybe two frames of someone walking past.

Further details, this is a Slackware 9.1 system, so I had fun loading all kinds of Perl modules off CPAN, among other things. Not sure if that might have something to do with it - missing items maybe? I kept adding things until the logs stopped complaining. Now I only get occasional 'zmc crashed' type messages due to memory, I'm sure - the system has only about 6MB free at the moment!

More memory on the way... (Along with two more cameras!) At which point I'll also be reloading the system, upgrading to Slack 10 and paying a lot closer attention to what I am doing!

Any suggestions or thoughts are greatly appreciated.

Thanks,
Joe

[zoneminder]

What path are you using to capture your images? I have a DCS-1000W and the jpeg image path (IMAGE.JPG) gives about 1fps (wireless or wired) whereas the mpjpeg path (video.cgi) is much better. Does your camera support multi-part jpeg streams? If so you should get much better performance.

Phil,

[RandomJoe]

Wow, that was it! I was using the IMAGE.JPG. Switching to video.cgi immediately upped the rate to 16-18 fps.

Great software, can't wait to finish out the system!

Thanks again!
Joe

[infinity005]

after switching my DCS-900 to video.cgi, my CPU is now at 80-90 %.

I only have one camera setup so far also!

[RandomJoe]

I saw a similar thing. What I found, though, is that the load would go all over the place. If I actually logged into the machine, it would occasionally spike high, but otherwise stayed quite low. The value showed on my Zoneminder page would tend to stay higher, for some reason. (Perhaps when the page updated, it caused a spike in CPU, so that's what it saw...?)

When I would actually view the cameras real-time, it would go up and stay up.

Interestingly, the usage really didn't go up much more after I added two more cameras.

My Zoneminder machine is a P4-2.4GHz, and I was viewing on a second machine, so perhaps that contributed to the lower values I saw. Most of the time I peaked out at 60-70%.

[infinity005]

interesting. the server running zoneminder for me is a 1ghz 512mb ram system. what do you have your frame rate set to on your dcs-900's? I noticed much better performance when I set it to 1 fps. I'm going to try auto detect in a few days after benchmarking what i currently have.

[RandomJoe]

I played around with all kinds of settings, but wound up just putting the cameras on Auto framerate, Very Low compression, 640x480. After a while the three settled out to around 8 fps each. I thought it was interesting, at first one camera got up to 10-12 fps, and one was clear down around 4, but eventually they all equalled out.

I found that I didn't like anything much below 5 fps, it just got way too jumpy. Coupled with the annoyingly narrow field of view of these cameras, I could easily miss someone walking across the camera's field of view. The 8fps has worked out fine though.

I was originally thinking the limitation to framerates was on the server side, but it wound up being simply the ability of the camera to send images. It has a 10/100 Mbps ethernet port but there's no way the camera's processor could send that fast. After testing every compression level, and multiplying the size of the JPGs by the framerate, I always wound up with basically the same Mbps transmitted by the camera (seems like it was around 2-2.5 Mbps - it's been a while).