Large File Sizes with files recorded at night (low light)

[rheide 0]

All -

I'm new here and trying to help a friend with his system. I came in blind so I've had to learn everything as I go. We are working with a GV-800B Card with 2 attached cameras and Geovision Multicam Software - version 8.5.9.0

 

Things are working well after upgrading the software (we had an issues where the browser kept saying it wanted us to enable 3GPP on the webserver but I couldn't find that in 8.5.5.0 - anyway, we upgraded and that message went away.

 

I installed a little app on the server called MediaInfo so I could see information about the video files because I was noticing some 5 minute videos were 30MB and others were 500MB. So - getting to my question, Is there a setting in the software (or anywhere) to set the codec and bit rate for the recording? As we all know, we can record FULL HD in smaller files compared to what I'm seeing. When I'm in the Control Center (network settings), I see it lets me change between Geo H264 and Geo Mpeg4 but I'm not sure if that is for recording or streaming etc.

 

One other important thing to note, the files recorded during the day time are the ones that are about 50-55MB, as soon as it starts to get dark, they slowly bump up to 140MB, to 290MB and then cap out around 750MB by night time.

 

When viewing the video stream within each saved file, it looks like the codec is using a variable bit rate.

File 1 at noon = 57MB, GeoVision Advanced MPEG-4, Overall bit rate 1,598Kbps, 704*240, 30fps

File 2 at 3:00pm = 60MB, GeoVision Advanced MPEG-4, Overall bit rate 1,696 Kbps, 704*240, 30fps

File 3 at 8:30pm = 765MB, GeoVision Advanced MPEG-4, Overall bit rate 21.4Mbps (WOW), 704*240, 30fps

 

While I would still argue that the 57MB file could be GREATLY compressed, at this point, I'm just looking for a solution to make the "night time" files smaller. Even if we could just change that to a constant bit rate, it would solve some of the problem.

 

Sorry for the long post and thanks in advance for any help!

Randy

[gb5102 0]

Its normal for nighttime recordings to be larger with many cams since there is more 'noise' in the image at night, but your file sizes are definitely excessive. If you have really cheap/noisy cams, that's probably the root cause, but there's a few things to check on the DVR.

 

-make sure you are using h264 codec, its much more efficient than older gv-mpeg4 codec(in the 'camera configure' menu)

 

-set the 'noise tolerance' setting to high to limit false motion detection(in the 'camera configure' menu)

 

-you can also enable the low-pass filter(in the 'video analysis' menu)

 

-if your cameras are super noisy at night you might just have to live with it or replace them with something better. If cams have a setup menu or dip-switches you might be able to tweak some settings there to improve the nighttime image

 

Let me know if this helps!

[rheide 0]

gb5102 - thanks for all your input.

 

Can you tell me if this is the "Camera Configure" screen you are talking about?

 

I don't see any codec options.

 

Also, if anyone else can comment - is there some place to tweak the bit-rate? If I can just set it to a CBR, this should take care of everything.

 

Thanks again!

R

[gb5102 0]

Yes, that's the right screen, click the green arrow next to "Round-the-clock"

 

No way to set CBR...

[gb5102 0]

Also, just a heads up, there is a setting for h264 codec called 'noise detection to reduce file size' which basically 'blurs' areas of the image where it sees a lot of noise. It does save space, but i find the effect to be really annoying, also it causes loss of video information so you could easily miss something important, IMO.

[rheide 0]

gb5102 - Thanks a bunch for your help! Much appreciated!