Video encoding dark images (night)

[mito]

Hello,

There is an issue with a network of video cameras. During the day the encoders successfully send multicasts to the server, however, it is alleged that during night time (when image is almost all black), the network traffic is too high.

Is it possible that the encoding algorithm is failing somewhere?

Shouldn't images with one color be easier to compress?

Any opinion is very welcome. Thanx alot!

 

[Karoshi]

If you can tell:
What codec are you using?
Alternatively: vendor/model?

 

[Simon F]

It might be that there is some sort of automatic brightness adjustment going on which would make the images much noisier and hence harder to compress.

 

[mito]

Thanks guy. I don't know the video encoding details, only that the server is called Omnicast.

 

[Karoshi]

One french omnicast company claims its using mpeg2/mpeg4/mjpeg.
Anyway, some equipment I've worked with can be configured as constant quality or constant bandwidth. Maybe a bandwidth cap can be configured per camera on omnicast.
I'm out of my knowledge here, dont know the codec details. What simon says makes sense, btw.

 

[mito]

Interesting. Talking to the guy from the Omnicast company, he was saying that the Omnicast software has a limit of approx. 350 MBps.

The network utilization in the server was around 30-40% on a 1Gb LAN adapter...

We are still studying the case.

 

[mito]

The issue was caused by motion detection during the night, it was generating more traffic.

once disabled, network is fine...