Cameras with AGC, but need autobrightness help

Question

I have two 0.5lux external cameras with internal AGC being captured with a quad BT878 card, generally works very well, however, at night time, the cameras don't seem to have quite enough gain which leads to very dark pictures under actual conditions.

I can get very good results if I manually set brightness to 200-220, but then come morning the images are almost totally washed out and saturated as brightness needs to be 32. Because the cameras do have internal AGC, using auto_brightness results in continuous oscillation of the images from black through to white.

Short of writing an app to calculate/lookup sunset/sunrise times and then setting the brightness via the HTTP control port, is there anything else I can do?

Environment

Motion version:	3.2.4
ffmpeg version:	0.4.9-pre1
Libraries:	ffmpeg
Server OS:	Debian Stable (Sarge)

-- TheGuv - 19 Feb 2006

Answer

Did you try the Motion auto_brightness feature?

-- KennethLavrsen - 19 Feb 2006

Answer

Hey, thanks for the fast response!

Yes I did try the auto_brightness config option. I wrote above: "using auto_brightness results in continuous oscillation of the images from black through to white."

-- TheGuv - 20 Feb 2006

Closed unanswered. Developers cannot find the right algoritm when we do not have the camera. Seems these cameras are simply not good enough and the Motion auto brightness cannot regulate to the very extreme values without sacrificing the way it works with the cameras that I have tried with.

In fact auto brightness is a feature that never worked very well. Maybe we need to consider a different way than just looking at the average intensity in the Y channel.

-- KennethLavrsen - 23 Jul 2007