Brightness issues and screen jitter
Posted: Thu Feb 12, 2004 10:00 pm
Hi everyone. Been occasionally reading the forums and have installed ZM 0.9.15 on RH9 a few months ago. I have only played with it a few times. Zoneminder is a brilliant app!!!
Anyway, I'm using an unbranded four input capture card I got off ebay. I can monitor all four inputs at once, using a mixture of colour and b&w cameras, although I can't set ZM to colour, and only 352x288 res - colour works in xawtv, but only b&w in ZM (I'll sort this out some other time though - might be I have to increase the shared memory).
The main problem I want to fix is this: when I monitor only a single input (disable other three inputs), I can get 25 fps at good quality resolution and good contrast. When I enable more than one input, the frame rate decreases (which I expected), but also the brightness on all of the inputs increases. I have to decrease the brightness using the ZM controls, but the resulting images have lower quality. Also, each input screen has a little jitter - it seems to be jumping up and down on successive frames by a few lines - not too bad, but annoying none the less.
Has anyone else had these problems using multi-input cards? Are these problems created when switching the bt878 chip between inputs? Any suggestions for solutions?
David.
Anyway, I'm using an unbranded four input capture card I got off ebay. I can monitor all four inputs at once, using a mixture of colour and b&w cameras, although I can't set ZM to colour, and only 352x288 res - colour works in xawtv, but only b&w in ZM (I'll sort this out some other time though - might be I have to increase the shared memory).
The main problem I want to fix is this: when I monitor only a single input (disable other three inputs), I can get 25 fps at good quality resolution and good contrast. When I enable more than one input, the frame rate decreases (which I expected), but also the brightness on all of the inputs increases. I have to decrease the brightness using the ZM controls, but the resulting images have lower quality. Also, each input screen has a little jitter - it seems to be jumping up and down on successive frames by a few lines - not too bad, but annoying none the less.
Has anyone else had these problems using multi-input cards? Are these problems created when switching the bt878 chip between inputs? Any suggestions for solutions?
David.