Smearing

[liderbug]

Nice new cam 1920x1080 RSTP. Took a while but I got it working - except after a few minutes the top 15% is good and the bottom smears then clears up - "ALARM". The only other posts I've found suggests lowering FPS fixed their problem - not mine. Suggestions?

vlc "rtsp://sg11:554/user=admin&password=&channel=1&stream=0.sdp" (?tcp)
runs fine ... forever (well at least until I give up waiting for smearing). And the tcp bit doesn't change anything.

Thanks
Cchuck

[BiloxiGeek]

Do you have the frame rate defined in the zoneminder definition? In the General tab look at "Maximum FPS" and "Alarm Maximum FPS". I accidentally set those to match one of my IP cam's and it caused smearing. Set the frame on the camera and leave them blank in the monitor definition on the ZM side.

[liderbug]

Both blank and I changed the FPS at the camera to 10 - no joy...

[TheKorn]

Are you using ffmpeg as the source type by any chance?

[liderbug]

yes
ffmpeg
mondet
noblend
noblend
----------
rtsp://sg11:554/user=admin&password=&channel=1&stream=0.sdp?tcp
24 bit color
1920
1080
norm
disabled
---------------------
just for fun I switched to libvlc - time will tell
---------------
Next morning - much better. Though there have been a couple of smears and one gray?
But I can live with 1:10 bad:good.

Thanks

[TheKorn]

This is actually a known bug with ffmpeg, and at least a medium part of why vlc was introduced into 1.27. Suggest trying libvlc as your source type instead of ffmpeg.

[liderbug]

I did/have and I going to say [SOLVED]

Although, and only a very minor problem, when I play back an alarm it sometimes, it, ah, does a Superman move.
The car passes by then does a horz. smear - no not smear - sooooorrrrt oooofffff - you know when Superman
streaks away and some of his image is still where he was but he ain't.....

[kkrofft]

In my case I tried everything you did with similar results ( still had smears and gray screens a few times a day). I used the camera's native app to play with the encoding settings, specifically the iframe rate. I lowered it from 100 to 25 and the problem went away completely. From what I read, one of the causes of smears is a dropped iframe. This means that the following frames have no reference and are all corrupted. So I think what I have done is to
set it so there are fewer iframes so it has less to drop. Seems a little counter intuitive since with fewer master frames dropping one should be more catastophic. But it worked for me.

[hesral]

What you call superman smear may be what they call motion blur. It is caused by a long shutter speed. The camera image chip is exposed for too long. Look for shutter speed in the camera image settings or exposure time or something. If you are in a country with 60hz power frequency, the shutter speed should be divisible by 60, so 1/120 might be a good setting. Else you probably have 50hz, and should set it to 1/100. You may find that the image gets darker as you do this, especially at night. In that case turn on auto iris, that most new ip cameras come with. Picture quality may get worse as auto gain noise rears its ugly head, depth of field blows your focus etc, but there usually isn't much detail in a motion blur either.

here is a little guide from axis on the problem:
http://www.axis.com/academy/low_light_s ... _light.htm

[liderbug]

I knew that (sure he did) or at least I should have... Thanks

[liderbug]

Not 100% but 99%

ffmpeg -i "rtsp://sg11:554/user=admin&password=&channel=1&stream=0.sdp" -vcodec libx264 -preset ultrafast -tune zerolatency -r 10 -async 1 -acodec libmp3lame -ab 24k -ar 22050 -bsf:v h264_mp4toannexb -maxrate 750k -bufsize 3000k -f mpegts out.avi

[linuxsense]

Is this a wifi cam or is it wired? I have found the issue you describe to be a much bigger issue when using a camera with inconsistent latency over the network like you often have with wifi cams.

[yibi]

In my case, I had to remove the Maximum FPS and Alarm Maximum FPS values. Setting the values to anything else (even in sync with the camera setting) will give me the smearing problem.

[linuxsense]

In my case, I had to remove the Maximum FPS and Alarm Maximum FPS values. Setting the values to anything else (even in sync with the camera setting) will give me the smearing problem.

Yea, those options should probably be disabled by default for non 'local' feeds as they only cause problems. For IP cams I always just limit on the camera if required.