Question / Help corruption in incoming webcam streams ONLY in OBS

[Talkiet]

I've got a horribly frustrating issue. When I have more than one source (RTSP from some cheap 1080P cameras) I am getting image corruption (tearing, colour squares etc) regularly. Here's a link to a large image of the OBS screen:

http://neilnz.com/stuff/obs_issue.jpg

And here's a small version:

Typical image issues are highlighted on the preview screen - note that they also occur in the output.

- Machine is an i7 - 2600K with 16GB RAM.
- CPU is well under 100%, I have tried NVenc to get CPU usage down to under 25% and still the same issues.
- Testing the RTSP streams from other software (ONVIF Device manager, VLC, my NVR interface etc) shows perfect streams with no corruption.
- I have tried setting "use hardware decoding when available" on and off, no change observed.
- I have rebooted the PC, updated drivers, installed different h.264 codecs, no changes observed.
- I've tried changing the cameras output bitrate up and down, changing from VBR to CBR, changing the framerate from 25 to 30 and back., No changes observed.
- I have checked network traffic, it's under 15Mbps to this machine (and as I say, the same streams are perfect under different software).
- Dropped frames stay at zero (output is faithfully the same as preview)
- I've tried using the RTSP streams from the NVR instead of the cameras individually, no change.

I've looked through the forums and found a lot of almost related issues but most refer to tearing or issues with game streaming that come from vsync issues, and one or 2 unresolved posts that seem similar.

It's very frustrating because it looks like OBS is unable to always accurately decode the RTSP input streams. It certainly seems worse with multiple streams (ie. one stream is fine, minor issues with 2 streams, worse with 3 and bad with 4).

What else could I try to get OBS to be able to decode these error free streams?

CHeers - Neil G

 

[Talkiet]

Update - have tried the 32bit version of OBS as well and same issues occur.

Cheers - N

 

[Talkiet]

Further confusing update.

I replaced one of the camera sources with a VLC source which gives different problems (huge pauses of up to several seconds, grey screens for a few seconds at a time - generally horrible performance) BUT with VLC running in another window on the same machine VLC itself is happily playing the same stream perfectly.

This is a problem in OBS itself isn't it?

Cheers - N

 

[Talkiet]

Have attached a most current log file. Reading through it myself now...

 

[Claudio]

Same problem as Talkiet, but in OBS Linux.. so, yes, it seems to be a OBS problem.

I got the same h.264 artifacts when a foscam 1080p ip camera is set up as media source for OBS.
But NO PROBLEM with the same stream, in VLC or FFPLAY (ffmpeg media player).

So I guess something is bad in OBS handling this sources.

 

[Chuckaholic]

I know this post is really old but I'm having this same issue. Doing a live stream and using security cams to show fountains outside and an overview of an arena during cuts and using a uTap with 4K cam for main shots. 4K cam looks great, as does playing mp4 files. The rtsp cams are almost unusable. Blue Iris software shows a perfect picture from these cams but OBS had lots of corruption. VLC also has corruption but it's different and more pausing than tiling.
OBS 21.3.0 64 bit
Laptop- MSI GE72
Core i7-6700HQ @ 2.6Gz
16GB RAM
Nvidia GeForce GTX 970M
Win10 Pro 64 1903

 

[javidos]

I have the same trouble with several security cams...

 

[Tim Husted]

I am observing the same issues when running OBS 64bit 24.0.3 on Windows 10 - input RTSP stream runs great on VLC, and it runs great on OBS in the preview but when I send it out on the live stream then both the preview and the actual output stream are full of bitrate artifacts. Same OBS system using USB input camera and local MP4 files works great.

 

[Tim Husted]

after considerable testing, I was able to get my issue resolved. Ultimately it was a bit error rate on the switch uplink that the OBS computer and streaming camera was on. The fact that VLC shows the image in what appeared to be artifact free does appear to be how the stream processing modules work between OBS and VLC. To fix my problem, I created a dedicated layer 2 network between the OBS computer and the streaming camera, so no router interface to go across, and then the OBS computer has a dedicated internet facing interface that is used to broadcast directly to Facebook Live and QoS is applied to guarantee my bandwidth through my network. Eventually I will fix the uplink cable to get rid of the errors but its an old building with poor access to cabling pathways. Anyway, this post is to hopefully help anyone else having the issues - I am on OBS 64bit 24.0.3 and Windows 10 on a SSD and 8gb ram and dedicated NVidia GPU with I7 processor. So, the diagnostic that VLC works but OBS doesn't isn't as clear and it originally appeared - in my particular case (always check layer 1 issues...)