Bug Report New Webcam causes growing delay

[KOKOStern]

On my crappy cam, I use RGB24 (default) and it works perfectly.

Using RGB24 or MJPG on the C920 gets super delay.

Using I420 seems to be the best course of action, and after 2 hours it still seems pretty good. I do feel however, that there's this tiny delay that makes the video look weird.

When I talk and look at the screen for my old camera, it seems fluent and on point, looking at the new camera, it seems just a tiny bit off, like I placed voice-over and it's a bit in delay. This seems to be consistent however, so it doesn't get worse.

In any case, the delay in the other output formats indicates there's still a problem anyways. I don't really know what else to do.

Jim what are the exact settings you use when recording? I'm talking about everything from the device itself to OBS settings while recording. I wanna check using your exact settings (you said it works for you) and see if it'll change anything. Say anything, video, audio, advanced, and specific camera stuff, even exposure. It might help us find the problem, and if I change everything and the problem persists, we'll know it's something with drivers.

 

[Lain]

Right now I just have my resolution lowered somewhat, at 30fps, but that's honestly it

 

[KOKOStern]

Anything here you see that's different? Should be changed? Anything? =\

Encoding
QB: 10
Max Bitrate / Buffer Size: 4000
Codec: AAC
Bitrate: 192

Broadcast Settings
File Output Only

Video
Custom: 1280x720
Resolution Downscale: None
FPS: 30
Disable Aero at startup: Unchecked

Audio
Playback: Default
Microphone: My Logitech crap USB
Mic Boost: 1
Mic Time Offset: 0

Advanced
Use Multithreaded Optimizations: Checked
Process Priority Optimizations: Normal
CPU Preset: veryfast
Force audio to sync to video time: Checked
All other checkboxes unchecked
Latency tuning factor: 20

 

[Lain]

I just did a local file test of my webcam for like hours and it never went off sync. now I will note that the general image display is off-sync by like 50-100ms, but that was easily fixable by simply adjusting the mic time. I had the resolution set to a lower resolution just because I didn't want it to take up the entire screen but that was the only real setting I messed with.

but outside of that, my c920 never went further out of sync or anything. it was always displaying at the same rate. I'm on an i5 2500k so our computer setup should be fairly similar.

 

[mainpmf]

My c920 has massive de-sync as well, you should look further into this

 

[Grimio]

Can you try other USB ports and report back, please? I'm curious about the impact of the USB controller.

 

[Lain]

I tested my c920 for hours and didn't get a desync. I'm not specifically sure how I can further look into this, I mean I just don't understand why I'm not getting this and you guys are.

I mean when I have it working what am I supposed to do? Am I supposed to try to break it so I can simulate your problem? I can't seem to do it, every test I've done has been successful and I have the same exact device.

Seriously, same exact device, yet no problem. I mean I am seriously at a loss here.

 

[mainpmf]

Can you try other USB ports and report back, please? I'm curious about the impact of the USB controller.

I've tried couple of ports (2.0 and 3.0 usb) problem's still there. Before i've never noticed the de-sync but now it works for a couple of seconds then it starts messing up

 

[Grimio]

Do you have any other USB devices plugged in besides the cam, mouse and keyboard?

 

[KOKOStern]

Jim how exactly to fix the small delay? That might be what's bothering me.

What settings to change exactly?

 

[Lain]

settings -> audio -> mic time offset (milliseconds)

this can be adjusted even while streaming. change the value, hit apply, and the delay will change while streaming.

 

[KOKOStern]

I tampered a bit with it but doesn't really help =\

 

[Lain]

why specifically wouldn't it help, if you don't mind me asking? you can delay your mic audio to play up to 3 seconds later on the stream, that should be more than enough for you to find the right value

 

[KOKOStern]

Even if I get it perfect, there's more then my camera and my mic on the stream.

Can I delay everything else as well? It's not really a solution...

 

[Grimio]

I might have another wild guess on what could cause or at least influence this.
DPC latency.

Try out this guide and see if it helps:
http://blog.tune-up.com/windows-insight ... cy-issues/

 

[KOKOStern]

About 200 ms seem to put my mic and camera in a pretty perfect sync, but any sound that comes out of my speakers is obviously messed up. I can't stream anything other then Camera / Mic, and I stream games so this isn't a solution.

@Grimio -I got the DPC Latency Checker, put on a game and recorded same time, I still stay well below the green zone. Nice try but sadly no go :(.

 

[Lain]

"any sound that comes out of my speakers is obviously messed up" ..could you be more specific if possible? I thought this topic was generally about webcam sync with the mic

 

[KOKOStern]

We've established my Cam is off sync, it's behind everything else that's happening.

If I use 200 mic sync, then my mic is 200ms behind everything as well, and so it's synced with my camera.

If we stop here, everything is fine, but what if I also record a game. That game has video and sound, and it's all recorded in time 0, without the 200 delay that my camera and microphone has.

Let's say I play a song from youtube and sing it as well (hypothetically), you'll hear me singing 200ms after hearing the song being played from my speakers.

 

[KOKOStern]

So I've been searching the net for anything that might help as this issue still exists.

http://www.youtube.com/watch?v=Q66cZe-X1GQ

This guys uses VLC to impose a caching delay on the webcam itself.

If there would be an option to set a delay for each item in a scene, that would allow users to mess with whatever setting they have in order to make things sync up - as long as there's no growing delay (which as far as we know you've successfully eliminated at this point).

Might this be possible?

 

[Lain]

Delaying video itself is not a simple task. I don't have anything implemented to delay image updates, because it would mean that the video has to be buffered, I just don't have anything written for that at the moment, and may not for some time