Question / Help Webcam Latency Question - Logitech C910 & C920

[Zabermoul]

I'm sorry if people have already asked about this issue. I did a search and couldn't find an answer.

When I stream I'm having an issue with my Logitech C910. I have set it to 1280 x 720 @ 30 FPS, Checked "Use Output Format" and set it to RGB24. Deinterlacing has not been enabled and the audio from the webcam has been disabled.

With these settings I get a delay on my webcam at about 250 ms to 300 ms. The only way I can try to counter this is by setting a delay on my mic @ 250 ms. This option leaves me with another problem... As there is no way to set a delay for the system sound coming from my pc it will be ahead with 250 ms to 300 ms of my microphone.

Is there any fix to counter the delay on the webcam? Or is there a way to enable some sort of delay on my system audio? Or a general fix to sort this out?

I know I can set the entire stream to have a delay but I can't set my webcam to a negative ms.

Thanks in advance for any help on this topic and once again sorry if someone else has covered this before on the forums.

Kind regards
-Zabermoul

 

[Lain]

Re: Webcam Latency Question - Logitech C910

RGB24 can cause this, you might want to try the other two instead, whichever ends up being faster. Also, if you have audio delay, you may want to try the latest test build with it.

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

Thank you for the quick reply Jim ;)

I don't have any audio delay. It's the webcam picture itself that has a delay. So the only way to get my mic in sync with the webcam is to set a delay on my mic.

I will do some more testing with the webcam settings and see if I can get it to run without any delay. I will return with the results when I have tested every possible option.

 

[Lain]

Re: Webcam Latency Question - Logitech C910

Ah okay then you don't need to use the test build for now -- the C910 should work fine otherwise, I have one myself. Try the other two output formats and see which one is better, I have no delay out of my C920 personally.

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

I only have 2 options. RGB24 and I420. I420 has more delay on it then RGB24 has. I even tried to disable the option just for fun but that didn't solve the issue either.

This is really weird though... I have seen others on Yahoo forums and other places trying to solve the exact same issue.
I will check the drivers and see if any new drivers has been released and return after I have tested that ;)

Once again thanks for the quick response :D Keep up the good work Jim :)

 

[Lain]

Re: Webcam Latency Question - Logitech C910

It might be drivers, not entirely sure. It feels unusual because on my system I get no delay out of it. Not sure if this is a difference between the C920 and C910, but I'm pretty sure they should be pretty much identical.

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

I checked up on the drivers and the latest drivers was from October 2012.

I think there is a difference between the C910 and C920. Like I said earlier... I have seen other forum posts when I did a google search for this issue and there was quite a few about the C910 and OBS.

Just out of curiosity... How come there isn't an ability to put a negative value on the webcam delay? Lets say you put a 300 ms delay on the entire stream. All people would have to do was set the webcam to a -300 ms.
That would kinda foolproof the program for people who run into these issues with current and future devices.

Its probably hard as hell to code though. But if there was a value that said "Stream Delay = True, Amout = x, If True allow negative value of same amount on other devices". Probably sounds easier said then done lol

Anyways... I think after all this testing the verdict is gonna be a new webcam... Again :(

Once again thanks for the quick response. Keep up the good work Jim :D You have made on hell of a good job on OBS! :D

 

[dodgepong]

Re: Webcam Latency Question - Logitech C910

Try lowering your webcam resolution more and see if that helps with latency.

Just out of curiosity... How come there isn't an ability to put a negative value on the webcam delay? Lets say you put a 300 ms delay on the entire stream. All people would have to do was set the webcam to a -300 ms.

Because that would require the ability for the webcam to see 300ms into the future, which modern technology hasn't been able to accomplish yet.

 

[FerretBomb]

Re: Webcam Latency Question - Logitech C910

Just chiming in, I have a c920 and get a consistent 300ms delay as well (in OBS only), using I420 mode at 1920x1080 (as I cast in 1080p and do fullscreen-cam), with the cam being the only thing on the USB host controller. I've had to set a 300ms mic delay as well. Only down side being that I can't sing along with music, and I react to things about a half-second late on-screen. Lowering resolution does decrease this delay.
Jim, what are you using as settings to get no delay on the c920 in OBS? May be able to set up a test case and whittle down differences.

This may become a problem for me as well, as I wanted to run my system audio through my mixing board and feed it back into OBS that way... but in doing so, it would incur that same 300ms delay, putting the system audio and video out of sync . Using the mic delay and native desktop audio capture works for the time being, but it's a little disappointing that I can't use my equipment to its fullest, without the ability to time-shift the webcam back (eg: time-shift/delay everything else forward 300ms). I understand the technical limitations that prevent this from being feasible.

I do have to wonder though... what kind of performance hit would it incur to buffer off, say, 1-2 seconds of video to system RAM, to allow this? I know it'd be significantly slower than just doing everything in VRAM, and possibly bottleneck the video card bus when loading new textures (but seriously, who isn't running their video card in PCIe x16 if they aren't running in SLI?). I mean, I've got a 30GB RAMdrive (most days) that's doing very little for the most part, so throwing that particular resource at the problem wouldn't be an issue.

 

[dodgepong]

Re: Webcam Latency Question - Logitech C910

The delay is because the camera has an onboard encoder and is encoding 1080p video to be able to fit it over a USB 2.0 wire. It's the same issue that USB capture cards have. It has to be encoded on the camera and decoded on the computer. They just use a very efficient method of encoding to reduce the delay to as low as possible for webcam use. Higher resolution means longer encoding/deciding times. 300ms delay is fine for use in video calls, though, which is what webcams are intended for.

 

[sendblink23]

Re: Webcam Latency Question - Logitech C910

It might be drivers, not entirely sure. It feels unusual because on my system I get no delay out of it. Not sure if this is a difference between the C920 and C910, but I'm pretty sure they should be pretty much identical.

I wonder how don't you have a delay, on my c920 I have to use the same 300ms delay as FerretBomb
No matter the cam resolution(I even only use 320x180) or output format and it always needs the delay

 

[Lain]

Re: Webcam Latency Question - Logitech C910

Yea, I don't quite know. I just use it on all default settings, and I even have it plugged into USB 2.0 as well. Sometimes plugging it into USB 3.0 can help, try it out.

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

Because that would require the ability for the webcam to see 300ms into the future, which modern technology hasn't been able to accomplish yet.

Not entirely true... If the entire stream is delayed by 300 ms and you set the webcam at -300 ms you would cancel the delay on the webcam = It would not have to see into the future ;) See... Basic math works wonders hehe :D But I get what you are saying though ;) I have tried to lower the resolution but then the webcam glitches and causes OBS to crash. I even tried to re-install the drivers to see if that would fix anything but it didn't...

Now that I see others are having the same issue with the C920 as well I'm a little bummed out. I just ordered a C920 to replace my C910.

Oh and by the way Jim... There is a very significant difference between the C910 and C920. The C910 uses the CPU for processing and the C920 has an in build hardware encoder in it. I had hoped that the C910 had the delay due to that but since I see others with the C920 has the exact same issue as well I'm starting to wonder.

Maybe I should cancel my order before it is too late and see what other people has to say in terms of their C910 and C920.

 

[dodgepong]

Re: Webcam Latency Question - Logitech C910

That's not the way stream delay works in OBS. If you are delaying the whole stream, it's already all captured and encoded, and then stored in RAM. You won't be encoding everything but the webcam, then overlaying the webcam, and then encoding it all over again. It all has to be captured before encode time. Which means your webcam would have to see into the future for -300ms of offset.

 

[FerretBomb]

Re: Webcam Latency Question - Logitech C910

I do have to wonder if it would be feasible to buffer un-compressed layered video into the system RAM... I doubt that 1-2 seconds would eat more than a gig or two of RAM, but don't know if the bus would end up flooded at that point just moving the data between VRAM and RAM.

I'm curious how plugging it into a USB 3.0 port would help? It's a USB 2.0 device; Logitech bills it as '3.0 compatible' only because 3.0 is backward-compatible with 2.0... it doesn't have the extra pins required to take advantage of 3.0 speeds. And some people have reported odd visual artifacting (color bars, blocking, etc) when plugged into a 3.0 port that disappear when plugged into a 2.0 port.

Are you running at 1920x1080 Jim, in I420 output mode? Or no specified output resolution/mode? I'd like to track this down if possible, as if it can be fixed, it'd be an irritation out of the way and would open up a lot more options for configuration.

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

FerretBomb I think I have found a few things that can fix the issue. I decided to let my order of the C920 go through and did some further testing.

Please let me know if this solves the latency issue! This might fix the issue with the C910 as well.

In OBS go to "Global Sources" (if you have your webcam in there).
Click on your webcam and go into "Properties".
Click "Configure" (At the very top)

This will open the Logitech HD Pro Webcam C920 configuration.
In the first tab (Webcam Control) Disable "Follow My Face" and disable "Auto Focus".
In the second tab (Advanced Settings) Disable "RightLight". Also disable "Auto" in "Gain" and the same for "White Balance".

After that play with the "Contrast", "Color Intensity" and so on until you are happy with how it looks.

Explanation:
I found that when all those settings are enabled it requires so much more to process the picture and that in itself could be the cause of the latency issue we have been seeing.

Let me know if this fixed the issue for any of you guys. I will return and write some more if I find any more issues.

-Zabermoul

 

[FerretBomb]

Re: Webcam Latency Question - Logitech C910

Nope, I've had all that... er... 'helpful' stuff turned off since day one.

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

Nope, I've had all that... er... 'helpful' stuff turned off since day one.

Alright. I will do some testing and see how well my stream performs. I will report back when I know more ;)

Oh... Almost forgot! I installed an older driver as well. Driver version 2.40.845.0. Google that one and give it a try. I'm also using Output Format MJPG. Just in case you wanted to give it a go with the settings I'm currently trying :)

 

[FerretBomb]

Re: Webcam Latency Question - Logitech C910

I may try the older driver, but I moved to I420 from MJPG originally; the latter seemed to provide an erratic delay and I420 mode at least gives a consistent one.

What kind of delay are you actually getting, at current?

 

[Zabermoul]

Re: Webcam Latency Question - Logitech C910

I have now tested every possible option and the C920 will ALWAYS have a delay on it... I ran about 20+ short tests where I would clap a few times to see if the audio would line up and it never did.

The tests had the webcam delayed from 122 ms to 165 ms using all kinds of various settings. Using the same settings 2 - 3 times in a row would give different results as well.

Now that everything has been tested so much I can say with ease that the problem is within OBS. How it's happening and what is causing it I'm not sure about.