Question / Help Input Needed

[slammedmkv]

I have a few questions that hopefully some of you may know the answers for. I have looked through the forums but cant find a definitive answer. So for my setup I have a two pc setup the gaming rig specs really dont matter for this but Im getting video from the gaming computer to the streaming computer with a Avermedia Live Gamer HD and audio and mic is ran through a mixer and then through line in to the streaming computer.

Streaming computer specs
AMD FX 6450 6 core at 3.9
8 Gig ram
580 GTX
Net - 105 down 10 up

Now for the first question I am wanting to stream at 720 @60fps. I am gaming at 1080p, so to stream at true 60fps with the avermedia through OBS do I need to set scene size to 720p and under the avermedia source properties do i set it at 1280x720 at 60 fps because the avermedia does not do 1080 @60fps.

Next question is quality wise is it better to have a scene size of 1080p and downscale to 720p in OBS with Lanczos filter or to have the scene size at 720p and not downscale in OBS?

Lastly I am a stickler for production quality so Im trying to run as I said above 720p at 60 with a 3500 bitrate now I could raise my bitrate up alot more and make it look better but Im just starting off so I would like people to be able to watch my stream and I still get people saying my stream buffers and lags sometime but I am not dropping frames. So this is more of a trifecta of a question. For some reason my fps in OBS drops from 60 to the 45-59 range when in a faster preset. Is my cpu really not able to handle it there is nothing else going on in the computer its a dedicated streaming computer. Also would dropping my bitrate from 3500 to 3000 cut quality by much because even set at 3500 my bitrate is all over the place jumping up to 4200.

Thank you for taking the time to read this and provide any input you may have

 

[Tyraxiss]

Ok, I'll try and tackle your questions one at a time. I personally don't have an Avermedia Live Gamer but from what I understand with it it has build in scaling so even if the main gaming monitor is set at 1080p60 you can output the source to 720p60 as long as your not using the Recentral software to record.

And Yes, the Avermedia Lives down-scaling will be better then OBS down scaling even when using Lanczos. While OBS down-scaling is pretty dang good, the Avermedia's build in down scaling looks better from the samples I've seen. And just for what it's worth, the difference between bicubic and Lanczos is mostly in how much sharpening it does.
So I suggest setting up your OBS base resolution to 720p and down-scaling the original source from the Avermedia Live Gamer.

On to the Production Quality question.
For 720p60 I'd suggest 2500 to 3000 bitrate at most. The video stuttering and what not that your viewer are complaining about has more to do with their internet speeds and system spec's then it does with yours. Which is why Twitch.TV has recommended rates as a guideline. I use 2000 for 720p30 and have a good quality and no stuttering at all. But I also use a CFR=18 under advanced and added into the custom x264 encoder settings area.

And on the FPS question.
From what I understand OBS uses a veritable frame rate, what that means is that even though you set it at 60 FPS if there's not much going on in game (or any other Source Capture) it will automatically lower frame rates to decrease overall bandwidth usage. I could be wrong here so this one you might want to check into more.

I have an AMD Phenom X2 965 CPU and have done some 720p60 streaming just to see if my system could handle it and it did with a few spots dropping in the video down to 49 FPS in very low action area but as soon as action picked up so did the frame rates.

 

[slammedmkv]

Tyraxiss,

Thanks for the lengthy response, so I will just start setting my scene to 720p and setting in the avermedia source properties to 720 at 60fps.

As for the production side of things I think Im gonna try 3000 bitrate and see where that takes me. I figured it was on their end because when I go back and watch the VODs its pretty smooth.

The FPS part is what really is confusing me because on veryfast im pretty smooth at 60 and will drop down if im flying around in bf4 trying to drop the frames, however on faster im getting the skipping frames which is crazy because its basically a 6 core dedicated cpu. The reason i want to set it to faster is to get alittle better quality at the lower bitrate.

 

[Tyraxiss]

Gotcha, all things considered. The CPU usage between veryfast and faster is quit big so it's possible that your system just can't handle it at 60 FPS on faster. My suggestion is to use veryfast and under advanced settings try a custom setting of crf=18 and do a local recording test to see how it looks at 2500 kb/s then do the same for 3000 kb/s.

I noticed a big improvement in quality using the crf=18 compared to not having it enabled. Keep in mind I'm streaming 720p30 at 2000 kb/s though. So I'm playing the game and OBS is encoding on the same computer that's running a AMD Phenom x2 965.

Even so it looks pretty good from what I can see. Could be better of course but I just don't have the money to buy a capture card to use with my other lower end computer. Wish I could because that would definitely improve the streams quality.

Maybe at some point I'll get enough donations or something to pick one up :P

Edit to correct typo's. I meant crf=18 not cfr=18

 

[slammedmkv]

sorry for my stupidity here but your talking about the x264 setting just put in there cfr=18? what is that actually doing? telling it to run at a frame rate of 18? mind if i get a link of your twitch so i can check out your quality and show my support lol

 

[Tyraxiss]

Yeah sorry, I meant to type crf=18 not cfr=18. The cfr=18 basically stands for Constant Rate Factor. Heres a Link to a guide that explains it way better then I possible could. http://slhck.info/articles/crf.

As far as my twitch.tv account, http://www.twitch.tv/tyraxiss I'm new to twitch.tv so only have one past show on right now but will be doing more. And keep in mind I'm doing the streaming on a very old PC lol.

 

[slammedmkv]

so from what i read the crf is for local recording and has nothing to do with streaming quality or am i wrong in that aswell

 

[Tyraxiss]

No, crf will also effect streaming quality also.