Question / Help I need a way to LIMIT my bitrate to 4000kbs

[miloooo]

I use CBR set to 4Mb/s my upload speed is 5Mbs, my ISP shapes my connection when I go above that but I dont want to lose the quality by lowering the bitrate. I was streaming today and my bitrate was spiking to 10Mbs and therefor was being shaped to 2.2Mbs. Is there a setting or something I'm missing here? I don't want the bitrate to go above 4000 at all.

please help, thanks.

Edit - the shaping was causing me to drop almost 44% frames. I contacted my ISP which is small and local, they uncapped my upload speed for the time being but I need to find a way to cap it to 4000 so I don't get those huge spikes otherwise when they re-cap that upload the same thing will more than likely be happening.

 

[c3r1c3]

Unless you post a log it'll be impossible to help you.

 

[miloooo]

I think this is the log file. I had to restart my stream a few times. Any help would be greatly appreciated, thanks.

 

[miloooo]

here are all the logs for that day. thanks friends.

 

[c3r1c3]

1. (Nothing to do with your current issue, just something in general) The Windows 10 CU added a new Game Mode option which causes issues more often than it helps. It is recommended to disable it when using OBS. See here for how to disable: https://www.windowscentral.com/how-enable-disable-game-mode-windows-10-creators-update

2. My personal experience has been that NVENC tends to spike more-often and to higher bitrates than x264. So I would recommend that you use x264 instead of NVENC as your encoder.

3. If you choose to stay with NVENC then you'll have to push your listed bitrate lower (then x264) and you'll still have spikes that go over the 4Mb limit you mentioned...and all at the low bitrate quality suck that is NVENC. Best to go with x264 in all cases.

4. In general you'll want to give yourself some headroom if your upper bitrate limit is strict. The best way to do that is lower your fps and resolution in OBS so you can lower the bitrate without impacting the stream's quality too much. So I would target a bitrate of 3000 (if your 4Mb limit is very strict) to 3500 (if your 4Mb limit is more practical then strict) for streaming using x264.

 

[goldenh]

I use the third party program https://alternativeto.net/software/netbalancer/ to manage each program's bandwidth usage. This isn't just good for OBS, but also for skype. Keep in mind that this will actually cap your bandwidth - it'll be exactly like streaming on lower bandwidth, though potentially more stable. So if you stream at 4 mbps, and tell netlimiter 4mbs, it'll probably have bad results... but you can use it to control peaking pretty well if you give it say only 50% more than you need... or ideally, just under whatever your ISP tells you is the cutoff.

 

[Boildown]

You can increase how predicable your outgoing stream bitrate is by decreasing the buffer size. Unfortunately the Use Custom Buffer Size checkbox is only available for x264, not NVEnc.

If you were using x264, you could set it to 4000kbps but set the buffer to, say, half that, 2000kbps. The problem is that you'll still exceed 4000kbps sometimes. Even a "constant" bitrate stream isn't really that constant. So if I were you I'd set a bitrate well below that, maybe 3000kbps with a 1500kbps buffer. You will need to find the best values experimentally, yourself.

Note that using a buffer smaller than the default will have a negative effect on video quality (conversely having it higher will improve it), especially in moments of high motion.

 

[R1CH]

Using low latency mode will achieve a similar effect.