Question / Help Stream without pixelation via 2000kb/s upload doable?

[Geordy]

I was advised to open my own thread hence the quote:

Guys I need your help!
I have a max. upload of 2000 kb/s and Im having trouble getting a tolerable picture while streaming Witcher 2 to Twitch. I tried almost every combination of switches and settings out there - but pixelation is here to stay it seems :( And Im talking very noticeable pixelation.

Im streaming in a resolution of 720p@25FPS. I lowered the gamma of the game capture item a bit to save bandwidth. Ive set the graphics fidelity ingame to medium or off on most functionalities to save bandwidth. Im setting the bitrate to 1900 with a buffer of 1900, CBR activated. I tried CBR off, 1000 bitrate and buffer set to 0 in combination with the custom x264 setting "crf =" but I ended up having to set it to 28 or 29 and I still got spikes that resulted in noticeable framedrops. I even tried the "ratetol" command. I tried playing the game in 720p itself without downsizing and playing it in 1080p with downsizing by factor 1.5/Lanczos. I lowered audio to 96 bit and 44.1 kHz. I took down the CPU preset a few steps down to even just "fast". (I think that looked a bit better but acc. to task manager my 4 cores were at 100% so not an option.)

I am at a loss here. What else can I try? Do I have to live with a very poor picture? I mean 2000kb/s is certainly on the lower end of the spectrum but is it THAT bad?
(Does the crf= option do anything when CBR is activated and bitrate and buffer are set to 1900?)

 

[TheLazyBum]

CRF doesn't do anything with CBR.enabled.

A link to your stream or a video on which we can see the pixelation would be great.

The problem is, that you want to have much higher bitrates than that for perfect stream-quality.
Like your bitrate would be sufficient to do a very good 480p stream with barely any pixelation or stuff like that.

I'd recommend just try and lower the resolution to 540p and 30 fps, if you don't like it try the 616p and 30 fps.

For 720p you should have a bitrate around 2500 Kbit/s, to get a stream without much blurring, pixelation or stuttering.

You seem to aim for a more stable stream, therefore I would always go with a bit lower resolution.

 

[dping]

I was advised to open my own thread hence the quote:

540@30 would be nice for 2000 bitrate.remove the custom x264 settings as those aren't for streaming.
Also, the 0 buffer trick is NOT FOR STREAMING. that sets the bitrate to as much as the encoding resolution needs which will go way above your 2000 bitrate.

Ideal 1600bitrate 96kb audio, 44.1K audio to get a better more accurate measurement of your upload to twitch use this tool for your region and post a screen shot of the results:

http://www.teamliquid.net/forum/tech-support/478845-twitchtest-twitch-bandwidth-tester



post a logfile from the help menu after you fix those settings:

 

[Geordy]

Thank you guys for your response so far. Ok first things first:
I've made three brief test streams with audio 96 bits, 44.1 kHz, bitrate/buffer 1900/1900, CBR on, CFR on, 1080p base resolution downscaled by the factor 1.5, 1.75 and 2 respectively (from youngest to oldest), no custom x264 settings. You can find them here:
http://www.twitch.tv/testy_wenderburger/profile/past_broadcasts

Here is Twitchtest's analysis of my connection to Twitch ingestion servers:

I am using EU: Amsterdam.

And last but not least the content of the 540@30 FPS logfile:
https://gist.github.com/94936768e05578dc7049

It appears to me that even the brute force approach of lowering the resolution is not fixing the pixelation.

Edit: Well there is obviously something going on with Twitchtest. Im running it in a Sandbox with Inet access. Could that be a problem?

 

[Geordy]

Bump

It seems TwitchTest requires admin access to run properly? Judging from the files Twitchtest put into the Sandbox there are a lot of changes it tries to make to the registry.
Anyway the log provided apparently has all three test streams covered. Excellent. I wonder why acc. to the log single streams ended and restarted in the turn of seconds which it clearly didnt?

 

[H4ndy]

1900 bitrate is too high for your connection, you need to add your audio bitrate to this and you have at most 1920~ upload available.

Set it to something like 1750 which will add to around 1850 with audio. Operating so close to your limit requires that you do nothing else on your connection while streaming.

 

[Geordy]

Thanks for the response! I will run another test with 1750/1750. And here I thought the bitrate you specify covers the whole package, video and audio, that OBS is allowed to grab.

Anyway this helps only with framedrops, right? What about the pixelation?

 

[H4ndy]

Pixelation is only a bitrate to resolution+fps ratio problem.
If you have a powerful CPU you chose a slower CPU preset (e.g. Fast, Medium) which will help a bit.

 

[TheLazyBum]

I would recommend the presets veryfast, fast or slow, because these give "best" quality/performance ratio.
Depends in your CPU and the resolution/fps you will choose.