Streaming with ffmpeg kills my internet connection

0
votes

Im trying to stream with ffmpeg to twitch.tv. Basically it works, but in time, my internet connection get knock-outed. I mean, if I run an infinite ping, I stop getting replies. Or I just cant browse on the internet.

Basically I used it like this:

ffmpeg -f dshow -i video="screen-capture-recorder" -vcodec libx264 -r 25 -pix_fmt yuv420p -preset ultrafast -f flv "rtmp://live.twitch.tv/app/live_****************"

it works for minutes.

But when I modify the command:

ffmpeg -rtbufsize 1500M -f dshow -i video="screen-capture-recorder" -vcodec libx264 -r 25 -pix_fmt yuv420p -preset ultrafast -f flv "rtmp://live.twitch.tv/app/live*******************"

it just wont send anything and floods my connection (I mean, connection breaks)

Of course, it sends me tons of "real-time buffer [screen-capture-recorder] [video input] too full or near too full (100% of size: 1500000000 [rtbufsize parameter])! frame dropped!" messages.

Cant it be set to adapt to my internet bandwidth, or at least dont kill my connection?

2
videoffmpeg
"Cant it be set to adapt to my internet bandwidth" As far as this goes, you can adapt your uplink, but you shouldn't logically need to adapt your downlink if you are the one streaming. You could try using Resource Monitor on Windows and/or Wireshark to get a better idea of what's going on. - Æðelstan
Visit speedtest.net. What is your resulting upload number? What bitrate is your output from ffmpeg? It will show it during encoding. - llogan
5.57 Mbps. What to set for ffmpeg? - John Smith
Answers take some effort. A comment would be appreciated. - Jorge Fuentes González

2 Answers

1
votes

You should add -b:v 2500k -maxrate:v 2500k -minrate:v 2500k (Before -f flv) wich forces bitrate to 2.5 Mbps. Check your current upload and twist the values to fit it. I recommend not filling 100% of upload speed with this.

Also -b:a will force audio bitreate. 96k is a good value.

1
votes

Have you tried uploading large files (simulating continuous streaming)? I have the exact same problem but then noticed it happens with all uploads, not just streaming. I suspect the cheap (Speedtouch) modem I got with my ADSL simply overheats and shuts down. Same thing does not happen when downloading btw.