Linux stream to youtube via libav. (for distributions utilizing Aptitude)

stream.sh

#! /bin/bash

INRES="1366x768"
OUTRES="1366x768"
VBR="1800k"
FPS="30" # fps
QUAL="slow"
STREAM_KEY=$(cat ~/bin/youtube_key)

if [ $(dpkg-query -W -f='${Status}' libav-tools 2>/dev/null | grep -c "ok installed") -eq 0 ];
then
  echo "Need to install libav-tools."
  sudo apt-get update;
  sudo apt-get install -y libav-tools;
fi

avconv \
-f x11grab -s $INRES -r "$FPS" -i :0.0 \
-f alsa -ac 2 -i pulse \
-vcodec libx264 -pix_fmt yuv420p -preset $QUAL -r $FPS -g $(($FPS * 2)) -b:v $VBR \
-acodec libmp3lame -ar 44100 -threads 4 -qscale 3 -b:a 712000 -bufsize 512k \
-f flv "rtmp://a.rtmp.youtube.com/live2/$STREAM_KEY"