Extract mp3 from .ts files
ffmpeg -i inputfile -f mp3 -acodec mp3 -ab 128k -ar 44100 -vn outputfile.mp3
http://quartz-net.co.uk/quartzwiki/index.php/TS_convert_using_ffmpeg#Audio_conversion
Down scale video
ffmpeg -i inputfile -s hd720 -c:v libx264 -crf 23 -c:a aac -strict -2 output.mp4 http://askubuntu.com/a/99648 