ffmpeg memo

• Remove metadata
  avconv -i in.mp4 -map_metadata -1 -c:v copy -c:a copy out.mp4
• To create a Camtasia version 8.6 compatible mp3 file
  ffmpeg -i input.mp3 -codec:a libmp3lame -b:a 192k -write_xing 0 -id3v2_version 0 output.mp3