youtube-dl

youtube-dl --autonumber-size 3 --ignore-errors -o "%(title)s.%(ext)s" --yes-playlist PLAYLIST

youtube-dl --autonumber-size 3 -o "%(autonumber)s -- %(title)s.%(ext)s" --yes-playlist PLAYLIST

youtube-dl --autonumber-size 3 -o "%(autonumber)s -- %(title)s -- %(upload_date)s.%(ext)s" --yes-playlist --playlist-reverse PLAYLIST

-F to query video formats
-f to choose quality from -F (also can be "best" or "worst")

youtube-dl readme

_________________________________________
# FLV, AAC audio
ffmpeg -i in.flv -q 1 -map a out.mp3
# Apply max noclip gain
mp3gain -r -k -m 10 out.mp3

# FLV, MP3 audio
ffmpeg -i in.flv -c copy -map a out.mp3

# MP3 file
ffmpeg -i in.mp3 -c copy -map a out.mp3

# WAV source
ffmpeg -i in.wav -b:a 320k out.mp3

# Flac source
ffmpeg -i in.flac -b:a 320k out.mp3
_________________________________________

ffmpeg -i filename.mp4 filename.mp3

ffmpeg -i video.mp4 -b:a 192K -vn music.mp3