Increasing podcast tempo (playback speed) with Mplayer and Lame

The following commands will re-encode an mp3 file at a faster speed without increasing the pitch and making it sound like a chipmunk. How this actually works is pretty neat.

mplayer -vo null -vc null \
        -speed 1.33 \
        -af scaletempo,volume=0,resample=44100:0:1 \
        -ao pcm:fast:waveheader:file=temp.wav \
        source.mp3
lame -b 64 --resample 22.05 temp.wav faster.mp3

It will also set the bitrate to 64kbit which was for compatibility with my old player and to reduce the filesize for some podcasts which are unnecessarily big.

There should be a way to use mkfifo instead of temp.wav, and run the mplayer process and lame at the same time, I'll update this when I figure it out.

Update: The above method broke after upgrading to Ubuntu 11.10 (one or both of mplayer or lame changed something I suspect...), so I swapped it out for the simpler and better SoX:

sox --show-progress --norm source.mp3 dest.mp3 \
    tempo -s 1.33 channels 1 rate 22050

This version is easier to understand, faster, doesn't leave need a temp file and also, as a bonus, normalizes the audio to prevent clipping and not hurt my ears.

abcde — A Better CD Encoder

ABCDE is a nice CD ripper/encoder utility for Linux.

It's all nice and automatic, and I managed to configure it to suit my mp3 management style pretty quickly. My .abcde.conf file:

OUTPUTDIR=/home/tom/Desktop
OUTPUTTYPE=mp3
LAMEOPTS='-h -b 224'
ACTIONS=default,playlist
OUTPUTFORMAT='${ARTISTFILE}/${ARTISTFILE} - ${TRACKFILE}'
VAOUTPUTFORMAT='Various/${ARTISTFILE} - ${TRACKFILE}'
PLAYLISTFORMAT='${ARTISTFILE}/${ARTISTFILE} - ${ALBUMFILE}.m3u'
VAPLAYLISTFORMAT='Various/Various - ${ALBUMFILE}.m3u'

That sets it up to rip to mp3s at 224kbs and write out a playlist file. The files are saved onto the desktop to test before I move them to my mp3 folder in the "Artist/Artist - Track.mp3" name format that I prefer.

mungefilename () {
 echo "$@" | sed s,:,\ --\ ,g | sed s,/,\ --\ ,g | tr \* + | tr -d \"\?\[:cntrl:\]
}

I also changed the filename processing so that colons and forward slashes are converted to double dashes (my scripts use single dashes to split the artist from the track title.) And I don't convert spaces to underscores and I leave single quotes alone.

MAXPROCS=2

Runs an encoder process on each core so it goes super fast.

I run it from an icon on the desktop with the following command line:

gnome-terminal -x abcde

Update: I just discovered the "gnome-terminal -x" is unnecessary, there's an option to launch an application in a terminal window automatically...