[MPlayer-users] Re: play only first 30 seconds of a song

[adland]

> Wow!  That's a bit of work.  I never would have guessed it would be so
> difficult just to get the first 30 seconds of an mp3 file.  Thanks for
> your scripts!  I will give them a try...

I had tried a few other ideas previously with limited success

mplayer has options like -edl editlist but this only works if you have video

you could also use something like -frames to limit playback to X num frames
(again video is required) also it did not give good control over length
for resulting audio file

not a problem because -audiofile allows us to play a mp3 file as audio track 
for a seperate video

idea was to use length * frames _per_second = X

FYI: get value for frames per second in video file
mplayer -frames 0 -identify file.avi

Also just thought about this
you might could use the unix command dd to read the bytes from FIFO.
see man dd for more info

mkfifo MYFIFO
mplayer -ao pcm -aofile MYFIFO -vo null -vc dummy song.mp3 &
dd if=MYFIFO of=test.wav bs=1 count=X
rm MYFIFO
killall -9 mplayer

where X = 44 bytes for header + channels * bytes per sample * rate * seconds
or 44 + 2 * 2 * 44100 * 30 for 30 secs CD audio

my python program does however modify the filelength written in the wave header
to match new length for smaller duration file

good luck