Cutting Short, splitting or truncating mp3 files…
from the command line in linux… or generating them from Wavs…. So, I’ve got this CD that I’ve made and is up for sale at lulu.com traditional hymns done as “chimes”. I’ve spent quite a bit of time recording to hard drive, editing and getting the wav files as good as possible and I’ve uploaded them, but I also want to make the individual songs available as mp3 downloads too. AND I want to give a preview, either a low quality mp3 of the whole, or a high quality 30 second clip…. Hmmm… how to do it.
First of lame is the tool for the wav -> mp3 conversion…. My “scripts” look like this….
mp3_high
#!/bin/bash
lame $1.wav $1_256.mp3 -b 256 -h
mp3_low
#!/bin/bash
lame $1.wav $1_32.mp3 -b 32
Ok…. but cutting them short, needs another tool mp3splt (no I didn’t mis-spell that…) a simple urpmi mp3splt solves the install….
Now, my next script looks like this….
mp3_truncate
#!/bin/bash
mp3splt $1 0.00 0.30
That essentially will make an mp3 using the first 30 seconds of the filename passed to it. But… I wanted something to glue them all together….
mp3_generate
#!/bin/bash
/home/user/scripts/mp3_high $1
/home/user/scripts/mp3_low $1
/home/user/scripts/mp3_truncate $1_256.mp3
OK…. but now, I’ve got a whole directory of wav files…. hmmm
ls *wav gives the full filename, I’ll have to get rid of the wav, or my mp3’s will be named something.wav.mp3..
mp3_batch
#!/bin/bash
for i in `ls *wav | sed ‘s/.wav//’`
do
`/home/user/scripts/mp3_generate $i`
done
and just call it from the directory that you have your wav files in.
Now, I know, I could probably spend the next three days looking for a GUI based program that can do batch operations, the gui for mp3splt might, but…. now I don’t have to look. That’s been the easiest part of the whole process.