How to create jar file from command line?

Simple command line audio file concatenation task?

• I have many folders each of which contains 125 or so brief wav files (1 - 4 seconds) with file names 001.wav, 002.wav ... n.wav. I want to create a long wav file for each folder that has the original files intercut with periods of silence equal to x times the length of the preceding individual source wav file. So, like, 001.wav + silence of length x times the length of 001.wav + 002.wav + silence of length x times the length of 002.wav + and so on. Can this be done elegantly with a command line utility such as sox without getting into shell scripting, about which I am ignorant? http://sox.sourceforge.net/sox.html seems to be able to generate wav files of silence of whatever duration desired, and its sub-utility soxi can get the length of a wav file, but I'm having trouble seeing how to combine the two to spit out what I want. If it cannot be done without shell scripting, any hints as to what the script would look like? Or are there other utilities I should consider?

• Answer:

  Because you want to do math on the duration and such, I think you need a script. This ought to do it if zsh is available:#!/usr/bin/env zshBITRATE=44100X=3for f in *.wav; do length=$(( $X * $(soxi -D $f) )) sf=${f%%.*}s.wav sox -n -r $BITRATE $sf trim 0.0 $lengthdonesox *.wav out.wavI used zsh because you need to do floating point math on the duration and floating point in bash requires using awk or bc which is kind of a pain.