Question

I have a web application that let’s people make sound effects. Sometimes the sound effects are less than 0.55 seconds in length. When this is the case they may fail to play properly in the Chrome browser. I would like to know of a command line audio processing utility that will enable me to pad out the sounds shorter than 0.55s with emptiness to increase the sound duration to be at least 0.55s.

I have looked into Audacity batch processing, but could not figure out how to use it on the command line. I have also looked into using sox, but could not find an option for extending a sound to be a minimum duration.

Answer 1

Use

sox -n silence.wav trim 0.55

to generate a 0.55s long file of silence.

Then

sox -m -v 1 yourfile.wav silence.wav -t wav outfile