split wav file into parts of equal duration, padding with silence if needed

Question

I need to split wav files into multiple 10-second-long wav files, but each resulting wav file must be exactly 10 seconds in length, adding silence if needed – so if a wav file's duration in seconds isn't a multiple of 10, the last wav file should be padded with silence.

I've seen some answers (1, 2, 3) which show how to use sox and ffmpeg to split a file into chunks of equal length:

$ ffmpeg -i file.wav -f segment -segment_time 10 -c copy out%03d.wav

$ sox file.wav output-.wav trim 0 10 : newfile : restart

but the last file produced by these commands is usually less than 10 seconds long. Is there a way to split a wav file, padding the last file if needed, in the same command?

score 2 · Accepted Answer · answered Jan 28 '21 at 16:30

Split the files, inspect the resulting files (for i in *wav), if (length < 10 seconds), pad them.

To get the wave file length: sox --info -D file.wav
To pad the wave file: https://superuser.com/questions/579008/add-1-second-of-silence-to-audio-through-ffmpeg

Maybe do some calculations :-)

split wav file into parts of equal duration, padding with silence if needed

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