SoX

This is the easiest software to concatenate and/or split audio files.

Download

https://sourceforge.net/projects/sox/

Wordt standaard geïsntalleerd in C:\Program Files (x86)\sox-14-4-2>

Manuals & resources

General

• http://sox.sourceforge.net/sox.html
• http://sox.wikia.com/wiki/OPTIONS (e.g. verbosity: -V0 => -V3)

Focusing on split on silence

• https://digitalcardboard.com/blog/2009/08/25/the-sox-of-silence/
• https://stackoverflow.com/questions/20014064/how-to-batch-split-audio-files-wherever-there-is-silence
• https://unix.stackexchange.com/questions/318164/sox-split-audio-on-silence-but-keep-silence

Concatenate in real life

It works with .wav, .mp3, …

Het laatste bestand is altijd het doelbestand, de voorgaande de bronbestanden:

sox first.mp3 second.mp3 third.mp3 result.mp3

see: https://stackoverflow.com/questions/25280958/sox-concatenate-multiple-audio-files-without-a-gap-in-between

C:\Program Files (x86)\sox-14-4-2>sox 1.wav 2.wav 3.wav 123.wav

Simple split in real life

De output-bestanden krijgen vanzelf een volgnummer mee:

sox infile.wav output.wav trim 0 30 : newfile : restart

Zo bijvoorbeeld:

sox 15.wav output.wav trim 0 75 : newfile : restart
sox WARN trim: Last 1 position(s) not reached (audio shorter than expected).

Je krijgt dus netjes een melding dat de laatste in de rij korter zal zijn.

Get the last part of an audio file, skipping x seconds

skip e.g. 70 seconds

sox 10.wav out.wav trim 70

Split manually in unequal sections

The following is an example of splitting (the first x seconds of) an input file into a 42.65 second file a 43.1 second file, a 73 second file and ignoring the rest. (http://sox.sourceforge.net/sox.html)

sox BuxIn034.wav BuxOut%1n.wav trim 0 42.65 : newfile : trim 0 43.1 : newfile : trim 0 73

Split where silence

See another example splitwavxx.bat.

I had a large .wav file from a concert, that I wanted to split into the separate pieces, based on the silence between the pieces. I knew there were 43 pieces, an intro and an applause at the end, so in total I needed 45 files:

sox -V3 BuxIn.wav BuxOut.wav silence 1 3.0 0.1% 1 0.3 1% : newfile : restart

→ 100 files / 17

https://unix.stackexchange.com/questions/318164/sox-split-audio-on-silence-but-keep-silence

• The first triplet of values means remove silence, if any, at the start until 3.0 seconds of sound above 0.1%.
• The second triplet means stop when there is at least 0.3 seconds of silence below 1%. changed into: 0.3 seconds of silence below 0.3%

sox -V3 BuxIn.wav BuxOut.wav silence 1 3.0 0.1% 1 0.3 0.3% : newfile : restart

→ 33 files => changed into: 0.3 seconds of silence below 0.38% / 7-1 = 6

sox -V3 BuxIn.wav BuxOut.wav silence 1 3.0 0.1% 1 0.3 0.38% : newfile : restart

→ 46 files => OK / 7-1 = 6

Other trials, from commands I found on the www:

sox BuxIn.wav BuxOut.wav silence 1 0.5 1% 1 5.0 1% : newfile : restart

→ 10 files

sox BuxIn.wav BuxOut.wav silence -l 1 0.0 -40d 1 1.0 -40d : newfile : restart

→ 125 files / 14-2 = 12 (verwacht 6, maar al bij al niet slecht)

Split where silence 2

sox soundIn.mp3 soundOut.mp3 silence 1 2 0.5% 1 2.7 1% : newfile : restart

• verwacht: 19
• resultaat: 18, waarvan 4 van 0 kB, dus 14
• = al bij al niet slecht

► 18 - 4 = 14

Op basis hiervan telkens één parameter gewijzigd:

sox sound1.mp3 soundOut1.mp3 silence 0.5 2 0.5% 1 2.7 1% : newfile : restart

sox FAIL silence: usage: [ -l ] above_periods [ duration threshold[d|%] ] [ below_periods duration threshold[d|%] ]

sox sound2.mp3 soundOut2.mp3 silence 1 2.5 0.5% 1 2.7 1% : newfile : restart

► 14 - 1 = 13

sox sound3.mp3 soundOut3.mp3 silence 1 2 0.3% 1 2.7 1% : newfile : restart

► 21 - 8 = 13

sox sound4.mp3 soundOut4.mp3 silence 1 2 0.5% 0.5 2.7 1% : newfile : restart

► 18 - 5 = 13

sox sound5.mp3 soundOut5.mp3 silence 1 2 0.5% 1 1.5 1% : newfile : restart

► 35 - 8 = 27

sox sound6.mp3 soundOut6.mp3 silence 1 2 0.5% 1 2.7 0.7% : newfile : restart

► 14 - 1 = 13

No SoX

Sometimes, I also use NCH Slice Audio File Splitter (https://www.nch.com.au/splitter/index.html).