Batch audio files processing

Here I store some pretty useful commands when performing audio analysis and refinement on a larger sample of files. The SOX tool can be downloaded here.

Resample multiple files

for /r %i in (*.wav) do sox "%~ni.wav" "16khz\%~ni.wav" rate 16k

Change the bit resolution of multiple files

for %i in (*.wav) do sox "%~ni.wav" -b 16 "16bit\%~ni.wav"

Normalize multiple audio files

Specify only the maximum aplitude (here -1.0 dB) bellow the clipping level (0.0 dB). The results are stored in a folder normalized on the same level as original.

for /r %i in (*.wav) do sox "%~ni.wav" "..\normalized\%~ni_norm.wav" norm -1.0

Extract audio from a video file

The best tool for that is ffmpeg, another command line interface. Ffmpeg can be downloaded here.

ffmpeg -i video_file.mp4 audio_file.wav

Ffmpeg offers a much wider range of utilities for working with video/audio files.

Rename multiple files in the folder at once

The script asks for a root word and then renames all *.wav files in the current folder to root_1, root_2, root_3…

@echo off
:: Rename all the files in the folder with the given extension to root_x where x 
:: is the file order
:: Vojtech Illner, November 2021
TITLE Rename mutliple files

:: Enable delayed extension for loop index tracking
setlocal enableextensions enabledelayedexpansion

set /p root="Enter the root word: "
ECHO renaming files...

set /a k=0
for %%i in (*.wav) do (
    ren "%%~i" "%root%_!k!%%~xi" 
    set /a k += 1
)
endlocal
ECHO completed.