Script to automate adding a woooop sound to videos.

add_sound_to_timelapse.sh

#!/usr/bin/env bash -e
#
# Copyright 2022 John Daniels <john@theelectricengine.com>
#
# Usage of the works is permitted provided that this instrument is retained
# with the works, so that any entity that uses the works is notified of this
# instrument.
# DISCLAIMER: THE WORKS ARE WITHOUT WARRANTY.

# This script is intended to add a woooooooop sound to short vidoes.
# Why? I automate timelapses from my 3d printer and wanted to have some sound.

function usage {
	echo "Usage:"
	echo "$0 <path to source MP4 file> <path to output MP4 file>"
}

# Check params

ORIGINAL_FILE="$1"

if [ ! -f "$ORIGINAL_FILE" ]; then
	echo "$ORIGINAL_FILE not found!"
	usage
	exit 1
fi

OUTPUT_FILE="$2"

if [ -z "$2" ]
then
	echo "Missing Output File!"
	usage
	exit 1
fi

# Check dependencies are available

if ! command -v ffmpeg &> /dev/null
then
	echo "ffmpeg is not available, please ensure it's installed!"
	exit 2
fi

if ! command -v sox &> /dev/null
then
	echo "sox is not available, please ensure it's installed!"
	exit 2
fi

DURATION=`ffmpeg -i "$ORIGINAL_FILE" 2>&1 | grep "Duration" | cut -d ' ' -f 4 | sed s/,//`
AUDIO_FILE="`mktemp`.wav"

sox -V -r 44100 -n -b 16 -c 2 $AUDIO_FILE synth $DURATION sin 100+800 vol -20dB

ffmpeg -i "$ORIGINAL_FILE" -i $AUDIO_FILE -ab 192k "$OUTPUT_FILE"