rgeraldporter/spectrogram.sh

## spectrogram.sh
#!/usr/bin/env bash

# Note that some tweaks may be required to make the overlay "line" to appear correctly where the audio is actually playing
# The overlay.png needs to be 1920 x 784 for this, if you change scale you'll need to change that file size
# FFMPEG makes very stuttery videos in spectrograms in some ratios/resolutions; I've tried to do high res but with little success
# So far these settings are the smoothest I can get, but it can still look a bit stuttery in YouTube / full screen on a big screen

# The various steps below involve generating the spectrogram, adding the overlay visual, adding the audio,
#  moving the audio over a bit to line up with the play line, framing the video in a more standard resolution/ratio

# On MacOS I ran this using: (where mp3 is name-of-file.mp3)
# sh spectrogram.sh name-of-file

if [ "$1" != "" ]; then
    echo "Converting to spectrogram video..."
else
    echo "You must provide an MP3 file name."
fi

ffmpeg -i "$1.mp3" \
-filter_complex "aevalsrc=0|0:d=18[silence];[0:a][silence]concat=n=2:v=0:a=1[out]" \
-map [out] -c:a libmp3lame -q:a 2 stage-0.mp3 -y && \
ffmpeg -i stage-0.mp3 -filter_complex \
"[0:a]showspectrum=s=1250x500:fps=60:mode=combined:color=intensity:stop=12000:slide=scroll,format=yuv420p[v]" \
 -map "[v]" -map 0:a \
 -b:v 700k -b:a 360k stage-1.mp4 -y && \
ffmpeg -i stage-1.mp4 -vf scale=1920x784 stage-2.mp4 -y && \
ffmpeg -i stage-2.mp4 -i overlay.png -filter_complex "overlay=0:0" stage-3.mp4 -y && \
ffmpeg -i stage-3.mp4 -ss 12 -vcodec copy -acodec copy stage-4.mp4 -y && \
ffmpeg -i stage-4.mp4 -i "$1.mp3" -c:v copy -map 0:v:0 -map 1:a:0 stage-5.mp4 -y && \
ffmpeg -i stage-5.mp4 -itsoffset 3.1 -i stage-5.mp4 -strict -2 -map 0:v -map 1:a -c copy "$1.mp4" -y

# remove this to clean up after itself; can leave it in case things don't work right and you can figure out at what stage things went wrong
#rm -rf stage-*.mp4
	#!/usr/bin/env bash

	# Note that some tweaks may be required to make the overlay "line" to appear correctly where the audio is actually playing
	# The overlay.png needs to be 1920 x 784 for this, if you change scale you'll need to change that file size
	# FFMPEG makes very stuttery videos in spectrograms in some ratios/resolutions; I've tried to do high res but with little success
	# So far these settings are the smoothest I can get, but it can still look a bit stuttery in YouTube / full screen on a big screen

	# The various steps below involve generating the spectrogram, adding the overlay visual, adding the audio,
	# moving the audio over a bit to line up with the play line, framing the video in a more standard resolution/ratio

	# On MacOS I ran this using: (where mp3 is name-of-file.mp3)
	# sh spectrogram.sh name-of-file

	if [ "$1" != "" ]; then
	echo "Converting to spectrogram video..."
	else
	echo "You must provide an MP3 file name."
	fi

	ffmpeg -i "$1.mp3" \
	-filter_complex "aevalsrc=0\|0:d=18[silence];[0:a][silence]concat=n=2:v=0:a=1[out]" \
	-map [out] -c:a libmp3lame -q:a 2 stage-0.mp3 -y && \
	ffmpeg -i stage-0.mp3 -filter_complex \
	"[0:a]showspectrum=s=1250x500:fps=60:mode=combined:color=intensity:stop=12000:slide=scroll,format=yuv420p[v]" \
	-map "[v]" -map 0:a \
	-b:v 700k -b:a 360k stage-1.mp4 -y && \
	ffmpeg -i stage-1.mp4 -vf scale=1920x784 stage-2.mp4 -y && \
	ffmpeg -i stage-2.mp4 -i overlay.png -filter_complex "overlay=0:0" stage-3.mp4 -y && \
	ffmpeg -i stage-3.mp4 -ss 12 -vcodec copy -acodec copy stage-4.mp4 -y && \
	ffmpeg -i stage-4.mp4 -i "$1.mp3" -c:v copy -map 0:v:0 -map 1:a:0 stage-5.mp4 -y && \
	ffmpeg -i stage-5.mp4 -itsoffset 3.1 -i stage-5.mp4 -strict -2 -map 0:v -map 1:a -c copy "$1.mp4" -y

	# remove this to clean up after itself; can leave it in case things don't work right and you can figure out at what stage things went wrong
	#rm -rf stage-*.mp4