tocqt.sh

#!/bin/sh

CTR=0
while [ -f "out$CTR.mkv" ]; do
  let CTR=CTR+1
done

if [ -z "$1" ]; then
  echo "missing input argument"
  exit 1
fi

ffmpeg -f lavfi -i 'amovie='"$1"', asplit [a][out1]; [a] showcqt=fps=30:count=5 [out0]' \
  -vf scale=3840:2160 \
  -c:v libx264 -crf 24 -preset ultrafast \
          -profile:v high -pix_fmt yuv420p \
  -c:a copy \
  out$CTR.mkv