Convert all ani files to each gif files (depended imagemagick & ani2ico https://gist.github.com/RkEclair/cc78aab9bba641928fbb577939ef5a9d)

ani2gif.sh

#!/bin/sh
set -u
PATH='/usr/bin:/bin:/usr/local/bin'
IFS=' 	
'

for f in *.ani; do
	echo "Processing $f..."
	ani2ico $f
	icos=$(ls -v $f?.ico)
	ls $icos # please comment it out if annoying
	convert -dispose background -loop 0 -delay 20 $icos ${f%%.ani}.gif
done

rm -f *.ico