#!/bin/bash
for file in *.mkv
do
filename="${file%%.*}"
ffmpeg -y -i "$file" -map 0:s:0 subtitles.ass
ffmpeg -y -i "$file" -vf subtitles=subtitles.ass -map 0:v:0 -map 0:a:0 -c:v libvpx-vp9 -b:v 499k -c:a libopus -b:a 128k -speed 5 "$filename.webm"
done