length="${length#*duration=}" length="${length%%${BR}*}" length="${length%.*}"
# ffmpeg -nostdin -y -i "$file" -vf fps=11/$length,scale=320:-2 -frames 10 "$tmp/thumb_%02d.jpg" 2>&-
length="${length#*duration=}" length="${length%%${BR}*}" length="${length%.*}"
# ffmpeg -nostdin -y -i "$file" -vf fps=11/$length,scale=320:-2 -frames 10 "$tmp/thumb_%02d.jpg" 2>&-