webp_to_gif.sh

for FILENAME_WEBP in `ls $1 | grep "webp"`
do

  DELAY=${DELAY:-10}
  LOOP=${LOOP:-0}
  echo $FILENAME_WEBP
  FILENAME_WEBP_PREFIX=$(echo $FILENAME_WEBP | sed 's/\(.*\)\.webp/\1/')
  echo $FILENAME_WEBP_PREFIX
  n=`webpinfo -summary $FILENAME_WEBP | grep frames | sed -e 's/.* \([0-9]*\)$/\1/'`
  dur=`webpinfo -summary $FILENAME_WEBP | grep Duration | head -1 |  sed -e 's/.* \([0-9]*\)$/\1/'`

  if (( $dur > 0 )); then
      DELAY = dur
  fi
  for i in $(seq -f "%05g" 1 $n)
  do
      webpmux -get frame $i $FILENAME_WEBP -o $FILENAME_WEBP_PREFIX.$i.webp
      dwebp $FILENAME_WEBP_PREFIX.$i.webp -o $FILENAME_WEBP_PREFIX.$i.png
  done

  convert $FILENAME_WEBP_PREFIX.*.png -delay $DELAY -loop $LOOP $FILENAME_WEBP_PREFIX.gif
  rm $FILENAME_WEBP_PREFIX.[0-9]*.png $FILENAME_WEBP_PREFIX.[0-9]*.webp
done