if ! gifsicle -O2 -b "$1"; then

in="$1"
tmp="compress.sh-tmp-"$$".png"
fin="_$1"

rm -f "$fin"

#sizes="32 64 128 256 512 1024 2048 4096 8192 16384 32768"
#sizes="2048 4096 8192 16384 32768 65536 131072"
#sizes="16384 32768 65536 131072 $[256*1024] $[512*1024] $[1024*1024]"

sizes="-n1 -n2 -n3 -n4 -n5 -n6 -n7 -n8 -n9 -n10 -n11 -n12 -n13"
#sizes="-b-32 -b-64 -b-128 -b-256 -b-512 -b-1024 -b-2048 -b-4096 -b-8192"
#sizes="-n4 -n5 -n6 -n7"

filters="0 1 2 3 4 5"
#filters="0"
#filters="1 3 4 5"
#filters="5"

advpng -z -4 "$in"
optipng -o7 "$in" && advpng -z -4 "$in"
#wine /usr/local/bin/DeflOpt.exe "$in"
advdef -z -4 "$in" && DeflOpt "$in"

for filter in $filters;do
  for bufsize in $sizes;do
    rm -f "$tmp"
    while [ $(jobs -p|wc -l) -ge 4 ]; do sleep 0.2; done
    if true; then
      f="$tmp"."$BASHPID".png
      pngout -v -f$filter $bufsize "$in" "$f"
      advdef -z -4 "$f" && DeflOpt "$f"
      flock -x 333
      bsize="`stat -c %s $in`"
      size="`stat -c %s "$f"`"
      if [ $bsize -gt $size ]; then
        #wine /usr/local/bin/DeflOpt.exe "$f"
        mv -f "$f" "$fin"
      else
        rm -f "$f"
      fi
    fi &
  done
done 333< "$in"
wait
mv -f "$fin" "$in"

fi