misc/tools/jpeg-if-not-alpha.sh

   1 #!/bin/sh
   2
   3 set -e
   4
   5 : ${qual:=95}
   6
   7 for X in "$@"; do
   8         case "$X" in
   9                 *.jpg)
  10                         if [ -n "$scaledown" ]; then
  11                                 mogrify -geometry "$scaledown>" -quality 100 "$X"
  12                         fi
  13                         jpegoptim --strip-all -m$qual "$X"
  14                         ;;
  15                 *.png|*.tga)
  16                         if [ -n "$scaledown" ]; then
  17                                 mogrify -geometry "$scaledown>" -quality 100 "$X"
  18                         fi
  19                         if convert "$X" -depth 16 RGBA:- | perl -e 'while(read STDIN, $_, 8) { substr($_, 6, 2) eq "\xFF\xFF" or exit 1; ++$pix; } exit not $pix;'; then
  20                                 echo "$X has no alpha, converting"
  21                                 convert "$X" -quality 100 "${X%.*}.jpg"
  22                                 jpegoptim --strip-all -m$qual "${X%.*}.jpg"
  23                                 rm -f "$X"
  24                         else
  25                                 echo "$X has alpha, not converting"
  26                         fi
  27                         ;;
  28         esac
  29 done