misc/tools/generate-jpeg.sh

   1 #!/bin/sh
   2
   3 set -e
   4
   5 : ${qual:=95}
   6 : ${qual_alpha:=99}
   7
   8 for X in "$@"; do
   9         case "$X" in
  10                 *.jpg)
  11                         jpegoptim --strip-all -m$qual "$X"
  12                         ;;
  13                 *.png|*.tga)
  14                         if convert "$X" -depth 16 RGBA:- | perl -e 'while(read STDIN, $_, 8) { substr($_, 6, 2) eq "\xFF\xFF" or exit 1; ++$pix; } exit not $pix;'; then
  15                                 echo "$X has no alpha, converting"
  16                                 convert "$X" -quality 100 "${X%.*}.jpg"
  17                                 jpegoptim --strip-all -m$qual "${X%.*}.jpg"
  18                                 rm -f "$X"
  19                         else
  20                                 echo "$X has alpha, converting twice"
  21                                 convert "$X" -alpha extract -quality 100 "${X%.*}.jpg"
  22                                 convert "$X" -alpha off     -quality 100 "${X%.*}_alpha.jpg"
  23                                 jpegoptim --strip-all -m$qual "${X%.*}.jpg"
  24                                 jpegoptim --strip-all -m$qual_alpha "${X%.*}_alpha.jpg"
  25                                 rm -f "$X"
  26                         fi
  27                         ;;
  28         esac
  29 done