png-verify.pl

   1 #!/usr/bin/perl
   2
   3 use strict;
   4 use warnings;
   5
   6 my $infile = shift ||
   7     die "no input file specified\n";
   8
   9 my $dpcm = 58; # expected
  10
  11 my $tmp = `identify -units PixelsPerCentimeter -format '%x x %y' $infile`;
  12
  13 die "got unexpected density '$tmp' (fix with png-cleanup.pl)\n"
  14     if $tmp ne "$dpcm x $dpcm";
  15
  16 exit 0;