Rename digital photo files according to EXIF date information

Please note that while I provide this script in the hopes that it will be useful to you, I make NO GUARANTEES OR WARRANTIES OF ANY KIND. The code is provided subject to the same terms as Perl itself. For more information, please refer to the Perl Artistic License.

#!/usr/bin/perl

# Image files will renamed to YYYY_MMDD_HHMMSSxx where xx is
# a two letter suffix to distinguish images that were taken within
# the same second

use strict; use warnings;

use File::Slurp;
use Image::ExifTool 'ImageInfo';

my @files = grep { /.jpe?g\z/i } read_dir;

rename_to_exif_date($_) for (@files);

sub rename_to_exif_date {
   my ($img) = @_;

   my $ts = ImageInfo($img, 'DateTimeOriginal')->{DateTimeOriginal};
   return unless defined $ts;
   my $d4 = '([0-9]{4})';
   my $d2 = '([0-9]{2})';

   if( my ($year, $mon, $day, $hr, $min, $sec) = (
           $ts =~ /^$d4 : $d2 : $d2 \s $d2 : $d2 : $d2 \z/ ) ) {
      my $new_name = "${year}_$mon${day}_$hr$min$sec";
      my $suffix = 'aa';
      ++$suffix while -e "$new_name$suffix.jpg";
      $new_name .= "$suffix.jpg";
      return rename $img, $new_name;
   }
   return;
}__END__