I personally believe that there are tons of better, more reliable, and format-specific extractors of images for "container" files like pdf, or (those damned) pps, etc.: either free (for one of the two acceptations of the word) or not. But yesterday I was in a quick need of extracting the jpeg images contained in one such file, so I quickly checked JPEG @ Wikipedia for the headers's markers and I concocted up the latter, possibly complete of some minimal YAGNI (I know I shouldn't) for future development: it worked for me!

#!/usr/bin/perl

use strict;
use warnings;
use 5.010;

use open IO => ':raw';

use File::Basename;
my $progname;
BEGIN { ($progname) = fileparse $0, qr/\.pl/i; }

local $/;

my %cnt;
while (<>) {
    while ( /(\xFF\xD8 .*? \xFF\xD9)/xsg ) {
        for my $name ($ARGV . ++$cnt{$ARGV} . '.jpeg') {
            open my $fh, '>', $name or die "Can't open `$name': $!\n";
            warn "[$progname] Creating `$name'\n";
            print $fh $1;
        }
    }
}

__END__
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