perl - Errors reading PDF with CAM-PDF: use of uninitialized value in addition <+> line 667 -

i'm new perl , i'm trying read pdf file using cam::pdf here code:

when try run in command prompt these errors:

"use of uninitialized value in addition <+> @ c:/strawberry/perl/site/lib/cam/pdf.pm line 667 ... substr outside of str @ c:/strawberry/perl/site/lib/cam/pdf.pm line 657 ... (at end)... "bad request object 60 @ position 0 in file can't call method "getpagecontenttree" on undefined value @ c:...

the weird thing have exact same files , program on separate computer runs fine. prints computer can't.

i've tried reinstalling cam::pdf , reinstalling cpan. reinstall failed reason too. help.

#!/usr/bin/perl  use strict; use warnings;  use cam::pdf; use cam::pdf::pagetext;  #in cmd: courts.pl samplepdf.pdf  $filename = shift || die "supply pdf on command line\n";  $pdf = cam::pdf->new($filename);   #print text_from_page(1);  $string = text_from_page(1); #print $string;  $string =~ s/\b \b//g; print $string;  open(my $fh, '>', 'reports.txt'); print $fh "$string"; close $fh; print "done\n";  sub text_from_page { $pg_num = shift;  return cam::pdf::pagetext->render($pdf->getpagecontenttree($pg_num)); }