You're working too hard at it. Relax a little, and it'll work. I reworked your script, and it works with no errors. I really couldn't see any reason to use errstr, so I eliminated it. 
#!/usr/bin/perl

use strict;
use warnings;
use CAM::PDF;

convert_pdf_to_text();

sub convert_pdf_to_text {
    use CAM::PDF::PageText;
    my $pdf_filename = '/path/to/pdf';
    my $pdf = CAM::PDF->new($pdf_filename);
    my $y   = $pdf->getPageContentTree(1);
    print CAM::PDF::PageText->render($y);
}

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In reply to Re: Converting Text from PDF using CAM::PDF by Khen1950fx
in thread Converting Text from PDF using CAM::PDF by mr_p

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