Maybe this will help to someone: we came to this solution simulating UInt: 
#!/usr/bin/perl
use strict;
use warnings;

print OpenSubtitlesHash('breakdance.avi');

sub OpenSubtitlesHash {
    my $filename = shift or die("Need video filename");

    open my $handle, "<", $filename or die $!;
    my $fsize = -s $filename;

    my $hash = [$fsize & 0xFFFF, ($fsize >> 16) & 0xFFFF, 0, 0];

    $hash = AddUINT64($hash, ReadUINT64($handle)) for (1..8192);

    my $offset = $fsize - 65536;
    seek($handle, $offset > 0 ? $offset : 0, 0) or die $!;

    $hash = AddUINT64($hash, ReadUINT64($handle)) for (1..8192);

    close $handle or die $!;
    return UINT64FormatHex($hash);
}

sub ReadUINT64 {
    read($_[0], my $u, 8);
       return [unpack("vvvv", $u)];
}

sub AddUINT64 {
    my $o = [0,0,0,0];
    my $carry = 0;
    for my $i (0..3) {
        if (($_[0]->[$i] + $_[1]->[$i] + $carry) > 0xffff ) {
            $o->[$i] += ($_[0]->[$i] + $_[1]->[$i] + $carry) & 0xffff;
            $carry = 1;
        } else {
            $o->[$i] += ($_[0]->[$i] + $_[1]->[$i] + $carry);
            $carry = 0;
        }
    }
    return $o;
}

sub UINT64FormatHex {
    return sprintf("%04x%04x%04x%04x", $_[0]->[3], $_[0]->[2], $_[0]->
+[1], $_[0]->[0]);
}

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In reply to Re: Creating custom hash of file by 2ge
in thread Creating custom hash of file by 2ge

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