use Data::Dumper;

my %t;
for my $i (0..63) {
    for my $j (0..63) {
        $t{sprintf "%03x", $i*64 + $j} = [$i, $j];
    }
}

my $buf;
my @bytes;
while (read STDIN, $buf, 4096) {
    my $hex = unpack "H*" => $buf;
    while ($hex =~ /(...)/g) {
        push @bytes, @{$t{$1}};
    }
}

print Dumper \@bytes;