sub ip2rgb {
    my $ip = shift;
    my $bright = shift;
    my @octets = split /\./, $ip;
    my $mso = shift @octets;
    my @rgb = map { $_ >> 1 } @octets;
    my $msb = ($mso >> 6 & 0x03) ^ ($mso >> 4 & 0x03) ^ ($mso >> 2 & 0x03) ^ ($mso >> 2 & 0x03) ^ ($mso & 0x03);
    if ($msb != 3) {
        $rgb[$msb] |= 0x80;
    }
    if ($bright) {
        for (@rgb) {
            $_ ^= 0x80;
        }
    }
    return @rgb;
}