use List::Util "sum";
sub ip2rgb {
    my @ip = shift =~ /(\d+)/g;
    my $r = eval "@{[ join '^', @ip ]}";
    my $g = sum(@ip) % 255; # left-overs
    my ( $b ) = sort @ip;   # lowest of group
    print "$r, $g, $b";
}
# ip2rgb '220.17.120.164' --> 17, 11, 120
# ip2rgb '127.0.0.1' --> 126, 128, 0