Sounds like color_contrast_hex from Color::Calc would be suited 
use Color::Calc;

my $colour = 'green';
my @rgb    = color_contrast_hex($colour) =~ /(..)/g;

print "contrasted RGB = @rgb\n";

__output__

contrasted RGB = ff 00 ff

[download]

HTH

_________
broquaint

In reply to Re: Contrasting Colours by broquaint
in thread Contrasting Colours by msemtd

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