I ran your example and encountered the same problem. I finally had to break it up a little and did this:

#!/usr/bin/perl 

use strict;
use warnings;
use Imager qw(:all);
use Imager::Color;
use Imager::Color::Table;
use Data::Dump qw(dump);
use Term::ANSIColor::Print;

my $print = Term::ANSIColor::Print->new();

$print->black("=" x 15);
$print->dark_green("Color Table: ");
$print->black("=" x 15);

my @rgb = Imager::Color::Table->get('red');
$print->dark_red("red   is ", @rgb);
@rgb = Imager::Color::Table->get('green');
$print->dark_green("green is ", @rgb);
@rgb = Imager::Color::Table->get('blue');
$print->dark_blue("blue  is ", @rgb);
$print->black("=" x 43);

my $c1 = Imager::Color->new(255, 0, 0);
my $c2 = Imager::Color->new(0, 255, 0);
my $c3 = Imager::Color->new(0, 0, 255);
my $c4 = Imager::Color->new( xsize => 5, ysize => 15, );

$print->dark_red("The first  channel hsv is: ", 
    dump my @hsv1 = $c1->hsv());
$print->dark_green("The second channel hsv is: ", 
    dump my @hsv2 = $c2->hsv());
$print->dark_blue("The third  channel hsv is: ", 
    dump my @hsv3 = $c3->hsv());
$print->black("=" x 43);
    
$print->dark_magenta("The rgba is: ");
$print->dark_red("r: ", 
    dump $c1->rgba());
$print->dark_green("g: ", 
    dump $c2->rgba());
$print->dark_blue("b: ",
    dump$c3->rgba());
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