Skip site navigation (1)Skip section navigation (2)

FreeBSD Manual Pages


home | help
Convert::Color::HSV(3)User Contributed Perl DocumentatioConvert::Color::HSV(3)

       "Convert::Color::HSV" - a color value represented as


	use Convert::Color::HSV;

	my $red	= Convert::Color::HSV->new( 0, 1, 1 );

	# Can also parse strings
	my $pink = Convert::Color::HSV->new( '0,0.7,1' );

       Via Convert::Color:

	use Convert::Color;

	my $cyan = Convert::Color->new(	'hsv:300,1,1' );

       Objects in this class represent a color in HSV space, as	a set of three
       floating-point values. Hue is stored as a value in degrees, in the
       range 0 to 360 (exclusive). Saturation and value	are in the range 0 to

       This color space	may be considered as a cylinder, of height and radius
       1. Hue represents the position of the color as the angle	around the
       axis, the saturation the	distance from the axis,	and the	value the
       height above the	base. In this shape, the entire	base of	the cylinder
       is pure black, the axis through the centre represents the range of
       greys, and the circumference of the top of the cylinder contains	the
       pure-saturated color wheel, with	a pure white point at its centre.

       Because the entire bottom surface of this cylinder contains black, a
       closely-related color space can be created by reshaping the cylinder
       into a cone by contracting the base of the cylinder into	a point. The
       radius from the axis is called the chroma (though this is a different
       definition of "chroma" than that	used by	CIE).

   $color = Convert::Color::HSV->new( $hue, $saturation, $value	)
       Returns a new object to represent the set of values given. The hue
       should be in the	range 0	to 360 (exclusive), and	saturation and value
       should be between 0 and 1. Values outside of these ranges will be

   $color = Convert::Color::HSV->new( $string )
       Parses $string for values, and construct	a new object similar to	the
       above three-argument form. The string should be in the form


       containing the three floating-point values in decimal notation.

   $h =	$color->hue
   $s =	$color->saturation
   $v =	$color->value
       Accessors for the three components of the color.

   $c =	$color->chroma
       Returns the derived property of "chroma", which maps the	color space
       onto a cone instead of a	cylinder. This more closely measures the
       intuitive concept of how	"colorful" the color is	than the saturation
       value and is useful for distance	calculations.

   ( $hue, $saturation,	$value ) = $color->hsv
       Returns the individual hue, saturation and value	components of the
       color value.

   $measure = $color->dst_hsv( $other )
       Returns a measure of the	distance between the two colors. This is the
       Euclidean distance between the two colors as points in the chroma-
       adjusted	cone space.

   $measure = $color->dst_hsv_cheap( $other )
       Returns a measure of the	distance between the two colors. This is used
       in the calculation of "dst_hsv" but since it omits the final square-
       root and	scaling	it is cheaper to calculate, for	use in cases where
       only the	relative values	matter,	such as	when picking the "best match"
       out of a	set of colors. It ranges between 0 for identical colors	and 4
       for the distance	between	complementary pure-saturated colors.

       o   Convert::Color - color space	conversions

       o   Convert::Color::RGB - a color value represented as red/green/blue

       o   <> -	HSL and	HSV on

       Paul Evans <>

perl v5.32.1			  2014-06-01		Convert::Color::HSV(3)


Want to link to this manual page? Use this URL:

home | help