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<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd">
<refentry id="libgimpcolor-GimpColorSpace">
<refmeta>
<refentrytitle>GimpColorSpace</refentrytitle>
<manvolnum>3</manvolnum>
<refmiscinfo>LIBGIMPCOLOR Library</refmiscinfo>
</refmeta>
<refnamediv>
<refname>GimpColorSpace</refname><refpurpose>Utility functions which convert colors between different color models.</refpurpose>
</refnamediv>
<refsynopsisdiv><title>Synopsis</title>
<synopsis>
<link linkend="GimpHSL">GimpHSL</link>;
<link linkend="void">void</link> <link linkend="gimp-rgb-to-hsv">gimp_rgb_to_hsv</link> (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="GimpHSV">GimpHSV</link> *hsv);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-hsl">gimp_rgb_to_hsl</link> (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="GimpHSL">GimpHSL</link> *hsl);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-cmyk">gimp_rgb_to_cmyk</link> (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="gdouble">gdouble</link> pullout,
<link linkend="GimpCMYK">GimpCMYK</link> *cmyk);
<link linkend="void">void</link> <link linkend="gimp-hsv-to-rgb">gimp_hsv_to_rgb</link> (const <link linkend="GimpHSV">GimpHSV</link> *hsv,
<link linkend="GimpRGB">GimpRGB</link> *rgb);
<link linkend="void">void</link> <link linkend="gimp-hsl-to-rgb">gimp_hsl_to_rgb</link> (const <link linkend="GimpHSL">GimpHSL</link> *hsl,
<link linkend="GimpRGB">GimpRGB</link> *rgb);
<link linkend="void">void</link> <link linkend="gimp-cmyk-to-rgb">gimp_cmyk_to_rgb</link> (const <link linkend="GimpCMYK">GimpCMYK</link> *cmyk,
<link linkend="GimpRGB">GimpRGB</link> *rgb);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-hwb">gimp_rgb_to_hwb</link> (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="gdouble">gdouble</link> *hue,
<link linkend="gdouble">gdouble</link> *whiteness,
<link linkend="gdouble">gdouble</link> *blackness);
<link linkend="void">void</link> <link linkend="gimp-hwb-to-rgb">gimp_hwb_to_rgb</link> (<link linkend="gdouble">gdouble</link> hue,
<link linkend="gdouble">gdouble</link> whiteness,
<link linkend="gdouble">gdouble</link> blackness,
<link linkend="GimpRGB">GimpRGB</link> *rgb);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-hsv-int">gimp_rgb_to_hsv_int</link> (<link linkend="gint">gint</link> *red,
<link linkend="gint">gint</link> *green,
<link linkend="gint">gint</link> *blue);
<link linkend="void">void</link> <link linkend="gimp-hsv-to-rgb-int">gimp_hsv_to_rgb_int</link> (<link linkend="gint">gint</link> *hue,
<link linkend="gint">gint</link> *saturation,
<link linkend="gint">gint</link> *value);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-hsl-int">gimp_rgb_to_hsl_int</link> (<link linkend="gint">gint</link> *red,
<link linkend="gint">gint</link> *green,
<link linkend="gint">gint</link> *blue);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-cmyk-int">gimp_rgb_to_cmyk_int</link> (<link linkend="gint">gint</link> *red,
<link linkend="gint">gint</link> *green,
<link linkend="gint">gint</link> *blue,
<link linkend="gint">gint</link> *pullout);
<link linkend="void">void</link> <link linkend="gimp-cmyk-to-rgb-int">gimp_cmyk_to_rgb_int</link> (<link linkend="gint">gint</link> *cyan,
<link linkend="gint">gint</link> *magenta,
<link linkend="gint">gint</link> *yellow,
<link linkend="gint">gint</link> *black);
<link linkend="gint">gint</link> <link linkend="gimp-rgb-to-l-int">gimp_rgb_to_l_int</link> (<link linkend="gint">gint</link> red,
<link linkend="gint">gint</link> green,
<link linkend="gint">gint</link> blue);
<link linkend="void">void</link> <link linkend="gimp-hsl-to-rgb-int">gimp_hsl_to_rgb_int</link> (<link linkend="gint">gint</link> *hue,
<link linkend="gint">gint</link> *saturation,
<link linkend="gint">gint</link> *lightness);
<link linkend="void">void</link> <link linkend="gimp-rgb-to-hsv4">gimp_rgb_to_hsv4</link> (<link linkend="guchar">guchar</link> *rgb,
<link linkend="gdouble">gdouble</link> *hue,
<link linkend="gdouble">gdouble</link> *saturation,
<link linkend="gdouble">gdouble</link> *value);
<link linkend="void">void</link> <link linkend="gimp-hsv-to-rgb4">gimp_hsv_to_rgb4</link> (<link linkend="guchar">guchar</link> *rgb,
<link linkend="gdouble">gdouble</link> hue,
<link linkend="gdouble">gdouble</link> saturation,
<link linkend="gdouble">gdouble</link> value);
</synopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
When programming pixel data manipulation functions you will often use
algorithms operating on a color model different from the one GIMP
uses. This file provides utility functions to convert colors between
different color spaces.
</para>
</refsect1>
<refsect1>
<title>Details</title>
<refsect2>
<title><anchor id="GimpHSL"/>GimpHSL</title>
<indexterm><primary>GimpHSL</primary></indexterm><programlisting>typedef struct {
gdouble h, s, l, a;
} GimpHSL;
</programlisting>
<para>
</para></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-hsv"/>gimp_rgb_to_hsv ()</title>
<indexterm><primary>gimp_rgb_to_hsv</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_hsv (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="GimpHSV">GimpHSV</link> *hsv);</programlisting>
<para>
Does a conversion from RGB to HSV (Hue, Saturation,
Value) colorspace.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> A color value in the RGB colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>hsv</parameter> :</term>
<listitem><simpara> The value converted to the HSV colorspace
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-hsl"/>gimp_rgb_to_hsl ()</title>
<indexterm><primary>gimp_rgb_to_hsl</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_hsl (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="GimpHSL">GimpHSL</link> *hsl);</programlisting>
<para>
Convert an RGB color value to a HSL (Hue, Saturation, Lightness)
color value.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> A color value in the RGB colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>hsl</parameter> :</term>
<listitem><simpara> The value converted to HSL
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-cmyk"/>gimp_rgb_to_cmyk ()</title>
<indexterm><primary>gimp_rgb_to_cmyk</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_cmyk (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="gdouble">gdouble</link> pullout,
<link linkend="GimpCMYK">GimpCMYK</link> *cmyk);</programlisting>
<para>
Does a naive conversion from RGB to CMYK colorspace. A simple
formula that doesn't take any color-profiles into account is used.
The amount of black pullout how can be controlled via the <parameter>pullout</parameter>
parameter. A <parameter>pullout</parameter> value of 0 makes this a conversion to CMY.
A value of 1 causes the maximum amount of black to be pulled out.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> A value in the RGB colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>pullout</parameter> :</term>
<listitem><simpara> A scaling value (0-1) indicating how much black should be
pulled out
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>cmyk</parameter> :</term>
<listitem><simpara> The input value naively converted to the CMYK colorspace
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-hsv-to-rgb"/>gimp_hsv_to_rgb ()</title>
<indexterm><primary>gimp_hsv_to_rgb</primary></indexterm><programlisting><link linkend="void">void</link> gimp_hsv_to_rgb (const <link linkend="GimpHSV">GimpHSV</link> *hsv,
<link linkend="GimpRGB">GimpRGB</link> *rgb);</programlisting>
<para>
Converts a color value from HSV to RGB colorspace</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>hsv</parameter> :</term>
<listitem><simpara> A color value in the HSV colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> The returned RGB value.
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-hsl-to-rgb"/>gimp_hsl_to_rgb ()</title>
<indexterm><primary>gimp_hsl_to_rgb</primary></indexterm><programlisting><link linkend="void">void</link> gimp_hsl_to_rgb (const <link linkend="GimpHSL">GimpHSL</link> *hsl,
<link linkend="GimpRGB">GimpRGB</link> *rgb);</programlisting>
<para>
Convert a HSL color value to an RGB color value.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>hsl</parameter> :</term>
<listitem><simpara> A color value in the HSL colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> The value converted to a value in the RGB colorspace
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-cmyk-to-rgb"/>gimp_cmyk_to_rgb ()</title>
<indexterm><primary>gimp_cmyk_to_rgb</primary></indexterm><programlisting><link linkend="void">void</link> gimp_cmyk_to_rgb (const <link linkend="GimpCMYK">GimpCMYK</link> *cmyk,
<link linkend="GimpRGB">GimpRGB</link> *rgb);</programlisting>
<para>
Does a simple transformation from the CMYK colorspace to the RGB
colorspace, without taking color profiles into account.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>cmyk</parameter> :</term>
<listitem><simpara> A color value in the CMYK colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> The value converted to the RGB colorspace
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-hwb"/>gimp_rgb_to_hwb ()</title>
<indexterm><primary>gimp_rgb_to_hwb</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_hwb (const <link linkend="GimpRGB">GimpRGB</link> *rgb,
<link linkend="gdouble">gdouble</link> *hue,
<link linkend="gdouble">gdouble</link> *whiteness,
<link linkend="gdouble">gdouble</link> *blackness);</programlisting>
<para>
Theoretically, hue 0 (pure red) is identical to hue 6 in these transforms.
Pure red always maps to 6 in this implementation. Therefore UNDEFINED can
be defined as 0 in situations where only unsigned numbers are desired.
</para>
<para>
RGB are each on [0, 1]. Whiteness and Blackness are returned in the
range [0, 1] and H is returned in the range [0, 6]. If W == 1 - B, H is
undefined.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> A color value in the RGB colorspace
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>hue</parameter> :</term>
<listitem><simpara> The hue value of the above color, in the range 0 to 6
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>whiteness</parameter> :</term>
<listitem><simpara> The whiteness value of the above color, in the range 0 to 1
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>blackness</parameter> :</term>
<listitem><simpara> The blackness value of the above color, in the range 0 to 1
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-hwb-to-rgb"/>gimp_hwb_to_rgb ()</title>
<indexterm><primary>gimp_hwb_to_rgb</primary></indexterm><programlisting><link linkend="void">void</link> gimp_hwb_to_rgb (<link linkend="gdouble">gdouble</link> hue,
<link linkend="gdouble">gdouble</link> whiteness,
<link linkend="gdouble">gdouble</link> blackness,
<link linkend="GimpRGB">GimpRGB</link> *rgb);</programlisting>
<para>
H is defined in the range [0, 6] or UNDEFINED, B and W are both in the
range [0, 1]. The returned RGB values are all in the range [0, 1].</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>hue</parameter> :</term>
<listitem><simpara> A hue value, in the range 0 to 6
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>whiteness</parameter> :</term>
<listitem><simpara> A whiteness value, in the range 0 to 1
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>blackness</parameter> :</term>
<listitem><simpara> A blackness value, in the range 0 to 1
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> The above color converted to the RGB colorspace
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-hsv-int"/>gimp_rgb_to_hsv_int ()</title>
<indexterm><primary>gimp_rgb_to_hsv_int</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_hsv_int (<link linkend="gint">gint</link> *red,
<link linkend="gint">gint</link> *green,
<link linkend="gint">gint</link> *blue);</programlisting>
<para>
The arguments are pointers to int representing channel values in
the RGB colorspace, and the values pointed to are all in the range
[0, 255].
</para>
<para>
The function changes the arguments to point to the HSV value
corresponding, with the returned values in the following
ranges: H [0, 360], S [0, 255], V [0, 255].</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>red</parameter> :</term>
<listitem><simpara> The red channel value, returns the Hue channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>green</parameter> :</term>
<listitem><simpara> The green channel value, returns the Saturation channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>blue</parameter> :</term>
<listitem><simpara> The blue channel value, returns the Value channel
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-hsv-to-rgb-int"/>gimp_hsv_to_rgb_int ()</title>
<indexterm><primary>gimp_hsv_to_rgb_int</primary></indexterm><programlisting><link linkend="void">void</link> gimp_hsv_to_rgb_int (<link linkend="gint">gint</link> *hue,
<link linkend="gint">gint</link> *saturation,
<link linkend="gint">gint</link> *value);</programlisting>
<para>
The arguments are pointers to int, with the values pointed to in the
following ranges: H [0, 360], S [0, 255], V [0, 255].
</para>
<para>
The function changes the arguments to point to the RGB value
corresponding, with the returned values all in the range [0, 255].</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>hue</parameter> :</term>
<listitem><simpara> The hue channel, returns the red channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>saturation</parameter> :</term>
<listitem><simpara> The saturation channel, returns the green channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter> :</term>
<listitem><simpara> The value channel, returns the blue channel
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-hsl-int"/>gimp_rgb_to_hsl_int ()</title>
<indexterm><primary>gimp_rgb_to_hsl_int</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_hsl_int (<link linkend="gint">gint</link> *red,
<link linkend="gint">gint</link> *green,
<link linkend="gint">gint</link> *blue);</programlisting>
<para>
The arguments are pointers to int representing channel values in the
RGB colorspace, and the values pointed to are all in the range [0, 255].
</para>
<para>
The function changes the arguments to point to the corresponding HLS
value with the values pointed to in the following ranges: H [0, 360],
L [0, 255], S [0, 255].</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>red</parameter> :</term>
<listitem><simpara> Red channel, returns Hue channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>green</parameter> :</term>
<listitem><simpara> Green channel, returns Lightness channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>blue</parameter> :</term>
<listitem><simpara> Blue channel, returns Saturation channel
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-cmyk-int"/>gimp_rgb_to_cmyk_int ()</title>
<indexterm><primary>gimp_rgb_to_cmyk_int</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_cmyk_int (<link linkend="gint">gint</link> *red,
<link linkend="gint">gint</link> *green,
<link linkend="gint">gint</link> *blue,
<link linkend="gint">gint</link> *pullout);</programlisting>
<para>
Does a naive conversion from RGB to CMYK colorspace. A simple
formula that doesn't take any color-profiles into account is used.
The amount of black pullout how can be controlled via the <parameter>pullout</parameter>
parameter. A <parameter>pullout</parameter> value of 0 makes this a conversion to CMY.
A value of 100 causes the maximum amount of black to be pulled out.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>red</parameter> :</term>
<listitem><simpara> the red channel; returns the cyan value (0-255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>green</parameter> :</term>
<listitem><simpara> the green channel; returns the magenta value (0-255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>blue</parameter> :</term>
<listitem><simpara> the blue channel; returns the yellow value (0-255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>pullout</parameter> :</term>
<listitem><simpara> the percentage of black to pull out (0-100); returns
the black value (0-255)
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-cmyk-to-rgb-int"/>gimp_cmyk_to_rgb_int ()</title>
<indexterm><primary>gimp_cmyk_to_rgb_int</primary></indexterm><programlisting><link linkend="void">void</link> gimp_cmyk_to_rgb_int (<link linkend="gint">gint</link> *cyan,
<link linkend="gint">gint</link> *magenta,
<link linkend="gint">gint</link> *yellow,
<link linkend="gint">gint</link> *black);</programlisting>
<para>
Does a naive conversion from CMYK to RGB colorspace. A simple
formula that doesn't take any color-profiles into account is used.</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>cyan</parameter> :</term>
<listitem><simpara> the cyan channel; returns the red value (0-255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>magenta</parameter> :</term>
<listitem><simpara> the magenta channel; returns the green value (0-255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>yellow</parameter> :</term>
<listitem><simpara> the yellow channel; returns the blue value (0-255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>black</parameter> :</term>
<listitem><simpara> the black channel (0-255); doesn't change
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-l-int"/>gimp_rgb_to_l_int ()</title>
<indexterm><primary>gimp_rgb_to_l_int</primary></indexterm><programlisting><link linkend="gint">gint</link> gimp_rgb_to_l_int (<link linkend="gint">gint</link> red,
<link linkend="gint">gint</link> green,
<link linkend="gint">gint</link> blue);</programlisting>
<para>
Calculates the lightness value of an RGB triplet with the formula
L = (max(R, G, B) + min (R, G, B)) / 2</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>red</parameter> :</term>
<listitem><simpara> Red channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>green</parameter> :</term>
<listitem><simpara> Green channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>blue</parameter> :</term>
<listitem><simpara> Blue channel
</simpara></listitem></varlistentry>
<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> Luminance vaue corresponding to the input RGB value
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-hsl-to-rgb-int"/>gimp_hsl_to_rgb_int ()</title>
<indexterm><primary>gimp_hsl_to_rgb_int</primary></indexterm><programlisting><link linkend="void">void</link> gimp_hsl_to_rgb_int (<link linkend="gint">gint</link> *hue,
<link linkend="gint">gint</link> *saturation,
<link linkend="gint">gint</link> *lightness);</programlisting>
<para>
The arguments are pointers to int, with the values pointed to in the
following ranges: H [0, 360], L [0, 255], S [0, 255].
</para>
<para>
The function changes the arguments to point to the RGB value
corresponding, with the returned values all in the range [0, 255].</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>hue</parameter> :</term>
<listitem><simpara> Hue channel, returns Red channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>saturation</parameter> :</term>
<listitem><simpara> Saturation channel, returns Green channel
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>lightness</parameter> :</term>
<listitem><simpara> Lightness channel, returns Blue channel
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-rgb-to-hsv4"/>gimp_rgb_to_hsv4 ()</title>
<indexterm><primary>gimp_rgb_to_hsv4</primary></indexterm><programlisting><link linkend="void">void</link> gimp_rgb_to_hsv4 (<link linkend="guchar">guchar</link> *rgb,
<link linkend="gdouble">gdouble</link> *hue,
<link linkend="gdouble">gdouble</link> *saturation,
<link linkend="gdouble">gdouble</link> *value);</programlisting>
<para>
</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> RGB triplet, rgb[0] is red channel, rgb[1] is green,
rgb[2] is blue (0..255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>hue</parameter> :</term>
<listitem><simpara> Pointer to hue channel (0..1)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>saturation</parameter> :</term>
<listitem><simpara> Pointer to saturation channel (0..1)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter> :</term>
<listitem><simpara> Pointer to value channel (0..1)
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2>
<title><anchor id="gimp-hsv-to-rgb4"/>gimp_hsv_to_rgb4 ()</title>
<indexterm><primary>gimp_hsv_to_rgb4</primary></indexterm><programlisting><link linkend="void">void</link> gimp_hsv_to_rgb4 (<link linkend="guchar">guchar</link> *rgb,
<link linkend="gdouble">gdouble</link> hue,
<link linkend="gdouble">gdouble</link> saturation,
<link linkend="gdouble">gdouble</link> value);</programlisting>
<para>
</para>
<para>
</para><variablelist role="params">
<varlistentry><term><parameter>rgb</parameter> :</term>
<listitem><simpara> RGB triplet, rgb[0] is red channel, rgb[1] is green,
rgb[2] is blue (0..255)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>hue</parameter> :</term>
<listitem><simpara> Hue channel (0..1)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>saturation</parameter> :</term>
<listitem><simpara> Saturation channel (0..1)
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter> :</term>
<listitem><simpara> Value channel (0..1)
</simpara></listitem></varlistentry>
</variablelist></refsect2>
</refsect1>
</refentry>
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