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|
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
<title>GimpColorSpace</title>
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</tr></table>
<div class="refentry" lang="en">
<a name="libgimpcolor-GimpColorSpace"></a><div class="titlepage"></div>
<div class="refnamediv"><table width="100%"><tr>
<td valign="top">
<h2><span class="refentrytitle">GimpColorSpace</span></h2>
<p>GimpColorSpace — Utility functions which convert colors between different color models.</p>
</td>
<td valign="top" align="right"></td>
</tr></table></div>
<div class="refsynopsisdiv">
<h2>Synopsis</h2>
<pre class="synopsis">
<a href="libgimpcolor-GimpColorSpace.html#GimpHSL">GimpHSL</a>;
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-hsv">gimp_rgb_to_hsv</a> (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
<a href="libgimpcolor-GimpHSV.html#GimpHSV">GimpHSV</a> *hsv);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-hsl">gimp_rgb_to_hsl</a> (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
<a href="libgimpcolor-GimpColorSpace.html#GimpHSL">GimpHSL</a> *hsl);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-cmyk">gimp_rgb_to_cmyk</a> (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
gdouble pullout,
<a href="libgimpcolor-GimpCMYK.html#GimpCMYK">GimpCMYK</a> *cmyk);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-hsv-to-rgb">gimp_hsv_to_rgb</a> (const <a href="libgimpcolor-GimpHSV.html#GimpHSV">GimpHSV</a> *hsv,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-hsl-to-rgb">gimp_hsl_to_rgb</a> (const <a href="libgimpcolor-GimpColorSpace.html#GimpHSL">GimpHSL</a> *hsl,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-cmyk-to-rgb">gimp_cmyk_to_rgb</a> (const <a href="libgimpcolor-GimpCMYK.html#GimpCMYK">GimpCMYK</a> *cmyk,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-hwb">gimp_rgb_to_hwb</a> (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
gdouble *hue,
gdouble *whiteness,
gdouble *blackness);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-hwb-to-rgb">gimp_hwb_to_rgb</a> (gdouble hue,
gdouble whiteness,
gdouble blackness,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-hsv-int">gimp_rgb_to_hsv_int</a> (gint *red,
gint *green,
gint *blue);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-hsv-to-rgb-int">gimp_hsv_to_rgb_int</a> (gint *hue,
gint *saturation,
gint *value);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-hsl-int">gimp_rgb_to_hsl_int</a> (gint *red,
gint *green,
gint *blue);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-cmyk-int">gimp_rgb_to_cmyk_int</a> (gint *red,
gint *green,
gint *blue,
gint *pullout);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-cmyk-to-rgb-int">gimp_cmyk_to_rgb_int</a> (gint *cyan,
gint *magenta,
gint *yellow,
gint *black);
gint <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-l-int">gimp_rgb_to_l_int</a> (gint red,
gint green,
gint blue);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-hsl-to-rgb-int">gimp_hsl_to_rgb_int</a> (gint *hue,
gint *saturation,
gint *lightness);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-rgb-to-hsv4">gimp_rgb_to_hsv4</a> (guchar *rgb,
gdouble *hue,
gdouble *saturation,
gdouble *value);
void <a href="libgimpcolor-GimpColorSpace.html#gimp-hsv-to-rgb4">gimp_hsv_to_rgb4</a> (guchar *rgb,
gdouble hue,
gdouble saturation,
gdouble value);
</pre>
</div>
<div class="refsect1" lang="en">
<a name="id2515582"></a><h2>Description</h2>
<p>
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.
</p>
</div>
<div class="refsect1" lang="en">
<a name="id2515597"></a><h2>Details</h2>
<div class="refsect2" lang="en">
<a name="id2515603"></a><h3>
<a name="GimpHSL"></a>GimpHSL</h3>
<a class="indexterm" name="id2515613"></a><pre class="programlisting">typedef struct {
gdouble h, s, l, a;
} GimpHSL;
</pre>
<p>
</p>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2515634"></a><h3>
<a name="gimp-rgb-to-hsv"></a>gimp_rgb_to_hsv ()</h3>
<a class="indexterm" name="id2515645"></a><pre class="programlisting">void gimp_rgb_to_hsv (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
<a href="libgimpcolor-GimpHSV.html#GimpHSV">GimpHSV</a> *hsv);</pre>
<p>
Does a conversion from RGB to HSV (Hue, Saturation,
Value) colorspace.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> A color value in the RGB colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>hsv</code></em> :</span></td>
<td> The value converted to the HSV colorspace
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2515716"></a><h3>
<a name="gimp-rgb-to-hsl"></a>gimp_rgb_to_hsl ()</h3>
<a class="indexterm" name="id2515726"></a><pre class="programlisting">void gimp_rgb_to_hsl (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
<a href="libgimpcolor-GimpColorSpace.html#GimpHSL">GimpHSL</a> *hsl);</pre>
<p>
Convert an RGB color value to a HSL (Hue, Saturation, Lightness)
color value.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> A color value in the RGB colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>hsl</code></em> :</span></td>
<td> The value converted to HSL
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2515798"></a><h3>
<a name="gimp-rgb-to-cmyk"></a>gimp_rgb_to_cmyk ()</h3>
<a class="indexterm" name="id2515808"></a><pre class="programlisting">void gimp_rgb_to_cmyk (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
gdouble pullout,
<a href="libgimpcolor-GimpCMYK.html#GimpCMYK">GimpCMYK</a> *cmyk);</pre>
<p>
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 <em class="parameter"><code>pullout</code></em>
parameter. A <em class="parameter"><code>pullout</code></em> value of 0 makes this a conversion to CMY.
A value of 1 causes the maximum amount of black to be pulled out.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> A value in the RGB colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>pullout</code></em> :</span></td>
<td> A scaling value (0-1) indicating how much black should be
pulled out
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>cmyk</code></em> :</span></td>
<td> The input value naively converted to the CMYK colorspace
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2564470"></a><h3>
<a name="gimp-hsv-to-rgb"></a>gimp_hsv_to_rgb ()</h3>
<a class="indexterm" name="id2564479"></a><pre class="programlisting">void gimp_hsv_to_rgb (const <a href="libgimpcolor-GimpHSV.html#GimpHSV">GimpHSV</a> *hsv,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);</pre>
<p>
Converts a color value from HSV to RGB colorspace</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>hsv</code></em> :</span></td>
<td> A color value in the HSV colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> The returned RGB value.
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2564542"></a><h3>
<a name="gimp-hsl-to-rgb"></a>gimp_hsl_to_rgb ()</h3>
<a class="indexterm" name="id2564551"></a><pre class="programlisting">void gimp_hsl_to_rgb (const <a href="libgimpcolor-GimpColorSpace.html#GimpHSL">GimpHSL</a> *hsl,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);</pre>
<p>
Convert a HSL color value to an RGB color value.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>hsl</code></em> :</span></td>
<td> A color value in the HSL colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> The value converted to a value in the RGB colorspace
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2564616"></a><h3>
<a name="gimp-cmyk-to-rgb"></a>gimp_cmyk_to_rgb ()</h3>
<a class="indexterm" name="id2564625"></a><pre class="programlisting">void gimp_cmyk_to_rgb (const <a href="libgimpcolor-GimpCMYK.html#GimpCMYK">GimpCMYK</a> *cmyk,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);</pre>
<p>
Does a simple transformation from the CMYK colorspace to the RGB
colorspace, without taking color profiles into account.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>cmyk</code></em> :</span></td>
<td> A color value in the CMYK colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> The value converted to the RGB colorspace
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2564699"></a><h3>
<a name="gimp-rgb-to-hwb"></a>gimp_rgb_to_hwb ()</h3>
<a class="indexterm" name="id2564709"></a><pre class="programlisting">void gimp_rgb_to_hwb (const <a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb,
gdouble *hue,
gdouble *whiteness,
gdouble *blackness);</pre>
<p>
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.
</p>
<p>
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.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> A color value in the RGB colorspace
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>hue</code></em> :</span></td>
<td> The hue value of the above color, in the range 0 to 6
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>whiteness</code></em> :</span></td>
<td> The whiteness value of the above color, in the range 0 to 1
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>blackness</code></em> :</span></td>
<td> The blackness value of the above color, in the range 0 to 1
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2564834"></a><h3>
<a name="gimp-hwb-to-rgb"></a>gimp_hwb_to_rgb ()</h3>
<a class="indexterm" name="id2564844"></a><pre class="programlisting">void gimp_hwb_to_rgb (gdouble hue,
gdouble whiteness,
gdouble blackness,
<a href="libgimpcolor-GimpRGB.html#GimpRGB">GimpRGB</a> *rgb);</pre>
<p>
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].</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>hue</code></em> :</span></td>
<td> A hue value, in the range 0 to 6
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>whiteness</code></em> :</span></td>
<td> A whiteness value, in the range 0 to 1
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>blackness</code></em> :</span></td>
<td> A blackness value, in the range 0 to 1
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> The above color converted to the RGB colorspace
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2564961"></a><h3>
<a name="gimp-rgb-to-hsv-int"></a>gimp_rgb_to_hsv_int ()</h3>
<a class="indexterm" name="id2564971"></a><pre class="programlisting">void gimp_rgb_to_hsv_int (gint *red,
gint *green,
gint *blue);</pre>
<p>
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].
</p>
<p>
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].</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>red</code></em> :</span></td>
<td> The red channel value, returns the Hue channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>green</code></em> :</span></td>
<td> The green channel value, returns the Saturation channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>blue</code></em> :</span></td>
<td> The blue channel value, returns the Value channel
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565073"></a><h3>
<a name="gimp-hsv-to-rgb-int"></a>gimp_hsv_to_rgb_int ()</h3>
<a class="indexterm" name="id2565083"></a><pre class="programlisting">void gimp_hsv_to_rgb_int (gint *hue,
gint *saturation,
gint *value);</pre>
<p>
The arguments are pointers to int, with the values pointed to in the
following ranges: H [0, 360], S [0, 255], V [0, 255].
</p>
<p>
The function changes the arguments to point to the RGB value
corresponding, with the returned values all in the range [0, 255].</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>hue</code></em> :</span></td>
<td> The hue channel, returns the red channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>saturation</code></em> :</span></td>
<td> The saturation channel, returns the green channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>value</code></em> :</span></td>
<td> The value channel, returns the blue channel
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565184"></a><h3>
<a name="gimp-rgb-to-hsl-int"></a>gimp_rgb_to_hsl_int ()</h3>
<a class="indexterm" name="id2565194"></a><pre class="programlisting">void gimp_rgb_to_hsl_int (gint *red,
gint *green,
gint *blue);</pre>
<p>
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].
</p>
<p>
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].</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>red</code></em> :</span></td>
<td> Red channel, returns Hue channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>green</code></em> :</span></td>
<td> Green channel, returns Lightness channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>blue</code></em> :</span></td>
<td> Blue channel, returns Saturation channel
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565295"></a><h3>
<a name="gimp-rgb-to-cmyk-int"></a>gimp_rgb_to_cmyk_int ()</h3>
<a class="indexterm" name="id2565304"></a><pre class="programlisting">void gimp_rgb_to_cmyk_int (gint *red,
gint *green,
gint *blue,
gint *pullout);</pre>
<p>
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 <em class="parameter"><code>pullout</code></em>
parameter. A <em class="parameter"><code>pullout</code></em> value of 0 makes this a conversion to CMY.
A value of 100 causes the maximum amount of black to be pulled out.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>red</code></em> :</span></td>
<td> the red channel; returns the cyan value (0-255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>green</code></em> :</span></td>
<td> the green channel; returns the magenta value (0-255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>blue</code></em> :</span></td>
<td> the blue channel; returns the yellow value (0-255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>pullout</code></em> :</span></td>
<td> the percentage of black to pull out (0-100); returns
the black value (0-255)
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565437"></a><h3>
<a name="gimp-cmyk-to-rgb-int"></a>gimp_cmyk_to_rgb_int ()</h3>
<a class="indexterm" name="id2565446"></a><pre class="programlisting">void gimp_cmyk_to_rgb_int (gint *cyan,
gint *magenta,
gint *yellow,
gint *black);</pre>
<p>
Does a naive conversion from CMYK to RGB colorspace. A simple
formula that doesn't take any color-profiles into account is used.</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>cyan</code></em> :</span></td>
<td> the cyan channel; returns the red value (0-255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>magenta</code></em> :</span></td>
<td> the magenta channel; returns the green value (0-255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>yellow</code></em> :</span></td>
<td> the yellow channel; returns the blue value (0-255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>black</code></em> :</span></td>
<td> the black channel (0-255); doesn't change
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565564"></a><h3>
<a name="gimp-rgb-to-l-int"></a>gimp_rgb_to_l_int ()</h3>
<a class="indexterm" name="id2565574"></a><pre class="programlisting">gint gimp_rgb_to_l_int (gint red,
gint green,
gint blue);</pre>
<p>
Calculates the lightness value of an RGB triplet with the formula
L = (max(R, G, B) + min (R, G, B)) / 2</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>red</code></em> :</span></td>
<td> Red channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>green</code></em> :</span></td>
<td> Green channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>blue</code></em> :</span></td>
<td> Blue channel
</td>
</tr>
<tr>
<td>
<span class="term"><span class="emphasis"><em>Returns</em></span> :</span></td>
<td> Luminance vaue corresponding to the input RGB value
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565679"></a><h3>
<a name="gimp-hsl-to-rgb-int"></a>gimp_hsl_to_rgb_int ()</h3>
<a class="indexterm" name="id2565689"></a><pre class="programlisting">void gimp_hsl_to_rgb_int (gint *hue,
gint *saturation,
gint *lightness);</pre>
<p>
The arguments are pointers to int, with the values pointed to in the
following ranges: H [0, 360], L [0, 255], S [0, 255].
</p>
<p>
The function changes the arguments to point to the RGB value
corresponding, with the returned values all in the range [0, 255].</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>hue</code></em> :</span></td>
<td> Hue channel, returns Red channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>saturation</code></em> :</span></td>
<td> Saturation channel, returns Green channel
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>lightness</code></em> :</span></td>
<td> Lightness channel, returns Blue channel
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565789"></a><h3>
<a name="gimp-rgb-to-hsv4"></a>gimp_rgb_to_hsv4 ()</h3>
<a class="indexterm" name="id2565800"></a><pre class="programlisting">void gimp_rgb_to_hsv4 (guchar *rgb,
gdouble *hue,
gdouble *saturation,
gdouble *value);</pre>
<p>
</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> RGB triplet, rgb[0] is red channel, rgb[1] is green,
rgb[2] is blue (0..255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>hue</code></em> :</span></td>
<td> Pointer to hue channel (0..1)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>saturation</code></em> :</span></td>
<td> Pointer to saturation channel (0..1)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>value</code></em> :</span></td>
<td> Pointer to value channel (0..1)
</td>
</tr>
</tbody>
</table></div>
</div>
<hr>
<div class="refsect2" lang="en">
<a name="id2565915"></a><h3>
<a name="gimp-hsv-to-rgb4"></a>gimp_hsv_to_rgb4 ()</h3>
<a class="indexterm" name="id2565926"></a><pre class="programlisting">void gimp_hsv_to_rgb4 (guchar *rgb,
gdouble hue,
gdouble saturation,
gdouble value);</pre>
<p>
</p>
<p>
</p>
<div class="variablelist"><table border="0">
<col align="left" valign="top">
<tbody>
<tr>
<td>
<span class="term"><em class="parameter"><code>rgb</code></em> :</span></td>
<td> RGB triplet, rgb[0] is red channel, rgb[1] is green,
rgb[2] is blue (0..255)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>hue</code></em> :</span></td>
<td> Hue channel (0..1)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>saturation</code></em> :</span></td>
<td> Saturation channel (0..1)
</td>
</tr>
<tr>
<td>
<span class="term"><em class="parameter"><code>value</code></em> :</span></td>
<td> Value channel (0..1)
</td>
</tr>
</tbody>
</table></div>
</div>
</div>
</div>
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