<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<title>Get the index of the closest color to the specified color</title>
</head>
<body><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="function.imagecolorat.html">imagecolorat</a></div>
<div class="next" style="text-align: right; float: right;"><a href="function.imagecolorclosestalpha.html">imagecolorclosestalpha</a></div>
<div class="up"><a href="ref.image.html">GD and Image Functions</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div><hr /><div id="function.imagecolorclosest" class="refentry">
<div class="refnamediv">
<h1 class="refname">imagecolorclosest</h1>
<p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">imagecolorclosest</span> — <span class="dc-title">Get the index of the closest color to the specified color</span></p>
</div>
<div class="refsect1 description" id="refsect1-function.imagecolorclosest-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">int</span> <span class="methodname"><strong>imagecolorclosest</strong></span>
( <span class="methodparam"><span class="type">resource</span> <code class="parameter">$image</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$red</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$green</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$blue</code></span>
)</div>
<p class="para rdfs-comment">
Returns the index of the color in the palette of the image which
is "closest" to the specified <acronym title="Red-Green-Blue">RGB</acronym> value.
</p>
<p class="para">
The "distance" between the desired color and each color in the
palette is calculated as if the <acronym title="Red-Green-Blue">RGB</acronym> values
represented points in three-dimensional space.
</p>
<p class="para">If you created the image from a file, only colors used in the image are resolved. Colors present only in the palette are not resolved.</p>
</div>
<div class="refsect1 parameters" id="refsect1-function.imagecolorclosest-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">
image</code></em></span><dd>
<p class="para">An image resource, returned by one of the image creation functions,
such as <span class="function"><a href="function.imagecreatetruecolor.html" class="function">imagecreatetruecolor()</a></span>.</p></dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">red</code></em></span>
<dd>
<p class="para">Value of red component.</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">green</code></em></span>
<dd>
<p class="para">Value of green component.</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">blue</code></em></span>
<dd>
<p class="para">Value of blue component.</p>
</dd>
</dt>
</dl>
The colors parameters are integers between 0 and 255 or hexadecimals
between 0x00 and 0xFF.
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-function.imagecolorclosest-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns the index of the closest color, in the palette of the image, to
the specified one
</p>
</div>
<div class="refsect1 examples" id="refsect1-function.imagecolorclosest-examples">
<h3 class="title">Examples</h3>
<p class="para">
<div class="example" id="example-3187">
<p><strong>Example #1 Search for a set of colors in an image</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #FF8000">// Start with an image and convert it to a palette-based image<br /></span><span style="color: #0000BB">$im </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecreatefrompng</span><span style="color: #007700">(</span><span style="color: #DD0000">'figures/imagecolorclosest.png'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">imagetruecolortopalette</span><span style="color: #007700">(</span><span style="color: #0000BB">$im</span><span style="color: #007700">, </span><span style="color: #0000BB">false</span><span style="color: #007700">, </span><span style="color: #0000BB">255</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Search colors (RGB)<br /></span><span style="color: #0000BB">$colors </span><span style="color: #007700">= array(<br /> array(</span><span style="color: #0000BB">254</span><span style="color: #007700">, </span><span style="color: #0000BB">145</span><span style="color: #007700">, </span><span style="color: #0000BB">154</span><span style="color: #007700">),<br /> array(</span><span style="color: #0000BB">153</span><span style="color: #007700">, </span><span style="color: #0000BB">145</span><span style="color: #007700">, </span><span style="color: #0000BB">188</span><span style="color: #007700">),<br /> array(</span><span style="color: #0000BB">153</span><span style="color: #007700">, </span><span style="color: #0000BB">90</span><span style="color: #007700">, </span><span style="color: #0000BB">145</span><span style="color: #007700">),<br /> array(</span><span style="color: #0000BB">255</span><span style="color: #007700">, </span><span style="color: #0000BB">137</span><span style="color: #007700">, </span><span style="color: #0000BB">92</span><span style="color: #007700">)<br />);<br /><br /></span><span style="color: #FF8000">// Loop through each search and find the closest color in the palette.<br />// Return the search number, the search RGB and the converted RGB match<br /></span><span style="color: #007700">foreach(</span><span style="color: #0000BB">$colors </span><span style="color: #007700">as </span><span style="color: #0000BB">$id </span><span style="color: #007700">=> </span><span style="color: #0000BB">$rgb</span><span style="color: #007700">)<br />{<br /> </span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecolorclosest</span><span style="color: #007700">(</span><span style="color: #0000BB">$im</span><span style="color: #007700">, </span><span style="color: #0000BB">$rgb</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">], </span><span style="color: #0000BB">$rgb</span><span style="color: #007700">[</span><span style="color: #0000BB">1</span><span style="color: #007700">], </span><span style="color: #0000BB">$rgb</span><span style="color: #007700">[</span><span style="color: #0000BB">2</span><span style="color: #007700">]);<br /> </span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #0000BB">imagecolorsforindex</span><span style="color: #007700">(</span><span style="color: #0000BB">$im</span><span style="color: #007700">, </span><span style="color: #0000BB">$result</span><span style="color: #007700">);<br /> </span><span style="color: #0000BB">$result </span><span style="color: #007700">= </span><span style="color: #DD0000">"(</span><span style="color: #007700">{</span><span style="color: #0000BB">$result</span><span style="color: #007700">[</span><span style="color: #DD0000">'red'</span><span style="color: #007700">]}</span><span style="color: #DD0000">, </span><span style="color: #007700">{</span><span style="color: #0000BB">$result</span><span style="color: #007700">[</span><span style="color: #DD0000">'green'</span><span style="color: #007700">]}</span><span style="color: #DD0000">, </span><span style="color: #007700">{</span><span style="color: #0000BB">$result</span><span style="color: #007700">[</span><span style="color: #DD0000">'blue'</span><span style="color: #007700">]}</span><span style="color: #DD0000">)"</span><span style="color: #007700">;<br /><br /> echo </span><span style="color: #DD0000">"#</span><span style="color: #0000BB">$id</span><span style="color: #DD0000">: Search (</span><span style="color: #0000BB">$rgb</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">]</span><span style="color: #DD0000">, </span><span style="color: #0000BB">$rgb</span><span style="color: #007700">[</span><span style="color: #0000BB">1</span><span style="color: #007700">]</span><span style="color: #DD0000">, </span><span style="color: #0000BB">$rgb</span><span style="color: #007700">[</span><span style="color: #0000BB">2</span><span style="color: #007700">]</span><span style="color: #DD0000">); Closest match: </span><span style="color: #0000BB">$result</span><span style="color: #DD0000">.\n"</span><span style="color: #007700">;<br />}<br /><br /></span><span style="color: #0000BB">imagedestroy</span><span style="color: #007700">(</span><span style="color: #0000BB">$im</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output
something similar to:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
#0: Search (254, 145, 154); Closest match: (252, 150, 148).
#1: Search (153, 145, 188); Closest match: (148, 150, 196).
#2: Search (153, 90, 145); Closest match: (148, 90, 156).
#3: Search (255, 137, 92); Closest match: (252, 150, 92).
</pre></div>
</div>
</div>
</p>
</div>
<div class="refsect1 seealso" id="refsect1-function.imagecolorclosest-seealso">
<h3 class="title">See Also</h3>
<p class="para">
<ul class="simplelist">
<li class="member"> <span class="function"><a href="function.imagecolorexact.html" class="function" rel="rdfs-seeAlso">imagecolorexact()</a> - Get the index of the specified color</span></li>
<li class="member"> <span class="function"><a href="function.imagecolorclosestalpha.html" class="function" rel="rdfs-seeAlso">imagecolorclosestalpha()</a> - Get the index of the closest color to the specified color + alpha</span></li>
<li class="member"> <span class="function"><a href="function.imagecolorclosesthwb.html" class="function" rel="rdfs-seeAlso">imagecolorclosesthwb()</a> - Get the index of the color which has the hue, white and blackness</span></li>
</ul>
</p>
</div>
</div><hr /><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="function.imagecolorat.html">imagecolorat</a></div>
<div class="next" style="text-align: right; float: right;"><a href="function.imagecolorclosestalpha.html">imagecolorclosestalpha</a></div>
<div class="up"><a href="ref.image.html">GD and Image Functions</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div></body></html>
