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<h1 class="refname">Gmagick::quantizeimages</h1>
<p class="verinfo">(PECL gmagick >= Unknown)</p><p class="refpurpose"><span class="refname">Gmagick::quantizeimages</span> — <span class="dc-title">The quantizeimages purpose</span></p>
</div>
<div class="refsect1 description" id="refsect1-gmagick.quantizeimages-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><span class="type void">void</span></span> <span class="methodname"><strong>Gmagick::quantizeimages</strong></span>
( <span class="methodparam"><span class="type">int</span> <code class="parameter">$numColors</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$colorspace</code></span>
, <span class="methodparam"><span class="type">int</span> <code class="parameter">$treeDepth</code></span>
, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$dither</code></span>
, <span class="methodparam"><span class="type">bool</span> <code class="parameter">$measureError</code></span>
)</div>
<p class="para rdfs-comment">
Analyzes the colors within a sequence of images and chooses a fixed number of
colors to represent the image. The goal of the algorithm is to minimize the
color difference between the input and output image while minimizing the processing time.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-gmagick.quantizeimages-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">numColors</code></em></span>
<dd>
<p class="para">
The number of colors.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">colorspace</code></em></span>
<dd>
<p class="para">
Perform color reduction in this colorspace, typically RGBColorspace.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">treeDepth</code></em></span>
<dd>
<p class="para">
Normally, this integer value is zero or one. A zero or one tells Quantize
to choose a optimal tree depth of Log4(number_colors).% A tree of this depth generally
allows the best representation of the reference image with the least amount of memory
and the fastest computational speed. In some cases, such as an image with low color
dispersion (a few number of colors), a value other than Log4(number_colors) is required.
To expand the color tree completely, use a value of 8.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">dither</code></em></span>
<dd>
<p class="para">
A value other than zero distributes the difference between an original image and the corresponding color reduced algorithm to neighboring pixels along a Hilbert curve.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">measureError</code></em></span>
<dd>
<p class="para">
A value other than zero measures the difference between the original and quantized images. This difference is the total quantization error. The error is computed by summing over all pixels in an image the distance squared in RGB space between each reference pixel value and its quantized value.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-gmagick.quantizeimages-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
The Gmagick object on success
</p>
</div>
<div class="refsect1 errors" id="refsect1-gmagick.quantizeimages-errors">
<h3 class="title">Errors/Exceptions</h3>
<p class="para">
Throws an
<strong class="classname">GmagickException</strong> on error.
</p>
</div>
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