<!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>Gamma-corrects an image</title>
</head>
<body><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="imagick.fximage.html">Imagick::fxImage</a></div>
<div class="next" style="text-align: right; float: right;"><a href="imagick.gaussianblurimage.html">Imagick::gaussianBlurImage</a></div>
<div class="up"><a href="class.imagick.html">Imagick</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div><hr /><div id="imagick.gammaimage" class="refentry">
<div class="refnamediv">
<h1 class="refname">Imagick::gammaImage</h1>
<p class="verinfo">(PECL imagick 2.0.0)</p><p class="refpurpose"><span class="refname">Imagick::gammaImage</span> — <span class="dc-title">Gamma-corrects an image</span></p>
</div>
<div class="refsect1 description" id="refsect1-imagick.gammaimage-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="type">bool</span> <span class="methodname"><strong>Imagick::gammaImage</strong></span>
( <span class="methodparam"><span class="type">float</span> <code class="parameter">$gamma</code></span>
[, <span class="methodparam"><span class="type">int</span> <code class="parameter">$channel</code><span class="initializer"> = Imagick::CHANNEL_ALL</span></span>
] )</div>
<p class="para rdfs-comment">
Gamma-corrects an image. The same image viewed on different devices will
have perceptual differences in the way the image's intensities are
represented on the screen. Specify individual gamma levels for the red,
green, and blue channels, or adjust all three with the gamma parameter.
Values typically range from 0.8 to 2.3.
</p>
</div>
<div class="refsect1 parameters" id="refsect1-imagick.gammaimage-parameters">
<h3 class="title">Parameters</h3>
<p class="para">
<dl>
<dt>
<span class="term"><em><code class="parameter">gamma</code></em></span>
<dd>
<p class="para">
The amount of gamma-correction.
</p>
</dd>
</dt>
<dt>
<span class="term"><em><code class="parameter">channel</code></em></span>
<dd>
<p class="para">
Provide any channel constant that is valid for your channel mode. To
apply to more than one channel, combine channeltype constants using
bitwise operators. Refer to this
list of <a href="imagick.constants.html#imagick.constants.channel" class="link">channel constants</a>.
</p>
</dd>
</dt>
</dl>
</p>
</div>
<div class="refsect1 returnvalues" id="refsect1-imagick.gammaimage-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
Returns <strong><code>TRUE</code></strong> on success.
</p>
</div>
<div class="refsect1 errors" id="refsect1-imagick.gammaimage-errors">
<h3 class="title">Errors/Exceptions</h3>
<p class="para">
Throws ImagickException on error.
</p>
</div>
</div><hr /><div class="manualnavbar" style="text-align: center;">
<div class="prev" style="text-align: left; float: left;"><a href="imagick.fximage.html">Imagick::fxImage</a></div>
<div class="next" style="text-align: right; float: right;"><a href="imagick.gaussianblurimage.html">Imagick::gaussianBlurImage</a></div>
<div class="up"><a href="class.imagick.html">Imagick</a></div>
<div class="home"><a href="index.html">PHP Manual</a></div>
</div></body></html>
