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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
<head>
<meta name="generator" content="HTML Tidy for Linux/x86 (vers 7 December 2008), see www.w3.org" />
<title>RMagick 7.1.1: class Image (instance methods p-w)</title>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii" />
<meta name="GENERATOR" content="Quanta Plus" />
<meta name="Copyright" content="Copyright (C) 2006 by Timothy P. Hunter" />
<link rel="stylesheet" type="text/css" href="css/doc.css" />
<script type="text/javascript" src="scripts/doc.js"></script>
<script type="text/javascript">
//<![CDATA[
<!-- Pre-load this image so that the browser knows how big it is. -->
<!-- Begin
flower_hat = new Image();
flower_hat.src = "ex/images/Flower_Hat.jpg";
// End -->
//]]>
</script>
<style type="text/css">
/*<![CDATA[*/
/*
* This style is used for the list of PreviewType
* constants defined for the preview method, below.
*/
#prevlist ul {
float: left;
list-style: none;
margin-bottom: 0;
}
/*
* This style is used for the list of QuantumOperator
* constants defined for the quantum_operator method, below.
*
*/
#quantum_op_list {
list-style-type: none;
}
/*]]>*/
</style>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/styles/github.min.css" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.9.0/highlight.min.js"></script>
<script>
hljs.configure({ cssSelector: "pre" });
hljs.highlightAll();
</script>
</head>
<body>
<h6 id="header">RMagick 7.1.1 User's Guide and Reference</h6>
<div class="nav">« <a href="image2.html">Prev</a> | <a href="index.html">Contents</a> | <a href="draw.html">Next</a> »</div>
<h1>
class Image <span class="superclass">< Object</span> (instance methods p-w)<br />
<span class="mixin">mixes in Comparable</span>
</h1>
<div id="toc">
<h2>Table of Contents</h2>
<h3>instance methods</h3>
<div>
<div class="toccol">
<ul>
<li><a href="#palette_q">palette?</a></li>
<li><a href="#paint_transparent">paint_transparent</a></li>
<li><a href="#pixel_color">pixel_color</a></li>
<li><a href="#polaroid">polaroid</a></li>
<li><a href="#posterize">posterize</a></li>
<li><a href="#preview">preview</a></li>
<li><a href="#profile_bang">profile!</a></li>
<li><a href="#properties">properties</a></li>
<li><a href="#quantize">quantize</a></li>
<li><a href="#quantum_operator">quantum_operator</a></li>
<li><a href="#radial_blur">radial_blur</a></li>
<li><a href="#radial_blur_channel">radial_blur_channel</a></li>
<li><a href="#raise">raise</a></li>
<li>
<a href="#random_threshold_channel">random_threshold_channel</a>
</li>
<li><a href="#recolor">recolor</a></li>
<li><a href="#reduce_noise">reduce_noise</a></li>
<li><a href="#remap">remap</a></li>
<li><a href="#resample">resample</a></li>
<li><a href="#resize">resize</a></li>
<li><a href="#resize_bang">resize!</a></li>
<li><a href="#resize_to_fill">resize_to_fill</a></li>
<li><a href="#resize_to_fill_bang">resize_to_fill!</a></li>
<li><a href="#resize_to_fit">resize_to_fit</a></li>
<li><a href="#resize_to_fit_bang">resize_to_fit!</a></li>
<li><a href="#roll">roll</a></li>
<li><a href="#rotate">rotate</a></li>
<li><a href="#rotate_bang">rotate!</a></li>
</ul>
</div>
<div class="toccol">
<ul>
<li><a href="#sample">sample</a></li>
<li><a href="#sample_bang">sample!</a></li>
<li><a href="#scale">scale</a></li>
<li><a href="#scale_bang">scale!</a></li>
<li><a href="#segment">segment</a></li>
<li>
<a href="#selective_blur_channel">selective_blur_channel</a>
</li>
<li><a href="#separate">separate</a></li>
<li><a href="#sepiatone">sepiatone</a></li>
<li><a href="#set_channel_depth">set_channel_depth</a></li>
<li><a href="#shade">shade</a></li>
<li><a href="#shadow">shadow</a></li>
<li><a href="#sharpen">sharpen</a></li>
<li><a href="#sharpen_channel">sharpen_channel</a></li>
<li><a href="#shave">shave</a></li>
<li><a href="#shave_bang">shave!</a></li>
<li><a href="#shear">shear</a></li>
<li>
<a href="#sigmoidal_contrast_channel">sigmoidal_contrast_channel</a>
</li>
<li><a href="#signature">signature</a></li>
<li><a href="#sketch">sketch</a></li>
<li><a href="#solarize">solarize</a></li>
<li><a href="#sparse_color">sparse_color</a></li>
<li><a href="#splice">splice</a></li>
<li><a href="#spread">spread</a></li>
<li><a href="#stegano">stegano</a></li>
<li><a href="#stereo">stereo</a></li>
<li><a href="#store_pixels">store_pixels</a></li>
<li><a href="#strip_bang">strip!</a></li>
</ul>
</div>
<div class="toccol">
<ul>
<li><a href="#swirl">swirl</a></li>
<li><a href="#sync_profiles">sync_profiles</a></li>
<li>
<a href="#texture_fill_to_border">texture_fill_to_border</a>
</li>
<li><a href="#texture_floodfill">texture_floodfill</a></li>
<li><a href="#threshold">threshold</a></li>
<li><a href="#thumbnail">thumbnail</a></li>
<li><a href="#thumbnail_bang">thumbnail!</a></li>
<li><a href="#to_blob">to_blob</a></li>
<li><a href="#to_color">to_color</a></li>
<li><a href="#transparent">transparent</a></li>
<li><a href="#transparent_chroma">transparent_chroma</a></li>
<li><a href="#transpose">transpose</a></li>
<li><a href="#transpose_bang">transpose!</a></li>
<li><a href="#transverse">transverse</a></li>
<li><a href="#transverse_bang">transverse!</a></li>
<li><a href="#trim">trim</a></li>
<li><a href="#trim_bang">trim!</a></li>
<li><a href="#unique_colors">unique_colors</a></li>
<li><a href="#unsharp_mask">unsharp_mask</a></li>
<li><a href="#unsharp_mask_channel">unsharp_mask_channel</a></li>
<li><a href="#view">view</a></li>
<li><a href="#vignette">vignette</a></li>
<li><a href="#watermark">watermark</a></li>
<li><a href="#wave">wave</a></li>
<li><a href="#wet_floor">wet_floor</a></li>
<li><a href="#white_threshold">white_threshold</a></li>
<li><a href="#write">write</a></li>
</ul>
</div>
</div>
</div>
<h2 class="methods">instance methods</h2>
<div class="sig">
<h3 id="palette_q">palette?</h3>
<p><span class="arg">img</span>.palette? -> true or false</p>
</div>
<div class="desc">
<h4>Description</h4>
<p class="imquote">
Returns true if the image is
<a href="constants.html#ClassType">PseudoClass</a> and has 256 unique colors or less.
</p>
<h4>Returns</h4>
<p>true or false</p>
<h4>Magick API</h4>
<p>IsPaletteImage</p>
</div>
<div class="sig">
<h3 id="paint_transparent">paint_transparent</h3>
<p>
<span class="arg">img</span>.paint_transparent(<span class="arg">color</span>, <span class="arg">opacity</span>=TransparentOpacity,
<span class="arg">invert</span>=false, <span class="arg">fuzz</span>=<span class="arg">img</span>.fuzz) ->
<em>image</em>
</p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
Changes the opacity value of all the pixels that match
<span class="arg">color</span> to the value specified by <span class="arg">opacity</span>. If <span class="arg">invert</span> is true, changes the
pixels that don't match <span class="arg">color</span>.
</p>
<h4>Arguments</h4>
<dl>
<dt>color</dt>
<dd>Either a <a href="imusage.html#color_names">color name</a> or a <a href="struct.html#Pixel">pixel</a>.</dd>
<dt>opacity</dt>
<dd>
The new opacity value, either an
<a href="constants.html#Opacity">opacity</a> value or a number between 0 and QuantumRange. The default is TransparentOpacity.
</dd>
<dt>invert</dt>
<dd>If true, changes all the pixels that are <em>not</em> the target color.</dd>
<dt>fuzz</dt>
<dd>By default the pixel must match exactly, but you can specify a tolerance level by passing a positive value.</dd>
</dl>
<h4>Returns</h4>
<p>A new image</p>
<h4>See also</h4>
<p>
<a href="image2.html#matte_replace">matte_replace</a>, <a href="draw.html#matte">Draw#matte</a>,
<a href="#transparent">transparent</a>
</p>
<h4>Magick API</h4>
<p>TransparentPaintImage</p>
</div>
<div class="sig">
<h3 id="pixel_color">pixel_color</h3>
<p>
<span class="arg">img</span>.pixel_color(<span class="arg">x</span>, <span class="arg">y</span>[, <span class="arg">new_color</span>]) ->
<em>pixel</em>
</p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
Returns the color of the pixel at <span class="arg">x</span>, <span class="arg">y</span>. Optionally, changes the color of the pixel to a new color.
</p>
<p>If new_color is specified, pixel_color changes the image type to DirectClass if necessary.</p>
<h4>Arguments</h4>
<dl>
<dt>x, y</dt>
<dd>The x- and y-coordinates of the pixel.</dd>
<dt>new_color</dt>
<dd>
If specified, the pixel is set to this color. May be either a
<a href="imusage.html#color_names">color name</a> or a <a href="struct.html#Pixel">Pixel</a>.
</dd>
</dl>
<h4>Returns</h4>
A <a href="struct.html#Pixel">Pixel</a> having the RGB values of the specified pixel.
<h4>Example</h4>
<pre class="language-ruby">old = image.pixel_color(20,40,"white")</pre>
<h4>Magick API</h4>
<p>AcquireImagePixels</p>
</div>
<div class="sig">
<h3 id="polaroid">polaroid</h3>
<p><span class="arg">img</span>.polaroid(angle=-5.0) [ <span class="arg">{ optional arguments }</span> ] -> image</p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
Produce an image that looks like a Polaroid® instant picture. If the image has a "Caption" <a href="image1.html#aset">property</a>, the value is
used as a caption.
</p>
<p>
Optional arguments may be specified in a block associated with the method. These arguments control the shadow color and how the label is rendered. By
default the shadow color is gray75. To specify a different shadow color, use <code>options.shadow_color</code>. To specify a different border color
(that is, the color of the image border) use <code>options.border_color</code>. Both of these methods accept either a
<a href="imusage.html#color_names">color name</a> or a <a href="struct.html#Pixel">Pixel</a> argument.
</p>
<p>
The following <a href="draw.html#annotate">annotate</a> attributes control the label rendering: <a href="draw.html#align_eq">align</a>,
<a href="draw.html#decorate_eq">decorate</a>, <a href="draw.html#density_eq">density</a>, <a href="draw.html#encoding_eq">encoding</a>,
<a href="draw.html#fill_eq">fill</a>, <a href="draw.html#font_eq">font</a>, <a href="draw.html#font_family_eq">font_family</a>,
<a href="draw.html#font_stretch_eq">font_stretch</a>, <a href="draw.html#font_style_eq">font_style</a>,
<a href="draw.html#font_weight_eq">font_weight</a>, <a href="draw.html#gravity_eq">gravity</a>, <a href="draw.html#pointsize_eq">pointsize</a>,
<a href="draw.html#stroke_eq">stroke</a>, <a href="draw.html#stroke_width_eq">stroke_width</a>,
<a href="draw.html#text_antialias_eq">text_antialias</a>, <a href="draw.html#undercolor_eq">undercolor</a>.
</p>
<pre class="language-ruby">
img.polaroid do |options|
options.shadow_color = "gray40"
options.pointsize = 12
end
</pre>
<h4>Arguments</h4>
<dl>
<dt>angle</dt>
<dd>The resulting image is rotated by this amount, measured in degrees. The default is -5.0.</dd>
</dl>
<h4>Example</h4>
<p>
<a href="javascript:popup('polaroid.rb.html')"><img src="ex/polaroid.jpg" alt="polaroid example" /></a>
</p>
<h4>Magick API</h4>
<p>PolaroidImage</p>
<h4>Notes</h4>
<p>"Polaroid" and the other names of products of Polaroid Corporation are trademarks of Polaroid Corporation.</p>
</div>
<div class="sig">
<h3 id="posterize">posterize</h3>
<p><span class="arg">img</span>.posterize(<span class="arg">levels</span>=4, <span class="arg">dither</span>=false) -> <em>image</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p class="imquote">Reduces the image to a limited number of colors for a "poster" effect.</p>
<h4>Arguments</h4>
<dl>
<dt>levels</dt>
<dd>
<span class="imquote">Number of color levels allowed in each channel. Very low values (2, 3, or 4) have the most visible effect.</span>
The default is 4.
</dd>
<dt>dither</dt>
<dd>If true, dither the image. The default is false.</dd>
</dl>
<h4>Returns</h4>
<p>A new image</p>
<h4>Example</h4>
<p class="rollover">
<a href="javascript:popup('posterize.rb.html')"
><img
src="ex/posterize.jpg"
alt="posterize example"
onmouseover="this.src = 'ex/images/Flower_Hat.jpg'"
onmouseout="this.src = 'ex/posterize.jpg'"
title="Click to see the example script"
/></a>
<img src="ex/images/spin.gif" alt="" class="spin" title="Mouse over the example to see the original image" />
</p>
<h4>See also</h4>
<p>
<a href="image2.html#ordered_dither">ordered_dither</a>,
<a href="image3.html#quantize">quantize</a>
</p>
<h4>Magick API</h4>
<p>PosterizeImage</p>
</div>
<div class="sig">
<h3 id="preview">preview</h3>
<p><span class="arg">img</span>.preview(<span class="arg">preview</span>) -> <em>image</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
Creates an image that contains 9 small versions of the receiver image. The center image is the unchanged receiver. The other 8 images are variations
created by transforming the receiver according to the specified preview type with varying parameters.
</p>
<p>A preview image is an easy way to "try out" a transformation method.</p>
<h4>Arguments</h4>
<p>One of the following PreviewType constants:</p>
<div id="prevlist">
<ul>
<li>RotatePreview</li>
<li>ShearPreview</li>
<li>RollPreview</li>
<li>HuePreview</li>
<li>SaturationPreview</li>
<li>BrightnessPreview</li>
<li>GammaPreview</li>
<li>SpiffPreview</li>
<li>DullPreview</li>
<li>GrayscalePreview</li>
<li>QuantizePreview</li>
<li>DespecklePreview</li>
<li>ReduceNoisePreview</li>
<li>AddNoisePreview</li>
<li>SharpenPreview</li>
</ul>
<ul>
<li>BlurPreview</li>
<li>ThresholdPreview</li>
<li>EdgeDetectPreview</li>
<li>SpreadPreview</li>
<li>SolarizePreview</li>
<li>ShadePreview</li>
<li>RaisePreview</li>
<li>SegmentPreview</li>
<li>SwirlPreview</li>
<li>ImplodePreview</li>
<li>WavePreview</li>
<li>OilPaintPreview</li>
<li>CharcoalDrawingPreview</li>
<li>JPEGPreview</li>
</ul>
</div>
<div style="clear: both"></div>
<h4>Returns</h4>
<p>A new image</p>
<h4>Example</h4>
<p>This half-size preview demonstrates the SolarizePreview argument.</p>
<p>
<a href="javascript:popup('preview.rb.html')"
><img src="ex/preview_SolarizePreview.jpg" alt="preview example" title="Click to see the example script"
/></a>
</p>
<h4>Magick API</h4>
<p>PreviewImage</p>
</div>
<div class="sig">
<h3 id="profile_bang">profile!</h3>
<p><span class="arg">img</span>.profile!(<span class="arg">name</span>, <span class="arg">profile</span>) -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
<span class="imquote">Adds or removes an ICM, IPTC, or generic profile from an image.</span>
If <code>profile</code> is <code>nil</code>, the specified profile is removed from the image. Use <code>profile('*', nil)</code> to remove all profiles
from the image.
</p>
<h4>Arguments</h4>
<dl>
<dt>name</dt>
<dd>The profile name, or "*" to represent all the profiles in the image.</dd>
<dt>profile</dt>
<dd>The profile value, or <code>nil</code> to cause the profile to be removed.</dd>
</dl>
<h4>Returns</h4>
<p>self</p>
<h4>See also</h4>
<p>
<a href="image1.html#add_profile">add_profile</a> and <a href="image1.html#delete_profile">delete_profile</a> perform very similar functions. However,
<code>add_profile</code> accepts the name of a profile file on disk instead of the profile data itself and, if the file contains more than one profile,
will load all the profiles at once.
</p>
<h4>Magick API</h4>
<p>ProfileImage</p>
<h4>Notes</h4>
<p>
ImageMagick does not automatically remove profiles when resizing images. If you are trying to make your JPEG thumbnail images as small as possible, use
<code>profile!</code> to remove any profiles from the image as well. Also see <a href="#strip_bang">strip!</a>
</p>
</div>
<div class="sig">
<h3 id="properties">properties</h3>
<p><span class="arg">img</span>.properties <span class="arg">[ {|name,value| block} ]</span> -> <em>hash</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
If called with an associated block, <code>properties</code> runs the block once for each property defined for the image. The block arguments are the
property name and its value. If there is no block, <code>properties</code> returns a hash with one element for each property. The hash key is the
property name and the associated value is the property value.
</p>
<h4>Returns</h4>
<p>
If called without a block, returns a hash, otherwise returns
<code>self</code>.
</p>
<h4>See also</h4>
<p>
<a href="image1.html#aref">[ ]</a>,
<a href="image1.html#aset">[ ]=</a>
</p>
<h4>Note</h4>
<p>The EXIF property is not created until the first time an EXIF tag or entry number is referenced.</p>
</div>
<div class="sig">
<h3 id="quantize">quantize</h3>
<p>
<span class="arg">img</span>.quantize(<span class="arg">number_colors</span>=256, <span class="arg">colorspace</span>=RGBColorspace,
<span class="arg">dither</span>=<code>RiemersmaDitherMethod</code>, <span class="arg">tree_depth</span>=0,
<span class="arg">measure_error</span>=<code>false</code>) ->
<em>image</em>
</p>
</div>
<div class="desc">
<h4>Description</h4>
<p class="imquote">
Analyzes the colors within a reference image and chooses a fixed number of colors to represent the image. The goal of the algorithm is to minimize the
difference between the input and output image while minimizing the processing time.
</p>
<h4>Arguments</h4>
<dl>
<dt>number_colors</dt>
<dd>
The maximum number of colors in the result image. Must be <=
<a href="constants.html#Miscellaneous_constants">QuantumRange</a>.
</dd>
<dt>colorspace</dt>
<dd class="imquote">
The <a href="constants.html#ColorspaceType">colorspace</a> to quantize in. Color reduction, by default, takes place in the RGB color space.
Empirical evidence suggests that distances in color spaces such as YUV or YIQ correspond to perceptual color differences
more closely than do distances in RGB space. The Transparent color space behaves uniquely in that it preserves the matte channel of the image if
it exists.
</dd>
<dt>dither</dt>
<dd>
A <a href="constants.html#DitherMethod">DitherMethod</a> value. Set to <code>NoDitherMethod</code> to disable dithering. See the documentation for the
<a href="https://imagemagick.org/script/command-line-options.php#dither"> ImageMagick -dither option</a>
for more information.
</dd>
<dt>tree_depth</dt>
<dd>
<span class="imquote"
>The tree depth to use while quantizing. The values 0 and 1 support automatic tree depth determination. The tree depth may be forced via values
ranging from 2 to 8. The ideal tree depth depends on the characteristics of the input image, and may be determined through experimentation.</span
>
See the documentation for the
<a href="https://imagemagick.org/script/command-line-options.php#treedepth"> ImageMagick -treedepth option</a>
for more information.
</dd>
<dt>measure_error</dt>
<dd class="imquote">Set to <code>true</code> to calculate quantization errors when quantizing the image.</dd>
</dl>
<h4>Returns</h4>
<p>A new image</p>
<h4>Example</h4>
<p>See the example for <a href="image1.html#colorize">colorize</a>.</p>
<h4>See also</h4>
<p>
<a href="image2.html#ordered_dither">ordered_dither</a>, <a href="image3.html#posterize">posterize</a>,
<a href="ilist.html#quantize">ImageList#quantize</a>
</p>
<h4>Magick API</h4>
<p>QuantizeImage</p>
</div>
<div class="sig">
<h3 id="quantum_operator">quantum_operator</h3>
<p>
<span class="arg">img</span>.quantum_operator(<span class="arg">operator</span>, <span class="arg">rvalue</span>,
<span class="arg">channel</span>=AllChannels) -> <em>self</em>
</p>
</div>
<div class="desc">
<h4>Description</h4>
<p>
Performs the requested integer arithmetic operation on the selected channel of the image. This method allows simple arithmetic operations on the
component values of all pixels in an image. Of course, you could also do this in Ruby using
<a href="image2.html#get_pixels">get_pixels</a> and <a href="#store_pixels">store_pixels</a>, or <a href="#view">view</a>, but
<code>quantum_operator</code> will be faster, especially for large numbers of pixels, since it does not need to convert the pixels from C to Ruby.
</p>
<h4>Arguments</h4>
<dl>
<dt>operator</dt>
<dd>
One of the following <code>QuantumExpressionOperator</code>
constants:
<ul id="quantum_op_list">
<li>AddQuantumOperator</li>
<li><code>AndQuantumOperator</code></li>
<li><code>DivideQuantumOperator</code></li>
<li><code>LShiftQuantumOperator</code></li>
<li><code>MaxQuantumOperator</code></li>
<li><code>MinQuantumOperator</code></li>
<li><code>MultiplyQuantumOperator</code></li>
<li><code>OrQuantumOperator</code></li>
<li><code>RShiftQuantumOperator</code></li>
<li><code>SubtractQuantumOperator</code></li>
<li><code>XorQuantumOperator</code></li>
<li><code>PowQuantumOperator</code></li>
<li><code>LogQuantumOperator</code></li>
<li><code>ThresholdQuantumOperator</code></li>
<li><code>ThresholdBlackQuantumOperator</code></li>
<li><code>ThresholdWhiteQuantumOperator</code></li>
<li><code>GaussianNoiseQuantumOperator</code></li>
<li><code>ImpulseNoiseQuantumOperator</code></li>
<li><code>LaplacianNoiseQuantumOperator</code></li>
<li><code>MultiplicativeNoiseQuantumOperator</code></li>
<li><code>PoissonNoiseQuantumOperator</code></li>
<li><code>UniformNoiseQuantumOperator</code></li>
<li><code>CosineQuantumOperator</code></li>
<li><code>SineQuantumOperator</code></li>
<li><code>AddModulusQuantumOperator</code></li>
</ul>
Some of these constants are not defined in older releases of ImageMagick. To see which ones are defined, enter this statement in IRB:
<pre class="language-ruby">Magick::QuantumExpressionOperator.values {|v| puts v}</pre>
</dd>
<dt>rvalue</dt>
<dd>a <code>Numeric</code> operation rvalue.</dd>
<dt>channel</dt>
<dd>A <a href="constants.html#ChannelType">ChannelType</a> value. The default is to operate on the R, G, and B channels.</dd>
</dl>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<p>Divide the red component of all the pixels in the image by 2:</p>
<pre class="language-ruby">img.quantum_operator(Magick::DivideQuantumOperator, 2, Magick::RedChannel)</pre>
<h4>See also</h4>
<p><a href="image2.html#function_channel">function_channel</a></p>
<p>
The <a href="struct.html#view">Image::View</a> class supports operations on individual pixels and collections of pixels, as well as operations on
channels within pixels. See <a href="#view">view</a>, below.
</p>
<h4>Magick API</h4>
<p>EvaluateImageChannel</p>
</div>
<div class="sig">
<h3 id="radial_blur">radial_blur</h3>
<p><span class="arg">img</span>.radial_blur(<span class="arg">float</span>) -> <em>image</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p class="imquote">Applies a radial blur to the image.</p>
<h4>Arguments</h4>
<dl>
<dt>angle</dt>
<dd>Amount of blur, in degrees</dd>
</dl>
<h4>Returns</h4>
<p>A new image</p>
<h4>Example</h4>
<p class="rollover">
<a href="javascript:popup('radial_blur.rb.html')"
><img
src="ex/radial_blur.jpg"
onmouseover="this.src = 'ex/images/Flower_Hat.jpg'"
onmouseout="this.src = 'ex/radial_blur.jpg'"
alt="radial_blur example"
title="Click to see the example script"
/></a>
<img src="ex/images/spin.gif" alt="" class="spin" title="Mouse over the example to see the original image" />
</p>
<h4>See also</h4>
<p>
<a href="image1.html#blur_image">blur_image</a>, <a href="image2.html#gaussian_blur">gaussian_blur</a>,
<a href="image2.html#motion_blur">motion_blur</a>, <a href="#radial_blur_channel">radial_blur_channel</a>,
<a href="#selective_blur_channel">selective_blur_channel</a>
</p>
<h4>Magick API</h4>
<p>RadialBlurImage</p>
</div>
<div class="sig">
<h3 id="radial_blur_channel">radial_blur_channel</h3>
<p><span class="arg">img</span>.radial_blur_channel(<span class="arg">float</span> [, <span class="arg">channel</span>...]) -> <em>image</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Applies a radial blur to the selected image channels.</p>
<h4>Arguments</h4>
<dl>
<dt>angle</dt>
<dd>Amount of blur, in degrees</dd>
<dt>channel...</dt>
<dd>
0 or more
<a href="constants.html#ChannelType">ChannelType</a> arguments. If no channels are specified, all the channels are blurred.
</dd>
</dl>
<h4>Returns</h4>
<p>A new image</p>
<h4>See also</h4>
<p><a href="#radial_blur">radial_blur</a></p>
<h4>Magick API</h4>
<p>RadialBlurImageChannel</p>
</div>
<div class="sig">
<h3 id="raise">raise</h3>
<p>
<span class="arg">img</span>.raise(<span class="arg">width</span>=6, <span class="arg">height</span>=6,
<span class="arg">raised</span>=<code>true</code>) -> <em>image</em>
</p>
</div>
<div class="desc">
<h4>Description</h4>
<p class="imquote">Creates a simulated three-dimensional button-like effect by lightening and darkening the edges of the image.</p>
<h4>Arguments</h4>
<dl>
<dt>width</dt>
<dd>The width of the raised edge in pixels. The default is 6.</dd>
<dt>height</dt>
<dd>The height of the raised edge in pixels. The default is 6.</dd>
<dt>raised</dt>