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<h6 id="header">RMagick User's Guide and Reference</h6>
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<h1>class ImageList <span class="superclass"><
Array</span><br />
<span class="mixin">mixes in Comparable</span></h1>
<div id="toc">
<h2>Table of Contents</h2>
<h3>class methods</h3>
<ul>
<li><a href="#new">new</a></li>
</ul>
<h3>attributes</h3>
<ul>
<li><a href="#delay_eq">delay=</a></li>
<li><a href="#iterations_eq">iterations=</a></li>
<li><a href="#length">length</a></li>
<li><a href="#scene">scene, scene=</a></li>
<li><a href="#ticks_per_second_eq">ticks_per_second=</a></li>
</ul>
<h3>instance methods</h3>
<div class="toccol">
<ul>
<li><a href="#array_methods">Array methods</a></li>
<li><a href="#spaceship"><=></a></li>
<li><a href="#animate">animate</a></li>
<li><a href="#append">append</a></li>
<li><a href="#average">average</a></li>
<li><a href="#clone">clone</a></li>
<li><a href="#coalesce">coalesce</a></li>
<li><a href="#copy">copy</a></li>
<li><a href="#cur_image">cur_image</a></li>
</ul>
</div>
<div class="toccol">
<ul>
<li><a href="#deconstruct">deconstruct</a></li>
<li><a href="#dup">dup</a></li>
<li><a href="#display">display</a></li>
<li><a href="#flatten_images">flatten_images</a></li>
<li><a href="#from_blob">from_blob</a></li>
<li><a href="#inspect">inspect</a></li>
<li><a href="#map">map</a></li>
<li><a href="#montage">montage</a></li>
</ul>
</div>
<div class="toccol">
<ul>
<li><a href="#morph">morph</a></li>
<li><a href="#mosaic">mosaic</a></li>
<li><a href="#new_image">new_image</a></li>
<li><a href="#ping">ping</a></li>
<li><a href="#quantize">quantize</a></li>
<li><a href="#read">read</a></li>
<li><a href="#to_blob">to_blob</a></li>
<li><a href="#write">write</a></li>
</ul>
</div>
</div>
<h2 class="methods">class methods</h2>
<div class="sig">
<h3 id="new">new</h3>
<p>Magick::ImageList.new -> <em>imagelist</em><br />
Magick::ImageList.new(<span class="arg">filename[,
filename...]]</span>) -> <em>imagelist</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Creates a new imagelist. If one or more image filenames are
specified, opens and reads the files, adding a new image for
each image in the image file(s). Sets the scene number to the
index of the last image, or <code>nil</code> if no filenames
are specified.</p>
<h4>Arguments</h4>
<p>Zero or more image file names.</p>
<h4>Returns</h4>
<p>A new imagelist. The imagelist contains an Image object for
each image in the specified files. A file can contain more than
one image. For example, new will create an image for each frame
in an animated GIF or each layer in a multi-layer Photoshop
file.</p>
<h4>Example</h4>
<pre>
i = Magick::ImageList.new
i = Magick::ImageList.new("Button_A.gif", "Cheetah.jpg")
</pre>
</div>
<h2 class="methods">attributes</h2>
<div class="sig">
<h3 id="delay_eq">delay=</h3>
<p><span class="arg">imagelist.</span>delay=<em>n</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>In conjunction with <a href=
"#ticks_per_second_eq">ticks_per_second</a> sets the length of
time between each image in an animation. The
<code>delay=</code> attribute assigns the same delay to all the
images in the imagelist. Use <a href=
"imageattrs.html#Image.delay">Image#delay=</a> to set different
delay values on individual images.</p>
<h4>Arguments</h4>
<p>An integer value representing the number of ticks that must
elapse between each image in an animation.</p>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<pre>
imagelist.delay = 20 # delay 1/5 of a second between images.
</pre>
<h4>See also</h4>
<p><a href="imageattrs.html#Image.delay">Image#delay=</a></p>
</div>
<div class="sig">
<h3 id="iterations_eq">iterations=</h3>
<p><span class="arg">imagelist.</span>iterations=<em>n</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Sets the number of times an animated image should loop.</p>
<p>The <a href="#animate">animate</a> method and the
ImageMagick animate/GraphicsMagick gm utilities do not respect
this number. Both will repeat the animation until you stop
them. Mozilla (and presumably Netscape) do respect the
value..</p>
<h4>Arguments</h4>
<p>The number of iterations.</p>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<pre>
imagelist.iterations = 10
</pre>
</div>
<div class="sig">
<h3 id="length">length</h3>
<p><span class="arg">imagelist.</span>length ->
<em>anInteger</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Returns the number of images in the imagelist.</p>
<h4>Example</h4>
<pre>
i = Magick::ImageList.new("images/Button_A.gif", "images/Button_B.gif")
i.length » 2
</pre>
</div>
<div class="sig">
<h3 id="scene">scene, scene=</h3>
<p><span class="arg">imagelist</span>.scene ->
<em>anInteger</em><br />
<span class="arg">imagelist</span>.scene =
<em>anInteger</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Get/set the current <em>scene number</em>. The scene number
indicates the image to which <a href="image1.html">Image</a>
methods are sent.</p>
<h4>Example</h4>
<pre>
imagelist.scene = 10
imagelist.scene » 10
</pre>
</div>
<div class="sig">
<h3 id="ticks_per_second_eq">ticks_per_second=</h3>
<p><span class="arg">imagelist</span>.ticks_per_second =
<em>anInteger</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Used in conjunction with <a href="#delay_eq">delay</a> to
establish the elapsed time between frames in an animation. By
default the number of ticks per second is 100.</p>
<p>This attribute is available only in ImageMagick 6.2.4 and
later. Prior to this release the number of ticks per second is
fixed at 100.</p>
<h4>Example</h4>
<pre>
imagelist.ticks_per_second = 1000
</pre>
</div>
<h2 class="methods">instance methods</h2>
<div class="sig">
<h3 id="array_methods">Array methods</h3>
<p> </p>
</div>
<div class="desc">
<h4>Description</h4>
<p><code>ImageList</code> is a subclass of <code>Array</code>,
so you can manipulate the images in an imagelist using almost
all of the methods defined in <code>Array</code>. Typically
these methods also update the scene number. The scene number
will never exceed the number of images in the list, and if the
imagelist contains no images the scene number will be
<code>nil</code>.</p>
<p>Array methods defined in the ImageList class that would
normally return an array return an ImageList.</p>
<p>Most array methods keep the current image current. If the
method moves the current image to a new position, the method
updates the scene number to the new index. If the method
deletes the current image, the scene number is set to the last
image in the list. The following table lists the methods that
do not follow these rules.</p>
<table summary="array method affect on scene number" class=
"simple_table">
<caption>
Array method behavior
</caption>
<thead>
<tr>
<th>Array method</th>
<th>scene number will be...</th>
</tr>
</thead>
<tbody>
<tr>
<td><<</td>
<td>set to index the last image in the list</td>
</tr>
<tr>
<td>clear</td>
<td>set to <code>nil</code></td>
</tr>
<tr>
<td>concat</td>
<td>set to index the last image in the list</td>
</tr>
<tr>
<td>push</td>
<td>set to index the last image in the list</td>
</tr>
<tr>
<td>unshift</td>
<td>set to 0</td>
</tr>
</tbody>
</table>
<p>Adding anything other than a image to an imagelist has
undefined results. Most of the time RMagick will raise an
ArgumentError exception.</p>
<p>The <code>assoc</code>, <code>flatten</code>,
<code>flatten!</code>, <code>join</code>, <code>pack</code>,
and <code>rassoc</code> methods are not defined in the
ImageList class.</p>
<h4>Example</h4>
<p>Add noise to a model image. Append the resulting image to
the imagelist in "example". (See: <a href=
"javascript:popup('demo.rb.html')">demo.rb</a>)</p>
<pre>
example = Magick::ImageList.new
model = Magick::ImageList.new "model.miff"
example << model.add_noise Magick::LaplacisanNoise
</pre>
<h4>See also</h4>
<p><a href="#scene">scene</a>, <a href="#scene">scene=</a></p>
</div>
<div class="sig">
<h3 id="spaceship"><=></h3>
<p><span class="arg">imagelist</span> <=> <span class=
"arg">anOtherImageList</span> -> -1, 0, 1</p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Compares two imagelists and returns -1, 0, or 1 if the
receiver is less than, equal to, or greater than the other
imagelist. The comparison between the receiver (a) and the
other (b) is performed this way:</p>
<ol>
<li>For all images <code>n</code>, if the result of
<code>a[n] <=> b[n]</code> is not 0 then that
is the result of a <=> b. Individual images
are compared by comparing their <a href=
"image3.html#signature">signatures</a>.</li>
<li>If <code>a.scene <=> b.scene</code> is
not 0, returns the result</li>
<li>Returns
<code>a.length <=> b.length</code></li>
</ol>
<p><code>ImageList</code> mixes in the <code>Comparable</code>
module.</p>
<h4>See also</h4>
<p><a href="image1.html#spaceship">Image#<=></a>,
<a href="image3.html#signature">signature</a></p>
</div>
<div class="sig">
<h3 id="animate">animate</h3>
<p><span class="arg">imagelist.</span>animate(<span class=
"arg">[delay]</span>) <span class="arg">[ { optional
arguments } ]</span> -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Animate the images to an X Window screen. By default
displays to the local screen. You can specify a different
screen by assigning the name to the <code>server_name</code>
attribute in the optional arguments block.</p>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<pre>
imagelist.animate
imagelist.animate { self.server_name = "other:0.0" }
</pre>
<h4>See also</h4>
<p><a href="#ImageList.display">display</a></p>
<h4>Note</h4>
<p>The animate method is not supported on native MS
Windows.</p>
<h4>Magick API</h4>
<p>AnimateImages</p>
</div>
<div class="sig">
<h3 id="append">append</h3>
<p><span class="arg">imagelist.</span>append(<code>true</code>
or <code>false</code>) -> <em>anImage</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Append all the images in the imagelist, either vertically or
horizontally. If the images are not of the same width, any
narrow images will be expanded to fit using the background
color.</p>
<h4>Arguments</h4>
<p>If <code>true</code>, rectangular images are stacked
top-to-bottom, otherwise left-to-right.</p>
<h4>Returns</h4>
<p>A image composed of all the images in the imagelist.</p>
<h4>Example</h4>
<p>See the <a href="#ImageList.map">map</a> example.</p>
<h4>Magick API</h4>
<p>AppendImages</p>
</div>
<div class="sig">
<h3 id="average">average</h3>
<p><span class="arg">imagelist.</span>average ->
<em>anImage</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Averages all the images together. Each image in the image
must have the same width and height.</p>
<h4>Returns</h4>
<p>A single image representing the average of all the images in
the imagelist.</p>
<h4>Example</h4>
<p class="rollover"><a href=
"javascript:popup('average.rb.html')">
<!-- This img tag displays the original image when the mouse is over -->
<img style="display:none" id="notaveraged" onmouseout=
"this.style.display='none'; averaged.style.display=''; averagedspin.style.display='';"
title="Click to see the example script" src=
"ex/average_before.gif" alt="average example" /><!--
This img tag displays the averaged image when the mouse is not over
--><img style="display:" id=
"averaged" onmouseover=
"this.style.display='none'; notaveraged.style.display=''; averagedspin.style.display='none';"
src="ex/average_after.gif" alt="average example" /></a>
<img src="ex/images/spin.gif" alt="" class="spin" style=
"left:131px; display:" id="averagedspin" title=
"Mouse over the example to see the 3 original images" /></p>
<h4>Magick API</h4>
<p>AverageImages</p>
</div>
<div class="sig">
<h3 id="clone">clone</h3>
<p><span class="arg">imagelist</span>.clone ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Same as <a href="#dup">dup</a>, but the frozen state of the
original is propogated to the copy.</p>
<h4>Returns</h4>
<p>A new imagelist</p>
<h4>See also</h4>
<p><a href="#copy">copy</a></p>
</div>
<div class="sig">
<h3 id="coalesce">coalesce</h3>
<p><span class="arg">imagelist.</span>coalesce ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Merges all the images in the imagelist into a new imagelist.
Each image in the new imagelist is formed by flattening all the
previous images.</p>
<p>The length of time between images in the new image is
specified by the <a href=
"imageattrs.html#Image.delay">delay</a> attribute of the input
image. The position of the image on the merged images is
specified by the <a href="imageattrs.html#Image.page">page</a>
attribute of the input image.</p>
<h4>Returns</h4>
<p>A new imagelist</p>
<h4>Example</h4>
<p>This example is an animated GIF created by coalescing 25
small images in a grid. Mouse over the image to start the
animation.</p>
<p class="rollover"><a href=
"javascript:popup('coalesce.rb.html')"><img onmouseover=
"this.src='ex/coalesce_anim.gif'" onmouseout=
"this.src='ex/coalesce.gif'" src="ex/coalesce.gif" alt=
"coalesce example" title=
"Click the image to see the example script" /></a><img src=
"ex/images/spin.gif" alt="" class="spin" style="left:159px"
title="Mouse over the example to see the animation" /></p>
<h4>See also</h4><a href="#flatten_images">flatten_images</a>
<h4>Magick API</h4>
<p>CoalesceImages</p>
</div>
<div class="sig">
<h3 id="copy">copy</h3>
<p><span class="arg">imagelist.</span>copy ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Creates a deep copy of the imagelist. The new imagelist
contains a copy of all the images in the original
imagelist.</p>
<h4>Returns</h4>
<p>An imagelist</p>
<h4>Example</h4>
<pre>
imagelist2 = imagelist1.copy
</pre>
<h4>See also</h4><a href="image1.html#copy">Image#copy</a>,
<a href="#clone">clone</a>, <a href="#dup">dup</a>
</div>
<div class="sig">
<h3 id="cur_image">cur_image</h3>
<p><span class="arg">imagelist.</span>cur_image ->
<em>anImage</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Retrieves the image indexed by <a href="#scene">scene</a>.
Raises <code>IndexError</code> if there are no images in the
list.</p>
<p>Both the ImageList class and the Image class support the
<code>cur_image</code> method. Of course, in the Image class,
<code>cur_image</code> simply returns <code>self</code>. When a
method accepts either an image or a imagelist as an argument,
it sends the <code>cur_image</code> method to the argument to
get the current image.</p>
<h4>Returns</h4>
<p>An image</p>
</div>
<div class="sig">
<h3 id="deconstruct">deconstruct</h3>
<p><span class="arg">imagelist.</span>deconstruct ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>This method constructs a new imagelist containing images
that include only the changed pixels between each image and its
successor. The resulting imagelist usually produces a much
smaller file.</p>
<p>The <code>desconstruct</code> method starts by copying the
first image in the list to the output imagelist. Then, for each
pair of images, <code>deconstruct</code> computes the smallest
rectangle that encompasses all the changes between the first
and second image and stores just the changed rectangle of the
second image, along with the offset of the rectangle relative
to the boundary of the first image.</p>
<h4>Returns</h4>
<p>A new imagelist</p>
<h4>Magick API</h4>
<p>DeconstructImages</p>
</div>
<div class="sig">
<h3 id="dup">dup</h3>
<p><span class="arg">imagelist</span>.dup ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Makes a <em>shallow</em> copy of the receiver. The image
elements in the new imagelist are references to the image
elements in the original imagelist, not copies.</p>
<h4>See also</h4>
<p><a href="#copy">copy</a>, <a href="#clone">clone</a></p>
</div>
<div class="sig">
<h3 id="display">display</h3>
<p><span class="arg">imagelist.</span>display <span class=
"arg">[ { optional arguments } ]</span> ->
<em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Displays the images in the imagelist to any X Window screen.
By default displays to the local screen. You can specify a
different screen by assigning the name to the
<code>server_name</code> attribute in the optional arguments
block.</p>
<h4>Returns</h4>
<p>self</p>
<h4>See also</h4>
<p><a href="#animate">animate</a>, <a href=
"image1.html#display">Image#display</a></p>
<h4>Magick API</h4>
<p>DisplayImages</p>
</div>
<div class="sig">
<h3 id="flatten_images">flatten_images</h3>
<p><span class="arg">imagelist.</span>flatten_images ->
<em>anImage</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Combines all the images in the imagelist into a single image
by overlaying each successive image onto the preceding images.
If a image has transparent areas, the underlying image will
show through. Use the <a href="imageattrs.html#page">page</a>
attribute to specify the position of each image with respect to
the preceding images.</p>
<p class="imquote">This is useful for combining Photoshop
layers into a single image.</p>
<h4>Returns</h4>
<p>An image</p>
<h4>Example</h4>
<p><a href=
"javascript:popup('flatten_images.rb.html')"><img alt=
"flatten_images example" src="ex/flatten_images.gif" title=
"Click to see the example script" /></a></p>
<h4>See also</h4>
<p><a href="#coalesce">coalesce</a></p>
<h4>Magick API</h4>
<p>FlattenImageList</p>
</div>
<div class="sig">
<h3 id="from_blob">from_blob</h3>
<p><span class=
"arg">imagelist.</span>from_blob(blob<span class="arg">[,
blob...]</span>) <span class="arg">[ { optional arguments
} ]</span> -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Creates images from the blob (<em>B</em>inary <em>L</em>arge
<em>O</em>bjects) arguments and appends the images to the
imagelist.</p>
<h4>Arguments</h4>
<p>A <em>blob</em> can be a string containing an image file
such as a JPEG or GIF. The string can contain a multi-image
file such as an animated GIF or a Photoshop image with multiple
layers. A blob can also be one of the strings produced by
<a href="#to_blob">to_blob</a>. Control how the image(s) are
created by setting additional <a href=
"info.html">Image::Info</a> attributes in the optional block
argument. Useful attributes include <a href=
"info.html#scene">scene</a>, <a href=
"info.html#number_scenes">number_scenes</a>, and <a href=
"info.html#extract">extract</a>.</p>
<h4>Returns</h4>
<p>An image created from the blob argument(s). The
<code>scene</code> attribute is set to the last image in the
imagelist.</p>
<h4>Example</h4>
<pre>
require 'RMagick'
f = File.open('Cheetah.jpg')
blob = f.read
ilist = Magick::ImageList.new
ilist.from_blob(blob)
ilist.display
</pre>
<h4>See also</h4><a href="#to_blob">to_blob</a>, <a href=
"image3.html#to_blob">Image#to_blob</a>, <a href=
"image1.html#from_blob">Image.from_blob</a>
<h4>Magick API</h4>
<p>BlobToImageList</p>
</div>
<div class="sig">
<h3 id="inspect">inspect</h3>
<p><span class="arg">imagelist.</span>inspect ->
<em>aString</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Produces a string that describes the images in the
imagelist.</p>
<h4>Arguments</h4>
<h4>Returns</h4>
<p>The returned string is a concatenation of the strings
returned by <a href="image2.html#inspect">Image#inspect</a> for
all the images in the imagelist.</p>
<h4>Example</h4>
<pre>
i = Magick::ImageList.new("images/Button_A.gif", "images/Button_B.gif")
» [images/Button_A.gif GIF 127x120+0+0 PseudoClass 256c 8-bit 18136b
images/Button_B.gif GIF 127x120+0+0 PseudoClass 256c 8-bit 5157b]
scene=1
</pre>
<h4>See also</h4>
<p><a href="image2.html#inspect">Image#inspect</a></p>
<h4>Magick API</h4>
<p>The description is essentially the same as that provided by
<a href=
"http://www.imagemagick.org/www/api/image.html#describeimage">DescribeImageList</a></p>
</div>
<div class="sig">
<h3 id="map">map</h3>
<p><span class="arg">imagelist.map</span>(<span class=
"arg">reference</span>, <span class="arg">dither</span>) ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Reduces the colors in the imagelist images to the set of
colors in the <span class="arg">reference</span> image.</p>
<h4>Arguments</h4>
<dl>
<dt>reference</dt>
<dd>An image or a imagelist. If an imagelist,
<code>map</code> uses the current image as the reference
image.</dd>
<dt>dither</dt>
<dd>if <code>true</code>, dither the mapped images.</dd>
</dl>
<h4>Returns</h4>
<p>A new imagelist the same length as the receiver.</p>
<h4>Example</h4>
<p>This example demonstrates how to map images into the 216
"Web safe" colors. Mouse over the image to see the images
before mapping.</p>
<p class="rollover"><a href=
"javascript:popup('map.rb.html')"><img src="ex/map_after.jpg"
alt="map example" title="Click to see the example script"
onmouseover="this.src='ex/map_before.jpg'" onmouseout=
"this.src='ex/map_after.jpg'" /></a><img src=
"ex/images/spin.gif" alt="" class="spin" style="left: 525px;"
title="Mouse over the example to see the original image" /></p>
<h4>See also</h4>
<p><a href="image2.html#map">Image#map</a>, <a href=
"#quantize">quantize</a></p>
<h4>Magick API</h4>
<p>MapImages</p>
</div>
<div class="sig">
<h3 id="montage">montage</h3>
<p><span class="arg">imagelist.</span>montage <span class=
"arg">[ { optional arguments } ]</span> ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Creates a composite image by reducing the size of the input
images and arranging them in a grid on the background color or
texture of your choice. There are many configuration options.
For example, you can specify the number of columns and rows,
the distance between images, and include a label with each
small image (called a <em>tile</em>).</p>
<p>All of <code>montage</code>'s configuration options are
specified by assigning values to attributes in a block
associated with the method call.</p>
<p>As you can see in the examples below, when you assign a
value to a montage attribute you must specify <code>self</code>
as the receiver so that Ruby can distinguish the method call
from an assignment to a local variable.</p>
<p>You may assign a <a href="struct.html#Pixel">Pixel</a>
object to any attribute that accepts a color name.</p>
<h4>Montage attributes</h4>
<dl>
<dt>background_color=</dt>
<dd>The composite image background color.</dd>
<dt>border_color=</dt>
<dd>The tile border color.</dd>
<dt>border_width=</dt>
<dd>The tile border width in pixels.</dd>
<dt>compose=</dt>
<dd>The <a href="constants.html#CompositeOperator">composite
operator</a> to use when compositing the tile images onto the
background. The default composition operator is
<code>OverCompositeOp</code>.</dd>
<dd><em>Hint:</em> You can use a different composite operator
for each tile by setting each image's <a href=
"imageattrs.html#Image.compose">compose=</a> attribute to the
desired operator. In the optional arguments block, set
<code>compose</code> to UndefinedCompositeOp.</dd>
<dt>fill=</dt>
<dd>If the tiles have labels, the label fill color. The
default fill color is black.</dd>
<dt>font=</dt>
<dd>If the tiles have labels, the label font. The default
font is Helvetica.</dd>
<dt>frame=</dt>
<dd>
The size of an ornamental frame surrounding each tile. The
frame specification may be either a string or a <a href=
"struct.html#Geometry">Geometry</a> object. If the argument
is a string, it must have the form
<code><width>x<height>+<outer bevel
width>+<inner bevel width></code>. If the argument
is a Geometry object, specify the width and height of the
frame with the <code>width</code> and <code>height</code>
attributes, and specify the outer bevel width and the inner
bevel width with the <code>x</code> and <code>y</code>
attributes. The values are in pixels. For example, to
surround each tile with a frame 20 pixels wide by 20 pixels
high and a 4-pixel inner and outer bevel, use:
<pre>
self.frame = "20x20+4+4"
</pre>or
<pre>
self.frame = Magick::Geometry.new(20,20,4,4)
</pre>
</dd>
<dd>If the tile has a label, the label is included in the
frame. The default is to have no frame.</dd>
<dd>See <a href="image1.html#frame">Image#frame</a>.</dd>
<dt>geometry=</dt>
<dd>
The size of the tiles and the distance between tiles. The
value can be either a <a href=
"imusage.html#geometry">geometry string</a> or a <a href=
"struct.html#Geometry">Geometry</a> object. The geometry
string has the form:
<code><tile-width>x<tile-height>+<distance-between-columns>+<distance-between-rows></code>.
If you use a Geometry object, specify the tile width and
height with the <code>width</code> and <code>height</code>
attributes, and the distance between rows and distance
between columns by the <code>x</code> and <code>y</code>
attributes. To create tiles that are 130 pixels wide and
194 pixels tall, with 10 pixels between each column of
tiles and 5 between each row, use:
<pre>
self.geometry = "130x194+10+5"
</pre>or
<pre>
self.geometry = Magick::Geometry.new(130, 194, 10, 5)
</pre>Both the geometry string and the <code>Geometry</code> object
support flags that specify additional constraints. The default
geometry is "120x120+4+3>".
</dd>
<dt>gravity=</dt>
<dd>The <a href="constants.html#GravityType">direction</a>
used when adding the tile labels. (See <a href=
"draw.html#Draw.annotate">annotate</a>.)</dd>
<dt>matte_color=</dt>
<dd>The matte color. The default is #bdbdbd.</dd>
<dt>pointsize=</dt>
<dd>If the tiles have labels, the size of the label font in
points. The default is 12 points.</dd>
<dt>shadow=</dt>
<dd>If set to <code>true</code>, adds a drop shadow to each
tile. The default is <code>false</code>.</dd>
<dt>stroke=</dt>
<dd>If the tiles have labels, sets the stroke (outline) color
of the label text. The default is "transparent".</dd>
<dt>texture=</dt>
<dd>
A image to be tiled on the background of the composite
image. If present, this attribute overrides the background
color. For example, to use ×Magick's built-in
"granite" texture as the background, use:
<pre>
self.texture = Magick::Image.read("granite:").first
</pre>
<p>The default is no texture.</p>
</dd>
<dt>tile=</dt>
<dd>
The number of columns and rows to use when arranging the
tiles on the composite image. The value can be either a
string or a <a href="struct.html#Geometry">Geometry</a>
object. If the value is a string, it should have the form
<code>"<columns>x<rows>"</code>. If the value
is a Geometry object, specify the number of columns as the
<code>width</code> attribute and the number of rows as the
<code>height</code> attribute. <code>montage</code> always
generates all the rows, leaving empty cells if necessary.
To arrange the tiles 4 across and 10 down, use:
<pre>
self.tile = "4x10"
</pre>or
<pre>
self.tile = Magick::Geometry.new(4,10)
</pre>
<p>The default is "6x4". If there are too many tiles to fit
on one composite image, <code>montage</code> creates
multiple composite images.</p>
</dd>
</dl>
<h4>Tile labels</h4>
<p>To add labels to the tiles, assign a "Label" property to
each image. The <code>montage</code> method will use the value
of the property as the label. For example,</p>
<pre>
img[2]['Label'] = "Mom's Birthday"
</pre>
<p>See <a href="image1.html#aset">[]=</a>.</p>
<h4>Returns</h4>
<p>An imagelist that contains as many images as are required to
display all the tiles.</p>
<h4>Example</h4><a href=
"javascript:popup('demo.rb.html')">demo.rb</a>
<h4>Magick API</h4>
<p>MontageImages</p>
</div>
<div class="sig">
<h3 id="morph">morph</h3>
<p><span class="arg">imagelist.</span>morph(<span class=
"arg">n</span>) -> <em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Transforms a image into another image by inserting
<code>n</code> in-between images. Requires at least two images.
If more images are present, the 2nd image is transformed into
the 3rd, the 3rd to the 4th, etc.</p>
<h4>Arguments</h4>
<p>The number of in-between images to insert between each pair
of images.</p>
<h4>Returns</h4>
<p>An imagelist containing copies of the original images plus
the in-between images.</p>
<h4>Example</h4>
<p>This animated GIF was created by reading the "0", "1", "2"
and "3" images, then using <code>morph</code> to create 8
images between each original image. Mouse over the image to
start the animation.</p>
<p class="rollover"><a href=
"javascript:popup('morph.rb.html')"><img onmouseover=
"this.src='ex/morph.gif'" onmouseout=
"this.src='ex/images/Button_0.gif'" src=
"ex/images/Button_0.gif" alt="morph example" title=
"Click the image to see the example script" /></a><img src=
"ex/images/spin.gif" alt="" class="spin" style="left:131px"
title="Mouse over the example to see the animation" /></p>
<h4>Magick API</h4>
<p>MorphImages</p>
</div>
<div class="sig">
<h3 id="mosaic">mosaic</h3>
<p><span class="arg">imagelist.</span>mosaic ->
<em>anImage</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Composites all the images into a single new image. The
location of each image is determined by the value of its
<a href="imageattrs.html#Image.page">page</a> attribute.</p>
<h4>Returns</h4>
<p>An image</p>
<h4>Example</h4>
<p><a href="javascript:popup('mosaic.rb.html')"><img src=
"ex/mosaic.gif" alt="mosaic example" title=
"Click to see the example script" /></a></p>
<h4>See also</h4><a href="#coalesce">coalesce</a>, <a href=
"#flatten_images">flatten_images</a>, <a href=
"#montage">montage</a>
<h4>Magick API</h4>
<p>MosaicImages</p>
</div>
<div class="sig">
<h3 id="new_image">new_image</h3>
<p><span class="arg">imagelist.</span>new_image(<span class=
"arg">columns</span>, <span class="arg">rows</span><span class=
"arg">[, fill]</span>) <span class="arg">[ { optional
arguments } ]</span> -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Adds a new image to the imagelist. The image can have an
optional <a href="struct.html#fill">fill</a> applied to it.</p>
<h4>Arguments</h4>
<p>Creates a new image with the specified number of rows and
columns. If the optional <code>fill</code> argument is used,
calls the <code>fill</code> method to fill the image.
Otherwise, the image is filled with the background color.</p>
<p>You can set any <a href="info.html">Image::Info</a>
attributes in an associated block. These attributes supply
options to be used when creating the image. For example, you
can specify the <a href=
"imageattrs.html#background_color">background color</a> to fill
the image with (see the example), the <a href=
"imageattrs.html#depth">depth</a>, <a href=
"imageattrs.html#border_color">border color</a>, etc.</p>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<p>Create a square red image.</p>
<pre>
imagelist = Magick::ImageList.new
imagelist.new_image(100, 100) { self.background_color = "red" }
</pre>
</div>
<div class="sig">
<h3 id="ping">ping</h3>
<p><span class="arg">imagelist.</span>ping(<span class=
"arg">filename</span>[, <span class="arg">filename</span>...])
-> <em>self</em><br />
<span class="arg">imagelist.</span>ping(<span class=
"arg">file</span>[, <span class="arg">file</span>...]) ->
<em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Reads the image files and creates one or more images that
contain all the image attributes but without the pixel data. If
all you need is the image attributes, the <code>ping</code>
method is much faster and consumes less memory than <a href=
"#read"><code>read</code></a>.</p>
<h4>Arguments</h4>
<p>One or more image file names or open file objects.</p>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<pre>
imagelist = Magick::ImageList.new
imagelist.ping "Button_A.gif"
puts "The image has #{i.columns} columns and #{i.rows} rows." »
The image has 127 columns and 120 rows.
</pre>
<h4>See also</h4><a href="#read">read</a>
<h4>Magick API</h4>
<p>PingImage</p>
</div>
<div class="sig">
<h3 id="quantize">quantize</h3>
<p><span class="arg">imagelist.</span>quantize(nc=256,
colorspace=<code>Magick::RGBColorspace</code>,
dither=<code>true</code>, tree_depth=0,
measure_error=<code>false</code>) ->
<em>anImageList</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p class="imquote">Analyzes the colors within a set of
reference images and chooses a fixed number of colors to
represent the set. The goal of the algorithm is to minimize the
difference between the input and output images while minimizing
the processing time.</p>
<h4>Arguments</h4>
<dl>
<dt>nc</dt>
<dd>The maximum number of colors to use in the output images.
Must be less than or equal to <a href=
"constants.html#Miscellaneous_constants">MaxRGB</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 class="imquote">Apply Floyd/Steinberg error diffusion to
the image. When the size of the color palette is less than
the image colors, this trades off spacial resolution for
color resolution by dithering to achieve a similar looking
image.</dd>
<dt>tree_depth</dt>
<dd class="imquote">Specify 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 two to eight. The ideal tree depth depends on
the characteristics of the input image, and may be determined
through experimentation.</dd>
<dt>measure_error</dt>
<dd><span class="imquote">Calculate quantization errors when
quantizing the image.</span> Stores the results for each
image in the imagelist <a href=
"imageattrs.html#Image.mean_error_per_pixel">mean_error_per_pixel</a>,
<a href=
"imageattrs.html#Image.normalized_maximum_error">normalized_maximum_error</a>,
and <a href=
"imageattrs.html#Image.normalized_mean_error">normalized_mean_error</a>
attributes. Stores the number of colors used for the image in
the <a href=
"imageattrs.html#Image.total_colors">total_colors</a>
attribute.</dd>
</dl>
<h4>Returns</h4>
<p>A new imagelist containing quantized copies of the images in
the original image.</p>
<h4>Example</h4>
<p>This example shows the effect of quantizing 3 images to a
set of 16 colors in the RGB colorspace. Mouse over the image to
see the images before quantizing.</p>
<p class="rollover"><a href=
"javascript:popup('quantize-m.rb.html')"><img src=
"ex/quantize-m_after.jpg" alt="quantize example" title=
"Click to see the example script" onmouseover=
"this.src='ex/quantize-m_before.jpg'" onmouseout=
"this.src='ex/quantize-m_after.jpg'" /></a> <img src=
"ex/images/spin.gif" alt="" class="spin" style="left: 505px;"
title="Mouse over the example to see the original image" /></p>
<h4>See also</h4>
<p><a href="image3.html#quantize">Image#quantize</a></p>
<h4>Magick API</h4>
<p>QuantizeImages</p>
</div>
<div class="sig">
<h3 id="read">read</h3>
<p><span class="arg">imagelist.</span>read(<span class=
"arg">filename[, filename...]</span>) <span class=
"arg">[ { optional arguments } ]</span> ->
<em>self</em><br />
<span class="arg">imagelist.</span>read(<span class=
"arg">file[, file...]</span>) <span class="arg">[ {
optional arguments } ]</span> -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Reads one or more image files and adds the images to the
imagelist. After reading all the files, sets the <a href=
"#scene">scene</a> number to the last image in the list.</p>
<p>The image files may be multi-frame (animated or layered)
files. In this case <code>read</code> adds multiple images per
file to the imagelist.</p>
<h4>Arguments</h4>
<p>One or more filenames or open file objects. You can also
specify optional arguments to be used when reading the file(s)
by setting <a href="info.html">Image::Info</a> attributes in
the optional block.</p>
<h4>Returns</h4>
<p>self</p>
<h4>Example</h4>
<pre>
i = Magick::ImageList.new
number = '0'
4.times do
i.read "images/Button_" + number + ".gif"
number.succ!
end
</pre>
<p>Also see the <a href="#morph">morph</a> example and <a href=
"javascript:popup('demo.rb.html')">demo.rb</a>.</p>
<h4>See also</h4>
<p><a href="image3.html#read">Image.read</a></p>
<h4>Magick API</h4>
<p>ReadImage</p>
<h4>Notes</h4>
<p>You can create images using ×Magick's built-in formats
with the <code>read</code> method. See <a href=
"imusage.html#builtin_formats">Built-in image formats</a>.</p>
</div>
<div class="sig">
<h3 id="to_blob">to_blob</h3>
<p><span class="arg">imagelist.</span>to_blob <span class=
"arg">[ { optional arguments } ]</span> ->
<em>aString</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Converts the images in the imagelist to a <em>blob</em>.
<span class="imquote">A blob contains data that directly
represent a particular image format in memory instead of on
disk.</span></p>
<p>Control the format of the blob by setting <a href=
"info.html">Image::Info</a> attributes in an associated
block.</p>
<h4>Returns</h4>
<p>The blob in the form of a string</p>
<h4>Example</h4>
<pre>
i = Magick::ImageList.new "birthday.png"
s = i.to_blob » a string representing the image.
</pre>
<h4>See also</h4>
<p><a href="#from_blob">from_blob</a>, <a href=
"image3.html#to_blob">Image#to_blob</a>, <a href=
"image1.html#from_blob">Image.from_blob</a></p>
<h4>Magick API</h4>
<p>ImageListToBlob</p>
</div>
<div class="sig">
<h3 id="write">write</h3>
<p><span class="arg">imagelist.</span>write(<span class=
"arg">filename</span>) <span class="arg">[ { optional
arguments } ]</span> -> <em>self</em><br />
<span class="arg">imagelist.</span>write(<span class=
"arg">file</span>) <span class="arg">[ { optional
arguments } ]</span> -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>If the image format <a href="imusage.html#formats">indicated
by the filename</a> supports multiple images per file (animated
images), <code>write</code> writes all the images in the
imagelist to a single file. Otherwise, <code>write</code>
writes each image to a separate file.</p>
<p>Regardless of the original format, <code>write</code>
converts the images to the format specified by the
filename.</p>
<p>If the imagelist contains more than one image and the output
format does not support multi-frame images, each image is
written to a file that has the filename you specify followed by
a period (.) and the scene number. You can change this behavior
by embedding a %d, %0Nd, %o, %0No, %x, or %0Nx printf format
specification in the file name.</p>
<h4>Arguments</h4>
<p>A filename or open file object. Indicate the desired image
<a href="imusage.html#formats">format</a> either by the suffix
(i.e. <code>.jpg</code>, <code>.png</code>) or the prefix
(<code>ps:</code>) to the filename. If the argument is an open
file object, you can specify a format for each image in the
list by setting its <a href="imageattrs.html#format">format</a>
attribute.</p>
<p>You can also specify optional arguments by setting <a href=
"info.html">Image::Info</a> attributes in an associated
block.</p>
<h4>Returns</h4>
<p>self, or <code>nil</code> if the format cannot be
determined.</p>
<h4>Example</h4>
<pre>
# The PNG format does not support multi-frame files,
# so each image is written to a separate file.
i = Magick::ImageList.new "animated.gif"
p i.length » 3 # contains 3 images
i.write "test.png" » test.png.0
» test.png.1
» test.png.2
# ×Magick's MIFF format does support multi-frame
# files, so all 3 images are written to one file.
i.write "animated.miff" » animated.miff
</pre>
<h4>See also</h4>
<p><a href="image3.html#write">Image#write</a></p>
<h4>Magick API</h4>
<p>WriteImages</p>
</div>
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