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<p id="magick">Ruby+ImageMagick<span class="tm">TM</span><br />
Version 0.0.0</p>
<h1>User's Guide and Reference</h1>
<h2>Table of Contents</h2>
<div id="toc">
<li><a href="#introduction">Introduction</a></li>
<li>User's Guide</li>
<li style="list-style: none">
<li><a href="usage.html">How to Use RMagick</a></li>
<li><a href="imusage.html">ImageMagick
<li><a href="optequiv.html">Magick Command Options and
Their Equivalent Methods</a></li>
<li><a href="comtasks.html">Common Tasks</a></li>
<li style="list-style: none">
<li style="list-style: none">
<li><a href="magick.html">Magick</a></li>
<li style="list-style: none">
<li><a href="ilist.html">ImageList</a></li>
<li><a href="imageattrs.html">Image (attribute
<li><a href="image1.html">Image (class and instance
methods, part 1)</a></li>
<li><a href="image2.html">Image (instance methods,
part 2)</a></li>
<li><a href="image3.html">Image (instance methods,
part 3)</a></li>
<li><a href="draw.html">Draw</a></li>
<a href="struct.html">Miscellaneous classes</a>
<li><a href="struct.html#view">Image::View</a></li>
<li><a href="struct.html#Geometry">Geometry</a></li>
<li><a href="struct.html#Pixel">Pixel</a></li>
<li><a href="struct.html#struct">Struct
<li><a href="struct.html#fill">Fill classes</a></li>
<li><a href="struct.html#exception">Exception
<li><a href="info.html">Image::Info - Optional method
<li><a href="constants.html">Constants</a></li>
<li>RVG - Ruby Vector Graphics</li>
<li style="list-style:none">
<li><a href="rvgtut.html">Drawing with RVG: A
<li>RVG Reference
<li><a href="rvg.html">class RVG</a></li>
<li><a href="rvggroup.html">class RVG::Group</a></li>
<li><a href="rvgimage.html">class RVG::Image</a></li>
<li><a href="rvgpattern.html">class
<li><a href="rvgclip.html">class
<li><a href="rvgtext.html">class RVG::Text</a></li>
<li><a href="rvgtspan.html">class RVG::Tspan</a></li>
<li><a href="rvguse.html">class RVG::Use</a></li>
<li><a href="rvgstyle.html">The styles
<li><a href="rvgshape.html">The shapes
<li><a href="rvgxform.html">The transform
<h2 id="introduction">Introduction</h2>
<h3>What is RMagick?</h3>
<p>RMagick is a binding from Ruby to the ImageMagick <span class=
"tm">TM</span> image manipulation library. Here's how the
<a href="">ImageMagick home
page</a> describes ImageMagick:</p>
<div class="imquote">
<p>ImageMagick<span style=
"font-size: x-small; vertical-align: super">TM</span>... is a
free software suite to create, edit, and compose bitmap images.
It can read, convert and write images in a large variety of
formats. Images can be cropped, colors can be changed, various
effects can be applied, images can be rotated and combined, and
text, lines, polygons, ellipses and B&eacute;zier curves can be
added to images and stretched and rotated.</p>
<p>ImageMagick offers a full range of image processing tools that
provide the capability to:</p>
<div class="imquote">
<li>Convert an image from one format to another (e.g. TIFF to
<li>Resize, rotate, sharpen, color reduce, or add special
effects to an image</li>
<li>Create a montage of image thumbnails</li>
<li>Create a transparent image suitable for use on the
<li>Turn a group of images into a GIF animation sequence</li>
<li>Create a composite image by combining several separate
<li>Draw shapes or text on an image</li>
<li>Decorate an image with a border or frame</li>
<li>Describe the format and characteristics of an image</li>
<p>RMagick is a complete interface to ImageMagick. Version 1.0.0
was released in February, 2003. Within its four major classes and
30 minor classes RMagick defines over 600 methods and 225
constants. RMagick exploits Ruby idioms such as blocks and
iterators, Struct classes, symbols, ?- and !-suffixed methods,
and exceptions.</p>
<h3>About this document</h3>
<p>This document describes Version 0.0.0 of RMagick. It is
divided into 4 parts. The first is this page. The second part is
a user's guide covering both RMagick and ImageMagick usage and
conventions. The third part is a reference guide to the
ImageList, Image, and Draw classes. This guide includes many
<p>The fourth part covers Ruby Vector Graphics (RVG). RVG is a
facade for Draw that provides a high-level API for scalable
vector graphics. The RVG section includes a tutorial and complete
reference documentation.</p>
<p>Accompanying the HTML documentation is a set of over 175
example RMagick programs. Each is a complete, stand-alone program
that either creates an image from scratch or modifies an input
image using one or more RMagick methods. The output images are
used as illustrations in the HTML documentation. Throughout this
document, click any example image to see the program that created
<p><b>Names&nbsp;&nbsp;</b>I've tried to follow existing Ruby
conventions in this document. A class is identified by its name,
which always starts with a capital letter. An object is referred
to by its class name, starting with a small letter. For example,
a generic ImageList object is referred to as an
<em>imagelist</em>. In the Reference section, when a method
signature identifies the type of an argument or return value, the
type is shown by preceding the class name by "a" or "an". For
example, <code>anImage</code> refers to an Image object, and
<code>anImageList</code> refers to an ImageList object. Class
methods are identified like this: <code>Class.method</code>.
Instance methods are identified like this:
<p>RMagick is implemented in the <b>Magick</b> module, therefore
its constants are in the Magick namespace. However, for clarity
I've omitted the <code>Magick::</code> prefix in most places in
this document. You can use the <code>include Magick</code>
statement to add the constants and methods to the Object
<p><b>ImageMagick documentation&nbsp;&nbsp;</b><span class=
"imquote">Text that looks like this</span> is quoted from the
ImageMagick documentation.</p>
<p><b>Example programs and images&nbsp;&nbsp;</b> All of the
example images on these pages were created by RMagick. Click the
image to see the progam code. (You may need to configure your
browser to allow JavaScript and popup windows.) All example
images show the result of applying the method. Many example
images show the "before" image as well. When the image is
accompanied by this symbol <img style="display:inline" src=
"ex/images/spin.gif" alt="rollover" /> mouse over the image to
see the "before" version.</p>
<h3>How to get help</h3>
<p>If you have a question that is not answered by these pages,
you can post it at the <a href=
"">Support Request
Tracker</a> or the <a href=
"">Feature Request
Tracker</a> on RubyForge, or email me at <code>rmagick at</code>.</p>
<h3><a name="bugs" id="bugs">Reporting bugs</a></h3>
<p>Please report problems with RMagick installation and usage to
the <a href="">Bug
Tracker</a> at RubyForge, or email me at <code>rmagick at</code>.</p>
<p>For quickest results, include the RMagick, ImageMagick and
Ruby version numbers, along with a thorough description of the
problem. RMagick will tell you both its version number and
ImageMagick's version number. Simply bring up irb and run this
command: <code>ruby -r RMagick -e "puts
<pre class="example" id="version">
This is RMagick 1.15.0 ($Date: 2007/01/26 23:41:21 $) Copyright (C) 2007 by Timothy P. Hunter
Built with ImageMagick 6.3.1 01/13/07 Q16
Built for ruby 1.8.5 (2006-08-25) [i686-linux]
Web page:
<p>It will help a lot if you supply a small Ruby program that
reproduces the problem. (Don't forget to include any input image
<p>Please remember I can't help with Ruby or ImageMagick
installation and configuration problems. For help with Ruby, post
your questions to <code>comp.lang.ruby</code>. For help with
ImageMagick, join the ImageMagick mailing list. See the
instructions at <a href=
<p>I'm not an image processing guru, either, so I probably won't
be able to help with questions about specific image formats and
transformations. I will be glad, however, to intermediate between
RMagick users and the ImageMagick developers.</p>
<p>If you have a script or an image using RMagick that you're
particularly proud of, let me know. I'd like to collect your
contributions, along with other users' contributions, and put
them in a <code>contrib</code> directory to distribute with
RMagick. I'm particularly interested in getting examples for the
RMagick methods that currently have no examples.</p>
<h3><a name="copyrights" id="copyrights">Copyright
<li>RMagick &copy; 2002-2007 Timothy P. Hunter.</li>
<li>ImageMagick &copy; 1999-2007 ImageMagick Studio.</li>
<li>Ruby is copyrighted free software by Yukihiro
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