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    <h6 id="header">RMagick 6.1.1 User's Guide and Reference</h6>

    <div class="nav">&laquo;&nbsp;<a href="comtasks.html">Prev</a> | <a href="index.html">Contents</a> | <a href="ilist.html">Next</a>&nbsp;&raquo;</div>

    <h1>module Magick</h1>

    <div id="toc">
      <h2>Table of Contents</h2>

      <h3>module methods</h3>

      <ul>
        <li><a href="#colors">colors</a></li>

        <li><a href="#fonts">fonts</a></li>

        <li><a href="#formats">formats</a></li>

        <li><a href="#limit_resource">limit_resource</a></li>

        <li><a href="#set_cache_threshold">set_cache_threshold</a></li>

        <li><a href="#set_log_event_mask">set_log_event_mask</a></li>

        <li><a href="#set_log_format">set_log_format</a></li>
      </ul>
    </div>

    <h2 class="methods">module methods</h2>

    <div class="sig">
      <h3 id="colors">colors</h3>

      <p>
        Magick.colors <span class="arg">{ |color| block }</span> -&gt; <em>Magick</em><br />
        Magick.colors -&gt; <em>array</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Lists the <a href="imusage.html#color_names">named colors</a>. If the optional block is present, calls the block once for each color, passing a
        Magick::Color object. Otherwise, returns an array of Magick::Color objects, one for each color.
      </p>

      <p>The Magick::Color class is a Struct class with the following attributes:</p>

      <table class="simple_table" summary="magic color attributes">
        <caption>
          Magick::Color attributes
        </caption>

        <tr>
          <th>Attribute</th>

          <th>Value</th>
        </tr>

        <tr>
          <td>name</td>

          <td>The color name. For example, "red".</td>
        </tr>

        <tr>
          <td>compliance</td>

          <td>A <a href="constants.html#ComplianceType">ComplianceType</a> value such as X11Compliance.</td>
        </tr>

        <tr>
          <td>color</td>

          <td>A <a href="struct.html#Pixel">Pixel</a> object containing the RGB values.</td>
        </tr>
      </table>

      <h4>Returns</h4>

      <p>If no block is associated with the call, returns an array of Magick::Color objects.</p>

      <h4>Example</h4>

      <p>This is a small sample of <code>colors.miff</code>, the complete image created by the example program.</p>

      <p>
        <a href="javascript:popup('colors.rb.html')"><img src="ex/colors.gif" title="Click to see the example script" alt="Magick::colors example" /></a>
      </p>

      <h4>Magick API</h4>

      <p>GetColorInfo</p>
    </div>

    <div class="sig">
      <h3 id="fonts">fonts</h3>

      <p>
        Magick.fonts <span class="arg">{ |font| block }</span> -&gt; <em>Magick</em><br />
        Magick.fonts -&gt; <em>array</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Lists the fonts that ImageMagick knows about. If the optional block is present, calls the block once for each font, passing a Magick::Font object.
        Otherwise, returns an array of Magick::Font objects, one for each font.
      </p>

      <p>The Magick::Font class is a Struct class with the following attributes:</p>

      <table summary="font class attributes" class="simple_table">
        <caption>
          Magick::Font attributes
        </caption>

        <tr>
          <th>Attribute</th>

          <th>Value</th>
        </tr>

        <tr>
          <td>name</td>

          <td>The font name. For example, "Palatino-Roman".</td>
        </tr>

        <tr>
          <td>description</td>

          <td>The font description. For example, "Palatino Roman".</td>
        </tr>

        <tr>
          <td>family</td>

          <td>The font family. For example, "Palatino", "Helvetica", or "Courier".</td>
        </tr>

        <tr>
          <td>style</td>

          <td>A <a href="constants.html#StyleType">StyleType</a> value such as <code>NormalStyle</code>.</td>
        </tr>

        <tr>
          <td>stretch</td>

          <td>A <a href="constants.html#StretchType">StretchType</a> value such as <code>NormalStretch</code>.</td>
        </tr>

        <tr>
          <td>weight</td>

          <td>The font weight, one of 100, 200, 300, 400, 500, 600, 700, 800, or 900.</td>
        </tr>

        <tr>
          <td>encoding</td>

          <td>The font encoding, such as "AppleRoman". May be <code>nil</code>.</td>
        </tr>

        <tr>
          <td>foundry</td>

          <td>The font foundry. "URW", for example. May be <code>nil</code>.</td>
        </tr>

        <tr>
          <td>format</td>

          <td>
            If the font is a Type1 font, has the value "type1", otherwise
            <code>nil</code>.
          </td>
        </tr>
      </table>

      <h4>Returns</h4>

      <p>If no block is associated with the call, returns an array of Magick::Font objects.</p>

      <h4>Example</h4>

      <p>
        <a href="javascript:popup('fonts.rb.html')" title="The example script">fonts.rb</a>
      </p>

      <h4>Magick API</h4>

      <p>GetFontInfo</p>
    </div>

    <div class="sig">
      <h3 id="formats">formats</h3>

      <p>
        Magick.formats <span class="arg">{ |f,v| block }</span> -&gt; <em>Magick</em><br />
        Magick.formats -&gt; <em>hash</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Describes the image formats supported by ImageMagick. If the optional block is present, calls the block once for each image format. The first argument,
        <em>f</em>, is the format name. The second argument, <em>v</em>, is the properties string described below.
      </p>

      <h4>Returns</h4>
      A hash of image formats and their properties. Each key in the returned hash is the name of a supported image format. Each value is a string in the form
      "BRWA". The details are in this table:

      <table summary="format string symbols" class="simple_table">
        <caption>
          Format property codes
        </caption>

        <tr>
          <th>Code</th>

          <th>Definition</th>
        </tr>

        <tr>
          <td>B</td>

          <td>is "*" if the format has native blob support, and "-" otherwise.</td>
        </tr>

        <tr>
          <td>R</td>

          <td>is "r" if ImageMagick can read the format, and "-" otherwise.</td>
        </tr>

        <tr>
          <td>W</td>

          <td>is "w" if ImageMagick can write the format, and "-" otherwise.</td>
        </tr>

        <tr>
          <td>A</td>

          <td>is "+" if the format supports multi-image files, and "-" otherwise.</td>
        </tr>
      </table>

      <h4>Example</h4>

      <pre class="language-ruby">
p Magick.formats
#=&gt; {"TIF"=&gt;"*rw+",
#  "H"=&gt;"*rw-",
#  "MNG"=&gt;"*rw+",
#  "NULL"=&gt;"*rw-",
#  ...
#  "G"=&gt;"*rw+",
#  "GIF"=&gt;"*rw+",
#  "PDB"=&gt;"*rw+"}
</pre
      >

      <h4>Magick API</h4>

      <p>GetMagickInfo</p>

      <h4>Note</h4>

      <p>
        ImageMagick depends on external programs for some formats. Depending on how ImageMagick was installed on your system, some formats may not be available.
        If you have questions, ask your system administrator.
      </p>
    </div>

    <div class="sig">
      <h3 id="limit_resource">limit_resource</h3>

      <p>
        Magick.limit_resource(<span class="arg">resource_type</span> [, <span class="arg">limit</span>]) -&gt;
        <span class="arg">old_limit</span>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Sets a limit to the amount of a resource, or gets the current limit for the resource.
        <span class="imquote">When the limit is reached, ImageMagick will fail in some fashion or take compensating actions if possible.</span>
        The default limits vary according to the platform. See the ImageMagick documentation for the <em>-limit</em> option for more information.
      </p>

      <h4>Arguments</h4>
      This method may be called with one or two arguments. The first argument identifies the resource. If specified, the second argument is the limit.

      <dl>
        <dt>resource_type</dt>

        <dd>
          One of the symbols <code>:area</code>, <code>:disk</code>, <code>:file</code>, <code>:map</code>, <code>:memory</code>, or <code>:time</code>. You may
          use a string instead of a symbol.
        </dd>

        <dt>limit</dt>

        <dd>
          If present, the limit for the resource. This argument is always an integer number. If the <span class="arg">resource_type</span> is
          <code>:file</code>, the limit is the number of open files. If <code>:memory</code> or <code>:map</code>, the limit is measured megabytes. If
          <code>:disk</code>, the limit is measured in gigabytes. If the <span class="arg">resource_type</span> is <code>:area</code> the limit is the maximum
          width * height of an image in pixels that can reside in pixel cache memory. If <code>:time</code>, the limit is measured in seconds. If this argument
          is omitted the limit is not changed.
        </dd>
      </dl>

      <h4>Returns</h4>

      <p>The current resource limit. If a new limit is specified this is the limit <em>before</em> the change.</p>

      <h4>Notes</h4>

      <p>This method supersedes <code>set_cache_threshold</code>.</p>

      <p>
        Setting the <code>:time</code> limit resets the elapsed time to zero in the pixel cache. Call it before any operation that you need to set a time limit
        on.
      </p>
    </div>

    <div class="sig">
      <h3 id="set_cache_threshold">set_cache_threshold</h3>

      <p>Magick.set_cache_threshold(<span class="arg">threshold</span>)</p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Set the amount of free memory allocated for the pixel cache. Once this threshold is exceeded, all subsequent pixels cache operations are to/from disk.
      </p>

      <h4>Argument</h4>

      <p>A number of megabytes to set.</p>
    </div>

    <div class="sig">
      <h3 id="set_log_event_mask">set_log_event_mask</h3>

      <p>Magick.set_log_event_mask(<span class="arg">event_list</span>)</p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>Specify which events to log.</p>

      <h4>Argument</h4>

      <p>A string composed of one or more of the following event types. If more than one event type is specified, separate the event types with commas.</p>

      <p>
        <code>All, Annotate, Blob, Cache, Coder, Configure, Deprecate, Draw, Exception, Locale, Module, None, Resource, Trace, Transform, User, Wand, X11</code>
      </p>

      <h4>Example</h4>

      <pre class="language-ruby">Magick.set_log_event_mask("Module,Coder")</pre>

      <h4>Magick API</h4>

      <p>SetLogEventMask</p>

      <h4>See also</h4>

      <p><a href="#set_log_format">set_log_format</a></p>

      <h4>Log configuration</h4>

      <p>
        Magick logging is configured with the log.xml file in Magick's config directory. See
        <a href="https://imagemagick.org/script/resources.php">Resources</a> in the ImageMagick documentation for more information.
      </p>

      <p>Use this command to find out about the current log configuration.</p>
      <pre class="language-console">convert -list log</pre>
    </div>

    <div class="sig">
      <h3 id="set_log_format">set_log_format</h3>

      <p>Magick.set_log_format(<span class="arg">format</span>)</p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>Specify the event log format.</p>

      <h4>Argument</h4>

      <p>A fprintf-like format string composed of optional "normal" text (to which no meaning is assigned) and the following format characters:</p>

      <dl>
        <dt>%d</dt>

        <dd>domain</dd>

        <dt>%e</dt>

        <dd>event</dd>

        <dt>%f</dt>

        <dd>function</dd>

        <dt>%l</dt>

        <dd>line</dd>

        <dt>%m</dt>

        <dd>module</dd>

        <dt>%p</dt>

        <dd>process ID</dd>

        <dt>%r</dt>

        <dd>read CPU time</dd>

        <dt>%t</dt>

        <dd>wall clock time</dd>

        <dt>%u</dt>

        <dd>user CPU time</dd>

        <dt>%%</dt>

        <dd>percent sign</dd>

        <dt>\n</dt>

        <dd>newline</dd>

        <dt>\r</dt>

        <dd>carriage return</dd>
      </dl>
    </div>

    <p class="spacer">&nbsp;</p>

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