diff --git a/reference/image/functions/imagefilter.xml b/reference/image/functions/imagefilter.xml
index dfc7f71858..0a949d3a83 100644
--- a/reference/image/functions/imagefilter.xml
+++ b/reference/image/functions/imagefilter.xml
@@ -1,10 +1,10 @@
 <?xml version='1.0' encoding='iso-8859-1'?>
-<!-- $Revision: 1.2 $ -->
+<!-- $Revision: 1.3 $ -->
   <refentry id="function.imagefilter">
    <refnamediv>
     <refname>imagefilter</refname>
     <refpurpose>
-     Applies Filter an image using a custom angle
+     Applies a filter to an image
     </refpurpose>
    </refnamediv>
    <refsect1>
@@ -15,9 +15,151 @@
      <methodparam><type>int</type><parameter>filtertype</parameter></methodparam>
       <methodparam  choice="opt"><type>int</type><parameter>args</parameter></methodparam>
     </methodsynopsis>
+    <para>
+     <function>imagefilter</function> applies the filter
+     <parameter>filtertype</parameter> to the image, using
+     <parameter>args</parameter> where necessary.
+    </para>
+    <para>
+     <parameter>filtertype</parameter> can be one of the following:
+     <itemizedlist>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_NEGATE</parameter>: Reverses all colors of
+        the image.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_GRAYSCALE</parameter>: Converts the image into
+        grayscale.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_BRIGHTNESS</parameter>: Changes the brightness
+        of the image. Use <parameter>args</parameter> to set the level of
+        brightness.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_CONTRAST</parameter>: Changes the contrast of
+        the image. Use <parameter>args</parameter> to set the level of
+        contrast.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_COLORIZE</parameter>: Like
+        <parameter>IMG_FILTER_GRAYSCALE</parameter>, except you can specify the
+        color. Use 3 separate <parameter>args</parameter>, in the form of
+        <parameter>red</parameter>, <parameter>blue</parameter>,
+        <parameter>green</parameter>. The range for each color is 0 to 255.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_EDGEDETECT</parameter>: Uses edge detection to
+        highlight the edges in the image.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_EMBOSS</parameter>: Embosses the image.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_GAUSSIAN_BLUR</parameter>: Blurs the image using
+        the Gaussian method.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_SELECTIVE_BLUR</parameter>: Blurs the image.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_MEAN_REMOVAL</parameter>: Uses mean removal to
+        achieve a "sketchy" effect.
+       </simpara>
+      </listitem>
+      <listitem>
+       <simpara>
+        <parameter>IMG_FILTER_SMOOTH</parameter>: Makes the image smoother.
+        Use <parameter>args</parameter> to set the level of smoothness.
+       </simpara>
+      </listitem>
+     </itemizedlist>
+    </para>
+    &note.bundled.gd;
+    <para>
+     &return.success;
+    </para>
+    <para>
+     <example>
+      <title><function>imagefilter</function> grayscale example</title>
+      <programlisting role="php">
+<![CDATA[
+<?php
+$im = imagecreatefrompng('dave.png');
+if ($im && imagefilter($im, IMG_FILTER_GRAYSCALE)) {
+    echo 'Image converted to grayscale.';
+    imagepng($im, 'dave.png');
+} else {
+    echo 'Conversion to grayscale failed.';
+}
 
-     &warn.undocumented.func;
-     &note.bundled.gd;
+imagedestroy($im);
+?>
+]]>
+      </programlisting>
+     </example>
+    </para>
+    <para>
+     <example>
+      <title><function>imagefilter</function> brightness example</title>
+      <programlisting role="php">
+<![CDATA[
+<?php
+$im = imagecreatefrompng('sean.png');
+if ($im && imagefilter($im, IMG_FILTER_BRIGHTNESS, 20)) {
+    echo 'Image brightness changed.';
+    imagepng($im, 'sean.png');
+} else {
+    echo 'Image brightness change failed.';
+}
+
+imagedestroy($im);
+?>
+]]>
+      </programlisting>
+     </example>
+    </para>
+    <para>
+     <example>
+      <title><function>imagefilter</function> colorize example</title>
+      <programlisting role="php">
+<![CDATA[
+<?php
+$im = imagecreatefrompng('philip.png');
+
+/* R, G, B, so 0, 255, 0 is green */
+if ($im && imagefilter($im, IMG_FILTER_COLORIZE, 0, 255, 0)) {
+    echo 'Image successfully shaded green.';
+    imagepng($im, 'philip.png');
+} else {
+    echo 'Green shading failed.';
+}
+
+imagedestroy($im);
+?>
+]]>
+      </programlisting>
+     </example>
+    </para>
    </refsect1>
   </refentry>