- Document imagefilter() and add examples.

git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@163852 c90b9560-bf6c-de11-be94-00142212c4b1
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Dave Barr 2004-07-21 08:00:06 +00:00
parent a249209d0c
commit 8cfe821840

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@ -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>