php-doc-en/reference/imagick/examples.xml

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XML

<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<chapter xml:id="imagick.examples" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
&reftitle.examples;
<section xml:id="imagick.examples-1">
<title>Basic usage</title>
<para>
Imagick makes image manipulation in PHP extremely easy through an OO
interface. Here is a quick example on how to make a thumbnail:
<example>
<title>Creating a thumbnail in Imagick</title>
<programlisting role="php">
<![CDATA[
<?php
header('Content-type: image/jpeg');
$image = new Imagick('image.jpg');
// If 0 is provided as a width or height parameter,
// aspect ratio is maintained
$image->thumbnailImage(100, 0);
echo $image;
?>
]]>
</programlisting>
</example>
</para>
<para>
Using SPL and other OO features supported in Imagick, it can be simple
to resize all files in a directory (useful for batch resizing large
digital camera images to be web viewable). Here we use resize, as we might
want to retain certain meta-data:
<example>
<title>Make a thumbnail of all JPG files in a directory</title>
<programlisting role="php">
<![CDATA[
<?php
$images = new Imagick(glob('images/*.JPG'));
foreach($images as $image) {
// Providing 0 forces thumbnailImage to maintain aspect ratio
$image->thumbnailImage(1024,0);
}
$images->writeImages();
?>
]]>
</programlisting>
</example>
</para>
<para>
This is an example of creating a reflection of an image.
The reflection is created by flipping the image and overlaying a gradient on it.
Then both, the original image and the reflection is overlayed on a canvas.
<example>
<title>Creating a reflection of an image</title>
<programlisting role="php">
<![CDATA[
<?php
/* Read the image */
$im = new Imagick("test.png");
/* Thumbnail the image */
$im->thumbnailImage(200, null);
/* Create a border for the image */
$im->borderImage(new ImagickPixel("white"), 5, 5);
/* Clone the image and flip it */
$reflection = $im->clone();
$reflection->flipImage();
/* Create gradient. It will be overlayd on the reflection */
$gradient = new Imagick();
/* Gradient needs to be large enough for the image and the borders */
$gradient->newPseudoImage($reflection->getImageWidth() + 10, $reflection->getImageHeight() + 10, "gradient:transparent-black");
/* Composite the gradient on the reflection */
$reflection->compositeImage($gradient, imagick::COMPOSITE_OVER, 0, 0);
/* Add some opacity. Requires ImageMagick 6.2.9 or later */
$reflection->setImageOpacity( 0.3 );
/* Create an empty canvas */
$canvas = new Imagick();
/* Canvas needs to be large enough to hold the both images */
$width = $im->getImageWidth() + 40;
$height = ($im->getImageHeight() * 2) + 30;
$canvas->newImage($width, $height, new ImagickPixel("black"));
$canvas->setImageFormat("png");
/* Composite the original image and the reflection on the canvas */
$canvas->compositeImage($im, imagick::COMPOSITE_OVER, 20, 10);
$canvas->compositeImage($reflection, imagick::COMPOSITE_OVER, 20, $im->getImageHeight() + 10);
/* Output the image*/
header("Content-Type: image/png");
echo $canvas;
?>
]]>
</programlisting>
&example.outputs.similar;
<mediaobject>
<alt>Output of example : Creating a reflection of an image</alt>
<imageobject>
<imagedata fileref="en/reference/imagick/figures/hello_world_reflection.png"/>
</imageobject>
</mediaobject>
</example>
</para>
<para>
This example illustrates how to use fill patterns during drawing.
<example>
<title>Filling text with gradient</title>
<programlisting role="php">
<![CDATA[
<?php
/* Create a new imagick object */
$im = new Imagick();
/* Create new image. This will be used as fill pattern */
$im->newPseudoImage(50, 50, "gradient:red-black");
/* Create imagickdraw object */
$draw = new ImagickDraw();
/* Start a new pattern called "gradient" */
$draw->pushPattern('gradient', 0, 0, 50, 50);
/* Composite the gradient on the pattern */
$draw->composite(Imagick::COMPOSITE_OVER, 0, 0, 50, 50, $im);
/* Close the pattern */
$draw->popPattern();
/* Use the pattern called "gradient" as the fill */
$draw->setFillPatternURL('#gradient');
/* Set font size to 52 */
$draw->setFontSize(52);
/* Annotate some text */
$draw->annotation(20, 50, "Hello World!");
/* Create a new canvas object and a white image */
$canvas = new Imagick();
$canvas->newImage(350, 70, "white");
/* Draw the ImagickDraw on to the canvas */
$canvas->drawImage($draw);
/* 1px black border around the image */
$canvas->borderImage('black', 1, 1);
/* Set the format to PNG */
$canvas->setImageFormat('png');
/* Output the image */
header("Content-Type: image/png");
echo $canvas;
?>
]]>
</programlisting>
&example.outputs.similar;
<mediaobject>
<alt>Output of example : Filling text with gradient</alt>
<imageobject>
<imagedata fileref="en/reference/imagick/figures/hello_world.png"/>
</imageobject>
</mediaobject>
</example>
</para>
<para>
Working with animated GIF images
<example>
<title>Read in GIF image and resize all frames</title>
<programlisting role="php">
<![CDATA[
<?php
/* Create a new imagick object and read in GIF */
$im = new Imagick("example.gif");
/* Resize all frames */
foreach ($im as $frame) {
/* 50x50 frames */
$frame->thumbnailImage(50, 50);
/* Set the virtual canvas to correct size */
$frame->setImagePage(50, 50, 0, 0);
}
/* Notice writeImages instead of writeImage */
$im->writeImages("example_small.gif", true);
?>
]]>
</programlisting>
</example>
</para>
</section>
</chapter>