Imagick
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Imagick::setCompressionQuality

(PECL imagick 0.9.10-0.9.9)

Imagick::setCompressionQuality — Sets the object's default compression quality

说明

bool Imagick::setCompressionQuality ( int $quality )

Sets the object's default compression quality.

参数

quality

返回值

成功时返回 TRUE .

Imagick
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PHP手册 - N: Sets the object's default compression quality

用户评论:

charles dot hall at sas dot com (03-Aug-2010 07:31)

I had to insert a call to "stripImage()" in order to actually see the filesize shrink.

<?php
   $img = new Imagick();
   $img->readImage($src);
   $img->setImageCompression(imagick::COMPRESSION_JPEG);
   $img->setImageCompressionQuality(90);
   $img->stripImage();
   $img->writeImage($dest);
?>

deeps chennai (18-Mar-2010 10:59)

A note for people who just couldn't get this working..

With PHP 5.1.6, the below works:

<?php
$img->setCompression(Imagick::COMPRESSION_JPEG);
$img->setCompressionQuality(80);
?>

However, with higher versions of PHP (I tried on PHP 5.2.10), the code has no effect (and there are no exceptions or warnings thrown by Imagick as well).

The code that works instead is:

<?php
$img->setImageCompression(Imagick::COMPRESSION_JPEG);
$img->setImageCompressionQuality(80);
?>

and this is backwards compatible (Works on PHP 5.1.6 as well as 5.2.10)

nVaux.com (27-Mar-2008 04:24)

Sebastian's example works excellent, just one minor spelling mistake, it will give you an error otherwise.

<?php
$img->setCompression(Imagick::COMPRESSION_JPEG);
$img->setCompressionQuality(80);
?>

I used Sebastians example, and made one that compresses all the images within a directory:

<?php
$images = new Imagick(glob('images/*.jpg'));

foreach($images as $image)
{
    // compression methods, see "Contants"-page for Imagick
    $image->setCompression(imagick::COMPRESSION_JPEG);
    // a value between 1 and 100, 1 = high compression, 100 low compression
    $image->setCompressionQuality(80);
    $image->writeImage();
}

?>

sebastian dot moser at gmail dot com (17-Nov-2007 10:46)

Use this example to see how image compression works:

<?php
// load an image
$img = new Imagick("test.jpg");

// compression methods, see "Contants"-page for Imagick
$img->setComression(Imagick::COMPRESSION_JPEG);
// a value between 1 and 100, 1 = high compression, 100 low compression
$img->setComressionQuality(80);

// set content type
header("Content-type: image/jpeg");
// write image
echo $img->getImageBlob();
?>