(PECL imagick 2.0.0)
Imagick::setImageOpacity — Sets the image opacity level
$opacity
) : boolSets the image to the specified opacity level. 此方法在Imagick基于ImageMagick 6.3.1以上版本编译时可用。 This method operates on all channels, which means that for example opacity value of 0.5 will set all transparent areas to partially opaque. To add transparency to areas that are not already transparent use Imagick::evaluateImage()
opacityThe level of transparency: 1.0 is fully opaque and 0.0 is fully transparent.
成功时返回 TRUE。
Example #1 A Imagick::setImageOpacity() example
An example of using Imagick::setImageOpacity()
<?php
/* Create the object */
$image = new Imagick('source.png');
/* Set the opacity */
$image->setImageOpacity(0.7);
/* output the image */
header('Content-type: image/png');
echo $image;
?>