Imagick::setImageMatte

(PECL imagick 2.0.0)

Imagick::setImageMatte — Sets the image matte channel

说明

Imagick::setImageMatte ( bool $matte ) : bool

Sets the image matte channel. 此方法在Imagick基于ImageMagick 6.2.9以上版本编译时可用。

参数

matte: True activates the matte channel and false disables it.

返回值

成功时返回 TRUE。

User Contributed Notes

martin at psinas dot com 05-Oct-2011 06:33


I found this method is needed when creating a font / image mask, and needs to be set to false otherwise the mask won't take effect. Here is an example:



<?php



// Create objects

$image = new Imagick('myImage.png');

$watermark = new Imagick();

$mask = new Imagick();

$draw = new ImagickDraw();



// Define dimensions

$width = $image->getImageWidth();

$height = $image->getImageHeight();



// Create some palettes

$watermark->newImage($width, $height, new ImagickPixel('grey30'));

$mask->newImage($width, $height, new ImagickPixel('black'));



// Watermark text

$text = 'Copyright';



// Set font properties

$draw->setFont('Bookman-Demi');

$draw->setFontSize(20);

$draw->setFillColor('grey70');



// Position text

$draw->setGravity(Imagick::GRAVITY_SOUTHEAST);



// Draw text on the watermark palette

$watermark->annotateImage($draw, 10, 12, 0, $text);



// Draw text on the mask palette

$draw->setFillColor('white');

$mask->annotateImage($draw, 11, 13, 0, $text);

$mask->annotateImage($draw, 10, 12, 0, $text);

$draw->setFillColor('black');

$mask->annotateImage($draw, 9, 11, 0, $text);



// This is apparently needed for the mask to work

$mask->setImageMatte(false);



// Apply mask to watermark

$watermark->compositeImage($mask, Imagick::COMPOSITE_COPYOPACITY, 0, 0);



// Overlay watermark on image

$image->compositeImage($watermark, Imagick::COMPOSITE_DISSOLVE, 0, 0);



// Set output image format

$image->setImageFormat('png');



// Output the new image

header('Content-type: image/png');

echo $image;



?>