Imagick::setImageMatte

(PECL imagick 2, PECL imagick 3)

Imagick::setImageMatteSets the image matte channel

说明

public 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;

?>