Imagick::unsharpMaskImage

(PECL imagick 2, PECL imagick 3)

Imagick::unsharpMaskImageSharpens an image

说明

public Imagick::unsharpMaskImage ( float $radius , float $sigma , float $amount , float $threshold , int $channel = Imagick::CHANNEL_DEFAULT ) : bool

Sharpens an image. We convolve the image with a Gaussian operator of the given radius and standard deviation (sigma). For reasonable results, radius should be larger than sigma. Use a radius of 0 and Imagick::UnsharpMaskImage() selects a suitable radius for you.

参数

radius

sigma

amount

threshold

channel

返回值

成功时返回 true

错误/异常

错误时抛出 ImagickException。

范例

Example #1 Imagick::unsharpMaskImage()

<?php
function unsharpMaskImage($imagePath$radius$sigma$amount$unsharpThreshold) {
    
$imagick = new \Imagick(realpath($imagePath));
    
$imagick->unsharpMaskImage($radius$sigma$amount$unsharpThreshold);
    
header("Content-Type: image/jpg");
    echo 
$imagick->getImageBlob();
}

?>

User Contributed Notes

Anonymous 24-Feb-2009 08:00
Prepare photo for web

<?php
$im
= new Imagick($SrcFile);

$im->resizeImage ( $Width, $Height , Imagick::FILTER_QUADRATIC , 1 );
       
$im->normalizeImage();
$im->unsharpMaskImage(0 , 0.5 , 1 , 0.05);
       
$im->setImageFormat( "jpg" );
$im->setCompressionQuality(75);

$im->writeImage( $OutFile );
       
$im->removeImage();
?>