Imagick::convolveImage

(PECL imagick 2, PECL imagick 3)

Imagick::convolveImage — Applies a custom convolution kernel to the image

说明

public Imagick::convolveImage ( array $kernel , int $channel = Imagick::CHANNEL_DEFAULT ) : bool

Applies a custom convolution kernel to the image.

参数

kernel: The convolution kernel
channel: Provide any channel constant that is valid for your channel mode. To apply to more than one channel, combine channeltype constants using bitwise operators. Refer to this list of channel constants.

返回值

成功时返回 true。

错误／异常

错误时抛出 ImagickException。

范例

Example #1 Imagick::convolveImage()


<?php
function convolveImage($imagePath, $bias, $kernelMatrix) {
    $imagick = new \Imagick(realpath($imagePath));    
    //$edgeFindingKernel = [-1, -1, -1, -1, 8, -1, -1, -1, -1,];
    $imagick->setImageBias($bias * \Imagick::getQuantum());
    $imagick->convolveImage($kernelMatrix);
    header("Content-Type: image/jpg");
    echo $imagick->getImageBlob();
}

?>

User Contributed Notes

ahmed at zigzapps dot com 04-Nov-2019 12:57


The provided example is wrong. Here's a correct sample:



$matrix = [[1,-1,1],[-1,1,-1],[1,-1,1]];

$kernel = \ImagickKernel::fromMatrix($matrix); 



$imagick = new Imagick();

$imagick->readimage($file.'/z.png');

$imagick->convolveImage ($kernel);

$imagick->writeimage('convolve.png');

$imagick->clear();

$imagick->destroy();

peter at musicalsaw dot com 25-Sep-2013 10:22


Example of convolveImage:



<?php

// run an edge detection filter on an image

$image = new imagick( "diana.png" ); 

$edgeArray = array(-1,-1,-1,-1,8,-1,-1,-1,-1);

$image->convolveImage ($edgeArray);

$image->thresholdImage(1);

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

echo $image;

?>