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<Imagick::segmentImageImagick::separateImageChannel>
^ImagickLast updated: Mon, 26 Oct 2026

Imagick::selectiveBlurImage

(PECL imagick 3 >= 3.3.0)

Imagick::selectiveBlurImage — Selectively blur an image within a contrast threshold

Description

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

Selectively blur an image within a contrast threshold. It is similar to the unsharpen mask that sharpens everything with contrast above a certain threshold.

Parameters

radius

sigma

threshold

channel

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

Return Values

Returns true on success.

Examples

Example #1 Imagick::selectiveBlurImage()

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

?>


<Imagick::segmentImageImagick::separateImageChannel>
^ImagickLast updated: Mon, 26 Oct 2026