(PECL imagick 3 >= 3.3.0)
Imagick::rotationalBlurImage — Rotational blurs an image
$angle, int $channel = Imagick::CHANNEL_DEFAULT): boolRotational blurs an image.
angleThe angle to apply the blur over.
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
     
   Returns true on success.
  
Example #1 Imagick::rotationalBlurImage()
<?php
function rotationalBlurImage($imagePath) {
    $imagick = new \Imagick(realpath($imagePath));
    $imagick->rotationalBlurImage(3);
    $imagick->rotationalBlurImage(5);
    $imagick->rotationalBlurImage(7);
    header("Content-Type: image/jpg");
    echo $imagick->getImageBlob();
}
?>