(PECL imagick 2.0.0)
Imagick::embossImage — Returns a grayscale image with a three-dimensional effect
$radius
   , float $sigma
   )Returns a grayscale image with a three-dimensional effect. 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 it will choose a suitable radius for you.
radiusThe radius of the effect
sigmaThe sigma of the effect
   Returns TRUE on success.
  
Throws ImagickException on error.
Example #1 Imagick::embossImage()
<?php
function embossImage($imagePath, $radius, $sigma) {
    $imagick = new \Imagick(realpath($imagePath));
    $imagick->embossImage($radius, $sigma);
    header("Content-Type: image/jpg");
    echo $imagick->getImageBlob();
}
?>