(PECL imagick 2.0.0)
Imagick::magnifyImage — Scales an image proportionally 2x
Is a convenience method that scales an image proportionally to twice its original size.
   Returns TRUE on success.
  
Throws ImagickException on error.
Example #1 Imagick::magnifyImage()
<?php
function magnifyImage($imagePath) {
    $imagick = new \Imagick(realpath($imagePath));
    $imagick->magnifyImage();
    header("Content-Type: image/jpg");
    echo $imagick->getImageBlob();
}
?>