(PECL imagick 2.0.0)
Imagick::cropImage — Extracts a region of the image
$width
   , int $height
   , int $x
   , int $y
   )Extracts a region of the image.
widthThe width of the crop
heightThe height of the crop
xThe X coordinate of the cropped region's top left corner
yThe Y coordinate of the cropped region's top left corner
   Returns TRUE on success.
  
Throws ImagickException on error.
Example #1 Imagick::cropImage()
<?php
function cropImage($imagePath, $startX, $startY, $width, $height) {
    $imagick = new \Imagick(realpath($imagePath));
    $imagick->cropImage($width, $height, $startX, $startY);
    header("Content-Type: image/jpg");
    echo $imagick->getImageBlob();
}
?>