(PECL imagick 2.0.0)
Imagick::chopImage — Removes a region of an image and trims
$width
   , int $height
   , int $x
   , int $y
   )Removes a region of an image and collapses the image to occupy the removed portion.
width
     Width of the chopped area
height
     Height of the chopped area
x
     X origo of the chopped area
y
     Y origo of the chopped area
   Returns TRUE on success.
  
Throws ImagickException on error.
Example #1 Using Imagick::chopImage():
Example of using Imagick::chopImage
<?php
/* Create some objects */
$image = new Imagick();
$pixel = new ImagickPixel( 'gray' );
/* New image */
$image->newImage(400, 200, $pixel);
/* Chop image */
$image->chopImage(200, 200, 0, 0);
/* Give image a format */
$image->setImageFormat('png');
/* Output the image with headers */
header('Content-type: image/png');
echo $image;
?>