Image Difference You can create a new image that is the difference between 2 other images. my $diff = $img->difference(other=>$other_img); For each pixel in $img that is different to the pixel in $other_img, the pixel from $other_img is given, otherwise the pixel is transparent black. This can be used for debugging image differences ("Where are they different?"), and for optimizing animated GIFs. Note that $img and $other_img must have the same number of channels. The width and heigh of $diff will be the minimum of each of the width and height of $img and $other_img.