Is there a way to change the crop position of an image to "top left" instead of "center center" when generating an image trough $img_path = $im->getThumbnail(...) ?

Or alternatively, can I hijack the location where an image Thumbnail would be generated and generate my own version trough image magick?

(I don't need to know how to create a pic trough image magick, only how to find out a possible storage location and storage name, so I can take over and do my own creation of the thumbnail).