Hi,
You should check it has been set before generating a URL with it.
I would have made this into a helper. If called I would return simply either TRUE or FALSE if resized image was created. I would also have put the location of the image either as a config item, or an option in the method.
Within this helper I would also have another function called something like 'show_image', which checks that the image exists, and returns a url to it. But, not the base_url bit, that part is for the view to add. If it did not exist, it could then call the function above to create the image as a private function.
I also always follow the naming convention of adding _model, _view, _helper to the end of my class names. So your model here would be Image_resize_model.php
However, that is all opinion, as naming conventions are not enforced, and the beauty of CI is you can do it however you want.
Good job though,
Paul.
