You can't. Without uploading the image PHP can't do anything at all to the image. PHP runs on the server, therefore it needs to have the image uploaded to the server for it to be able to interact with it.
Perhaps Javascript may be a better alternative if you don't want to upload the image.
forum216
----------------------------------
Ignorance is not necessarily Bliss, case in point:
Unknown has caused an Unknown Error on Unknown and must be shutdown to prevent damage to Unknown.