from here to BLOB....... and back

I want to experiment with storing and retrieving images to and from MySql as "blob" fields I've spent some time searching both the PHP and the MySql sites but I still don't know how to even start on the following ( I am using PHP and MySql for other things and have some idea of basic functions) here.gif/jpg [convert or whatever is required and insert into MySql table as] BLOB record [select convert or whatever and display as] here.gif/jpg I need to know what PHP functions to use for any conversion that may be required and any special MySql syntax that may apply to "blob" fields