1. A method of processing a media file, said media file being adapted for rendering by an application program executed by a computing device, said method comprising: determining whether a user-selected image file corresponding to media content contained in the media file is stored in a memory accessible by the computing device executing the application program; if not, determining whether a third-party image File accessible by the computing device corresponds to the media content contained in the media file; and displaying either the user-selected image file or the third-party image file as determined when the application program renders the media file corresponding thereto.