Creating Playlist Parser Plug-ins
Windows Media Services uses a playlist parser plug-in to parse a playlist and create a corresponding tree structure in memory. The memory structure is called a playlist object, and it must contain SMIL 2.0 XML syntax. The server does not use a playlist directly to determine what content to send to a client. Instead, it uses the playlist object.
Windows Media Services includes the WMS Directory Playlist Parser plug-in that you can use to stream Windows Media files from a directory, and the WMS SMIL Playlist Parser plug-in that you can use to parse playlist files that conform to SMIL 2.0. If you want to use an alternate playlist file format as a source, you must create your own plug-in. For example, if you want to source a playlist from a file that contains only a flat list of media file names or a file that contains XML that does not conform to SMIL 2.0, you must create your own plug-in. The plug-in must understand the format of the playlist source and create a playlist object that conforms to SMIL 2.0.
The following sections discuss how to create custom playlist parser plug-ins.