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Creating Data Source Plug-ins

Note

   Custom data source plug-ins can be created only in C++. They cannot be created using C#, or Visual Basic .NET.

Data source plug-ins create data containers which are part of the data path created by a server to send digital media to a client. The data path also includes a media parser plug-in and a data sink plug-in. The following diagram illustrates a data path.

Diagram illustrating the data path.

Dd874224.wms8_genldatapath_final(en-us,VS.85).gif

Digital media can originate from a variety of sources such as a file, an encoder stream, a push distribution, a database, or other source. The data container is created by the data source plug-in and the data container accesses data from a source and places the appropriate amount of data into a buffer for use by the media parser plug-in or playlist parser plug-in. The media parser creates a packet list that contains offsets into the buffer, and the data sink uses the packet list to send digital media to a client.

Different sources require the use of different data source plug-ins. You can use the plug-ins included with Windows Media Services or create your own to use with data containers not supported by Windows Media Services. The following sections discuss how to implement a data source plug-in and a data container.

Section

Description

Data Source Plug-in Overview

Discusses how data is read from a data container and describes the interaction between the server and the data path plug-ins.

Data Source Plug-in Interfaces

Identifies the interfaces that you can implement to create a custom data source plug-in.

Implementing a Data Source Plug-in

Discusses the differences between a byte-based and a packet-based data source plug-in and how to implement them.

See Also

Concepts

Programming Guide