Implementing Advanced FF/RW

After you create the normal speed file and trick mode speed files, the files must be placed in a location accessible by the client. The Windows Media server provides the client with the information it needs to connect to the server and receive the content by using an announcement file (a Windows Media metafile with an .asx file name extension). The announcement contains a reference to a .tmi file that contains the URLs of the normal speed file and trick mode speed files.

The following is an example of a basic announcement file that contains a reference to a .tmi file (mycontent.tmi):

<asx version = "3.0">
	<entry>
		<ref href = "mms://server1/mycontent.tmi"/>
	</entry>
</asx>

A .tmi file resides on the server and provides the server with the locations of the normal speed file and trick mode speed files so that the server can stream the files to the client upon request. A .tmi file is based on the Extensible Markup Language (XML).

The following example shows the elements in a .tmi file:

<?tmi version="1.0"?>
<tmi>
	<media src="file://C:\wmpub\WMRoot\myFile_1x.wmv" rate="1"/>
	<media src="file://C:\wmpub\WMRoot\myFile_5x.wmv" rate="5"/>
</tmi>

A .tmi file contains the following elements:

tmi
media, nested inside the tmi element

Each tmi element can include up to 10 media elements. media elements correspond to the normal speed and trick mode speed files.

The media element includes two attributes:

src, the location of the normal speed file and trick mode speed files
rate, the speed at which the normal speed file and trick mode speed files are played

The src attribute specifies the location of the normal speed and trick mode speed files. The location value can be a fully qualified URL or a relative URL. If relative, it will be resolved to a fully qualified URL by using the location of the .tmi file on the server as the base URL. The rate attribute specifies the speed factor for the file referenced in the src attribute.

If more than one trick mode speed file is referenced, you can add another media element to the tmi element. For example, if you want to add trick mode speed file that plays 10 times faster than a normal speed file, add the following media element to the .tmi file:

<media src="file://C:\wmpub\WMRoot\myfile_10x.wmv" rate="10"/>

You can create or edit a .tmi file by using a text editor, such as Notepad, or an XML editing program.

Note Image Notes

If the src attribute does not reference a file with a .wmv file name extension, a "file not found" error is displayed in the client.
If a client makes a rate request for which you have not created a corresponding entry in the .tmi file, the server fulfills the request using standard trick mode instead.
Trick mode speeds specified in announcement files must be whole numbers (integers). Trick mode speeds up to 10 times normal speed are supported in Windows Media Player 9 Series or later. Trick mode speeds are not restricted in Windows CE version 5.0 or later.

Implementing Advanced FF/RW

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