src
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src
The src attribute specifies the URL for a media element.
Syntax
src = String-value
Remarks
The WMS SMIL Playlist Parser plug-in enforces case sensitivity on the src attribute.
In most cases, you must add a URL prefix to the string to indicate what data source plug-in the server must use to read the content. The following table identifies the supported URL prefixes.
Data source plug-in | URL prefix | Description |
WMS File Data Source | file:// | Enables a Windows Media server to read from playlist and media files stored on a FAT, FAT32, NTFS, or CIFS file system. |
WMS HTTP Download Data Source | httpd:// | Enables a Windows Media server to download playlists from a Web server ASP page. |
WMS Network Data Source | https:// rtsp:// rtspt:// rtspu:// |
Enables a Windows Media server to pull a distribution stream from an upstream server or encoder. |
WMS Push Data Source | push: | Enables push distribution from an encoder to a Windows Media server. |
If you do not include a prefix when specifying the URL, the server attempts to use the WMS File Data Source plug-in to read the content. Therefore, the following two URLs are equivalent.
file://c:\wmpub\wmroot\movie.wmv c:\wmpub\wmroot\movie.wmv
The following example illustrates how to retrieve the URL Prefix and URL Suffix properties for the first data source plug-in in the collection.
' Create a WMSServer object. Dim Server As WMSServer Set Server = New WMSServer ' Retrieve the URL prefix and suffix. Dim Value As String Value = Server.DataSources(0).Properties("URL Prefix") Value = Server.DataSources(0).Properties("URL Suffix")
Physical and relative URLs may be used to reference content. A physical URL identifies the actual location of the content by specifying a complete path such as c:\wmpub\wmroot\movie.wmv.
A relative URL requires a base that the server can use to create a physical URL. The base URL for a playlist is either the publishing point path or the URL used to retrieve the playlist. For example, if a client requests the following playlist from an on-demand publishing point in which the IWMSPublishingPoint.Path (Visual Basic .NET) property references c:\wmpub\wmroot, the server resolves the relative URL for media_1 to the physical URL c:\wmpub\wmroot\movie1.wmv.
<?wsx version="1.0"> <smil> <media id="media_1" src=".\movie_1.wmv" /> <media id="media_2" src="c:\movies\playlist_2.wsx" /> </smil>
The base URL for media elements in playlist_2.wsx is c:\movies\playlist_2.wsx. Therefore, if playlist2.wsx contains the following syntax, the server resolves the relative URL for media_3 to c:\movies\movie_2.wmv. The server strips playlist_2.wsx from the base URL when it creates the physical URL.
<?wsx version="1.0"> <smil> <media id="media_1" src=".\movie_2.wmv" /> </smil>
Within a relative URL, the path segment "." indicates the current hierarchy level and ".." indicates the level above that. The following table illustrates how the server resolves relative URLs for a base URL of c:\wmpub\wmroot\video\movies.
Relative URL | Physical URL |
.\movie_1.wmv | file://c:\wmpub\wmroot\video\movies\movie_1.wmv |
movie_1.wmv | file://c:\wmpub\wmroot\video\movies\movie_1.wmv |
\movie_1.wmv | file://c:\movie_1.wmv |
..\movie_1.wmv | file://c:\wmpub\wmroot\video\movie_1.wmv |
The following table identifies the URL syntax supported by a Windows Media server.
Syntax | Description |
file://C:\wmpub\wmroot\movie.wmv, file://\\server\movies\movie.wmv |
References a digital media file on a local or remote server. |
file://C:\wmpub\wmroot\playlist.wsx, file://\\server\movies\playlist.wsx |
References a playlist file on a local or remote server. |
https://encoder_name:port_number | References a stream from an encoder. |
rtsp://server/pubpoint, https://server/pubpoint |
References a publishing point on a local or remote server. A broadcast publishing point can use an on-demand publishing point as a source, and the reverse is also true. |
https://server/station_name, https://server1/pubpoint |
References a publishing point on a Windows Media server version 4.1. HTTP protocol must be used when the source is a V4.1 server. |
rtsp://server/pubpoint/movie.wmv | References a specific digital media file from a remote server. You can specify whether the stream is sent using UDP or TCP by changing the protocol to RTSPU or RTSPT, respectively. |
lpp://pubpoint1/movie1.wmv | References a specific digital media file on the local server. Use lpp (local publishing point) to identify the local server when the server name is not specified. Using lpp:// is more efficient because it does not use the network transport layer. |
httpd://Server/Playlist.asp, httpd://server1/playlist.wsx |
References an Active Server Page (ASP) or playlist on a Web server. |
MCast://c:\wmpub\wmroot\file.nsc | References a multicast stream using a multicast information (.nsc) file. Relative URLs cannot be used to specify this path. |
See Also
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