There are many ways to create and edit server-side playlists. You can use the Playlist
Editor, the Source tab of the publishing point, an
Extensible Markup Language (XML) editor, or a text editor. The
following list provides some guidelines for using each method:
Playlist Editor. The Playlist Editor provides a simple,
graphical interface for creating playlists and specifying
attributes for the items in the
playlist. When the playlist is saved to a playlist file, it will be
saved using the correct XML syntax and structure. You can access
the Playlist Editor from the Summary tab of the
Publishing Points console tree item or by clicking the
View Playlist Editor button on the Source tab of a
publishing point.
Source tab. The Source tab includes an embedded
version of the Playlist Editor that you can use to edit playlists
that are currently assigned to publishing points. You can modify
playlist files at any time by using the toolbar on the
Source tab. If you change a playlist while the publishing
point is streaming, the change affects users in two ways:
If you are streaming from an on-demand publishing point, users
who connect to the publishing point after you change and save the
playlist receive the content specified by the new playlist, while
users who were connected to the publishing point before you changed
the playlist continue to receive the content specified by the old
playlist.
If you are streaming from a broadcast publishing point, all
connected users receive content from the new playlist as soon as
you make the change. However, if you do not the save the changes to
the playlist file, the previous version of the playlist will be
used when the broadcast publishing point is stopped and
restarted.
Text or XML editor. If you are familiar with XML syntax
and with creating XML documents, you can use this knowledge create
and edit playlist files. By using a text or XML editor, you can add
comments to your file and modify all XML elements
and attributes.
Notes
The Playlist Editor can also be opened as a
standalone program by double-clicking the wmseditor.exe
file, which can be found in the folder in which you installed the
administrative interface. By default, this is
%systemroot%\System32\Windows Media\Server\Admin\MMC.
If you are using multicast distribution with your
playlist file, you should only add content to a currently playing
playlist if the content is in a known stream format. If the content
is in a stream format that is not identified in the multicast
information file, players receiving the multicast will be in an
indefinite waiting state.
You can include a multicast stream as a content
source in a playlist by specifying the URL to the multicast
information file as a src attribute of a media
element. To do this, the playlist that references the multicast
stream must already be assigned to a broadcast publishing point.
Then, using the Source tab in the Windows Media Services
snap-in, add a media element that sources from the multicast
stream. You cannot add a multicast stream to a playlist by using
the Windows Media Playlist Editor.
Content streamed by Windows Media Services must
meet the minimum supported content length of the player to ensure
reliable playback. The minimum supported content length for Windows
Media Player 9 Series or later or a player that uses the Windows
Media Player 9 Series ActiveX control is 5 seconds. The minimum
supported content length for previous versions of Windows Media
Player is 30 seconds.
If your playlist includes JPEG image files, do
not include any syntax in your playlist that would cause the image
to pause while rendering on the client's computer. Pausing a JPEG
image in this manner can cause the player to enter a permanent wait
state. If you must show a still image under these circumstances,
create a video file of that image and then use the video file in
the playlist instead.
If your playlist includes JPEG image files and
you are using the playlist file with a broadcast publishing point,
be aware that users who connect to the broadcast while the JPEG
image is being streamed will not receive the image. They will
instead see a black screen. Once the playlist continues on to the
next item, playback will continue as expected. If you want a JPEG
image to be displayed for a certain period of time, you should use
the repeatCount attribute to repeat the image for short durations
that together equal the amount of time that the image is to be
displayed. That way, players that connect while the image is being
streamed can receive the image when it repeats. For example, if a
JPEG image is to be displayed for 60 seconds, you could set a dur
attribute value of five seconds and a repeatCount attribute value
of 12. If a user connects two seconds into the broadcast, the image
would be displayed after three seconds. If the repeatCount and dur
attribute values were not used, the user would see a black screen
for 58 seconds.