MACROMEDIA DIRECTOR MX-USING DIRECTOR MX, Руководство пользователя

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Using Video 345
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If you use RealPlayer native audio to process RealAudio, all Lingo sound elements and the
audio property in the Property inspector are ignored. You enable RealPlayer native audio by
setting the
realPlayerNativeAudio()
function to
TRUE
. This function should be executed
in a
prepareMovie
event handler in a movie script. This is a system-level function that you can
only set using Lingo, so you must set it before the first RealMedia cast member is encountered
in the Score, which causes Director to load the RealPlayer engine. Once the RealPlayer is
loaded, changes to this function are ignored.
RealMedia stream playback
In Director, RealMedia playback occurs at the cast member level, not the sprite level. Therefore, if
you have two sprites of a cast member, and you apply a command or property to one of the
sprites, the command will be applied to both of the sprites. For example, if you select the Display
Real Logo check box (or call the corresponding
displayRealLogo
Lingo property in a script) for
one of the sprites, the Display Real Logo check box is automatically selected for both of the
sprites, and the RealNetworks logo is displayed when either sprite plays. This is true for all
methods and properties, not just the
displayRealLogo
property.
If your movie contains more than one RealMedia sprite (not playing at the same time) that
reference the same cast member, you may want to create two cast members referencing the same
URL, so that the sprites can be controlled independently. Sprites that reference the same cast
member are subject to the methods and properties of the member.
Streaming
Streaming is the most efficient and user-friendly method of downloading, viewing, and listening
to video and audio content on the Internet. Users can begin viewing content as soon as a small
portion (usually a few seconds) of the file has downloaded. As the stream plays, the rest of the
stream continues to download in the background.
If you understand how the streaming process works in Director, and for RealMedia cast members
in particular, you can minimize the amount of time users must wait before your content begins to
play in the browser.
The Shockwave player first downloads the Score information, scripts, and information about the
size and shape of each cast member, and then downloads the media in the cast members as they
are played in the movie. When a RealMedia cast member begins to play, the streaming process
begins and cycles through the various states. If you are viewing content in the RealMedia viewer,
the
mediaStatus
property value that corresponds to the state in the streaming process is
displayed in the status bar.
During the seeking or buffering state (
mediaStatus #buffering
), RealMedia cast members are
downloading into a buffer that holds the portion of the stream that is about to play. This initial
loading of the buffer is what causes the delay between the call to the
play
command (in the Score
or user initiated) and the actual playing of the stream. Once the stream begins to play, the
information in the buffer is continually updated with the next portion of the stream to be played,
and the stream plays without interruption. For more information, see the entry for
percentBuffered
in this document.
When using Lingo with RealMedia cast members, you need to know which streaming state the
cast member has reached, or script errors can result. For complete information on the order of the
states in the streaming process and the impact on RealMedia cast members, see the
state
(RealMedia)
and
mediaStatus
entries in this document.