Alcorn Mcbride Digital Video Machine 4, Руководство пользователя

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Playlists 35
Playlists
Playlists provide a mechanism for the DVM4 to automatically execute a series
of commands in a predefined sequence. Playlists often allow the unit to be used
to perform complex functions that would normally require an external
controller. Playlists can perform functions as simple as looping a single clip, or
more complex functions like synchronizing multiple clips. All commands
available to the Serial, UDP, and scheduler interfaces are available to the playlist
interface. However, there is a difference in the way that the
channel number
portion is handled. This number is dynamically inserted according to the
channel in which the playlist has been assigned. This means that you should not
include the channel number in your list of playlist commands. For a list of all
the commands at your disposal, see the
General Command Summary section.
IMPORTANT NOTE: Since the playlist automatically inserts the channel
number in all playlist commands, commands that do not accept channel numbers
should
NOT be used. A few examples would be the Play Group command or
the Send Serial String command
Playlist Engines
The DVM4 has 1 playlist engine for every channel (that’s a total of 4 if math is
not your thing). You search and execute playlists just like you search and play
video files. However, unlike a video file, commands in the playlists can control
all aspects of the DVM4. For example, you could have one playlist control
banners and images on all channels while another controls videos. Once you
gain an understanding of how the playlist engines function, the combinations of
tasks you can perform are endless.
Commands may be entered into the Playlist in either upper or lower case. All
text following a semicolon (;) is interpreted as comments, until the next carriage
return. You may put anything you want in comments, including the special
command characters normally used in the Playlist.
Playlist files are stored in
the PLAYLISTS directory.
Playlist Channels
One thing that is nice about the DVM4 playlist structure is that you do not have
to specify a channel number. Channel numbers are automatically inserted into
your command string when the playlist is searched.