Workflows

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In the above example with the spinning DVD flying by, you would most likely want to
be able to see the start or end frame video through the DVD’s hole and around its
edges. For this to happen, there must be an alpha channel for DVD Studio Pro to know
which parts of the asset movie video should appear and which should be ignored.
There are two ways to provide this alpha channel: embedded with the asset movie or
as a separate asset matte movie (described in “Asset Matte Movie,” below).
Important: When the alpha channel is embedded with the asset movie, be sure the
video output is premultiplied.
If your transition does not require the start and end frame video to be on the screen
at the same time, you can add a switch point marker to the asset movie to control
when the transition switches from showing the start frame to showing the end
frame. If you do want to have both the start and end frame video on the screen at
the same time, you must use a background matte movie (described in “Background
Matte Movie” on page 44).
If the transition asset folder does not contain a background matte movie,
DVD Studio Pro does the following to set the switch point:
 DVD Studio Pro first looks in the asset movie to see if there is a marker named
TransitionSwitchPoint. If present, this marker is used as the switch point. You can add
this marker to the asset movie in Motion by choosing DVD Alpha Transition from the
Edit Marker’s Type pop-up menu.
 If not present, DVD Studio Pro looks to see if there are any markers in the asset
movie. If present, the first marker is used as the switch point.
 If no markers are present in the asset movie, the switch point is set to the asset
movie’s halfway point.
Asset Matte Movie
The white areas define
where the asset movie
video appears.
The black areas define
where the background
video (start or end frame,
depending on the switch
point or background
matte movie) appears.
The gray areas define
where the asset movie
video appears, but is
transparent.