Creating and Importing a Motion Project as an Alpha Transition

Creating an Alpha Transition requires from one to three QuickTime movies, depending on the type of transition you want to create.

• Do you want any kind of video other than the start and end frames to appear during the transition? For example, if you want a spinning DVD to fly across the screen during the transition, you must have an asset movie providing the flying DVD image.
• Do you want to see the start and end frames on the screen at the same time during the transition? In the example with the spinning DVD, maybe you want to see the start frame around the outside edge of the DVD and the end frame in the DVD’s center. To see the start and end frames at the same time, you must have a background matte movie.
• Do you want a simple wipe transition that uses a custom shape? You can use a background matte movie to create a wipe transition with hard or soft edges in any shape you like.

There are several components to an Alpha Transition:

• Asset folder
• Asset movie
• Asset matte movie
• Background matte movie

1. Start frame (red in this example)
2. End frame (blue in this example)
3. The DVD image is from the asset movie, with an asset matte movie controlling where the background video appears.

Note: The background matte movie (not visible) controls whether the background shows the start or end video.

Each component is described in the following sections.

Asset Folder

Motion projects and movies used as Alpha Transitions within DVD Studio Pro are handled differently than Motion projects and movies used in menus and tracks. When opened, DVD Studio Pro checks for transition asset folders located in specific areas of your hard disk. Any folders it finds that contain appropriate Motion projects or movies are automatically added as Alpha Transitions, and become available for use in any DVD projects you author.

In addition to containing the movies that make up the Alpha Transition, the name of the asset folder becomes the name of the transition. All files within the folder must also be named the same as the folder, with “-matte" added to asset matte movies and “-backgroundMatte" added to background matte movies to distinguish between them.

When you open DVD Studio Pro, it looks in two locations for asset folders:

• At the root of your disk, in this location:
  [Startup Disk]/Library/Application Support/DVD Studio Pro/Transitions
• In your home folder, in this location:
  [Home]/Library/Application Support/DVD Studio Pro/Transitions

Note

: If you add an asset folder while DVD Studio Pro is open, it is ignored until the next time you open DVD Studio Pro.

Asset Movie

1. The asset movie can contain an alpha channel to control where the background appears.
2. The asset movie provides transition video in addition to the start and end frames.

The asset movie is required if you want any kind of video other than the start and end frames to appear during the transition. For example, if you want a spinning DVD to fly across the screen during the transition, it is the asset movie that provides the flying DVD image.

The asset movie must have the same name as the asset folder and can have an extension. For example, if the asset folder’s name is Spinning DVD, the asset movie could be named Spinning DVD.mov.

There are two optional aspects to the asset movie: an alpha channel and a switch point.

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 42 of the Final Cut Studio Workflow PDF).

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 selecting DVD Alpha Transition in 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

1. The black areas define where the background video (start or end frame, depending on the switch point or background matte movie) appears.
2. The white areas define where the asset movie video appears.
3. The gray areas define where the asset movie video appears, but is transparent.

The asset matte movie is required only when an asset movie that does not include an alpha channel is used by the transition. Having a separate asset matte movie is particularly useful when the asset movie is normal video (as opposed to an animation).

The asset matte movie must have the same name as the asset folder, followed by “-matte," and can have an extension. For example, if the asset folder’s name is Spinning DVD, the asset matte movie could be named Spinning DVD-matte.mov.

The asset matte movie needs to be monochrome, with white identifying the asset movie video to use, and black identifying the places where the start or end frame video appears. You can also use levels in between white and black to set transparency and add soft edges.

Background Matte Movie

1. The black areas define where the end frame background video appears.
2. The white areas define where the start frame background video appears.

The background matte movie can be used in two ways:

• It can be used in conjunction with the asset movie to control which areas of the screen should show the start frame video and which should show the end frame video.
• It can be used as the only movie in the transition assets folder to provide a wipe transition. As when used with the asset movie, the background matte movie controls which areas of the screen should show the start frame video and which should show the end frame video.

The background matte movie must have the same name as the transition asset folder, followed by “-backgroundMatte," and can have an extension. For example, if the transition asset folder’s name is Spinning DVD, the background matte movie could be named Spinning DVD-backgroundMatte.mov.

The background matte movie needs to be monochrome, with white identifying where the start frame video appears, and black identifying where the end frame video appears. As a general rule, the background matte movie should start with a full white screen and end with a full black screen. You can also use levels in between white and black to set transparency and add soft edges.

This information comes from the Final Cut Studio Workflow PDF. It and other PDF manuals are available under the Help menu.