Containers are a convenient way of grouping elements on the timeline. The elements, which can come from different layers, can be edited as a unit and individually. A matte container is a container with the RGB portion of an image on one track and its matte on another. If the matte for a clip exists separately from it, you can add the clip and its matte to the timeline as a single element by creating a matte container for them.

For single-frame mattes and virtual sources, there are special considerations. If the matte consists of a single frame, it is automatically repeated to match the duration of the front clip. If both the front and matte clips are virtual sources, the matte container is created as a virtual source. You can trim, slip or slide it to any extent.

You can create a matte container in the following ways:

• Using the Axis soft effect quick menu or editor.
• By importing the RGBA file directly into a matte container. See Importing RGBA Files. (This option does not repeat single-frame mattes to match the front clip.)

To create a matte container using the quick menu:

1. Load your fill to the timeline and apply a soft Axis to it.
2. In the Axis quick menu, click Matte.
3. Select your external matte from the Desktop.
   NoteYou cannot use a timeline element as your matte selection.

   A matte container is created.

To create a matte container using the editor:

1. Load your fill to the timeline and apply a soft Axis to it.
2. Enter the Axis Editor.
3. Click Load Matte.

   
   

4. Select your external matte from the Desktop.
   NoteYou cannot use a timeline element as your matte selection.

   The matte container is created.

To enter a matte container:

1. Double-click the matte container or click E beside the Container button.

   The matte container contains two tracks: your fill on V1 and the external matte you selected on V2. You edit the contents of a matte container the same way as a normal container.

To mute a matte from the Axis Editor:

1. Select the matte container.
2. Enter the Axis Editor.
3. Select Off from the Matte box.

   The matte is temporarily removed from the vertical edit.

To mute a matte from the timeline:

1. Click the Container button.

   The LED turns yellow.

   NoteTo unhide the matte, click the Container LED button so that it turns purple.