User Manual

Alternately, you can add a timeline matte to the Media Pool, which isn’t attached to any clip, that
can be used as a key source in the Color page within any clip’s Clip grade, or within a Timeline
Grade. Timeline mattes appear as stand-alone clips in the Media Pool.
A timeline matte, seen in Thumbnail view
What Are Mattes For?
Matte files are useful for two things. Traditionally, mattes are grayscale media files that identify
regions of varying opacity, with white representing solid areas, and black representing
transparency. For example, exported clips from a compositing application sometimes are
accompanied by one or more matte files that correspond to keys or rotoscoped mattes from the
composite. By importing these matte files using the “Add as Matte” command, you can attach
them to the clips they belong to in the Media Pool, so that they’re only available to the clips
they’re synced to.
However, mattes can also be used as creative tools to apply grain and texture for effect. What a
matte does depends on how you connect it in the Node Editor of the Color page. These are
media files that you may want to use as mattes for potentially any clip, so they can also be
added to the Media Pool as a so-called timeline matte, that can be applied to any clip you want.
TIP: If necessary, you can also apply LUTs to both clip mattes and timeline mattes in
the Media Pool, simply by right-clicking a matte, and choosing a LUT from the 1D LUT
or 3D LUT submenus. This can be helpful for adjusting incorrectly formatted mattes.
Adding Mattes
To use mattes, you need to add them in very specific ways.
To assign a matte to a clip in the Media Pool:
1 Select a clip in the Media Pool to which you want to attach an external matte.
2 Select the matching external matte file in the Media Storage panel, right-click it, and
choose Add to Media Pool as a Matte.
The matte is attached to the clip as a clip matte. A badge indicates that clip has a
mattewhen the Media Pool is in Icon view, and the matte itself can be seen, if you put
the Media Pool into List view, appearing as a nested item underneath the clip it’s
attached to.
Removing mattes from clips in the Media Pool:
1 Put the Media Pool into List view.
2 Right-click the external matte file you need to remove, and choose Remove
SelectedClips.
Chapter – 11 Adding and Organizing Media with the Media Pool 305