User`s guide

Chapter 1 Desktop
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You can also apply filters using the filter tracks and nest tracks using container tracks. For
more information, see “Working with Effects and Filters” on page 172.
The Shape Track
The shape track is the most basic type of track in Avid FX. When you create a new effect and
start Avid FX, the tracks you see are all shape tracks. By default, these tracks use the 3D
Plane shape, a still or moving image that looks exactly the same as the source image in an
Avid editing application. Other shapes map the source image onto a 3D geometric solid,
such as a sphere or cube, transforming the media assigned to the shape. For more
information, see “Composite Window Controls” on page 71. Inside each shape track are
other tracks that affect the appearance and movement of the shape.
The Mask Track
A mask is a media file with an alpha (transparency) channel used to make areas in another
image transparent. Each shape and face track contains a mask track. When you apply a mask
to an image, the image becomes transparent wherever the mask’s alpha channel has a value
of 0 and remains opaque wherever the mask’s alpha channel’s value is 255. Intermediate
alpha channel values in the mask produce semitransparent areas.
See “Upstream and Downstream Masks” on page 179.
Source Media Mask with alpha
channel
Masked output