Using the After Effects Mask Tracker

The mask tracker transforms a mask so that it follows the motion of an object (or objects) in a movie. You usually create and use masks to hide clips from the final output, select a part of the image or video to apply effects, or combine clips from different sequences.

Mask tracker controls

To use the mask tracker, select a mask and click the Mask Path setting under the mask. Right-click the selected mask and select Track Mask to begin tracking a mask.

When a mask is selected, the Tracker panel switches to mask tracking mode, and displays the following controls:

  • Track forward either one frame at a time or until the end of the layer.
  • Track backward either one frame at a time or until the end of the layer.
  • Different methods with which you can choose to modify position, scale, rotation, skew, and perspective of the mask.

If the Tracker panel is not displayed, select a mask and go to Animation > Track Mask to display the panel. You can also context-click a mask and choose Track Mask from the context menu.

The result of using the mask tracker can be seen in the application of keyframes for the Mask Path property; the mask shape matches the transformations tracked in the layer, depending on the type of method that is chosen.

Other considerations when using the mask tracker

  • For effective tracking, the tracked object must maintain the same shape throughout the movie, though the position, scale, and perspective of the tracked object can change.
  • You can select multiple masks before beginning the tracking operation, and keyframes are then added to the Mask Path property for each selected mask.
  • The layer being tracked must be a track matte, an adjustment layer, or a layer with a source that can contain motion. This includes layers based on video footage and precompositions, but not solid-color layers or still images.

The mask tracking analysis searches for content inside the mask. Use the Mask Expansion property to expand or contract the area of the mask.

How to use the Track Mask effect (Learn tutorial)

track mask

Watch this tutorial to learn how to use the Track Mask effect in After Effects to add and shape mask elements that move accurately through your Premiere Pro sequence.

How to use the Mask Tracker (Learn tutorial)

Rigid mask tracker

See this tutorial to learn how to use the mask tracker in After Effects.