Rotoscoping (Mask)¶

Description

This filter takes a snapshot of the frame before it draws the Rotoscoping region/mask into the alpha channel. Use it together with the Mask Apply effect, that uses a transition to composite the current frame's image over the snapshot. The typical use case is to add effects in the following sequence:

Rotoscoping Mask (this effect) --> zero or more effects (e.g. Blur, Cartoon) --> Mask Apply

Parameters

Parameter	Value	Description
Mode	Selection	Defines the channel to apply rotoscoping to
Alpha Operation	Selection	Determines how compositing is done
Invert	Switch	Inverts the rotoscoping selection
Feathering width	Integer	Determines the amount of feathering. Default is 0 (no feathering).
Feathering passes	Integer	Sets the number of passes. The more passes the finer and more accurate the feathering will be. Default is 1.

The following selection items are available:

Mode

Alpha	The rotoscoped area will be the alpha channel (default)
Luma
RGB

Alpha Operation

Write on clear	(default)
Maximum
Minimum
Add
Subtract

Notes

See the Rotoscoping effect for more details and examples.