Adobe After Effects User Manual
Page 390
Roto Brush, Refine Edge, and Refine Matte effects | CC
Roto Brush & Refine Edge tools
Roto Brush & Refine Edge workflow
Freezing (caching, locking, and saving) Roto Brush segmentation
Layer panel view options
Refine Hard Matte and Refine Soft Matte effects
Roto Brush & Refine Edge, Refine Hard Matte, and Refine Soft Matte effect reference
Separating a foreground object, such as an actor, from a background is a crucial step in many visual effects and compositing workflows. When
you’ve created a matte that isolates an object, you can replace the background, selectively apply effects to the foreground, and much more.
Roto Brush & Refine Edge tools
The Roto Brush tool and the Refine Edge tool provide an alternative, faster workflow for segmentation and creation of a matte.
A. Roto Brush B. Refine Edge
Roto Brush
Use this tool to create the initial matte to separate an object from its background. With the Roto Brush tool, you draw strokes on representative
areas of the foreground and background elements. Then After Effects uses that information to create a segmentation boundary between the
foreground and background elements. The strokes that you make on one area inform After Effects about what is foreground and what is
background on adjacent frames. Various techniques are used to track regions across time, and this information is used to propagate segmentation
forward and backward in time. Each stroke that you make is used to improve the results on nearby frames. Even if an object moves or changes
shape from one frame to the next, the segmentation boundary adapts to match the object.
Refine Edge tool
Use the Refine Edge tool to improve the existing matte by creating partial transparency along areas that contain fine details such as hair or fur.
Roto Brush & Refine Edge effect
This effect is applied automatically when the first Roto Brush or Refine Edge stroke is drawn in the layer panel. Use this effect to control the
settings for the Roto Brush & Refine Edge tools. After you have created a segmentation boundary and the boundary edges that need refining, use
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