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Bypassing Anti-aliasing

Summary

Bypassing Anti-aliasing (Last Updated: December 12th, 2006)

This tip describes a simple method for bypassing Fusion's anti-aliasing to produce a mask with jagged edges. This technique would also work with creator tools like Text.

Description

There are occasionally times when one wants to generate a mask without anti-aliasing. However, there is no way in Fusion to turn anti-aliasing of edges off on a specific tool. One trick is to use a Bitmap Mask tool to crush the semi-transparent portions of the mask up to fully opaque. This tip assumes there are no semi-transparent portions of the mask which need to be preserved.

Fusion 5.0

1. Add an ellipse mask to a composition
2. Connect the output of the ellipse mask to a new Background tool.
3. Connect the Background to a new Bitmap Mask tool
4. Set the Bitmap Mask tools Low value to 1.0 and the High to 1.0 as well.

Fusion 5.1

Since Fusion 5.1 allows masks to be connected directly to image input, it is possible to skip a step.

1. Add an ellipse mask to a composition
2. Connect the output of the ellipse mask to the image input of a new Bitmap Mask tool
3. Set the Bitmap Mask tools Low value to 1.0 and the High to 1.0 as well.