Remove a video background
Key a green screen, or cut the subject out
There are two different jobs here. Footage shot against a green or blue screen is keyed, which is fast and reliable. Footage shot anywhere else has to be rotoscoped, which is harder. Premation has tools for both, and its roto tools are newer and less proven than After Effects' Roto Brush 3.
Free · AGPL-3.0-only · macOS & Windows
The panel that does it
The editor’s own panel, rebuilt on its chrome. It works: drag, toggle, queue.
How to do it
- 01
Green screen: apply Keylight
Keylight is in the Keying folder of the Effects browser; apply it to the footage layer. Pick the screen colour, then tighten the matte with clip black and clip white.
- 02
Clean the edge
Keylight's despill removes the green cast from hair and skin, and choke and matte softness refine the edge. A garbage mask removes stands and corners the key cannot.
- 03
No green screen: Object Matte or Roto Brush
The Track Motion panel has an Object Matte segmenter that turns a subject into a mask. With the Roto Brush, paint over the subject in the Layer panel, Alt-drag over the background, then propagate the matte through the clip.
- 04
Check the matte, then export with alpha
Scrub the whole clip; fix frames where the matte slips. Export as WebM VP9 or ProRes 4444 with Transparent background on to keep the cutout.
Questions
- Is the Roto Brush as good as After Effects'?
- No. Premation's Roto Brush carries a matte with optical flow and is classical rather than neural. On hair, motion blur and fast movement, After Effects' Roto Brush 3 is the safer tool.
- Does background removal send my footage anywhere?
- No. Keying runs on your GPU, and the Object Matte model runs on your machine.
- Can I fill the hole where something was removed?
- There is a Content-Aware Fill for stills and video. It is patch-based rather than generative, so it works best on simple backgrounds.