edges mask
The frame’s own outlines. A Sobel pass finds every contour and rim, so an effect can ride only the lines — the drawing under the picture.
What it’s for
An ink-and-paint artist sees a frame as two things: the flats and the lines. The edges mask gives you the lines. A Sobel gradient runs over the source and wherever the image changes fast — a contour, a rim light, a hard shadow boundary — the mask goes to 1. Everywhere flat, it stays at 0.
low suppresses the weak edges so film grain and
compression noise don’t register as structure.
high saturates the strong ones so a defined
contour reads as solid line, not a faint trace.
gamma tunes the gradient in between — a
fine pencil or a heavy marker.
Reach for this when: you want chromatic aberration on contours only; a glow that clings to rim lighting; an outline-ink overlay that turns footage into a moving line drawing.
Where it lives in the app
Add from the Masks panel. The mask appears as its own layer
on the timeline; assign it to one or more effects by setting
their target to point at this mask layer.
Parameters
| Key | Range | Default | Effect |
|---|---|---|---|
low | 0–1 | 0.05 | Suppress weak edges |
high | 0–1 | 0.4 | Saturate strong edges |
gamma | 0.1–4 | 1 | Curve |
Pairs well with
- chromatic aberration — colour fringing on contours only. Everything reads sharp until your eye lands on an edge that won’t hold still.
- phosphor CRT glow — rim lighting that blooms like a hot filament tracing the subject.
- text-glitch — letterforms whose outlines fray while their interiors stay calm. A drawing coming undone at the seams.
- color grade — a contour tint that turns the whole frame into an inked cel.