Matte Control Node

Matte Control does three things:

1. Combines two mattes (an alpha from the Foreground into the Background) with 10 available operations.
2. Refines the resulting alpha (blur, contract/expand, gamma, threshold, invert).
3. Removes spill (green/blue reflections on the subject) with the same controls as the keyers.

Placed downstream of a keyer (Chroma, Delta, Primatte), it cleans the matte and applies spill suppression in a single node - instead of chaining several specialized nodes.

• Effects Library: Tools > Matte > Matte Control
• Quick add: right-click in the Node Editor → Add Tool > Matte > Matte Control

• Background (orange) - required. Receives the Foreground alpha after processing.
• Foreground (green) - optional. The source of the alpha to apply to the Background.
• Garbage Matte (gray) - optional. Areas made transparent.
• Solid Matte (white) - optional. Areas forced to opaque.
• Effect Mask (blue) - optional.

MediaIn → Delta Keyer → Matte Control → Merge 2D → Saver
                                   ↑
                        (refinement + spill supp)

The Matte Control node takes the Delta Keyer alpha downstream, refines it and removes the remaining spill. It lets you keep the Delta Keyer simple and do the cleanup separately.

Sets how the Foreground alpha is combined with the Background alpha:

Copy

Fully replaces the Background alpha with the Foreground alpha. The most common.

Add / Subtract

Adds or subtracts the alpha values. Add = union (everything that is opaque in one OR the other).

Inverse Subtract

Reversed subtraction (Background − Foreground instead of FG − BG).

Maximum / Minimum

Keeps the larger or smaller value per pixel. Max = union, Min = intersection.

And / Or

Logical operations. And = strict intersection, Or = strict union.

Merge Over / Merge Under

Merges the alpha over or under. Useful to add a matte without overwriting the existing one.

Blur + Filter

Softens the edges of the alpha. Algorithms: Box, Bartlett, Multi-Box, Gaussian.

Contract / Expand

Shrinks or grows the matte boundary. The classic: a light Contract + a light Blur = softened edges that do not bleed onto the subject.

Gamma

Adjusts the semi-transparent areas (gray values of the matte). Does not touch pure black or white areas.

Threshold

Creates a binary transition (pixels become either fully transparent or fully opaque). Useful for a "clean" matte with no gray.

Invert Matte

Inverts the transparency. Opaque becomes transparent and vice versa.

The same spill suppression controls as the Delta Keyer, but in a separate node. Handy for a modular setup.

• Spill Color - picks the color to remove (usually green or blue).
• Method - Rare, Medium, Well Done, Burnt (same scale as the keyers).
• Fringe adjustment - Cyan/Red, Magenta/Green, Yellow/Blue sliders to color correct the semi-transparent pixels.

• Post-keyer cleanup - use case #1. A Matte Control after a Delta Keyer to refine the edges, remove spill and reduce fringing.
• Combining two mattes - two different keyers on the same shot (e.g. a hard key + a soft key for hair) → a Matte Control in Max mode to merge them.
• Cleaning an external matte - a hand-painted matte or one imported from another app: a Matte Control for blur + contract before using it.
• Subtracting one matte from another - Subtract mode to remove an area from an existing matte (e.g. cutting the mouth out of a face mask).
• Extra spill suppression - if the primary keyer did not fully remove the spill, add a Matte Control with Spill Method Well Done or Burnt.
• Binarizing a gray matte - push Threshold to the max to get a 100% binary matte (no semi-transparency). Useful for IDs and strict selections.

• Small Contract + small Blur combo - the "pro" finish for every matte. Shrink first so it does not bleed, then soften to avoid hard edges.
• Simpler than stacking specialized nodes - a single Matte Control often replaces: Matte Blur + Erode/Dilate + Spill Suppress. Fewer nodes in the graph.
• Invert to create a hole - Invert Matte ticked on a painted mask = a "hole" in the Background (e.g. masking an area to reveal an element behind it).
• View the alpha while you work - turn on the viewer's alpha mode to see exactly what each slider changes on the matte.
• Max / Min for union / intersection - Max adds the mattes together (union), Min intersects them (shared areas only).
• For a big keying workflow, several Matte Control nodes in a chain let you split the steps: one for cleanup, one for spill, one for combining. Clean and modular.