Skip to content
ArcBrush ArcBrush Docs

Chroma Key

Node icon
Keyer

Removes a green/blue screen background with spill suppression and matte refinement.

Chroma Key removes a specific color from the image and replaces it with transparency. It’s the standard green-screen / blue-screen removal tool. The similarity control sets how far from the key color counts as background, and the blend control creates a smooth transition at the edges.

Spill Suppression removes color bleed from the key color onto the subject. This is essential when green screen light contaminates hair or skin edges.

Parameters

Section titled “Parameters”

Pins

ImageImage
InputRequired
ImageImage
Output
MatteMask
Output

Keyer

KeyColor (RGBA)
Default: rgba(0, 255, 0, 255)

Key color

SimilarityNumber
Default: 0.25 Range: 0.00–1.00

How far from the key color is still considered background

BlendNumber
Default: 0.15 Range: 0.00–1.00

Transition zone width between keyed and kept pixels

Despill

Spill SuppressionNumber
Default: 0.00 Range: 0.00–1.00

Reduce color bleed from the key color onto the subject

Despill AlgorithmChoice
Default: Legacy Range: Legacy / Robust
  • Legacy: preserves existing Chroma Key spill suppression.
  • Robust: uses the shared Despill algorithm for cleaner channel-neutralization.
Despill BalanceNumber
Default: 0.50 Range: 0.00–1.00
Despill Algorithm = Robust

Which of the two non-key channels the spill is limited toward. 0.5 (center) uses their average. For a green key, 0 favors Red and 1 favors Blue. (Robust despill only.)

Despill ModeChoice
Default: Neutralize Range: Neutralize / Desaturate
Despill Algorithm = Robust
  • Neutralize: reduce the key channel toward the other channels.
  • Desaturate: blend key-dominant pixels toward luminance.

(Robust despill only.)

Mask

Clip BlackNumber
Default: 0.00 Range: 0.00–1.00

Matte values below this clip to fully transparent

Clip WhiteNumber
Default: 1.00 Range: 0.00–1.00

Matte values above this clip to fully opaque

Invert MatteToggle
Default: false

Keep the key color, remove everything else

Usage Tips

Section titled “Usage Tips”
  • Use the eyedropper to pick the exact screen color from the footage.
  • Start with low similarity and increase gradually until the background is cleanly removed.
  • Add spill suppression to remove green/blue fringing on the subject edges.
  • Use Clip Black/White to refine the matte: crush shadows and clip highlights for a cleaner key.
Section titled “Related Nodes”