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Gradient Map

Node icon
Color

Maps luminance values to a color gradient, turning any grayscale range into a color palette.

Gradient Map replaces brightness values with colors from a gradient. Dark areas of the image map to the left side of the gradient, bright areas to the right. This is a powerful way to colorize grayscale images, create duotone effects, or apply stylized color schemes.

The source channel selector lets you map from Luminance, or from any individual R/G/B/Alpha channel. The same seven Interpolation modes (RGB, Linear sRGB, OKLab, OKLCh, HSV, Kubelka-Munk, Constant) and Hue Path control as the Gradient node decide how colors blend between stops, so you can design perceptually smooth ramps or pigment-mixing palettes without dropping extra stops.

The Alpha dropdown decides how the gradient’s alpha interacts with the source image: Preserve keeps the source alpha unchanged (the gradient’s alpha is ignored), Multiply (default for new nodes) multiplies source alpha by gradient alpha so transparent stops cut through, and Replace lets the gradient’s alpha overwrite the source entirely. Saved projects from earlier versions auto-migrate so existing graphs render the same as before.

Parameters

Section titled “Parameters”

Pins

ImageImage
InputRequired
MaskMask
InputOptional
ImageImage
Output

Gradient

Stop CountInteger
Default: 2 Range: 2–16

Number of stops; additional s2..sN are injected dynamically

Stop 0 PositionNumber
Default: 0.00 Range: 0.00–1.00

Stop 0 normalized position

Stop 0Color (RGBA)
Default: rgba(0, 0, 0, 255)

Stop 0

Stop 1 PositionNumber
Default: 1.00 Range: 0.00–1.00

Stop 1 normalized position

Stop 1Color (RGBA)
Default: rgba(255, 255, 255, 255)

Stop 1

Color Mapping

Source ChannelChoice
Default: Luminance

Which channel drives the gradient lookup

  • LuminanceMap based on perceived brightness — the most natural choice.
  • RedMap based on the red channel value only.
  • GreenMap based on the green channel value only.
  • BlueMap based on the blue channel value only.
  • AlphaMap based on the alpha (transparency) value.
AlphaChoice
Default: Multiply

How the gradient's alpha combines with the source alpha

  • PreserveKeep the source image's alpha unchanged. The gradient's alpha is ignored.
  • MultiplyDefault for new nodes. Source alpha is multiplied by gradient alpha, so transparent stops cut through.
  • ReplaceThe gradient's alpha overwrites the source image's alpha entirely.
InterpolationChoice
Default: RGB

Color space used to blend between gradient stops

  • RGBDefault. Blends red, green, and blue channels directly. Fast and predictable.
  • Linear sRGBBlends in linear-light space, which keeps midpoints from looking dim.
  • OKLabPerceptually smooth blends without the muddy midpoints you can get from blending two contrasting colors in RGB.
  • OKLChLike OKLab but preserves chroma through the midpoint, so vivid contrasting hues stay vivid through the middle.
  • HSVSweeps through the hue wheel for vivid color transitions.
  • Kubelka-MunkPigment-mixing model where blends behave like real paint rather than light.
  • ConstantHolds each stop's color until the next stop, for stepped gradients with no blending.

Mask

Mask FitChoice
Default: None (native size)
Mask connected

How the mask is sized when it doesn't match the image. None: center at native size, no scaling. Stretch: scale to exactly match image dimensions. Fit: scale to fit inside image, preserving aspect ratio. Fill: scale to fill image, cropping overflow

  • None (native size)Center the mask at its native size — no resizing. Unmasked regions are unaffected.
  • StretchStretch the mask to exactly match the image dimensions. May distort the mask shape.
  • Fit (letterbox)Scale the mask to fit inside the image, preserving aspect ratio. Letterboxes where needed.
  • Fill (crop)Scale the mask to fill the image, preserving aspect ratio. Crops edges if aspect ratios differ.

Usage Tips

Section titled “Usage Tips”
  • Use a two-stop gradient (dark color → light color) for a classic duotone effect.
  • Wire Noise output into Gradient Map to create colorized procedural textures.
  • Set Alpha to Preserve to keep the source’s original transparency unchanged when colorizing; choose Multiply when you want transparent gradient stops to cut through the result.
  • Pick OKLCh or OKLab interpolation for smoother midtones between contrasting colors, especially in duotone work.
  • Connect a mask input to apply the color mapping to only part of the image.
  • Each stop in the gradient editor has its own Pick Color button for sampling colors from anywhere on screen.
Section titled “Related Nodes”