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Gradient Map

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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.

Parameters

Section titled “Parameters”

Color

Source ChannelChoice
Default: Luminance

Lookup source

  • 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.
Preserve AlphaToggle
Default: true

Keep original alpha; uncheck to also map alpha

Mask

Mask FitChoice
Default: None

Mask sizing

  • NoneCenter 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.
  • FitScale the mask to fit inside the image, preserving aspect ratio. Letterboxes where needed.
  • FillScale the mask to fill the image, preserving aspect ratio. Crops edges if aspect ratios differ.
Notes

Mask Fit only visible when mask is connected.

Pins: image (required), mask (optional). When mask is connected, the effect is blended with the original using the mask (white = full effect, black = original).

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.
  • Preserve Alpha to keep the original transparency when colorizing.
  • Connect a mask input to apply the color mapping to only part of the image.
  • Each stop in the gradient editor has its own eyedropper for sampling colors directly from the canvas.
Section titled “Related Nodes”