Reducing Colors

Color reduction turns a full image into a smaller palette that can become printable layers. This is the main 2D preparation step.

Adjustments First

Use Adjustments to make the subject easier to separate before reducing colors. The controls are:

ControlUse it for
ExposureOverall brightness.
ContrastStronger or softer separation between tones.
Highlights and ShadowsRecovering detail in bright or dark regions.
Whites and BlacksMoving the brightest and darkest endpoints.
Saturation and VibranceMore or less color intensity.
Hue, Temperature, and TintCorrecting color shifts.
ClarityLocal contrast and edge definition.

Click Apply in the Adjustments panel to bake the current look into the image.

Quantization Settings

Use Quantization Settings to reduce the image.

  • Palette chooses the target color set. Auto lets Kromacut find colors from the image. Built-in palettes and custom palettes constrain the result to known colors.
  • Number of Colors sets the target color count when using Auto.
  • Algorithm Weight changes how strongly the selected algorithm groups colors. It is disabled when the algorithm is None (postprocess only).
  • Algorithm chooses the reduction method.
  • Apply runs the reduction.

Choosing An Algorithm

AlgorithmWhen to try it
None (postprocess only)You already have the colors you want and only need palette postprocessing.
PosterizeSimple graphic images with broad color regions.
Median-cutFast general-purpose reduction.
K-meansA good default for photos and mixed artwork.
WuSmooth photos or gradients that need balanced color buckets.
OctreeImages with many distinct colors and sharp regions.

If the result looks muddy, try fewer colors plus stronger contrast. If important colors disappear, increase Number of Colors or try another algorithm.

Custom Palettes

The palette toolbar lets you create, edit, import, export, or delete custom palettes.

  • Custom palettes can be saved for later use.
  • Palette files use the .kpal format.
  • Pick colors that match real filament when you plan to use Manual mode.

Image Colors

The Image colors panel shows detected swatches. The count excludes fully transparent pixels.

Click a swatch to open Edit Color. You can:

  1. Change the color with the picker.
  2. Type a hex value.
  3. Adjust transparency.
  4. Click Apply to replace the swatch in the image.
  5. Click Delete to remove that color from the image.

Tip: Keep Manual-mode palettes small. If the image has more than 64 colors, Kromacut disables swap instructions and asks you to reduce the image first.

Next: Dedithering and cleanup.