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Dither

dither

Quantizes an image to a palette with ordered or error-diffusion dithering

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The node name and summary are available in English. Port, parameter, and article details are currently shown in Japanese.

Input Ports

NameTypeDescription
画像
input
Image
Required
ディザリングしたい画像です
パレット
palette
Palette
任意のパレット入力です。未接続なら画像からパレットを抽出します

Output Ports

NameTypeDescription
画像
output
Image
ディザリング後の画像です
パレット
palette
Palette
ディザリングに使ったパレットです

Parameters

NameTypeDefaultRangeDescription / Options
ディザ方式
mode
Enum
Ordered4x4

どのディザ方式を使うかです

  • 順序 4x4Ordered4x4
    4x4 の Bayer 行列で、規則的な順序ディザをかけます。
  • 誤差拡散FloydSteinberg
    Floyd-Steinberg の誤差拡散ディザをかけます。
抽出モード
extract_mode
Enum
Representative

パレット入力がない時に、画像からどうパレットを作るかです

  • 実色抽出Exact
  • 代表色抽出Representative
最大色数
max_colors
Int
161–256

抽出時に残す最大色数です

透明色をパレット抽出に含める
include_transparent
Bool
false

パレット抽出時に完全透明ピクセルも含めます

透明ピクセルも加工する
process_transparent_pixels
Bool
false

完全透明ピクセルの非表示RGBもディザリング・減色します

元の透明度を保つ
preserve_alpha
Bool
true

色を変えても、元画像の透明度はそのまま残します

強さ
strength
Float
10–2 / step 0.01

ディザ模様をどれくらい強く出すかです

Overview

Quantizes to a palette while applying a dither pattern that represents intermediate tones with few colors. It is essential for reducing gradients to a 2–16-color texture that reads as retro pixel art.

Usage tips

  • Choose the method by look: orderly checkerboard retro texture → Ordered4x4; natural, photographic grain → FloydSteinberg. Ordered often feels more deliberately pixel-placed and fits pixel-art assets better.
  • Connecting a palette is the standard setup. Connect the project palette to keep the asset within the overall color system. When unconnected, colors are extracted automatically from the image, with the count controlled by max_colors.
  • strength controls the visibility of the pattern in both modes. 1 is standard; 0.3–0.7 gives a subtle pattern, 2 creates a strongly gritty texture, and 0 performs palette quantization without adding ordered offsets or diffusing quantization error.
  • include_transparent affects automatic palette extraction only. process_transparent_pixels separately controls whether hidden RGB in fully transparent pixels is quantized. Both should normally stay OFF.
  • Gradient → dither with a 2–4-color palette quickly creates retro skies, glows, and water.

Common pitfalls

  • No pattern appears: dithering has no effect when the input has no intermediate tones and already matches the palette exactly. Use it on continuous-tone gradients or noise.
  • Colors look muddy or unexpected colors appear: automatic extraction with Representative creates average representative colors. Connect a palette or use extract_mode = Exact when only specified colors are allowed.
  • Transparent areas look wrong: preserve_alpha (ON by default) retains source transparency. Enable include_transparent only to include transparent colors in an extracted palette, and enable process_transparent_pixels only when their hidden RGB should also be modified.

Notes

  • 誤差拡散 tends to preserve local contrast; 順序 4x4 is regular and easy to control.
  • When a palette input is connected, that palette is used as-is.
  • _count is the number of palette colors actually used.

Examples

  1. Reduce to the color count produced by Palette Extract.
  2. Create a retro screen pattern with a two-color black-and-white palette.
  3. Produce a more visibly patterned quantization than Palette Quantize.

Related nodes

  • palette_quantize — simple quantization without dithering for flat results
  • palette_extract — extract the quantization palette from an image
  • gradient_generate / noise_generate — create continuous tones that show dithering well
  • posterize — reduce tonal steps by count rather than by palette
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Dither — PixPipeline Node Reference