Effects / Dither

Atkinson

Atkinson dithering was developed by Bill Atkinson for the original Apple Macintosh. It only diffuses 6/8 of the error (not 8/8), creating a lighter, more "open" appearance that's become iconic in retro computing aesthetics.

dither-atkinsonFree

Effect ID: dither-atkinson

Example Configuration

atkinson.json

{
  "effectId": "dither-atkinson",
  "dither": {
    "pattern": "atkinson",
    "pixelation": 4,
    "paletteId": "monochrome",
    "colors": ["#000000", "#ffffff"],
    "brightness": 1,
    "contrast": 1,
    "threshold": 0.5
  }
}

Settings

Property	Type	Default	Description
`pattern`	string	"atkinson"	Dither pattern algorithm
`pixelation`	number	4	Point size (1-10)
`paletteId`	string	"monochrome"	Color palette ID
`colors`	string[]	["#000", "#fff"]	Color array (dark to light)
`brightness`	number	1	Brightness adjustment (0.5-2)
`contrast`	number	1	Contrast adjustment (0.5-2)
`threshold`	number	0.5	Error diffusion strength (0-1)

How It Works

Atkinson spreads the quantization error differently from Floyd-Steinberg:

      X   1/8  1/8
1/8  1/8  1/8
     1/8

Key differences from Floyd-Steinberg:

Only 6/8 (75%) of the error is diffused, not 100%
Error spreads further (2 rows) but more evenly
Results in brighter images with more "white space"
Creates the classic Mac halftone look

Comparison with Floyd-Steinberg

Aspect	Atkinson	Floyd-Steinberg
Error diffused	75%	100%
Spread area	6 pixels	4 pixels
Appearance	Lighter, more open	Darker, denser
Best for	Portraits, illustrations	Detailed photos

API Usage

render-request.json

POST /api/v1/render
{
  "state": {
    "canvas": {
      "aspectRatio": "16:9",
      "backgroundColor": "#1a1a1a"
    },
    "layers": [...],
    "selectedLayerId": null,
    "effect": {
      "effectId": "dither-atkinson",
      "enabled": true,
      "dither": {
        "pattern": "atkinson",
        "pixelation": 4,
        "paletteId": "monochrome",
        "colors": ["#000000", "#ffffff"],
        "brightness": 1,
        "contrast": 1,
        "threshold": 0.5
      }
    }
  },
  "format": "png",
  "width": 1920,
  "height": 1080
}

Tips

Iconic for creating the "classic Mac" aesthetic
Works beautifully with portraits and faces
Reduce brightness slightly for images that come out too light
Perfect for creating retro 1-bit art