Ximagic Photoshop plugins
Home Denoiser Quantizer GrayDither ColorDither Purchase Contact

Ximagic GrayDither toolbox


Ximagic GrayDither is a Photoshop plugin to reduce color/grayscale images to n-level gray using dithering. As a particular case could produce B/W bitmap images (2-level grayscale)


  • Automatic conversion RGB color to grayscale using Y in YCbCr color space
  • 4 threshold dithering methods.
    • 17 Ordered patterns (clustered-dot, dispersed-dot, etc)
    • 5 Ordered calculated patterns.
    • Random
    • User defined
  • 2 error dithering methods.
    • 8 Array patterns (floyd-steinberg, ulichney, fan, jarvis, stucki, sierra).
    • 1 Space filling curve (riemersma)
  • Direct binary search (DBS) dithering.

Support of 8/16 bits images.
Support of Photoshop actions/batch
Support use as Smart filter
Versions for 32 and 64 bit plugin hosts
Mac and Windows versions

Compatible with Paint Shop Pro, The Gimp, IrfanView, XnView, ...

Important: It can produce a bitmap image, but doesn't change the image to bitmap format. If you want to get a bitmap image you should use your image tool to change the image mode, after running Ximagic GrayDither.


Ximagic GrayDither try to include the most known methods of dithering, and allow the user to choose which one to use.

The available Threshold dithering methods are:

  • Dispersed-dot
    • Threshold
    • Checks
    • Diffusion 2x2
    • Diffusion 3x3
    • Diffusion 4x4
    • Diffusion 8x8
  • Clustered-dot
    • Halftone 45° 4x4
    • Halftone 45° 6x6
    • Halftone 45° 8x8
    • Halftone 90° 4x4
    • Halftone 90° 6x6
    • Halftone 90° 8x8
    • Halftone 90° 16x16
  • Random
  • User configurable

The available error dithering methods are:

  • Error Diffusion
    • Floyd-Steinberg
    • Ulichney
    • Fan
    • Jarvis
    • Stucki
    • Sierra3
    • Sierra2
    • Sierra24A
  • Space filling curves
    • Riemersma

Questions, suggestions and bug reports

Comments are welcomed. Please e-mail to support@ximagic.com

Thanks, reused code & copyrights

This application reuses some published color quantization code, without which the work needed to develop it increases several orders of magnitude.
I wish to thanks the Authors or Publishers (in order of appearance)

  • ImageMagick [Ordered Dithering]
  • Thiadmer Riemersma [Riemersma dithering]
  • Libpipi [Direct Binary Search]
  • TinyXML parser

To see the detail of code used and the copyrights go to License