Sr. Developer @easytechgreen

Week of the 25/01/2021 - #4



  • CMYK, Dithering and Halftoning

CMYK, Dithering and Halftoning

Lately I’ve been creating some collages using pieces of paper collected from street publicity. These images use CMYK printing which yields some beautiful patterns when viewed up close. Here are some sample images I’ve created:

Cromatic Collage 1 / 14Jan21 Cromatic Collage 2 / 14Jan21

Some links related to the graffic techniques used:

  • CMYK color model - “The CMYK color model (also known as process color, or four color) is a subtractive color model, based on the CMY color model, used in color printing, and is also used to describe the printing process itself. CMYK refers to the four ink plates used in some color printing: cyan, magenta, yellow, and key (black).”

How colors are generated:

Halft-toning color (WikiPedia)

Patterns arise from angles of halftoning marks:

CMYK Screem Angles (WikiPedia)

  • Halftone - “is the reprographic technique that simulates continuous-tone imagery through the use of dots, varying either in size or in spacing, thus generating a gradient-like effect.[1] “Halftone” can also be used to refer specifically to the image that is produced by this process”
  • Dithering - “Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and video data, and is often one of the last stages of mastering audio to a CD.”
  • Simple gradient-based error-diffusion method, Xiangyu Y.Hu, Journal of Electronic Imaging 25(4), 043029 (Jul∕Aug 2016). Paper with some popular dithering techniques.
  • Image dithering in Matlab, Wayback machine link

Idea 💡

Create a 3D shader that reproduces this patterns when viewd from afar.