one fing leads . . .
 
 
 

Mosaic Tiles with Limited Colour Set
There are lots of software products about that do mosaic tiling of an image. Mine is slightly different, I think, from any of them for it is looking at simplifying hues and brightness, it’s a bit like pixelate in Photoshop with a limited colour set and with grout between the tiles, so more akin to a real or physical mosaic.
or image url apply
  – see copyright notice
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Grout width px
Grout colour
        RGB: brightness: 26 opacity: 100%
Hue comparison threshold degrees
Brightness comparison threshold %
Tile width and height px
Number of tile colours
Formula for calculating brightness:
 

 
more experiments for the sake of my dreams