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Cell block noise filter and other effects - Printable Version

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+--- Thread: Cell block noise filter and other effects (/Thread-Cell-block-noise-filter-and-other-effects)

Cell block noise filter and other effects - grit - 08-03-2017

Is there a filter in GIMP to generate this:

[Image: render_blender-render_textures_procedura...-noise.jpg]

RE: Cell block noise filter and other effects - rich2005 - 08-03-2017

Not directly

First thoughts:

1. Render some solid noise Filters -> Render -> Clouds -> Solid Noise screenshot: http://i.imgur.com/RbjLuxE.jpg

2. You might have to tweak the brightness http://i.imgur.com/a9D8PQQ.jpg

3. Filters -> Blur -> Pixelise

[Image: htpUb41.jpg]

RE: Cell block noise filter and other effects - Ofnuts - 08-04-2017

Another method:
  • Start with a small image (you will blow it up by the size of your squares to if you need 16x16 squares in a 800x800 image, start with a 50x50 image/layer).
  • Fill 50% gray HSV=0,0,50% or RGB=127,127,127
  • Filter>Noise>HSV noise: Hue=0, Saturation=0, Value=128, Holdness=1. If you have all of this right, Windows>Dockable dialog>Histogram should show a horizontal (but jagged) line, indicating an equal spread of the grays.
  • Image>Scale image (or Layer>Scale layer): Size=1600%, interpolation=None

[attachment=655]

RE: Cell block noise filter and other effects - grit - 08-06-2017

Is it possbile to make random sized rectangles ?

RE: Cell block noise filter and other effects - rich2005 - 08-06-2017

You come up with some interesting questions.

No solution but this might be a starting point. The G'mic blockism filter

http://i.imgur.com/xdHuQxW.jpg

And steps leading to that, noise -> posterise -> gmic

http://i.imgur.com/6gmfoez.jpg

Hopefully, someone will come up with more suggestions.

RE: Cell block noise filter and other effects - Ofnuts - 08-06-2017

(08-03-2017, 11:58 AM)rich2005 Wrote: Not directly

First thoughts:

1. Render some solid noise Filters -> Render -> Clouds -> Solid Noise screenshot: http://i.imgur.com/RbjLuxE.jpg

2. You might have to tweak the brightness http://i.imgur.com/a9D8PQQ.jpg

3. Filters -> Blur -> Pixelise

Second thoughts:

  1. The Solid Noise histogram is not spread evenly over all the range of values, so even if you use Levels or Brightness/Contrast to extend the range, you still have more gray than anything else
  2. The larger the squares in Colors>Pixellize, the more you average values, and the more your squares end up gravitating around 50% gray. This problem would show up whatever the initial noise rendering technique. So at that point you need a second shot of brightness/contrast to re-extend the range of values.


RE: Cell block noise filter and other effects - grit - 08-06-2017

(08-06-2017, 12:19 PM)rich2005 Wrote: You come up with some interesting questions.

No solution but this might be a starting point. The G'mic blockism filter

http://i.imgur.com/xdHuQxW.jpg

And steps leading to that, noise -> posterise -> gmic

http://i.imgur.com/6gmfoez.jpg

Under noise filter I don't have posterize and I don't have blockism in G'Mic. Where did you find it ?

RE: Cell block noise filter and other effects - rich2005 - 08-06-2017

Posterise is in the colors menu: http://i.imgur.com/r5kDdr2.jpg

You have the QT vesion of g'mic. I saw your post on GC, you got G'mic installed but you need to update the filters.
Enable Internet, click on the update icon.

[Image: 5TDsz6D.jpg]

The search does work. (As a note there is a Gimp standard blockism filter which is very different.)

gmic screenshot: http://i.imgur.com/khCSPP9.jpg

RE: Cell block noise filter and other effects - grit - 08-06-2017

Thanks. I have version 2.02 installed.

RE: Cell block noise filter and other effects - rich2005 - 08-07-2017

(08-06-2017, 04:15 PM)grit Wrote: Thanks. I have version 2.02 installed.

That was updating the filters not the G'mic version. Should always do a refresh after installation and if you keep the internet unchecked, enable it and update now-and-again.

A-new-day and playing with that gmic blockism filter. Some interesting patterns possible.

This one starting with a radial colour gradient, with sawtooth repetition, interesting colourful pattern, which can desaturate if grey needed. http://i.imgur.com/rcfejQ9.jpg