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Ditherpunk: The article I wish I had about monochrome image dithering

surma.dev

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Re: Ditherpunk: The article I wish I had about monochrome image dithering

#5

Post by dljsjr »

> According to Wikipedia, “Dither is an intentionally applied form of noise used to randomize quantization error”, and is a technique not only limited to images. It is actually a technique used to this day on audio recordings […]

Dithering as a digital signal processing technique is also used frequently in the digital control of physical systems. One example of this is in the control of hydraulic servo valves[1]; these valves are usually pretty small and their performance can be dominated by a lot of external factors. One of the biggest ones is "stiction", or static friction, wherein if the moving parts of the valve are at rest it can take a large amount of current to get them going again which translates in to poor control of the valve and in turn poor control of the thing the valve is trying to move. It's common to use very high frequency/small amplitude dithering on these valves to eliminate the effects of stiction without compromising accuracy which greatly improves the control stability and responsiveness of the servo valves.

1: https://en.wikipedia.org/wiki/Electrohydraulic_servo_valve

Re: Ditherpunk: The article I wish I had about monochrome image dithering

#6

Post by jstrieb »

This article is very well put together, and a helpful reference, thanks for sharing!

A sibling comment links to a Show HN that didn't get much attention, but is definitely worth checking out. I will also point out that it is possible to do dithering using GIMP (https://docs.gimp.org/en/gimp-image-convert-indexed.html). Alternatively, use ImageMagick if that is more your speed (https://legacy.imagemagick.org/Usage/quantize/#ordered-dithe...)

Re: Ditherpunk: The article I wish I had about monochrome image dithering

#9

Post by gruez »

amelius wrote: post #8

How would you apply dithering to animations (without the screen looking noisy from the different starting conditions of each frame)?

discussed by the author of the mentioned game (return of the obra dinn) here: https://forums.tigsource.com/index.php?topic=40832.msg136374...
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