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anonfunction

I was showing coworkers an example of the Floyd Steinberg algorithm today.

The following images have the same amount of colors, namely black and white.

https://i.imgur.com/stQUl5E.gif

https://i.imgur.com/mw8IX9N.gif

Source image:

https://i.imgur.com/diR72k2.jpg

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My suspicion is that you didn't handle the gamma correctly as mentioned in another comment.

Indeed, the dithered image looks way too bright. It should be converted from sRGB gamma to linear light before dithering to black/white. Also, will need more than 8bits per channel if you hold the linear image as an intermediate result, otherwise you get posterization in the dark areas before the dithering even starts.

https://imgur.com/595mX6m

Done with imageworsener[1].

    imagew -cc 2 -dither f -grayscale diR72k2.jpg diR72k2_dither.png

[1] http://entropymine.com/imageworsener/

Is there any way to get the imgur mobile site to load the full res version?

On Safari for iOS, long-press the reload icon in URL bar and choose “Request Desktop Site”.

You’ll get a diff layout that shows the GIF.

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