Undithering images in Tom's Editor
Undither filter is available under Noise.
This filter can remove regular dither from images. This kind of dither was very popular in old games.
If your photo was dithered using non-regular dithering algorithms, such as Floyd-Steinberg or Stucki, then this filter won't work well.
Undither does not smooth images.
Original image
After Undither
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