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by xnxn 2243 days ago
Each of those "greys" are actually dithered 1-bit patterns
1 comments

I think that's just how it's rendered by default - but really the greys are stored at every resolution, so you need 4-bits per pixel.

Plus the app also preserves the difference between 'not drawn' and 'actively drawn in black', so that's another bit needed for 5-bits.

Notice that when you save the image you really get shades of grey and transparent - not dithering.

The greys are stored at every resolution? What do you mean?

The web page states:

16-'color' palette via dither patterns. Each pattern is treated as a separate color for fill tool

However, I suspect this is the bit (no pun intended) you're missing:

save images as a 16-color greyscale (which will import back into Strike with all patterns intact), or as 1-bit black and white image

> The greys are stored at every resolution? What do you mean?

Try it for yourself. Draw one single pixel in one of the middle greys.

Now zoom in.

You can see the dithering pattern now matter how far you zoom in.

How does it know what dithering pattern to keep drawing? There are sixteen to choose from. That requires 4 bits. But we drew just one pixel, so we have just 1 bit of information.

How do you think they're getting 4 bits of information from 1 bit? They can't be - that's impossible. It must be storing the colour you chose for each pixel and then be drawing the dither pattern each time.

> save images as a 16-color greyscale (which will import back into Strike with all patterns intact)

I'm not missing anything. Again - try this as a thought experiment. Draw a single pixel in a mid grey. Export as an image. You'll see a grey colour. How do you think it's recreated that grey from the dither pattern... when the dither 'pattern' is just one single pixel either on or off as that's all we drew? It can't possibly be doing that, can it? That's nonsense. It must be storing each colour per pixel when drawing.

I'm not missing anything

I think you are missing something or perhaps you're interpreting this in a very pedantic fashion.

If you actually use the tool and ask it to export a 1-bit image you'll get a png file. If you zoom in after opening that png file in a editor like Affinity Photo or GIMP, you'll see exactly what the editor describes -- simple pixels that are either black or white.

The argument seems to be that it's not a 1-bit editor because it doesn't have a 1:1 representation between the individual "pixels" in the editor and the output.

However, I would argue it is a 1-bit editor because that's the final output -- a 1-bit image.

The fact that it maps each of the 16 'colors' to a 1-bit dithering pattern seems like an innovative way to provide 1-bit results.

Weird. Better to screenshot than