Beautiful demo, but I’m not sure it’s accurate to call dithering an “illusion” of more shades than is available?
If you apply a low pass filter to a dithered image, and compare it to a low passed filtered thresholded, you’ll see that the “illusory” shades are really there in the dithered version, they’re just represented differently in the full resolution image.
Similarly, a class D amplifier emits purely off/on pulses before a low pass filter is applied, but no one would call the output an auditory “illusion”. In the case of image dithering, isn’t the low pass filter your own vision + the distance to the screen?
If you apply a low pass filter to a dithered image, and compare it to a low passed filtered thresholded, you’ll see that the “illusory” shades are really there in the dithered version, they’re just represented differently in the full resolution image.
Similarly, a class D amplifier emits purely off/on pulses before a low pass filter is applied, but no one would call the output an auditory “illusion”. In the case of image dithering, isn’t the low pass filter your own vision + the distance to the screen?