The first time I heard the term "dithering" it was on my Amiga. They were referring to this kind of temporal dithering, not the kind of we all think about now. The point back then was to display more than 4096 colors on the screen at once. I believe the loaded up 2 hardware screen buffers with the 2 images and then page flipped back and forth as fast as possible.
I don't remember there being as much flicker, but since the goal was to get more subtle colors the images were probably much closer to each other than this demo.
The Amiga used HAM (Hold And Modify) to show 4096 colors. Not dithering.
IIRC HAM was similar to delta encoding where the difference was stored pixel to pixel rather than the absolute RGB used just 5 bits.
If you flick between two images at 25Hz then you'll sort-of get more colours. I think Quantum Paint on the Atari ST did this, to get more than 512 colours on screen (at the cost of the thing looking like a flickering mess), or maybe it's some other package I'm thinking of.
I didn't realise anybody ever bothered to do this on the Amiga - 4096 colours used to be enough for anybody - but of course there's no reason why you couldn't. The effect would probably only be improved with colours that are closer together.
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The first time I heard the term "dithering" it was on my Amiga. They were referring to this kind of temporal dithering, not the kind of we all think about now. The point back then was to display more than 4096 colors on the screen at once. I believe the loaded up 2 hardware screen buffers with the 2 images and then page flipped back and forth as fast as possible.
I don't remember there being as much flicker, but since the goal was to get more subtle colors the images were probably much closer to each other than this demo.
The Amiga used HAM (Hold And Modify) to show 4096 colors. Not dithering. IIRC HAM was similar to delta encoding where the difference was stored pixel to pixel rather than the absolute RGB used just 5 bits.
If you flick between two images at 25Hz then you'll sort-of get more colours. I think Quantum Paint on the Atari ST did this, to get more than 512 colours on screen (at the cost of the thing looking like a flickering mess), or maybe it's some other package I'm thinking of.
I didn't realise anybody ever bothered to do this on the Amiga - 4096 colours used to be enough for anybody - but of course there's no reason why you couldn't. The effect would probably only be improved with colours that are closer together.
Yup, HAM was a weird encoding that was mostly good for still images, though I remember there was a game that made a big deal about using the HAM mode.
However, I said "more than 4096 colors"...