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Old 23 April 2015, 13:13   #40
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Originally Posted by jsr View Post
Dither and higher resolution cannot solve a big "hole" (or a bunch of small holes) on the screen.
It can as averaging (related to limited bandwidth) can't be ignored - this is main principle of dithering and noise shaping - thanks to this we have single bit high-end (32 bit) audio converters.
single bit ZD can be translated in genlock electronic to intermediate steps (analog) transparency even with hardswitching genlocks (as they have limited bandwidth/slew rate of switching) and even if they have bandwidth more than 7MHz still there is plenty of other bandlimiting filters (and there is temporal dithering available as option).

Originally Posted by jsr View Post
And what do you think of the results? Just because i think the spatial one may have stronger and sharper colours (actually too sharp and strong i think, it's garish), but it is extremely noisy compared to the Wu. I believe you use a high resolution flat monitor, so you don't see it from near; on my 1024x768 CRT it's very noisy.
Once again dither (and noise shaping) are very important - to verify result (perceived) Amiga (real one) connected to bandlimited display (such as 1084) probably will be significantly better - in real life (especially in CRT) such signal will be averaged and will produce better quality - don't ignore limited bandwidth available at analog Amiga output (VIDIOT or Video DAC is very crude in Amiga - few resistors and transistor).

Personally i don't care about noise when it provide better psychovisual effect. I was just curious about how Wu will perform against color spatial (as Your observations was contradictory to mine).
SCQ perform obviously better than Wu (15 colors provide picture closer to original) and with typical bandwidth for SCART input in regular TV (around 5 - 6MHz maximum) should provide better visual results thanks to averaging.
Algorithms like Wu provide good results with relatively high number of colors in CLUT (probably somewhere around 64 - 128 colors at least).
And my comment about displays - modern LCD have significantly higher Kell factor and as such they NOT blurring video as CRT's (of course you can always resize video 2 or 4 times with point resampling and introduce some Gaussian blur to simulate CRT) they usually provide worse results than CRT's and TV in such extreme cases (low CLUT size).

Last edited by pandy71; 23 April 2015 at 13:18.
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