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Re: Supercard



Linards Ticmanis wrote:
Michael J. Mahon wrote:


Of course, an NTSC processor doesn't care about boundaries, only about
streams of bits--which I why I proposed a shift register "window" that
is more than 4-bits wide, like 8 or 12, even, for greater fidelity to
analog color processing.


Interesting approach. How would the forumlae for determining one output
pixel's color work in this case? In principle, I mean.

You would do it just as you have done in the past, but with a wider
"window" and a lowpass filter applied to the chroma before demodulation.
That "smears" the color out.   Of course, the delay of the lowpass must
be matched in the luminance channel to keep things in register.

The width of the window is the only limit on the "context dependency"
of a pixel's appearance.

This would amount to a "canonical" analog NTSC simulation for inputs
that are binary strings at 14MHz.

The computed R, G, and B values for, say, 12-bit substrings could then
be stored in RAM and indexed by the "shift register" for output to
the DACs.

-michael

Parallel computing for 8-bit Apple II's!
Home page:  http://members.aol.com/MJMahon/

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