Re: Double hires mode color artifacts

["Michael J. Mahon" <mjmahon@aol.com>]

vladitx wrote:
> On Sep 6, 12:10 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
>
> > I've suggested a very simple table-driven algorithm that should do
> > quite well.
>
>
> I'm actually waiting for someone to derive such a look-up table, so I
> can incorporate it in the RA2 emulator. The framework is all there -
> 14MHz scanlines and sliding window to derive host framebuffer pixel.
> 14 bits is fully ok with me - I will happily sacrifice CPU cycles to
> fidelity.
>
> Additional "apple2" screensaver effects of a real TV set are not
> needed. Just the limited bandwidth of luma and chroma signals with
> phase offsets considered.

I presume that in the meantime you've tested with a table that simply
contains the unfiltered values (without sharp transitions)?  Such a
table will have large blocks of identical entries equal to Linards'
derived RGB values.

Of course, it won't emulate NTSC transitions, but it will demonstrate
the exact performance achieved.

-michael

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