GSport: Video Overlay Card?

Brandon Taylor

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Sep 4, 2015, 5:24:45 PM9/4/15

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How much work would it be to implement emulation into GSport of an Apple IIgs Video Overlay Card, and have it use, say, a webcam as a capture device?

D Finnigan

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Sep 10, 2015, 4:27:08 PM9/10/15

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Apparently so much that no one wants to talk about it. :-/

Michael J. Mahon

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Sep 10, 2015, 5:17:25 PM9/10/15

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I'm surprised.

The IIgs video modes are already emulated, so video capture, genlock,
chroma-key detection, and "mixing" are the only remaining functions. ;-)
--
-michael - NadaNet 3.1 and AppleCrate II: http://home.comcast.net/~mjmahon

Steve Nickolas

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Sep 10, 2015, 8:14:58 PM9/10/15

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On Thu, 10 Sep 2015, Michael J. Mahon wrote:

> D Finnigan <dog...@macgui.com> wrote:
>> Brandon Taylor wrote:
>>> How much work would it be to implement emulation into GSport of an Apple
>>> IIgs Video Overlay Card, and have it use, say, a webcam as a capture
>>> device?
>>>
>>
>> Apparently so much that no one wants to talk about it. :-/
>
> I'm surprised.
>
> The IIgs video modes are already emulated, so video capture, genlock,
> chroma-key detection, and "mixing" are the only remaining functions. ;-)
>

It would be interesting to be able to, say, play a video file through
mplayer or ffmpeg underneath the IIgs display and then output the
resulting pseudo-genlocked video through ffmpeg... YOWIE!

Kinda like the old days of VHS fansubbing...

-uso.

Bill Buckels

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Sep 11, 2015, 7:55:20 PM9/11/15

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OK I'll break my silence... but I can't tell you how much work it would be.
David Schmidt would be a better guy to comment on that.

I do have a question for you though...

What kind of rendering would you expect for these alleged captures? Some old
crappy rendering like was on the Apple IIgs with the utilities that existed
back then, or some decent rendering like my A2B converter provides?

Your main problem is not emulation, it is the garbage that you would get if
you used old crappy rendering with your frame-grabs. Go look at some of my
recent comparisons of Prism, etc. to see the old junk. I posted them here
already.

Revisiting conversions for The VOC 320 x 400 Interlace Mode is on my list
now that I have some decent stuff working for SHR 320 x 200. Bmp2SHR
provided 320 x 400 conversions but not to the quality that I can do now.

Also be aware that VOC12-bit captures are inadequate for comparable quality
to today's video... even the 16-bit Targa Boards I was working with back
then did not provide the quality that we enjoy today with modern color
science like A2B uses...

Perhaps I misunderstand your wish and maybe I am on another of my tangents,
but I would think that you'd want to build a better VOC... like a SteamPunk
VOC that didn't really exist, that captures and renders 24-bit like A2B.

Judging from the lack of interest in a better SHR converter like A2B I
wonder how much interest there would be in what I am talking about anyhow.
And if Schmidt or someone else did add VOC capture to GSPort maybe only 5 or
10 people would be interested. I also hope I am not being too pessimistic.
But the old rendering that I have reviewed was just soooooooooooooooooooo
bad.

Bill