[comp.sys.amiga.graphics] tv on workbench

Duncan.Lewis@bbs.acs.unc.edu (Duncan Lewis) (06/05/91)

After the lengthy discussion of graphics under intuition  and colors etc.
WHy couldn't one do this..
make a videoboard that locked onto a chromakeyed region.
and then overlay its video into that region.
in more clear terms... let intuition open a window on workbench
in "blue screen"(with the appropiate borders etc)
let the monitor signal enter this board, let the board scale down
ntsc video and overlay it at teh given coordiantes and sizing.
then out to monitor.  Just pass the region information to
the board and shut it down if theres a window move or resize until
that is executed.  Obviously audio is not a problem.

possible no?
ok I'm not a tech-head enough to do this but the same principle
could be applied to a vga graphics board output to the same board.

comments welcome on this newsgroup.  I am sure theres a flaw
or it would have been done already.

 -Dunc.

--
   The opinions expressed are not necessarily those of the University of
     North Carolina at Chapel Hill, the Campus Office for Information
        Technology, or the Experimental Bulletin Board Service.
           internet:  bbs.oit.unc.edu or 128.109.157.30

doctorj@en.ecn.purdue.edu (Jeffrey W Davis) (06/05/91)

In article <4004@beguine.UUCP> Duncan.Lewis@bbs.acs.unc.edu (Duncan Lewis)
writes:
>
>After the lengthy discussion of graphics under intuition and colors etc.
>Why couldn't one do this..
>make a videoboard that locked onto a chromakeyed region.
>and then overlay its video into that region.
>in more clear terms... let intuition open a window on workbench
>in "blue screen"(with the appropiate borders etc)
>let the monitor signal enter this board, let the board scale down
>ntsc video and overlay it at the given coordiantes and sizing.
>

Chroma-key is not necessary in this case and would be a technical overkill.
It is already possible to genlock computer video over source video.  All
that would have to happen is the WB background color be changed to
something other than color 0 and use color 0 for the transparent part of
your TV window.  Resizing and placement of the TV input signal would be an
interesting project; but definitely not impossible.  It is entirely
possible to allow movement and resizing of the TV workbench window in
real-time WITH video continuously running inside.

>possible no?
>ok I'm not a tech-head enough to do this but the same principle
>could be applied to a vga graphics board output to the same board.

Any video with genlock capabilities could use such a device.  Essentially
the device would simply be a video effects module with only one effect;
resizing and positioning video.  Give it a common interface (serial?) for
recieving its co-ordinates for the video signal and you have something
marketable for use on virtually any computer system.

I would certainly enjoy having one of the things.  I have thought of making
such a device, but that's as far as I got.  You could call it WBTV
(Workbench Television) and make a few $million$ in the process.

>
>comments welcome on this newsgroup.  I am sure theres a flaw
>or it would have been done already.

It has been done already.  You see it all of the time on TV's;
picture-in-a-picture.  Maybe nobody has really thought about doing this on
the Amy who was in a position to do something about it?  I would certainly
like to see that change!

> -Dunc.

***********************************************************
* Jeff Davis                * Relax! And get into    ///  *
* doctorj@en.ecn.purdue.edu * the STRESS!!!         ///   *
*                           *                   \\\///030 *
*                           * -Gigahertz!-  Amiga\XX/ 882 *
***********************************************************
	    -=[ In Stereo Where Available ]=-

amigan@cup.portal.com (R Michael Medwid) (06/06/91)

I have seen such a device on MACs..a TV board..but because of Amiga's video
compatibility I would think designing such a creature for the Amy would be
much easier..stilll not sure how they do that with the Mac..

..my 2c