Path: utzoo!dciem!king
From: king@dciem.UUCP (Stephen King)
Newsgroups: comp.sys.amiga
Subject: Re: Need some help
Message-ID: <2653@dciem.UUCP>
Date: 17 Feb 88 14:18:40 GMT
Article-I.D.: dciem.2653
Posted: Wed Feb 17 09:18:40 1988
References: <8176@sunybcs.UUCP> <2343@gryphon.CTS.COM> <1498@uhccux.UUCP> <652@gethen.UUCP>
Reply-To: king@dciem.UUCP (Stephen King)
Organization: D.C.I.E.M., Toronto, Canada
Lines: 33
Summary: 

In article <652@gethen.UUCP> farren@gethen.UUCP (Michael J. Farren) writes:
>My understanding is that the Toshiba does NOT do true de-interlacing, in
>the sense of taking two screens of video and putting them to the tube as
>one, non-interlaced screen.  Instead, it does interpolation of the two
>scan lines to fill in the space between the lines.  This is a
>significantly easier task, and no help at all with the interlace problem
>of the Amiga.

Interpolation between lines is an EASIER task? I would have to disagree.
It seems to me that, in order to do this interpolation, the video must
be de-interlaced first, due to the time-sequential nature of the video
fields. Remember that with an interlaced image adjacent lines are separated
in time by ~1/60 sec. To provide the interpolation, a system must store at
least a whole field, then interpolate and display while the next field arrives.
This is a more complex scheme than simple de-interlacing as the number of scan
lines will double to ~960 (displayed).  I could design a de-interlacer quite
easily, based on work I have already done, but this interpolation scheme
presents some unique problems, not the least of which is a simple memory
circuit which can keep up at the required dot rate.

On the other hand, you may be suggesting that adjacent lines from the SAME
field are used to interpolate the in-between values. This is simpler, but
suffers from some limitations, namely that entities one line high will still
flicker, as the information will only be present every other field. Of
course, you could still turn down the brightness, contrast and room lighting
to make this flicker less noticeable...		:-)

					Stephen (non-fiction) King
-- 
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