Path: utzoo!utgpu!water!watmath!clyde!att-cb!att-ih!pacbell!hoptoad!unisoft!gethen!farren
From: farren@gethen.UUCP (Michael J. Farren)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Fixing flicker, & future frame rate issues
Message-ID: <869@gethen.UUCP>
Date: 17 Apr 88 07:07:35 GMT
References: <11157@ut-sally.UUCP> <8528@agate.BERKELEY.EDU> <11182@ut-sally.UUCP> <11255@ut-sally.UUCP> <2972@leo.UUCP>
Reply-To: farren@gethen.UUCP (Michael J. Farren)
Organization: There's Unix there in Oakland
Lines: 24

In article <2972@leo.UUCP> harald@leo.UUCP ( Harald Milne) writes:
>> 	Flicker:  A perceived INTERMITTENCE in an ENTIRE image, as in successive
>> 	frames interleaved with intervals of 'darkness' (= absence of image).
>
>	For us normal Amiga types, this is called "Non interlaced"
>Where alternate "half frames" are absent. That gives us the lines without
>information in non interlaced modes.

This is not what happens at all.  Non-interlaced mode does NOT have
"lines without information", and alternate half-frames are NOT absent.
The difference is simply that in non-interlace, the lines are displayed
in the same position on the screen each 60th of a second.  What you get
are 60 screens per second, each 200 lines tall.  In interlace mode, every
other half-frame is displayed on the screen such that it falls between
the lines of the preceding half-frame.  Thus, you get a total of only
30 screens per second, each 400 lines tall.  There are no "lines without
information" in either mode.


-- 
Michael J. Farren             | "INVESTIGATE your point of view, don't just 
{ucbvax, uunet, hoptoad}!     | dogmatize it!  Reflect on it and re-evaluate
        unisoft!gethen!farren | it.  You may want to change your mind someday."
gethen!farren@lll-winken.llnl.gov ----- Tom Reingold, from alt.flame