Path: utzoo!attcan!uunet!cbmvax!hood From: hood@cbmvax.commodore.com (Scott Hood) Newsgroups: comp.sys.amiga Subject: Re: Commodore De-interlacer Message-ID: <15790@cbmvax.commodore.com> Date: 11 Nov 90 04:00:39 GMT References: <3766.658255715@lemsys.UUCP> Reply-To: hood@cbmvax.commodore.com (Scott Hood) Organization: Commodore, West Chester, PA Lines: 71 In article <3766.658255715@lemsys.UUCP> clemon@lemsys.UUCP (Craig Lemon) writes: >In a message posted on 7 Nov 90 22:03:45 GMT, >hood@cbmvax.commodore.com (Scott Hood) wrote: >SH>In article <1990Nov7.181228.3182@uokmax.ecn.uoknor.edu> drtiller@uokmax.ecn.uoknor.edu (Donald Richard Tillery Jr) writes: >SH>>>> (about the flickering first half line) >SH>>>> Every time this subject comes up, I ask why the C-A deinterlacer can't >SH>>>>handle the first scan line in whatever way the flickerFixer does. I've never >SH>>>>seen any answer to this. I'd just like to know whether the problem is due to >SH>>>>a design or manufacturing error, or is the deliberate result of some cost >SH>>>>reduction measure. > >SH>>>So the question arises: What does flickerFixer put in there? > >SH>>Yes, but what does the electron beam scan have to do with the problem? >SH>>Whatever happens to the signal at the monitor isn't causing the 1/3 >SH>>line flicker, the de-interlacer is. That means that the timing in >SH>>the A2320 doesn't sync every frame until about 1/3 of the way into the >SH>>first scan line. The lack of sync causes a variation from frame to >SH>>frame that results in oposing information appearing as flicker. >SH>>Obviously the FF overcomes this by syncing earlier or (more likely >SH>>since I talked to the FF guy and this seems to be his technique for >SH>>eliminating problems - i.e. garbage on the right edge) just covering >SH>>the offending video with blanking. A similar solution for the A2320 >SH>>would be reasonable (BTW, the FF displays "about 719 by 479 hi-res >SH>>pixels", I wonder why :-). >SH>> >SH>>Rick Tillery >SH>>(drtiller@uokmax.ecn.uoknor.edu) > >SH>I guess that I should put this one to rest once and for all. The >SH>problem is with the way that the Amber chip did the de-interlacing. It >SH>has nothing to do with beam position or sync or any other such >SH>infromation, but these are not unreasonable guesses! When the Amber >SH>chip was in development I did not think that this was such a bad >SH>artifact (I know, I know, how could one be so foolish!) and only a few >SH>people said anything about this flickering 1/2 line. >SH> >SH>Scott Hood > > This is necessarily a reply directly to Scott. When I first heard >of the release of the A2230, I thought, "Great!, and look at the price!" >Now I'm wondering if it is so great. Is the general conensus that the FF >is much better than the A2230? Is this flickering problem ONLY on the >first scan line or does the whole screen flicker a bit? Are there any >other known problems with the A2230? What about colour etc...How does the >actual picture quality compare with the FF (should be exactly the same, I >know. I'm just making sure.)? > >-- > Craig Lemon - Kitchener, Ontario. Amiga B2000/10--2400 bps--AmigaUUCP 1.03D > clemon@lemsys.UUCP or lemsys!clemon@xenitec.on.ca > ....!{uunet}!watmath!xenitec!lemsys!clemon The flickering 1/3 line in on the top left-hand extreme corner and does not effect the rest of the display!! It is present in both NTSC and PAL interlace modes but not the non-interlace screen modes. The A2320 supports all 4096 colors of the Amiga, as many colors as the Amiga is capable of generating, which of course also works with the `Dymanic HiRes' modes of the Newtek (TM) Digaview device. As for picture quality there should be no differance, only more functionality for less money. I hope this helps! The A2320 also is available on the developer price list (not sure for how much though). Scott Hood (Check it out for yourself!) -- -- Scott Hood, Hardware Design Engineer (A3000 Crew), Commodore-Amiga, Inc. {uunet|pyramid|rutgers}!cbmvax!hood hood@cbmvax.cbm.commodore.com "The views expressed here are not necessarily those of my employer!"