AST - Vision Plus Enhanced video digitizer card

[crownmi@zot.io.org (Myles Fudge)]

Date: Sun, 8 Sep 1996 23:05:22 -0400 (EDT)
From: Myles Fudge <crownmi@io.org>
To: Matt Portune <mportune@telerama.lm.com>
Cc: Myles Fudge <crownmi@io.org>
Subject: Re: Better Broadcast Graphics than VCR Companion?
 
Hi Matt.  I do hope that what I posted was correct.  After some recent
scrutinizing, I wonder.  I'll post my reply to you to csa2 for all to 
read.
 
On Sun, 8 Sep 1996, you wrote:
 
> In article <50u1hf$g8d@zap.io.org> you wrote:
> > camcorder, VCR, and cable TV with the card.  The accompanying 
software
> > was written to capture 15 fps in real time, to avoid jitters in 
capture.
>
> Hi Myles,
>       You caught my attention here.  What version of the software are
> you using?
 
Allison 1.0.5 Update, as stated on the 3.5 disk and the 'about' in the
software, Allison.SYS16.  The disk label is (c) 1991-1993, and the
software is only (c) 1990, 1991.
 
> I have the latest card (v2.0)
 
My card has several components added after the manufacturing was completed.
The EPROM on the far right of the card has a sticker labelled "Allison
2.0 ROM (c)93 AEC".  The card is silkscreened AST - VisionPlus on the
front, and has two stickers on the back: "ASSY.REV.X6" and the serial
number (3200 series).  The card is an AST Vision Plus Enhanced model,
not a VisionaryGS model.
 
> but the software doesn't have any options to slow down to 15fps for
> jitter reduction.  And believe me, there's a whole lot of jitter goin' on.
 
My software doesn't have that option, either.  That information was in
the documentation, as I recall.  Referring to the original software
(which is not included on the 1.0.5 disk) VisionEffects, the manual
states an Appendix C, Firmware Protocol, on page C-7 that:
 
"A video signal consists of two half-frames.  The first half-frame
contains all even numbered lines, the second half-frame contains all odd
numbered lines for a total of 525 lines.
 
One half-frame is received every 1/60th of a second.  The
AST-VisionPlus card does not look at the half-frame information.  The
first pass digitizes pixels of the first half-frame, the second pass
digitizes pixels of the second half-frame.  This reduces moving
distortion, but makes horizontal lines look jagged.  The protocol allows
the firmware to skip every other frame so that only all even or odd
numbered lines are digitized.  This produces clean horizontal lines at
the cost of higher moving distortion."
 
>From the file ReleaseNote.TXT, on the 1.0.5 disk:
 
"PLEASE NOTE: The Original AST VisionPlus manual has been included in this
package for references to installation only.  The software mentioned in the
manual, AST VisionEffects is no longer supported by the VisionPlus hardware.
This is a preliminary release, allthough it is a fully functional version.
This version is idendical to version 1.0.4 except that it will function with
the AEC/AllyROM on your card, and monochrome fullscreen digitizing has been
enhanced to use the new ROM."
 
The 'Hints for better pictures' section of the file Prelim.Man.TXT does
not provide any technical digitizing information so I do not know for
sure if the 15 fps feature is utilized by the newer Allison.SYS16 program.
I do recall from watching fullscreen greyscale realtime video capture/playback
that it looks smooth enough to be 30 fps.
Anyhow, it was not a selectable software option, it was hard coded into
the original software.  I recall reading somewhere advising that the code
does 15fps and that it could be changed to 30fps.
 
The Developer's Guide (Appendix C) indicates that bit 3 of Byte 1 in the
descriptor block is set to 1 to skip every other frame to get clean
horizontal lines.
 
Other notable information is indicated on page 1-4, the card
*  provides direct IIgs memory access so images can be displayed
   "live" on the screen
*  displays images in either 320x200, or 640x200 (B&W only)
*  lets you zoom in or zoom out on graphic images
*  lets you control aspect ratio to create stretching effects
*  PaintworksPlus is included in the package for further editing
 
There is enough developer information in Appendix C to choke a horse...
there's no reason why there isn't hordes of AST shareware/freeware (like
a pulldown video NDA, GS to GS modem video conferencing, auto
uploading of local realtime images to a website for immediate worldwide
viewing, etc... [yeah, I've given it some thought ;) ] ) except that
few people seem to own one of these cards, even though you can call
Alltech and order one right now.
 
The only other suggestion I have about image quality is in calibration:
"If you've purchased Allison as an upgrade and aren't happy with the
quality of color and monochrome images you're getting, the most likely
cause is board calibration.  Excellent Software is offering
recalibration to existing users of VisionaryGS boards at $16.00
(includes shipping) per board.  Recalibration matches your board to
Allison and allows you to get the best possible image."
 
> I still wish they would release Allison 2.0, as originally promised.
 
Absolutely.  In their own words:
 
"This is a preliminary release, allthough it is a fully functional
version. This version is idendical to version 1.0.4 except that it will
function with the AEC/AllyROM on your card, and monochrome fullscreen
digitizing has been enhanced to use the new ROM.  Upon it's release, you
will also receive Allison 2.0 and a user manual for it, it is included
in the purchase price of this product."
 
Yeah, "it is included in the purchase price of this product".  Hmmm...
where's my lawyer...
 
Is this support information still current?
 
"Alltech Electronics
619/721-7733
Fax 619/721-2823
 
Alltech Electronics,
602 Garrison St.
Oceanside, CA 92054
 
Online support is available on America Online in the Apple II
Art & Graphics forum.  Contact AFL Scott or Duelplay."
 
This is obviously an area where the programmers and developers can step
in and fill the gap.
-- 
Myles Fudge  (crownmi@io.org)
http://www.io.org/~crownmi/pleasure.html