VGA2EGA (c) Copr. 1988-89 Lawrence Gozum & Marvin Gozum
Version 3.0 User Manual
This product is distributed AS IS. The authors specifically disclaim
all warranties ,expressed or implied, including ,but not limited to,
implied warranties of merchantability and fitness for a particular
purpose with respect to defects in the diskette and documentation, and
program license granted herein, in particular, and without limiting
operation of the program license with respect to any particular
application use or purpose. In no event shall the authors be liable
for any loss of profit or any other commercial damage including but
not limited to special, incidental, consequential or other damages.
You may use this program on a TRIAL BASIS only; this means that you
may freely evaluate the usefulness of this program for 10 DAY TRIAL
PERIOD. Should you find this program useful, you must register it
(see last section of this manual). You will then be provided with
the latest releases of applications that will run on your system.
You may freely distribute copies of this program in its UNMODIFIED
state provided you do not include it in other software packages, with
the exception of distributing it as part of a bundle of Public Domain
or shareware programs on a single diskette. You may not charge more
that $3.50 for copying and/or distributing this program in the absence
of recognized Users Group guidelines (e.g., Association of Shareware
Professionals or New York Amateur Computer Club)
WHAT IS VGA2EGA ?
VGA2EGA is a utility that converts colored GIF pictures and any of the
following listed below to error-distributed, dithered, 16-Color EGA
pictures. You can optionally save 4 planes for each red, green, blue,
and white(grey) plane to .PCX (ZSoft) files as a Desktop Color
Seperator (DCS), where Cyan=Grn+Blu, Magenta=Red+Blu, Yellow=Red+Grn.
You can view pictures in low-res EGA 320x200x16 mode (32KB EGA cards)
or as high as 800x600x16 in EEGA modes.
1) ANY colored GIF picture (32 colors and up recommended), with any
size (up to 2048 x 2048 x 256).
2) ANY VIEWABLE VGA/MCGA 320x200x256 picture captured with VGACAP;
3) VGACAD pictures;
4) 16-color pictures converted to 320x200x256 with EGA2VGA.
VGA2EGA requires, at the minimum, a 32KB EGA card (320x200x16 mode).
For viewing, VGA2EGA supports video modes in EGA 320x200x16, EGA
640x200x16, EGA 640x350x16, EEGA/VGA 640x480x16, and hi-res EEGA/SVGA
modes up to 800x600x16.
VGA2EGA converts your colored pictures to 4-plane colored dithers
using a unique error-distribution algorithm; it uses a Floyd-Steinberg
matrix with Stucki filter values (8,4,2,2). Users can individually
adjust the CMY and/or RGBI color levels and RGBI contrast levels,
dither density, and image size to suit their tastes.
WHAT IS VGACAP ?
VGACAP is a terminate-stay-resident (TSR) utility that allows you to
capture the 256 color palette and screen in the 320x200x256 color mode
and save both the palette and screen in "Bloadable" formats. VGACAP's
main purpose is to capture and "Bsave" the pictures of commercial and
Shareware viewing/painting/graphics/CAD programs.
VGACAD (one of the first 256 color paint/CAD shareware programs
distributed in the Public domain) will load the captured pictures for
extensive image processing and editing.
EGA 32KB (minimum). We are stating that about 512KB of memory is
required, although it uses about 2/3 of that.
You MUST have a VGA or MCGA adaptor (at least BIOS compatible) present
and an analog monitor to use VGACAP. VGACAP uses less than 2K of your
available memory !
HOW TO USE VGACAP
Run VGACAP before entering your painting/CAD or digitized picture
drawing/paint/CAD program. Your current screen and palette will be
saved in your default drive and directory in the standard Bsave format
for all BASIC programs.
The first time you run the program it will save your screen and
palette to SCREEN00.BLD and SCREEN00.PLT respectively. If there is an
existing SCREENxx.BLD or SCREENxx.PLT file, then it will increment to
the next higher number. You can use your favorite memory managers to
remove this TSR or reboot to release it from memory.
Note: When in DOS or using a picture viewer (e.g., PICEM, VPIC,
VGAGIF) or application which requires a keypress to continue, it
is necessary to hit another key after hitting the 'HOTKEY'.
LOADING PICTURES INTO VGA2EGA
Two formats are accepted by VGA2EGA: GIF and BLD/PLT files; At the
start of the program, you will be prompted to select [G]IF or [B]LD
files to to selected or [Q]uit to exit.
When loading GIF pictures, if you have a VGA/MCGA card, VGA2EGA will
display the picture as it decodes it and show its conversion to a 256
grey scale picture. All other cards will load in memory; GIFPUB
automatically senses if you have a VGA/MCGA or SuperVGA card.
All pictures are interpolated to a 320x200 size. As such, LARGE
SuperVGA GIF files (e.g., 640x480x256, 800x600x256 and 1024x768x256)
are interpolated to 320x200x256; succeeding updates will take
advantage of the rich color information in LARGE GIFs by creating
virtual disk buffers. SQZGIF is recommended for LARGE GIF pictures to
retain more color information for better color rendition.
16-color EGA/EEGA/VGA pictures will also be interpolated; it is highly
recommended that you use EGA2VGA to process such pictures before
loading into VGA2EGA.
You can select any filename by moving a highlighted bar (with the
arrow keys) and pressing the
to select a different PATH, while
file, be sure it has a corresponding *.PLT file or a error message
PATHs MUST end with a backslash character "\" or your specified PATH
will be rejected (an error beep will result). The following are legal
Every captured picture, VGACAD picture, converted EGA2VGA or SSQZGIF
or MAC2GIF picture will have two files: the screen and palette. The
extension .BLD stands for BLoaD and .PLT for PaLetTe.
THE MAIN MENU
After successful loading of your picture you will see these options:
(1) 32 KB RAM STD EGA 320x200x16
(2) 64 KB RAM STD EGA 640x200x16
(3) 128 KB RAM STD EGA 640x350x16
(4) 256 KB RAM STD EGA 640x480x16
(L)aboratory STD EGA 640x350x16
Select the letter or the number to initiate that function or option.
Whenever you select a video mode to be created you will see these
options (this screen shows blanks filled with examples).
Video Mode/Aspect Ratio: EGA 640x350
Image Width (pixels) : 640
Image Height (pixels) : 350
Resizing Factor (1-100): 100%
Pathname : C:\GIF\
Filename : NONAME.GIF
Image Width and Height are set by the video mode you have chosen and
cannot be changed except when e[X]tended EGA User Mode is selected.
In this example, the Image Width and Height matches the full screen
since Resizing Factor is 100%; if it were 50% then each number will be
cut in half. To maintain your aspect ratios in EEGA modes, always
start with a Resizing Factor of 100% then reduce it later.
When a standard EGA video mode or preset EEGA mode is selected, the
Image Height and Width will always follow what is stated in the Video
Mode/Aspect ratio line; only the Resizing Factor can be altered. To
retain an old setting, press return and the setting will remain.
VIEWING & SAVING
While viewing the picture in EGA 640x350x16 mode or any supported EEGA
mode (up to 800x600x16), you can change the palette to alter the tone
of the picture. Users with 32KB and 64 KB EGA cards cannot change the
palette since it is limited to 16 colors and optimized for 8 colors.
All other users have 9 EGA palettes to choose from. Simply press the
number from 1 to 9 to see the effect of a different palette on your
If you are happy with the results, you can press return and the image
will be saved with the proper screen and image data in a GIF file.
If you intend to use VGA2EGA as a Desktop Color Separator, press [P]
to save 4 .PCX files; each file will correspond to the Red, Green,
Blue and White(Grey) plane of the picture and are labelled
Since different color printers (particularly thermal) have different
CMY mixtures, saving to RGBI files allows the user the flexibility to
determine if one component of CMY is higher than the other. CMY or
Cyan-Magenta-Yellow can be interpreted as (Cyan-Blue, Magenta-Red, and
Yellow-Orange) or (Cyan-Green, Magenta-Blue or Yellow-Green) or any
combination thereof; as such, you decide which combination of RGBI is
appropriate for your CMY separation; there are 8 possible combinations
for CMY. Remember, CMY is made by combining Grn+Blue, Red+Blu, and
Red+Grn primary colors respectively.
To get the BEST color dithering, we suggest that you experiment with a
small image (e.g., EGA at 50%) while interactively adjusting the color
levels, contrast levels and dither density levels. When satisfied
with the results, you can progress to larger sizes up to EEGA
When you select (F)ine Tuning, you can adjust the global amounts of
Red, Green, Blue and White(grey) in you picture. At default it is
100%; this can be increased up to 200%. 16KB and 32KB EGA users need
not adjust the White(grey) level since only 3 planes or 8 colors are
While "fine tuning", you can adjust the contrast levels for each of
the RGBI planes. Increasing the contrast will increase the amount of
"black" in the picture by making a sharp cutoff (i.e., no color will
Dither Density is how closely packed neighboring pixel will be; at
default this is set to 1 - the highest density possible. If you want
to "spread the dots" in a less packed manner, you can increase this
level up to 200.
Selecting (L)aboratory will put you in EGA 640x350x16 mode and will
show your picture with 70% of the size; you can reduce the size but
cannot exceed 70%. While in the Lab, you can alter the red, green,
blue, grey, cyan, magenta and yellow color levels and RGBI contrast
levels as you would with the "fine tuning" option. However, here you
can interactively see the change.
To select a plane for modification press A,R,G,B,C,M,Y,W; each letter
refers to ALL, red, gren, blue, cyan, magenta, yellow, and white
Once a plane has been selected, pressing the "plus"(+) key or the
"minus"(-) key will increase or decrease, the color level or the color
contrast of selected plane(s). The
contrast and color level modification modes.
A MODE indicator will tell you what your current plane selection is
and what modification mode is active. "A Color" will mean that ALL
color levels of all 4 planes will be affected. "R Contrast" will mean
that only the RED color level will be affected. An [U]ndo function is
provided to reset all color and contrast values; so, feel free to
experiment ! Below the displayed image are bargraphs showing the
corresponding RGBWCMY color levels and RGBI contrast levels.
While in the (L)aboratory you can select from 9 EGA palettes and save
the finished image. If you picture looks good in the Lab; it will
look infinitely better when expanded to large sizes or in EEGA modes.
PRESET AND USER EXTENDED EGA (EEGA) MODES
Press the [H]elp screen option when using Present or E(x)tended EGA
User Modes for more information of various EEGA cards supported. We
have built-in 8 Preset EEGA modes.
You can set any Extended EGA mode that your video card supports up to
800x600x16 IF YOUR EEGA CARD SUPPORTS THE STANDARD BIOS CALLING
CONVENTION FOR SETTING VIDEO MODES. The Video7 Vega and Everex EVA480
cards are among the few that require their own method for setting the
EEGA mode; use the (E)verex and (V)ideo7 preset modes instead.
In general, all Chips & Technologies (C&T) chip based cards use the
standard BIOS convention for calling EEGA modes.
SVGA modes (e.g., 1024x768x16) do not follow the EGA memory mapping
since the number of bytes exceed 256KB and require memory banking;
thus, 800x600x16 IS THE LIMIT (until we upgrade VGA2EGA to support
SVGA 16 color modes for specific SVGA cards).
WARNING: PRESET AND USER EXTENDED EGA MODES ARE NOT DETECTED NOR
ERROR-CHECKED ! IF YOUR CARD DOES NOT SUPPORT IT, DON'T USE
IT; UNPREDICTABLE RESULTS WILL OCCUR. CHECK YOUR VIDEO
CARD'S USER MANUAL FOR VIDEO MODE AVAILABILITY, MODE NUMBERS
AND SCREEN DIMENSIONS TO BE USED.
BONUS: Registered users of VGACAD v1.4-1.5, VGA2EGA v1.0, SQZGIF
v1.0-v1.3, GIFDOT v1.0-1.3, MAC2GIF v1-2 and/or EGA2VGA
v1-3 and/or GIFPUB v1.0-v1.4 are considered registered.
Copy your REGISTER.OVL file into the directory of VGA2EGA
and it will operate as a registered version. IF YOU HAVE
NOT REGISTERED ANY OF THESE PROGRAMS, DO SO NOW; when
VGACAD v1.60 is released, all new releases will require
REGISTER.V16 to operate as a non-shareware version.
For 19.95 (outside of U.S.A. add USD $15.00) you will be entitled to
the latest update of VGA2EGA and REGISTER.V16 file (when released).
The following programs listed below are provided (latest copy or
update) to registered users. As much as possible, we are
reprogramming all utilities to work with ANY video card; programs
that, at present, work with ANY video card are: GIFPUB, GIFDOT,
EGA2VGA (v2-3), MAC2GIF and SQZGIF. We intend to modify all utilities
to have device-independent graphics capabilities (with the obvious
exception of VGACAD, VGACAP, VGA2EGA, and CGA2VGA). If you upgrade to
VGA, please inform us as soon as possible so that we may send you
VGA-dependent releases too.
* Device-independent utilities
GIFPUB - converts 256 color GIFs to B&W images of varying sizes
for desktop publishing/printing as .PCX (ZSoft format for Ventura
Desk Top Publisher, First Publisher, Publisher's Paintbrush, PC
Paintbrush+) or rename files to .PCC for importing in Aldus
GIFDOT - converts 256 color GIFs to B&W images of varying sizes
for printing on IBM and Epson compatible printers (separate
drivers). Several print sizes with perfect aspect ratios.
Variable Brightness and Contrast Stretching. Single or Double
pass printing. Histogram Analysis
SQZGIF - converts LARGE GIF pictures (up to 2048x2048x256) to
320x200x256 using interpolation and "color averaging" techniques
to blend/smooth "jaggies" inherent in reducing LARGE GIFS while
retaining a maximum of color information. Version 1.3 is now
300% FASTER and features the same user interface.
MAC2GIF - converts .MAC ("readmac") pictures to 5-16 grey shades
or color and saves results as .GIF or BLD/PLT file, and other
formats; graphics are viewable in VGA, MCGA or EGA - no video
card is required for direct Black & White conversion to GIF.
EGA2VGA (v2.0) - converts GIFs (16 colors and below) or ANY
VIEWABLE 2-16 color EGA/EEGA/VGA picture to 320x200x256; creates
256 new colors; outputs load directly to GIFPUB, GIFDOT, and
VGACAD. If you load converted MAC2GIF pics you can smooth and
convert Black & White images to grey shades; B&W GIFs and
captured pics will also be "smoothed" into grey shades.
* Device-dependent utilities/applications
VGACAD - extensive paint/image processing program for VGA/MCGA
users; v1.50 features extensive paintingcapabilities, an
integrated GIF interface, Airbrushes, color and grey image
processing functions (smoothing, noise removal, shading, contrast
stertching, edge detection, high frequency-boosting, ... more),
Bezier/spline curves, multi-featured Cut&Paste, variable sizing,
multi-directiona 256-color gradient fills, 256 color 16x16
pattern fills, and a LOT of other 256-color capabilities.
Whats next ?
SYNPCX is utility to convert dithered, monochrome .PCX (Zsoft) files
to smooth grey shades. This utility is primarily designed to convert
scanned (e.g., Logitech & DFI hand scanners) Black & White images,
saved to a .PCX file, for use and image processing with VGACAD,
redithering/resizing with GIFPUB, printing with GIFDOT, or EGA
conversion with VGA2EGA. SYNPCX will be graphics device independent
(No Video Required).
On the longer term, you can expect radical changes in VGACAD and
VGA2EGA. VGA2EGA updates will include color optimization and
maximization to take full advantage of its 16 out of 64 color with
color dithering. We are also, developing VGASHW (a 256-color
presentation system), VGACBT (the PROGRAMMABLE Computer-Based Training
counterpart of VGASHW) AND MANNEQUIN (what "Weird Science" tried to do
in the movie it will do on the computer screen with potential
applications for Advertising and Fashion Design, aside from creating
your own artistic nudes).
If you support maverick authors like us, we will continue to develop
innovative products like nothing seen commercially - otherwise they
will, as many (sigh!) good Shareware programs, simply "DIE" from lack
of support ! Compare the cost/benefit ratio of any of our products
with commercial products; we want to continue supporting and
developing these products. Please support the User-Supported
(Shareware) concept; you, and you alone, determine whether it will be
worthwhile to continue developing.
To register, send in the registration form and check payable to
Dr. Marvin Gozum
2 Independence Place Apt. 303-2
6th & Locust Street
Philadelphia, PA 19106
NEW! 3.5" disk users: We are now supporting this format.
If you want your updates in this format, add $10.00.
Graphics Interchange Format and GIF are trademarks (tm)
of CompuServe Inc. an H&R Block Company.