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<& % $ 66 6 6 1 80 1 14 22 30 38 46 54 62 70 70 70 70 70 70 70 70 70 70 70 70 70% >
GIF2JPG and JPG2GIF
Version 1.41
Handmade Software, Inc.
15951 Los Gatos Blvd., Suite 7
Los Gatos, CA 95032
+1 408 356 4143 fax
+1 408 358 1292 tel
uucp: apple!netcom!hsi
internet: hsi@netcom.com
compuserve: 71330,3136
Copyright (c) 1990-1991
All Rights Reserved
Introduction
JPG2GIF and GIF2JPG are a set of shareware programs which
convert GIF images to JPEG images and JPEG images back to GIF
images.
Why would you want to do this?
Because typically JPEG files are several times smaller than
GIF files. So, by converting images from GIF to JPEG you save
on modeming time, long distance charges, and disk storage
requirements. The disadvantage is that you can't view JPEG
files directly; you have to convert them back to GIF files so
that you can use your favorite GIF viewer.
Using GIF2JPG & JPG2GIF
To convert .GIF files to .JPG files:
GIF2JPG [options] [files...]
If any .JPG files with the same name already exist you will be
asked whether to overwrite them. If any GIF89A files are
encountered you will be asked whether or not to convert them.
GIF89A files are not automatically converted since they can
contain text and multiple images; this information will be
lost when the image is converted to a JPEG file.
To convert .JPG files to .GIF files:
JPG2GIF [options] [files...]
If any .GIF files already exist you will be asked whether or
not to overwrite them.
There are two options which are common to both programs:
-a: automatically proceeds (overwriting any existing
files and converting GIF89A files).
-k: kill (removes) the original files after they are
processed.
The GIF2JPG program has an additional option:
-q[n]: specify the JPEG quality factor which will be
used when compressing GIF files.
The default is 55.
A lower number will result in a higher
compression ratio, but a lower quality image.
Specifying a very low quality factor (less than
15) will result in poor quality images.
Note that you may specify wild cards as part of the file name
and that multiple file names may be specified.
Examples:
GIF2JPG -q30 *.gif
Will convert all .gif files in the current directory to .jpg
files, using a quality factor of 30.
JPG2GIF -k -a test.jpg madonna.jpg n?.jpg
Will convert the specified files back to .gif files, deleting
the .jpg files and automatically overwriting the existing GIF
files.
Hardware Requirements
An IBM PC or clone (at least an 80286 for any kind of
performance).
A hard drive (JPG2GIF needs to open temporary files while
processing; you must have at least 3 times as much disk space
available as the largest image you are converting (for
example, a 640 by 480 file requires 1 Megabyte of free space].
MS-DOS or PC-DOS 3.1 or later.
380K of available RAM.
Shareware
GIF2JPG and JPG2GIF are shareware programs. Please feel free
to distribute them by giving copies to your friends, uploading
them to bulletin boards, and trading them at user clubs. You
must distribute them unaltered, and as a set, including this
document. You may not sell these files for more than a
reasonable media duplication cost ($7.00).
You may use GIF2JPG and JPG2GIF on a trial basis for two
weeks; after that you must register by sending us $20 or stop
using them. The last page of this document is an order form
which you may use. When you register, you will be shipped a
copy of the latest version of JPG2GIF and GIF2JPG (if,
according to your order form, you already have the latest
version, we will ship you the first update when it is
available).
By registering you will encourage us to make future
improvements to this software (especially decreasing the
conversion time).
Image Quality
JPEG compression works best on images which are continuous
tone images, such as those produced by a scanner or digitizer.
Images which are drawn with paint programs typically do not
JPEG compress very well.
In addition, the best quality JPEG images result when you
start with 24 bit, undithered images. Unfortunately GIF does
not support 24 bit images; and most of the 8 bit GIF images
are dithered.
So, if you are using a scanner or digitizer to produce images,
you can get better compression ratios, and better quality
images, if you generate 24 bit Targa or TIFF files and then
convert them to JPEG files. You can't do this with GIF2JPG,
but you can with another Handmade product, Image Alchemy. See
the blatant ad below.
JPEG Information
If you would like more information on the JPEG format please
contact:
X3 Secretariat
Computer and Business Equipment Manufacturers Institute
311 First Street NW, Suite 500
Washington, DC 20001-2178
Blatant Ad for Image Alchemy
If your interest in image files extends beyond GIF and JPEG
you might be interested in Image Alchemy.
In addition to converting between over 15 different image file
formats, including GIF, JPEG, TIFF, Targa, PCX, Sun Raster,
Silicon Graphics Image, IFF/ILBM, PBM, and Encapsulated
Postscript, Alchemy will allow you to resize images, dither
images, and view images on a VGA monitor.
See the order form below for details on how to get a shareware
version.
Bugs and Support
If you have a question or think you found a bug in GIF2JPG or
JPG2GIF don't hesitate to contact us. We prefer to be reached
by email at the addresses listed on the front page of this
manual (we apologize for not having a BBS you can call; we
will soon). You may also fax us or call us during normal
business hours (we are on the West Coast).
By the way, contact us even if you have not registered,
because in addition to wanting to know about potential bugs,
we figure the best way to encourage registrations is to
demonstrate that we care about our customers.
Trademarks
GIF2JPG, JPG2GIF, and Image Alchemy are trademarks of Handmade
Software, Inc.
All other products or services mentioned are trademarks,
registered trademarks, or service marks of their respective
companies or organizations.
Disclaimer
Handmade Software, Inc. makes no warranty of any kind, either
expressed or implied, including but not limited to implied
warranties of merchantability and fitness for a particular
purpose.
In no event shall Handmade Software, Inc. be liable for any
errors contained herein or for incidental or consequential
damages in connection with the furnishing, performance, or use
of the GIF2JPG or JPG2GIF products or documentation.
JPG2GIF and GIF2JPG 1.41 Order Form
Send to: Handmade Software, Inc.
15951 Los Gatos Blvd., Suite 7
Los Gatos, CA 95032
Qty Description Price Total
_____ JPG2GIF & GIF2JPG for IBM PC $20.00 __________
_____ Image Alchemy -- Shareware version $2.00 __________
Sub-Total: __________
California Residents add applicable sales tax __________
Total __________
Circle Disk size: 3 1/2" 5 1/4"
Circle Payment form: Check MC Visa Amex
Card #:______________________________________ Exp. Date: ____________
Signature: _____________________________________________________
Name: ___________________________________________________________
Address: ________________________________________________________
________________________________________________________
City: ___________________________ State: _________ Zip: _________
Phone: (______) ________________ Fax: (______) ________________
Phone number of BBS you got this program from: __________________
Name of BBS: ____________________________________________________