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apps2/!ChangeFSI/btpc/READMEJ

This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.

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File contents
BTPC uses the Independent JPEG Group's JPEG software in the file colmap.C only.
IJG require that their README file be distributed with any modified version of
their code. So here it is:

==========================================================================

The Independent JPEG Group's JPEG software
==========================================

README for release 6 of 2-Aug-95
================================

This distribution contains the sixth public release of the Independent JPEG
Group's free JPEG software.  You are welcome to redistribute this software and
to use it for any purpose, subject to the conditions under LEGAL ISSUES, below.

Serious users of this software (particularly those incorporating it into
larger programs) should contact IJG at jpeg-info@uunet.uu.net to be added to
our electronic mailing list.  Mailing list members are notified of updates
and have a chance to participate in technical discussions, etc.

This software is the work of Tom Lane, Philip Gladstone, Luis Ortiz, Jim
Boucher, Lee Crocker, Julian Minguillon, George Phillips, Davide Rossi,
Ge' Weijers, and other members of the Independent JPEG Group.

IJG is not affiliated with the official ISO JPEG standards committee.


DOCUMENTATION ROADMAP
=====================

This file contains the following sections:

OVERVIEW            General description of JPEG and the IJG software.
LEGAL ISSUES        Copyright, lack of warranty, terms of distribution.
REFERENCES          Where to learn more about JPEG.
ARCHIVE LOCATIONS   Where to find newer versions of this software.
RELATED SOFTWARE    Other stuff you should get.
FILE FORMAT WARS    Software *not* to get.
TO DO               Plans for future IJG releases.

Other documentation files in the distribution are:

User documentation:
  install.doc       How to configure and install the IJG software.
  usage.doc         Usage instructions for cjpeg, djpeg, jpegtran,
                    rdjpgcom, and wrjpgcom.
  *.1               Unix-style man pages for programs (same info as usage.doc).
  wizard.doc        Advanced usage instructions for JPEG wizards only.
  change.log        Version-to-version change highlights.
Programmer and internal documentation:
  libjpeg.doc       How to use the JPEG library in your own programs.
  example.c         Sample code for calling the JPEG library.
  structure.doc     Overview of the JPEG library's internal structure.
  filelist.doc      Road map of IJG files.
  coderules.doc     Coding style rules --- please read if you contribute code.

Please read at least the files install.doc and usage.doc.  Useful information
can also be found in the JPEG FAQ (Frequently Asked Questions) article.  See
ARCHIVE LOCATIONS below to find out where to obtain the FAQ article.

If you want to understand how the JPEG code works, we suggest reading one or
more of the REFERENCES, then looking at the documentation files (in roughly
the order listed) before diving into the code.


OVERVIEW
========

This package contains C software to implement JPEG image compression and
decompression.  JPEG (pronounced "jay-peg") is a standardized compression
method for full-color and gray-scale images.  JPEG is intended for compressing
"real-world" scenes; line drawings, cartoons and other non-realistic images
are not its strong suit.  JPEG is lossy, meaning that the output image is not
exactly identical to the input image.  Hence you must not use JPEG if you
have to have identical output bits.  However, on typical photographic images,
very good compression levels can be obtained with no visible change, and
remarkably high compression levels are possible if you can tolerate a
low-quality image.  For more details, see the references, or just experiment
with various compression settings.

This software implements JPEG baseline, extended-sequential, and progressive
compression processes.  Provision is made for supporting all variants of these
processes, although some uncommon parameter settings aren't implemented yet.
For legal reasons, we are not distributing code for the arithmetic-coding
variants of JPEG; see LEGAL ISSUES.  We have made no provision for supporting
the hierarchical or lossless processes defined in the standard.

We provide a set of library routines for reading and writing JPEG image files,
plus two sample applications "cjpeg" and "djpeg", which use the library to
perform conversion between JPEG and some other popular image file formats.
The library is intended to be reused in other applications.

In order to support file conversion and viewing software, we have included
considerable functionality beyond the bare JPEG coding/decoding capability;
for example, the color quantization modules are not strictly part of JPEG
decoding, but they are essential for output to colormapped file formats or
colormapped displays.  These extra functions can be compiled out of the
library if not required for a particular application.  We have also included
"jpegtran", a utility for lossless transcoding between different JPEG
processes, and "rdjpgcom" and "wrjpgcom", two simple applications for
inserting and extracting textual comments in JFIF files.

The emphasis in designing this software has been on achieving portability and
flexibility, while also making it fast enough to be useful.  In particular,
the software is not intended to be read as a tutorial on JPEG.  (See the
REFERENCES section for introductory material.)  Rather, it is intended to
be reliable, portable, industrial-strength code.  We do not claim to have
achieved that goal in every aspect of the software, but we strive for it.

We welcome the use of this software as a component of commercial products.
No royalty is required, but we do ask for an acknowledgement in product
documentation, as described under LEGAL ISSUES.


LEGAL ISSUES
============

In plain English:

1. We don't promise that this software works.  (But if you find any bugs,
   please let us know!)
2. You can use this software for whatever you want.  You don't have to pay us.
3. You may not pretend that you wrote this software.  If you use it in a
   program, you must acknowledge somewhere in your documentation that
   you've used the IJG code.

In legalese:

The authors make NO WARRANTY or representation, either express or implied,
with respect to this software, its quality, accuracy, merchantability, or
fitness for a particular purpose.  This software is provided "AS IS", and you,
its user, assume the entire risk as to its quality and accuracy.

This software is copyright (C) 1991, 1992, 1993, 1994, 1995, Thomas G. Lane.
All Rights Reserved except as specified below.

Permission is hereby granted to use, copy, modify, and distribute this
software (or portions thereof) for any purpose, without fee, subject to these
conditions:
(1) If any part of the source code for this software is distributed, then this
README file must be included, with this copyright and no-warranty notice
unaltered; and any additions, deletions, or changes to the original files
must be clearly indicated in accompanying documentation.
(2) If only executable code is distributed, then the accompanying
documentation must state that "this software is based in part on the work of
the Independent JPEG Group".
(3) Permission for use of this software is granted only if the user accepts
full responsibility for any undesirable consequences; the authors accept
NO LIABILITY for damages of any kind.

These conditions apply to any software derived from or based on the IJG code,
not just to the unmodified library.  If you use our work, you ought to
acknowledge us.

Permission is NOT granted for the use of any IJG author's name or company name
in advertising or publicity relating to this software or products derived from
it.  This software may be referred to only as "the Independent JPEG Group's
software".

We specifically permit and encourage the use of this software as the basis of
commercial products, provided that all warranty or liability claims are
assumed by the product vendor.


ansi2knr.c is included in this distribution by permission of L. Peter Deutsch,
sole proprietor of its copyright holder, Aladdin Enterprises of Menlo Park, CA.
ansi2knr.c is NOT covered by the above copyright and conditions, but instead
by the usual distribution terms of the Free Software Foundation; principally,
that you must include source code if you redistribute it.  (See the file
ansi2knr.c for full details.)  However, since ansi2knr.c is not needed as part
of any program generated from the IJG code, this does not limit you more than
the foregoing paragraphs do.

The configuration script "configure" was produced with GNU Autoconf.  It
is copyright by the Free Software Foundation but is freely distributable.

It appears that the arithmetic coding option of the JPEG spec is covered by
patents owned by IBM, AT&T, and Mitsubishi.  Hence arithmetic coding cannot
legally be used without obtaining one or more licenses.  For this reason,
support for arithmetic coding has been removed from the free JPEG software.
(Since arithmetic coding provides only a marginal gain over the unpatented
Huffman mode, it is unlikely that very many implementations will support it.)
So far as we are aware, there are no patent restrictions on the remaining
code.

WARNING: Unisys has begun to enforce their patent on LZW compression against
GIF encoders and decoders.  You will need a license from Unisys to use the
included rdgif.c or wrgif.c files in a commercial or shareware application.
At this time, Unisys is not enforcing their patent against freeware, so
distribution of this package remains legal.  However, we intend to remove
GIF support from the IJG package as soon as a suitable replacement format
becomes reasonably popular.

We are required to state that
    "The Graphics Interchange Format(c) is the Copyright property of
    CompuServe Incorporated.  GIF(sm) is a Service Mark property of
    CompuServe Incorporated."


REFERENCES
==========

We highly recommend reading one or more of these references before trying to
understand the innards of the JPEG software.

The best short technical introduction to the JPEG compression algorithm is
        Wallace, Gregory K.  "The JPEG Still Picture Compression Standard",
        Communications of the ACM, April 1991 (vol. 34 no. 4), pp. 30-44.
(Adjacent articles in that issue discuss MPEG motion picture compression,
applications of JPEG, and related topics.)  If you don't have the CACM issue
handy, a PostScript file containing a revised version of Wallace's article
is available at ftp.uu.net, graphics/jpeg/wallace.ps.gz.  The file (actually
a preprint for an article that appeared in IEEE Trans. Consumer Electronics)
omits the sample images that appeared in CACM, but it includes corrections
and some added material.  Note: the Wallace article is copyright ACM and
IEEE, and it may not be used for commercial purposes.

A somewhat less technical, more leisurely introduction to JPEG can be found in
"The Data Compression Book" by Mark Nelson, published by M&T Books (Redwood
City, CA), 1991, ISBN 1-55851-216-0.  This book provides good explanations and
example C code for a multitude of compression methods including JPEG.  It is
an excellent source if you are comfortable reading C code but don't know much
about data compression in general.  The book's JPEG sample code is far from
industrial-strength, but when you are ready to look at a full implementation,
you've got one here...

The best full description of JPEG is the textbook "JPEG Still Image Data
Compression Standard" by William B. Pennebaker and Joan L. Mitchell, published
by Van Nostrand Reinhold, 1993, ISBN 0-442-01272-1.  Price US$59.95, 638 pp.
The book includes the complete text of the ISO JPEG standards (DIS 10918-1
and draft DIS 10918-2).  This is by far the most complete exposition of JPEG
in existence, and we highly recommend it.

The JPEG standard itself is not available electronically; you must order a
paper copy through ISO.  (Unless you feel a need to own a certified official
copy, we recommend buying the Pennebaker and Mitchell book instead; it's much
cheaper and includes a great deal of useful explanatory material.)  In the US,
copies of the standard may be ordered from ANSI Sales at (212) 642-4900, or
from Global Engineering Documents at (800) 854-7179.  (ANSI doesn't take
credit card orders, but Global does.)  It's not cheap: as of 1992, ANSI was
charging $95 for Part 1 and $47 for Part 2, plus 7% shipping/handling.  The
standard is divided into two parts, Part 1 being the actual specification,
while Part 2 covers compliance testing methods.  Part 1 is titled "Digital
Compression and Coding of Continuous-tone Still Images, Part 1: Requirements
and guidelines" and has document number ISO/IEC IS 10918-1.  Part 2 is titled
"Digital Compression and Coding of Continuous-tone Still Images, Part 2:
Compliance testing" and has document number ISO/IEC IS 10918-2.

Extensions to the original JPEG standard are defined in Part 3, a new ISO
document.  Part 3 is undergoing ISO balloting and is expected to be approved
by the end of 1995.  IJG currently does not support any Part 3 extensions.

The JPEG standard does not specify all details of an interchangeable file
format.  For the omitted details we follow the "JFIF" conventions, revision
1.02.  A copy of the JFIF spec is available from:
        Literature Department
        C-Cube Microsystems, Inc.
        1778 McCarthy Blvd.
        Milpitas, CA 95035
        phone (408) 944-6300,  fax (408) 944-6314
A PostScript version of this document is available at ftp.uu.net, file
graphics/jpeg/jfif.ps.gz.  It can also be obtained by e-mail from the C-Cube
mail server, netlib@c3.pla.ca.us.  Send the message "send jfif_ps from jpeg"
to the server to obtain the JFIF document; send the message "help" if you have
trouble.

The TIFF 6.0 file format specification can be obtained by FTP from sgi.com
(192.48.153.1), file graphics/tiff/TIFF6.ps.Z; or you can order a printed
copy from Aldus Corp. at (206) 628-6593.  The JPEG incorporation scheme
found in the TIFF 6.0 spec of 3-June-92 has a number of serious problems.
IJG does not recommend use of the TIFF 6.0 design (TIFF Compression tag 6).
Instead, we recommend the JPEG design proposed by TIFF Technical Note #2
(Compression tag 7).  Copies of this Note can be obtained from sgi.com or
from ftp.uu.net:/graphics/jpeg/.  It is expected that the next revision of
the TIFF spec will replace the 6.0 JPEG design with the Note's design.
Although IJG's own code does not support TIFF/JPEG, the free libtiff library
uses our library to implement TIFF/JPEG per the Note.  libtiff is available
from sgi.com:/graphics/tiff/.


ARCHIVE LOCATIONS
=================

The "official" archive site for this software is ftp.uu.net (Internet
address 192.48.96.9).  The most recent released version can always be found
there in directory graphics/jpeg.  This particular version will be archived
as graphics/jpeg/jpegsrc.v6.tar.gz.  If you are on the Internet, you
can retrieve files from ftp.uu.net by standard anonymous FTP.  If you don't
have FTP access, UUNET's archives are also available via UUCP; contact
help@uunet.uu.net for information on retrieving files that way.

Numerous Internet sites maintain copies of the UUNET files; in particular,
you can probably find a copy at any site that archives comp.sources.misc
submissions.  However, only ftp.uu.net is guaranteed to have the latest
official version.

You can also obtain this software in DOS-compatible "zip" archive format from
the SimTel archives (ftp.coast.net:/SimTel/msdos/graphics/), or on CompuServe
in the GRAPHSUPPORT forum (GO GRAPHSUP), library 12 "JPEG Tools".  Again,
these versions may sometimes lag behind the ftp.uu.net release.

The JPEG FAQ (Frequently Asked Questions) article is a useful source of
general information about JPEG.  It is updated constantly and therefore is
not included in this distribution.  The FAQ is posted every two weeks to
Usenet newsgroups comp.graphics, news.answers, and other groups.  You can
always obtain the latest version from the news.answers archive at
rtfm.mit.edu.  By FTP, fetch /pub/usenet/news.answers/jpeg-faq/part1 and
.../part2.  If you don't have FTP, send e-mail to mail-server@rtfm.mit.edu
with body
        send usenet/news.answers/jpeg-faq/part1
        send usenet/news.answers/jpeg-faq/part2


RELATED SOFTWARE
================

Numerous viewing and image manipulation programs now support JPEG.  (Quite a
few of them use this library to do so.)  The JPEG FAQ described above lists
some of the more popular free and shareware viewers, and tells where to
obtain them on Internet.

If you are on a Unix machine, we highly recommend Jef Poskanzer's free
PBMPLUS image software, which provides many useful operations on PPM-format
image files.  In particular, it can convert PPM images to and from a wide
range of other formats.  You can obtain this package by FTP from ftp.x.org
(contrib/pbmplus*.tar.Z) or ftp.ee.lbl.gov (pbmplus*.tar.Z).  There is also
a newer update of this package called NETPBM, available from
wuarchive.wustl.edu under directory /graphics/graphics/packages/NetPBM/.
Unfortunately PBMPLUS/NETPBM is not nearly as portable as the IJG software
is; you are likely to have difficulty making it work on any non-Unix machine.

A different free JPEG implementation, written by the PVRG group at Stanford,
is available from havefun.stanford.edu in directory pub/jpeg.  This program
is designed for research and experimentation rather than production use;
it is slower, harder to use, and less portable than the IJG code, but it
is easier to read and modify.  Also, the PVRG code supports lossless JPEG,
which we do not.


FILE FORMAT WARS
================

Some JPEG programs produce files that are not compatible with our library.
The root of the problem is that the ISO JPEG committee failed to specify a
concrete file format.  Some vendors "filled in the blanks" on their own,
creating proprietary formats that no one else could read.  (For example, none
of the early commercial JPEG implementations for the Macintosh were able to
exchange compressed files.)

The file format we have adopted is called JFIF (see REFERENCES).  This format
has been agreed to by a number of major commercial JPEG vendors, and it has
become the de facto standard.  JFIF is a minimal or "low end" representation.
We recommend the use of TIFF/JPEG (TIFF revision 6.0 as modified by TIFF
Technical Note #2) for "high end" applications that need to record a lot of
additional data about an image.  TIFF/JPEG is fairly new and not yet widely
supported, unfortunately.

The upcoming JPEG Part 3 standard defines a file format called SPIFF.
SPIFF is interoperable with JFIF, in the sense that most JFIF decoders should
be able to read the most common variant of SPIFF.  SPIFF has some technical
advantages over JFIF, but its major claim to fame is simply that it is an
official standard rather than an informal one.  At this point it is unclear
whether SPIFF will supersede JFIF or whether JFIF will remain the de-facto
standard.  IJG intends to support SPIFF once the standard is frozen, but we
have not decided whether it should become our default output format or not.
(In any case, our decoder will remain capable of reading JFIF indefinitely.)

Various proprietary file formats incorporating JPEG compression also exist.
We have little or no sympathy for the existence of these formats.  Indeed,
one of the original reasons for developing this free software was to help
force convergence on common, open format standards for JPEG files.  Don't
use a proprietary file format!


TO DO
=====

In future versions, we are considering supporting some of the upcoming JPEG
Part 3 extensions --- principally, variable quantization and the SPIFF file
format.

Tuning the software for better behavior at low quality/high compression
settings is also of interest.  The current method for scaling the
quantization tables is known not to be very good at low Q values.

As always, speeding things up is high on our priority list.

Please send bug reports, offers of help, etc. to jpeg-info@uunet.uu.net.

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00000040  20 63 6f 6c 6d 61 70 2e  43 20 6f 6e 6c 79 2e 0a  | colmap.C only..|
00000050  49 4a 47 20 72 65 71 75  69 72 65 20 74 68 61 74  |IJG require that|
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000000c0  3d 3d 3d 3d 3d 3d 3d 3d  3d 3d 3d 3d 3d 3d 3d 3d  |================|
*
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00000160  41 44 4d 45 20 66 6f 72  20 72 65 6c 65 61 73 65  |ADME for release|
00000170  20 36 20 6f 66 20 32 2d  41 75 67 2d 39 35 0a 3d  | 6 of 2-Aug-95.=|
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00000340  20 4d 61 69 6c 69 6e 67  20 6c 69 73 74 20 6d 65  | Mailing list me|
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000003c0  74 68 65 20 77 6f 72 6b  20 6f 66 20 54 6f 6d 20  |the work of Tom |
000003d0  4c 61 6e 65 2c 20 50 68  69 6c 69 70 20 47 6c 61  |Lane, Philip Gla|
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00000400  20 4c 65 65 20 43 72 6f  63 6b 65 72 2c 20 4a 75  | Lee Crocker, Ju|
00000410  6c 69 61 6e 20 4d 69 6e  67 75 69 6c 6c 6f 6e 2c  |lian Minguillon,|
00000420  20 47 65 6f 72 67 65 20  50 68 69 6c 6c 69 70 73  | George Phillips|
00000430  2c 20 44 61 76 69 64 65  20 52 6f 73 73 69 2c 0a  |, Davide Rossi,.|
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000026f0  0a 0a 52 45 46 45 52 45  4e 43 45 53 0a 3d 3d 3d  |..REFERENCES.===|
00002700  3d 3d 3d 3d 3d 3d 3d 0a  0a 57 65 20 68 69 67 68  |=======..We high|
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000027e0  47 72 65 67 6f 72 79 20  4b 2e 20 20 22 54 68 65  |Gregory K.  "The|
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000032f0  4f 0a 64 6f 63 75 6d 65  6e 74 2e 20 20 50 61 72  |O.document.  Par|
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00003460  61 74 75 72 65 20 44 65  70 61 72 74 6d 65 6e 74  |ature Department|
00003470  0a 20 20 20 20 20 20 20  20 43 2d 43 75 62 65 20  |.        C-Cube |
00003480  4d 69 63 72 6f 73 79 73  74 65 6d 73 2c 20 49 6e  |Microsystems, In|
00003490  63 2e 0a 20 20 20 20 20  20 20 20 31 37 37 38 20  |c..        1778 |
000034a0  4d 63 43 61 72 74 68 79  20 42 6c 76 64 2e 0a 20  |McCarthy Blvd.. |
000034b0  20 20 20 20 20 20 20 4d  69 6c 70 69 74 61 73 2c  |       Milpitas,|
000034c0  20 43 41 20 39 35 30 33  35 0a 20 20 20 20 20 20  | CA 95035.      |
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000034e0  34 2d 36 33 30 30 2c 20  20 66 61 78 20 28 34 30  |4-6300,  fax (40|
000034f0  38 29 20 39 34 34 2d 36  33 31 34 0a 41 20 50 6f  |8) 944-6314.A Po|
00003500  73 74 53 63 72 69 70 74  20 76 65 72 73 69 6f 6e  |stScript version|
00003510  20 6f 66 20 74 68 69 73  20 64 6f 63 75 6d 65 6e  | of this documen|
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00003550  2f 6a 66 69 66 2e 70 73  2e 67 7a 2e 20 20 49 74  |/jfif.ps.gz.  It|
00003560  20 63 61 6e 20 61 6c 73  6f 20 62 65 20 6f 62 74  | can also be obt|
00003570  61 69 6e 65 64 20 62 79  20 65 2d 6d 61 69 6c 20  |ained by e-mail |
00003580  66 72 6f 6d 20 74 68 65  20 43 2d 43 75 62 65 0a  |from the C-Cube.|
00003590  6d 61 69 6c 20 73 65 72  76 65 72 2c 20 6e 65 74  |mail server, net|
000035a0  6c 69 62 40 63 33 2e 70  6c 61 2e 63 61 2e 75 73  |lib@c3.pla.ca.us|
000035b0  2e 20 20 53 65 6e 64 20  74 68 65 20 6d 65 73 73  |.  Send the mess|
000035c0  61 67 65 20 22 73 65 6e  64 20 6a 66 69 66 5f 70  |age "send jfif_p|
000035d0  73 20 66 72 6f 6d 20 6a  70 65 67 22 0a 74 6f 20  |s from jpeg".to |
000035e0  74 68 65 20 73 65 72 76  65 72 20 74 6f 20 6f 62  |the server to ob|
000035f0  74 61 69 6e 20 74 68 65  20 4a 46 49 46 20 64 6f  |tain the JFIF do|
00003600  63 75 6d 65 6e 74 3b 20  73 65 6e 64 20 74 68 65  |cument; send the|
00003610  20 6d 65 73 73 61 67 65  20 22 68 65 6c 70 22 20  | message "help" |
00003620  69 66 20 79 6f 75 20 68  61 76 65 0a 74 72 6f 75  |if you have.trou|
00003630  62 6c 65 2e 0a 0a 54 68  65 20 54 49 46 46 20 36  |ble...The TIFF 6|
00003640  2e 30 20 66 69 6c 65 20  66 6f 72 6d 61 74 20 73  |.0 file format s|
00003650  70 65 63 69 66 69 63 61  74 69 6f 6e 20 63 61 6e  |pecification can|
00003660  20 62 65 20 6f 62 74 61  69 6e 65 64 20 62 79 20  | be obtained by |
00003670  46 54 50 20 66 72 6f 6d  20 73 67 69 2e 63 6f 6d  |FTP from sgi.com|
00003680  0a 28 31 39 32 2e 34 38  2e 31 35 33 2e 31 29 2c  |.(192.48.153.1),|
00003690  20 66 69 6c 65 20 67 72  61 70 68 69 63 73 2f 74  | file graphics/t|
000036a0  69 66 66 2f 54 49 46 46  36 2e 70 73 2e 5a 3b 20  |iff/TIFF6.ps.Z; |
000036b0  6f 72 20 79 6f 75 20 63  61 6e 20 6f 72 64 65 72  |or you can order|
000036c0  20 61 20 70 72 69 6e 74  65 64 0a 63 6f 70 79 20  | a printed.copy |
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000036e0  20 61 74 20 28 32 30 36  29 20 36 32 38 2d 36 35  | at (206) 628-65|
000036f0  39 33 2e 20 20 54 68 65  20 4a 50 45 47 20 69 6e  |93.  The JPEG in|
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00003710  6d 65 0a 66 6f 75 6e 64  20 69 6e 20 74 68 65 20  |me.found in the |
00003720  54 49 46 46 20 36 2e 30  20 73 70 65 63 20 6f 66  |TIFF 6.0 spec of|
00003730  20 33 2d 4a 75 6e 65 2d  39 32 20 68 61 73 20 61  | 3-June-92 has a|
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00003750  75 73 20 70 72 6f 62 6c  65 6d 73 2e 0a 49 4a 47  |us problems..IJG|
00003760  20 64 6f 65 73 20 6e 6f  74 20 72 65 63 6f 6d 6d  | does not recomm|
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00003990  4f 43 41 54 49 4f 4e 53  0a 3d 3d 3d 3d 3d 3d 3d  |OCATIONS.=======|
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00003d60  32 20 22 4a 50 45 47 20  54 6f 6f 6c 73 22 2e 20  |2 "JPEG Tools". |
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00003e70  54 68 65 20 46 41 51 20  69 73 20 70 6f 73 74 65  |The FAQ is poste|
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00004d90  0a 66 6f 72 6d 61 74 2e  0a 0a 54 75 6e 69 6e 67  |.format...Tuning|
00004da0  20 74 68 65 20 73 6f 66  74 77 61 72 65 20 66 6f  | the software fo|
00004db0  72 20 62 65 74 74 65 72  20 62 65 68 61 76 69 6f  |r better behavio|
00004dc0  72 20 61 74 20 6c 6f 77  20 71 75 61 6c 69 74 79  |r at low quality|
00004dd0  2f 68 69 67 68 20 63 6f  6d 70 72 65 73 73 69 6f  |/high compressio|
00004de0  6e 0a 73 65 74 74 69 6e  67 73 20 69 73 20 61 6c  |n.settings is al|
00004df0  73 6f 20 6f 66 20 69 6e  74 65 72 65 73 74 2e 20  |so of interest. |
00004e00  20 54 68 65 20 63 75 72  72 65 6e 74 20 6d 65 74  | The current met|
00004e10  68 6f 64 20 66 6f 72 20  73 63 61 6c 69 6e 67 20  |hod for scaling |
00004e20  74 68 65 0a 71 75 61 6e  74 69 7a 61 74 69 6f 6e  |the.quantization|
00004e30  20 74 61 62 6c 65 73 20  69 73 20 6b 6e 6f 77 6e  | tables is known|
00004e40  20 6e 6f 74 20 74 6f 20  62 65 20 76 65 72 79 20  | not to be very |
00004e50  67 6f 6f 64 20 61 74 20  6c 6f 77 20 51 20 76 61  |good at low Q va|
00004e60  6c 75 65 73 2e 0a 0a 41  73 20 61 6c 77 61 79 73  |lues...As always|
00004e70  2c 20 73 70 65 65 64 69  6e 67 20 74 68 69 6e 67  |, speeding thing|
00004e80  73 20 75 70 20 69 73 20  68 69 67 68 20 6f 6e 20  |s up is high on |
00004e90  6f 75 72 20 70 72 69 6f  72 69 74 79 20 6c 69 73  |our priority lis|
00004ea0  74 2e 0a 0a 50 6c 65 61  73 65 20 73 65 6e 64 20  |t...Please send |
00004eb0  62 75 67 20 72 65 70 6f  72 74 73 2c 20 6f 66 66  |bug reports, off|
00004ec0  65 72 73 20 6f 66 20 68  65 6c 70 2c 20 65 74 63  |ers of help, etc|
00004ed0  2e 20 74 6f 20 6a 70 65  67 2d 69 6e 66 6f 40 75  |. to jpeg-info@u|
00004ee0  75 6e 65 74 2e 75 75 2e  6e 65 74 2e 0a           |unet.uu.net..|
00004eed

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