--- /dev/null
+The Independent JPEG Group's JPEG software
+==========================================
+
+README for release 9b of 17-Jan-2016
+====================================
+
+This distribution contains the ninth 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.
+
+This software is the work of Tom Lane, Guido Vollbeding, Philip Gladstone,
+Bill Allombert, Jim Boucher, Lee Crocker, Bob Friesenhahn, Ben Jackson,
+Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi, Ge' Weijers,
+and other members of the Independent JPEG Group.
+
+IJG is not affiliated with the ISO/IEC JTC1/SC29/WG1 standards committee
+(previously known as JPEG, together with ITU-T SG16).
+
+
+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.
+ACKNOWLEDGMENTS Special thanks.
+FILE FORMAT WARS Software *not* to get.
+TO DO Plans for future IJG releases.
+
+Other documentation files in the distribution are:
+
+User documentation:
+ install.txt How to configure and install the IJG software.
+ usage.txt Usage instructions for cjpeg, djpeg, jpegtran,
+ rdjpgcom, and wrjpgcom.
+ *.1 Unix-style man pages for programs (same info as usage.txt).
+ wizard.txt Advanced usage instructions for JPEG wizards only.
+ change.log Version-to-version change highlights.
+Programmer and internal documentation:
+ libjpeg.txt How to use the JPEG library in your own programs.
+ example.c Sample code for calling the JPEG library.
+ structure.txt Overview of the JPEG library's internal structure.
+ filelist.txt Road map of IJG files.
+ coderules.txt Coding style rules --- please read if you contribute code.
+
+Please read at least the files install.txt and usage.txt. Some 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 encoding, decoding,
+and transcoding. JPEG (pronounced "jay-peg") is a standardized compression
+method for full-color and grayscale images.
+
+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.
+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) 1991-2016, Thomas G. Lane, Guido Vollbeding.
+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.
+
+
+The Unix configuration script "configure" was produced with GNU Autoconf.
+It is copyright by the Free Software Foundation but is freely distributable.
+The same holds for its supporting scripts (config.guess, config.sub,
+ltmain.sh). Another support script, install-sh, is copyright by X Consortium
+but is also freely distributable.
+
+The IJG distribution formerly included code to read and write GIF files.
+To avoid entanglement with the Unisys LZW patent (now expired), GIF reading
+support has been removed altogether, and the GIF writer has been simplified
+to produce "uncompressed GIFs". This technique does not use the LZW
+algorithm; the resulting GIF files are larger than usual, but are readable
+by all standard GIF decoders.
+
+
+REFERENCES
+==========
+
+We 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 PDF file containing a revised version of Wallace's article is
+available at http://www.ijg.org/files/Wallace.JPEG.pdf. 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 and Jean-loup Gailly, published by
+M&T Books (New York), 2nd ed. 1996, ISBN 1-55851-434-1. 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 currently available 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).
+Although this is by far the most detailed and comprehensive exposition of
+JPEG publicly available, we point out that it is still missing an explanation
+of the most essential properties and algorithms of the underlying DCT
+technology.
+If you think that you know about DCT-based JPEG after reading this book,
+then you are in delusion. The real fundamentals and corresponding potential
+of DCT-based JPEG are not publicly known so far, and that is the reason for
+all the mistaken developments taking place in the image coding domain.
+
+The original JPEG 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 numbers ISO/IEC IS
+10918-1, ITU-T T.81. Part 2 is titled "Digital Compression and Coding of
+Continuous-tone Still Images, Part 2: Compliance testing" and has document
+numbers ISO/IEC IS 10918-2, ITU-T T.83.
+IJG JPEG 8 introduced an implementation of the JPEG SmartScale extension
+which is specified in two documents: A contributed document at ITU and ISO
+with title "ITU-T JPEG-Plus Proposal for Extending ITU-T T.81 for Advanced
+Image Coding", April 2006, Geneva, Switzerland. The latest version of this
+document is Revision 3. And a contributed document ISO/IEC JTC1/SC29/WG1 N
+5799 with title "Evolution of JPEG", June/July 2011, Berlin, Germany.
+IJG JPEG 9 introduces a reversible color transform for improved lossless
+compression which is described in a contributed document ISO/IEC JTC1/SC29/
+WG1 N 6080 with title "JPEG 9 Lossless Coding", June/July 2012, Paris,
+France.
+
+The JPEG standard does not specify all details of an interchangeable file
+format. For the omitted details we follow the "JFIF" conventions, version 2.
+JFIF version 1 has been adopted as Recommendation ITU-T T.871 (05/2011) :
+Information technology - Digital compression and coding of continuous-tone
+still images: JPEG File Interchange Format (JFIF). It is available as a
+free download in PDF file format from http://www.itu.int/rec/T-REC-T.871.
+A PDF file of the older JFIF document is available at
+http://www.w3.org/Graphics/JPEG/jfif3.pdf.
+
+The TIFF 6.0 file format specification can be obtained by FTP from
+ftp://ftp.sgi.com/graphics/tiff/TIFF6.ps.gz. 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
+http://www.ijg.org/files/. 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.
+
+
+ARCHIVE LOCATIONS
+=================
+
+The "official" archive site for this software is www.ijg.org.
+The most recent released version can always be found there in
+directory "files". This particular version will be archived as
+http://www.ijg.org/files/jpegsrc.v9b.tar.gz, and in Windows-compatible
+"zip" archive format as http://www.ijg.org/files/jpegsr9b.zip.
+
+The JPEG FAQ (Frequently Asked Questions) article is a source of some
+general information about JPEG.
+It is available on the World Wide Web at http://www.faqs.org/faqs/jpeg-faq/
+and other news.answers archive sites, including the official news.answers
+archive at rtfm.mit.edu: ftp://rtfm.mit.edu/pub/usenet/news.answers/jpeg-faq/.
+If you don't have Web or FTP access, 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
+
+
+ACKNOWLEDGMENTS
+===============
+
+Thank to Juergen Bruder for providing me with a copy of the common DCT
+algorithm article, only to find out that I had come to the same result
+in a more direct and comprehensible way with a more generative approach.
+
+Thank to Istvan Sebestyen and Joan L. Mitchell for inviting me to the
+ITU JPEG (Study Group 16) meeting in Geneva, Switzerland.
+
+Thank to Thomas Wiegand and Gary Sullivan for inviting me to the
+Joint Video Team (MPEG & ITU) meeting in Geneva, Switzerland.
+
+Thank to Thomas Richter and Daniel Lee for inviting me to the
+ISO/IEC JTC1/SC29/WG1 (previously known as JPEG, together with ITU-T SG16)
+meeting in Berlin, Germany.
+
+Thank to John Korejwa and Massimo Ballerini for inviting me to
+fruitful consultations in Boston, MA and Milan, Italy.
+
+Thank to Hendrik Elstner, Roland Fassauer, Simone Zuck, Guenther
+Maier-Gerber, Walter Stoeber, Fred Schmitz, and Norbert Braunagel
+for corresponding business development.
+
+Thank to Nico Zschach and Dirk Stelling of the technical support team
+at the Digital Images company in Halle for providing me with extra
+equipment for configuration tests.
+
+Thank to Richard F. Lyon (then of Foveon Inc.) for fruitful
+communication about JPEG configuration in Sigma Photo Pro software.
+
+Thank to Andrew Finkenstadt for hosting the ijg.org site.
+
+Last but not least special thank to Thomas G. Lane for the original
+design and development of this singular software package.
+
+
+FILE FORMAT WARS
+================
+
+The ISO/IEC JTC1/SC29/WG1 standards committee (previously known as JPEG,
+together with ITU-T SG16) currently promotes different formats containing
+the name "JPEG" which is misleading because these formats are incompatible
+with original DCT-based JPEG and are based on faulty technologies.
+IJG therefore does not and will not support such momentary mistakes
+(see REFERENCES).
+There exist also distributions under the name "OpenJPEG" promoting such
+kind of formats which is misleading because they don't support original
+JPEG images.
+We have no sympathy for the promotion of inferior formats. Indeed, one of
+the original reasons for developing this free software was to help force
+convergence on common, interoperable format standards for JPEG files.
+Don't use an incompatible file format!
+(In any case, our decoder will remain capable of reading existing JPEG
+image files indefinitely.)
+
+The ISO committee pretends to be "responsible for the popular JPEG" in their
+public reports which is not true because they don't respond to actual
+requirements for the maintenance of the original JPEG specification.
+Furthermore, the ISO committee pretends to "ensure interoperability" with
+their standards which is not true because their "standards" support only
+application-specific and proprietary use cases and contain mathematically
+incorrect code.
+
+There are currently different distributions in circulation containing the
+name "libjpeg" which is misleading because they don't have the features and
+are incompatible with formats supported by actual IJG libjpeg distributions.
+One of those fakes is released by members of the ISO committee and just uses
+the name of libjpeg for misdirection of people, similar to the abuse of the
+name JPEG as described above, while having nothing in common with actual IJG
+libjpeg distributions and containing mathematically incorrect code.
+The other one claims to be a "derivative" or "fork" of the original libjpeg,
+but violates the license conditions as described under LEGAL ISSUES above
+and violates basic C programming properties.
+We have no sympathy for the release of misleading, incorrect and illegal
+distributions derived from obsolete code bases.
+Don't use an obsolete code base!
+
+According to the UCC (Uniform Commercial Code) law, IJG has the lawful and
+legal right to foreclose on certain standardization bodies and other
+institutions or corporations that knowingly perform substantial and
+systematic deceptive acts and practices, fraud, theft, and damaging of the
+value of the people of this planet without their knowing, willing and
+intentional consent.
+The titles, ownership, and rights of these institutions and all their assets
+are now duly secured and held in trust for the free people of this planet.
+People of the planet, on every country, may have a financial interest in
+the assets of these former principals, agents, and beneficiaries of the
+foreclosed institutions and corporations.
+IJG asserts what is: that each man, woman, and child has unalienable value
+and rights granted and deposited in them by the Creator and not any one of
+the people is subordinate to any artificial principality, corporate fiction
+or the special interest of another without their appropriate knowing,
+willing and intentional consent made by contract or accommodation agreement.
+IJG expresses that which already was.
+The people have already determined and demanded that public administration
+entities, national governments, and their supporting judicial systems must
+be fully transparent, accountable, and liable.
+IJG has secured the value for all concerned free people of the planet.
+
+A partial list of foreclosed institutions and corporations ("Hall of Shame")
+is currently prepared and will be published later.
+
+
+TO DO
+=====
+
+Version 9 is the second release of a new generation JPEG standard
+to overcome the limitations of the original JPEG specification,
+and is the first true source reference JPEG codec.
+More features are being prepared for coming releases...
+
+Please send bug reports, offers of help, etc. to jpeg-info@jpegclub.org.
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