Remove libjpeg and libjpeg_turbo.

third_party/libjpeg/README

-The Independent JPEG Group's JPEG software
-==========================================
-
-README for release 6b of 27-Mar-1998
-====================================
-
-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, Jim Boucher,
-Lee Crocker, Julian Minguillon, Luis Ortiz, George Phillips, Davide Rossi,
-Guido Vollbeding, 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) 1991-1998, 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 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,
-ltconfig, ltmain.sh).  Another support script, install-sh, is copyright
-by M.I.T. but is also 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.
-
-The IJG distribution formerly included code to read and write GIF files.
-To avoid entanglement with the Unisys LZW patent, 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.
-
-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://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 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 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 or ITU.  (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 USA, 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 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.
-
-Some extensions to the original JPEG standard are defined in JPEG Part 3,
-a newer ISO standard numbered ISO/IEC IS 10918-3 and ITU-T T.84.  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 by FTP at
-ftp://ftp.uu.net/graphics/jpeg/jfif.ps.gz.  There is also a plain text
-version at ftp://ftp.uu.net/graphics/jpeg/jfif.txt.gz, but it is missing
-the figures.
-
-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 ftp.sgi.com or
-from ftp://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 ftp://ftp.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 ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz.  If you don't have
-direct Internet 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.  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://ftp.simtel.net/pub/simtelnet/msdos/graphics/), or
-on CompuServe in the Graphics Support forum (GO CIS: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.misc, news.answers, and other groups.
-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
-
-
-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 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, thus making cjpeg/djpeg considerably more useful.  The latest
-version is distributed by the NetPBM group, and is available from numerous
-sites, notably ftp://wuarchive.wustl.edu/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 ftp://havefun.stanford.edu/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.  (On the other hand, it doesn't do progressive JPEG.)
-
-
-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
-=====
-
-The major thrust for v7 will probably be improvement of visual quality.
-The current method for scaling the quantization tables is known not to be
-very good at low Q values.  We also intend to investigate block boundary
-smoothing, "poor man's variable quantization", and other means of improving
-quality-vs-file-size performance without sacrificing compatibility.
-
-In future versions, we are considering supporting some of the upcoming JPEG
-Part 3 extensions --- principally, variable quantization and the SPIFF file
-format.
-
-As always, speeding things up is of great interest.
-
-Please send bug reports, offers of help, etc. to jpeg-info@uunet.uu.net.