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LICENSE.txt
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Tencent is pleased to support the open source community by making tgfx available.
Copyright (C) 2024 THL A29 Limited, a Tencent company. All rights reserved. The below software in this distribution may have been modified by THL A29 Limited ("Tencent Modifications"). All Tencent Modifications are Copyright (C) THL A29 Limited.
tgfx is licensed under the BSD 3-Clause License except for the third-party components listed below.
Terms of the BSD 3-Clause License:
--------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Other dependencies and licenses:
Open Source Software Licensed under the The FreeType Project LICENSE and Other Licenses of the Third-Party Components therein:
--------------------------------------------------------------------
1. freetype
Copyright (C) 2006-2022 by
David Turner, Robert Wilhelm, and Werner Lemberg.
Terms of the The FreeType Project LICENSE:
--------------------------------------------------------------------
The FreeType Project LICENSE
----------------------------
2006-Jan-27
Copyright 1996-2002, 2006 by
David Turner, Robert Wilhelm, and Werner Lemberg
Introduction
============
The FreeType Project is distributed in several archive packages;
some of them may contain, in addition to the FreeType font engine,
various tools and contributions which rely on, or relate to, the
FreeType Project.
This license applies to all files found in such packages, and
which do not fall under their own explicit license. The license
affects thus the FreeType font engine, the test programs,
documentation and makefiles, at the very least.
This license was inspired by the BSD, Artistic, and IJG
(Independent JPEG Group) licenses, which all encourage inclusion
and use of free software in commercial and freeware products
alike. As a consequence, its main points are that:
o We don't promise that this software works. However, we will be
interested in any kind of bug reports. (`as is' distribution)
o You can use this software for whatever you want, in parts or
full form, without having to pay us. (`royalty-free' usage)
o You may not pretend that you wrote this software. If you use
it, or only parts of it, in a program, you must acknowledge
somewhere in your documentation that you have used the
FreeType code. (`credits')
We specifically permit and encourage the inclusion of this
software, with or without modifications, in commercial products.
We disclaim all warranties covering The FreeType Project and
assume no liability related to The FreeType Project.
Finally, many people asked us for a preferred form for a
credit/disclaimer to use in compliance with this license. We thus
encourage you to use the following text:
"""
Portions of this software are copyright © <year> The FreeType
Project (www.freetype.org). All rights reserved.
"""
Please replace <year> with the value from the FreeType version you
actually use.
Legal Terms
===========
0. Definitions
--------------
Throughout this license, the terms `package', `FreeType Project',
and `FreeType archive' refer to the set of files originally
distributed by the authors (David Turner, Robert Wilhelm, and
Werner Lemberg) as the `FreeType Project', be they named as alpha,
beta or final release.
`You' refers to the licensee, or person using the project, where
`using' is a generic term including compiling the project's source
code as well as linking it to form a `program' or `executable'.
This program is referred to as `a program using the FreeType
engine'.
This license applies to all files distributed in the original
FreeType Project, including all source code, binaries and
documentation, unless otherwise stated in the file in its
original, unmodified form as distributed in the original archive.
If you are unsure whether or not a particular file is covered by
this license, you must contact us to verify this.
The FreeType Project is copyright (C) 1996-2000 by David Turner,
Robert Wilhelm, and Werner Lemberg. All rights reserved except as
specified below.
1. No Warranty
--------------
THE FREETYPE PROJECT IS PROVIDED `AS IS' WITHOUT WARRANTY OF ANY
KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE. IN NO EVENT WILL ANY OF THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY DAMAGES CAUSED BY THE USE OR THE INABILITY TO
USE, OF THE FREETYPE PROJECT.
2. Redistribution
-----------------
This license grants a worldwide, royalty-free, perpetual and
irrevocable right and license to use, execute, perform, compile,
display, copy, create derivative works of, distribute and
sublicense the FreeType Project (in both source and object code
forms) and derivative works thereof for any purpose; and to
authorize others to exercise some or all of the rights granted
herein, subject to the following conditions:
o Redistribution of source code must retain this license file
(`FTL.TXT') unaltered; any additions, deletions or changes to
the original files must be clearly indicated in accompanying
documentation. The copyright notices of the unaltered,
original files must be preserved in all copies of source
files.
o Redistribution in binary form must provide a disclaimer that
states that the software is based in part of the work of the
FreeType Team, in the distribution documentation. We also
encourage you to put an URL to the FreeType web page in your
documentation, though this isn't mandatory.
These conditions apply to any software derived from or based on
the FreeType Project, not just the unmodified files. If you use
our work, you must acknowledge us. However, no fee need be paid
to us.
3. Advertising
--------------
Neither the FreeType authors and contributors nor you shall use
the name of the other for commercial, advertising, or promotional
purposes without specific prior written permission.
We suggest, but do not require, that you use one or more of the
following phrases to refer to this software in your documentation
or advertising materials: `FreeType Project', `FreeType Engine',
`FreeType library', or `FreeType Distribution'.
As you have not signed this license, you are not required to
accept it. However, as the FreeType Project is copyrighted
material, only this license, or another one contracted with the
authors, grants you the right to use, distribute, and modify it.
Therefore, by using, distributing, or modifying the FreeType
Project, you indicate that you understand and accept all the terms
of this license.
4. Contacts
-----------
There are two mailing lists related to FreeType:
Discusses general use and applications of FreeType, as well as
future and wanted additions to the library and distribution.
If you are looking for support, start in this list if you
haven't found anything to help you in the documentation.
Discusses bugs, as well as engine internals, design issues,
specific licenses, porting, etc.
Our home page can be found at
https://www.freetype.org
--- end of FTL.TXT ---
For the license of other third party components, please refer to the following URL:
https://skia.googlesource.com/third_party/freetype2.git/+/refs/heads/master/LICENSE.TXT
Open Source Software Licensed under the libpng license:
--------------------------------------------------------------------
1. libpng
Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson
Terms of the libpng license:
--------------------------------------------------------------------
This copy of the libpng notices is provided for your convenience. In case of
any discrepancy between this copy and the notices in the file png.h that is
included in the libpng distribution, the latter shall prevail.
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
If you modify libpng you may insert additional notices immediately following
this sentence.
This code is released under the libpng license.
libpng versions 1.0.7, July 1, 2000 through 1.6.33, September 28, 2017 are
Copyright (c) 2000-2002, 2004, 2006-2017 Glenn Randers-Pehrson, are
derived from libpng-1.0.6, and are distributed according to the same
disclaimer and license as libpng-1.0.6 with the following individuals
added to the list of Contributing Authors:
Simon-Pierre Cadieux
Eric S. Raymond
Mans Rullgard
Cosmin Truta
Gilles Vollant
James Yu
Mandar Sahastrabuddhe
Google Inc.
Vadim Barkov
and with the following additions to the disclaimer:
There is no warranty against interference with your enjoyment of the
library or against infringement. There is no warranty that our
efforts or the library will fulfill any of your particular purposes
or needs. This library is provided with all faults, and the entire
risk of satisfactory quality, performance, accuracy, and effort is with
the user.
Some files in the "contrib" directory and some configure-generated
files that are distributed with libpng have other copyright owners and
are released under other open source licenses.
libpng versions 0.97, January 1998, through 1.0.6, March 20, 2000, are
Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
libpng-0.96, and are distributed according to the same disclaimer and
license as libpng-0.96, with the following individuals added to the list
of Contributing Authors:
Tom Lane
Glenn Randers-Pehrson
Willem van Schaik
libpng versions 0.89, June 1996, through 0.96, May 1997, are
Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
and are distributed according to the same disclaimer and license as
libpng-0.88, with the following individuals added to the list of
Contributing Authors:
John Bowler
Kevin Bracey
Sam Bushell
Magnus Holmgren
Greg Roelofs
Tom Tanner
Some files in the "scripts" directory have other copyright owners
but are released under this license.
libpng versions 0.5, May 1995, through 0.88, January 1996, are
Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
For the purposes of this copyright and license, "Contributing Authors"
is defined as the following set of individuals:
Andreas Dilger
Dave Martindale
Guy Eric Schalnat
Paul Schmidt
Tim Wegner
The PNG Reference Library is supplied "AS IS". The Contributing Authors
and Group 42, Inc. disclaim all warranties, expressed or implied,
including, without limitation, the warranties of merchantability and of
fitness for any purpose. The Contributing Authors and Group 42, Inc.
assume no liability for direct, indirect, incidental, special, exemplary,
or consequential damages, which may result from the use of the PNG
Reference Library, even if advised of the possibility of such damage.
Permission is hereby granted to use, copy, modify, and distribute this
source code, or portions hereof, for any purpose, without fee, subject
to the following restrictions:
1. The origin of this source code must not be misrepresented.
2. Altered versions must be plainly marked as such and must not
be misrepresented as being the original source.
3. This Copyright notice may not be removed or altered from any
source or altered source distribution.
The Contributing Authors and Group 42, Inc. specifically permit, without
fee, and encourage the use of this source code as a component to
supporting the PNG file format in commercial products. If you use this
source code in a product, acknowledgment is not required but would be
appreciated.
END OF COPYRIGHT NOTICE, DISCLAIMER, and LICENSE.
TRADEMARK:
The name "libpng" has not been registered by the Copyright owner
as a trademark in any jurisdiction. However, because libpng has
been distributed and maintained world-wide, continually since 1995,
the Copyright owner claims "common-law trademark protection" in any
jurisdiction where common-law trademark is recognized.
OSI CERTIFICATION:
Libpng is OSI Certified Open Source Software. OSI Certified Open Source is
a certification mark of the Open Source Initiative. OSI has not addressed
the additional disclaimers inserted at version 1.0.7.
EXPORT CONTROL:
The Copyright owner believes that the Export Control Classification
Number (ECCN) for libpng is EAR99, which means not subject to export
controls or International Traffic in Arms Regulations (ITAR) because
it is open source, publicly available software, that does not contain
any encryption software. See the EAR, paragraphs 734.3(b)(3) and
734.7(b).
Glenn Randers-Pehrson
glennrp at users.sourceforge.net
September 28, 2017
Open Source Software Licensed under the BSD 3-Clause License:
The below software in this distribution may have been modified by THL A29 Limited ("Tencent Modifications"). All Tencent Modifications are Copyright (C) 2024 THL A29 Limited.
--------------------------------------------------------------------
1. libwebp
Copyright (c) 2010, Google Inc. All rights reserved.
2. pathKit
Copyright (c) 2011 Google Inc. All rights reserved.
3. skcms
Copyright 2018 Google Inc.
4. tracy
Copyright (c) 2017-2024, Bartosz Taudul <[email protected]>
All rights reserved.
Terms of the BSD 3-Clause License:
--------------------------------------------------------------------
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Open Source Software Licensed under the IJG License and Other Licenses of the Third-Party Components therein:
--------------------------------------------------------------------
1. libjpeg-turbo
Copyright (C) 1991-1996, Thomas G. Lane.
Copyright (C) 2017, D. R. Commander.
Terms of the IJG License:
--------------------------------------------------------------------
The Independent JPEG Group's JPEG software
==========================================
This distribution contains a 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
(also 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.
FILE FORMAT WARS Software *not* to get.
TO DO Plans for future IJG releases.
Other documentation files in the distribution are:
User documentation:
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.txt Sample code for calling the JPEG library.
structure.txt Overview of the JPEG library's internal structure.
coderules.txt Coding style rules --- please read if you contribute code.
Please read at least 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. JPEG's strong suit is compressing
photographic images or other types of images that have smooth color and
brightness transitions between neighboring pixels. Images with sharp lines or
other abrupt features may not compress well with JPEG, and a higher JPEG
quality may have to be used to avoid visible compression artifacts with such
images.
JPEG is lossy, meaning that the output pixels are not necessarily identical to
the input pixels. However, on photographic content and other "smooth" images,
very good compression ratios can be obtained with no visible compression
artifacts, and extremely high compression ratios are possible if you are
willing to sacrifice image quality (by reducing the "quality" setting in the
compressor.)
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 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.
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 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).
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.
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. JFIF version 1 has been adopted as ISO/IEC 10918-5 (05/2013) and
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
https://www.iso.org/standard/54989.html and http://www.itu.int/rec/T-REC-T.871.
A PDF file of the older JFIF 1.02 specification 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".
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 [email protected]
with body
send usenet/news.answers/jpeg-faq/part1
send usenet/news.answers/jpeg-faq/part2
FILE FORMAT COMPATIBILITY
=========================
This software implements ITU T.81 | ISO/IEC 10918 with some extensions from
ITU T.871 | ISO/IEC 10918-5 (JPEG File Interchange Format-- see REFERENCES).
Informally, the term "JPEG image" or "JPEG file" most often refers to JFIF or
a subset thereof, but there are other formats containing the name "JPEG" that
are incompatible with the DCT-based JPEG standard or with JFIF (for instance,
JPEG 2000 and JPEG XR). This software therefore does not support these
formats. Indeed, one of the original reasons for developing this free software
was to help force convergence on a common, interoperable format standard for
JPEG files.
JFIF is a minimal or "low end" representation. TIFF/JPEG (TIFF revision 6.0 as
modified by TIFF Technical Note #2) can be used for "high end" applications
that need to record a lot of additional data about an image.
TO DO
=====
Please send bug reports, offers of help, etc. to [email protected].
For the license of other third party components, please refer to the following URL:
https://github.com/libjpeg-turbo/libjpeg-turbo/blob/2.0.0/LICENSE.md
Open Source Software Licensed under the Zlib License:
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Permission is granted to anyone to use this software for any purpose,
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Jean-loup Gailly Mark Adler
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