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|
====================COPYRIGHT====================
"Copyright (c) 2018-2023 Cosmin Truta" PNG_STRING_NEWLINE \
"Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson" \
PNG_STRING_NEWLINE \
"Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
"Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
PNG_STRING_NEWLINE \
"Portions Copyright (c) 2006-2007 Andrew Smith" PNG_STRING_NEWLINE \
"Portions Copyright (c) 2008-2023 Max Stepin" PNG_STRING_NEWLINE ;
#endif
====================COPYRIGHT====================
* Copyright (c) 1995-2023 The PNG Reference Library Authors.
* Copyright (c) 2018-2023 Cosmin Truta.
* Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
* Copyright (c) 1996-1997 Andreas Dilger.
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2013 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2013,2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2014,2016 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2014,2016,2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2014,2017 Glenn Randers-Pehrson
* Written by Mans Rullgard, 2011.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2016 Glenn Randers-Pehrson
* Written by Mandar Sahastrabuddhe, August 2016.
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2016-2017 Glenn Randers-Pehrson
* Written by Mike Klein and Matt Sarett
* Derived from arm/filter_neon_intrinsics.c
====================COPYRIGHT====================
* Copyright (c) 2018 Cosmin Truta
* Copyright (c) 2017 Glenn Randers-Pehrson
* Written by Vadim Barkov, 2017.
====================COPYRIGHT====================
* Copyright (c) 2018-2019 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018-2019 Cosmin Truta
* Copyright (c) 2017-2018 Arm Holdings. All rights reserved.
====================COPYRIGHT====================
* Copyright (c) 2018-2022 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2016,2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018-2022 Cosmin Truta
* Copyright (c) 2014,2016 Glenn Randers-Pehrson
* Written by Mans Rullgard, 2011.
====================COPYRIGHT====================
* Copyright (c) 2018-2023 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
* Copyright (c) 2018-2023 Cosmin Truta
* Copyright (c) 1998-2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
====================COPYRIGHT====================
Copyright (c) 2006-2007 Andrew Smith, Copyright (c) 2008-2023 Max Stepin,
and are delimited by "#ifdef PNG_APNG_SUPPORTED / #endif" directives
surrounding them in the modified libpng source files.
====================COPYRIGHT====================
Copyright (c) 2022 Cosmin Truta
Copyright (c) 1998-2002,2006-2016 Glenn Randers-Pehrson
This document is released under the libpng license.
For conditions of distribution and use, see the disclaimer
====================COPYRIGHT====================
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:
====================File: INSTALL====================
Installing libpng
Contents
I. Simple installation
II. Rebuilding the configure scripts
III. Using scripts/makefile*
IV. Using cmake
V. Directory structure
VI. Building with project files
VII. Building with makefiles
VIII. Configuring libpng for 16-bit platforms
IX. Configuring for DOS
X. Configuring for Medium Model
XI. Prepending a prefix to exported symbols
XII. Configuring for compiler xxx:
XIII. Removing unwanted object code
XIV. Enabling or disabling hardware optimizations
XV. Changes to the build and configuration of libpng in libpng-1.5.x
XVI. Setjmp/longjmp issues
XVII. Common linking failures
XVIII. Other sources of information about libpng
I. Simple installation
On Unix/Linux and similar systems, you can simply type
./configure [--prefix=/path]
make check
make install
and ignore the rest of this document. "/path" is the path to the directory
where you want to install the libpng "lib", "include", and "bin"
subdirectories.
If you downloaded a GIT clone, you will need to run ./autogen.sh before
running ./configure, to create "configure" and "Makefile.in" which are
not included in the GIT repository.
Note that "configure" is only included in the "*.tar" distributions and not
in the "*.zip" or "*.7z" distributions. If you downloaded one of those
distributions, see "Building with project files" or "Building with makefiles",
below.
II. Rebuilding the configure scripts
If configure does not work on your system, or if you have a need to
change configure.ac or Makefile.am, and you have a reasonably
up-to-date set of tools, running ./autogen.sh in a git clone before
running ./configure may fix the problem. To be really sure that you
aren't using any of the included pre-built scripts, especially if you
are building from a tar distribution instead of a git distribution,
do this:
./configure --enable-maintainer-mode
make maintainer-clean
./autogen.sh --maintainer --clean
./autogen.sh --maintainer
./configure [--prefix=/path] [other options]
make
make install
make check
III. Using scripts/makefile*
Instead, you can use one of the custom-built makefiles in the
"scripts" directory
cp scripts/pnglibconf.h.prebuilt pnglibconf.h
cp scripts/makefile.system makefile
make test
make install
The files that are presently available in the scripts directory
are listed and described in scripts/README.txt.
Or you can use one of the "projects" in the "projects" directory.
Before installing libpng, you must first install zlib, if it
is not already on your system. zlib can usually be found
wherever you got libpng; otherwise go to https://zlib.net/. You can
place zlib in the same directory as libpng or in another directory.
If your system already has a preinstalled zlib you will still need
to have access to the zlib.h and zconf.h include files that
correspond to the version of zlib that's installed.
If you wish to test with a particular zlib that is not first in the
standard library search path, put ZLIBLIB, ZLIBINC, CPPFLAGS, LDFLAGS,
and LD_LIBRARY_PATH in your environment before running "make test"
or "make distcheck":
ZLIBLIB=/path/to/lib export ZLIBLIB
ZLIBINC=/path/to/include export ZLIBINC
CPPFLAGS="-I$ZLIBINC" export CPPFLAGS
LDFLAGS="-L$ZLIBLIB" export LDFLAGS
LD_LIBRARY_PATH="$ZLIBLIB:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH
If you are using one of the makefile scripts, put ZLIBLIB and ZLIBINC
in your environment and type
make ZLIBLIB=$ZLIBLIB ZLIBINC=$ZLIBINC test
IV. Using cmake
If you want to use "cmake" (see www.cmake.org), type
cmake . -DCMAKE_INSTALL_PREFIX=/path
make
make install
As when using the simple configure method described above, "/path" points to
the installation directory where you want to put the libpng "lib", "include",
and "bin" subdirectories.
V. Directory structure
You can rename the directories that you downloaded (they
might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.8"
or "zlib128") so that you have directories called "zlib" and "libpng".
Your directory structure should look like this:
.. (the parent directory)
libpng (this directory)
INSTALL (this file)
README
*.h, *.c => libpng source files
CMakeLists.txt => "cmake" script
ci
ci_*.sh
configuration files:
configure.ac, configure, Makefile.am, Makefile.in,
autogen.sh, config.guess, ltmain.sh, missing, libpng.pc.in,
libpng-config.in, aclocal.m4, config.h.in, config.sub,
depcomp, install-sh, mkinstalldirs, test-pngtest.sh, etc.
contrib
arm-neon, conftest, examples, gregbook, libtests, pngminim,
pngminus, pngsuite, tools, visupng
projects
owatcom, visualc71, vstudio
scripts
makefile.*
*.def (module definition files)
etc.
pngtest.png
etc.
zlib
README, *.h, *.c, contrib, etc.
If the line endings in the files look funny, you may wish to get the other
distribution of libpng. It is available in both tar.gz (UNIX style line
endings) and zip (DOS style line endings) formats.
VI. Building with project files
If you are building libpng with Microsoft Visual Studio, you can enter
the directory projects\visualc71 or projects\vstudio and follow the
instructions in README.txt.
Otherwise, enter the zlib directory and follow the instructions in
zlib/README, then come back here and run "configure" or choose the
appropriate makefile in the scripts directory.
VII. Building with makefiles
Copy the file (or files) that you need from the
scripts directory into this directory, for example
UNIX example:
cp scripts/makefile.std Makefile
make
Windows example:
nmake -f scripts\makefile.vcwin32
Read the makefile to see if you need to change any source or
target directories to match your preferences.
Then read pnglibconf.dfa to see if you want to make any configuration
changes.
Then just run "make" which will create the libpng library in
this directory and "make test" which will run a quick test that reads
the "pngtest.png" file and writes a "pngout.png" file that should be
identical to it. Look for "9782 zero samples" in the output of the
test. For more confidence, you can run another test by typing
"pngtest pngnow.png" and looking for "289 zero samples" in the output.
Also, you can run "pngtest -m contrib/pngsuite/*.png" and compare
your output with the result shown in contrib/pngsuite/README.
Most of the makefiles used to allow you to run "make install" to put
the library in its final resting place, but that feature is no longer
supported. The only tested and supported manners to install libpng are
the conventional build and install procedures driven by the configure
script or by the CMake file.
VIII. Configuring for DOS and other 16-bit platforms
Officially, the support for 16-bit platforms has been removed.
For DOS users who only have access to the lower 640K, you will
have to limit zlib's memory usage via a png_set_compression_mem_level()
call. See zlib.h or zconf.h in the zlib library for more information.
You may be or may not be in luck if you target the "large" memory model,
but all the smaller models ("small", "compact" and "medium") are known
to be unworkable. For DOS users who have access beyond the lower 640K,
a "flat" 32-bit DOS model (such as DJGPP) is strongly recommended.
For DOS users who only have access to the lower 640K, you will have to
limit zlib's memory usage via a png_set_compression_mem_level() call.
You will also have to look into zconf.h to tell zlib (and thus libpng)
that it cannot allocate more than 64K at a time. Even if you can, the
memory won't be accessible. Therefore, you should limit zlib and libpng
to 64K by defining MAXSEG_64K.
IX. Prepending a prefix to exported symbols
Starting with libpng-1.6.0, you can configure libpng (when using the
"configure" script) to prefix all exported symbols by means of the
configuration option "--with-libpng-prefix=FOO_", where FOO_ can be any
string beginning with a letter and containing only uppercase
and lowercase letters, digits, and the underscore (i.e., a C language
identifier). This creates a set of macros in pnglibconf.h, so this is
transparent to applications; their function calls get transformed by
the macros to use the modified names.
X. Configuring for compiler xxx:
All includes for libpng are in pngconf.h. If you need to add, change
or delete an include, this is the place to do it.
The includes that are not needed outside libpng are placed in pngpriv.h,
which is only used by the routines inside libpng itself.
The files in libpng proper only include pngpriv.h and png.h, which
in turn includes pngconf.h and, as of libpng-1.5.0, pnglibconf.h.
As of libpng-1.5.0, pngpriv.h also includes three other private header
files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
that previously appeared in the public headers.
XI. Removing unwanted object code
There are a bunch of #define's in pngconf.h that control what parts of
libpng are compiled. All the defines end in _SUPPORTED. If you are
never going to use a capability, you can change the #define to #undef
before recompiling libpng and save yourself code and data space, or
you can turn off individual capabilities with defines that begin with
"PNG_NO_".
In libpng-1.5.0 and later, the #define's are in pnglibconf.h instead.
You can also turn all of the transforms and ancillary chunk capabilities
off en masse with compiler directives that define
PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS,
or all four, along with directives to turn on any of the capabilities that
you do want. The PNG_NO_READ[or WRITE]_TRANSFORMS directives disable the
extra transformations but still leave the library fully capable of reading
and writing PNG files with all known public chunks. Use of the
PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS directive produces a library
that is incapable of reading or writing ancillary chunks. If you are
not using the progressive reading capability, you can turn that off
with PNG_NO_PROGRESSIVE_READ (don't confuse this with the INTERLACING
capability, which you'll still have).
All the reading and writing specific code are in separate files, so the
linker should only grab the files it needs. However, if you want to
make sure, or if you are building a stand alone library, all the
reading files start with "pngr" and all the writing files start with "pngw".
The files that don't match either (like png.c, pngtrans.c, etc.)
are used for both reading and writing, and always need to be included.
The progressive reader is in pngpread.c
If you are creating or distributing a dynamically linked library (a .so
or DLL file), you should not remove or disable any parts of the library,
as this will cause applications linked with different versions of the
library to fail if they call functions not available in your library.
The size of the library itself should not be an issue, because only
those sections that are actually used will be loaded into memory.
XII. Enabling or disabling hardware optimizations
Certain hardware capabilities, such as the Intel SSE instructions,
are normally detected at run time. Enable them with configure options
such as one of
--enable-arm-neon=yes
--enable-mips-msa=yes
--enable-intel-sse=yes
--enable-powerpc-vsx=yes
or enable them all at once with
--enable-hardware-optimizations=yes
or, if you are not using "configure", you can use one
or more of
CPPFLAGS += "-DPNG_ARM_NEON"
CPPFLAGS += "-DPNG_MIPS_MSA"
CPPFLAGS += "-DPNG_INTEL_SSE"
CPPFLAGS += "-DPNG_POWERPC_VSX"
See for example scripts/makefile.linux-opt
If you wish to avoid using them,
you can disable them via the configure option
--disable-hardware-optimizations
to disable them all, or
--enable-intel-sse=no
to disable a particular one,
or via compiler-command options such as
CPPFLAGS += "-DPNG_ARM_NEON_OPT=0, -DPNG_MIPS_MSA_OPT=0,
-DPNG_INTEL_SSE_OPT=0, -DPNG_POWERPC_VSX_OPT=0"
If you are using cmake, hardware optimizations are "on"
by default. To disable them, use
cmake . -DPNG_ARM_NEON=no -DPNG_INTEL_SSE=no \
-DPNG_MIPS_MSA=no -DPNG_POWERPC_VSX=no
or disable them all at once with
cmake . -DPNG_HARDWARE_OPTIMIZATIONS=no
XIII. Changes to the build and configuration of libpng in libpng-1.5.x
Details of internal changes to the library code can be found in the CHANGES
file and in the GIT repository logs. These will be of no concern to the vast
majority of library users or builders; however, the few who configure libpng
to a non-default feature set may need to change how this is done.
There should be no need for library builders to alter build scripts if
these use the distributed build support - configure or the makefiles -
however, users of the makefiles may care to update their build scripts
to build pnglibconf.h where the corresponding makefile does not do so.
Building libpng with a non-default configuration has changed completely.
The old method using pngusr.h should still work correctly even though the
way pngusr.h is used in the build has been changed; however, library
builders will probably want to examine the changes to take advantage of
new capabilities and to simplify their build system.
A. Specific changes to library configuration capabilities
The exact mechanism used to control attributes of API functions has
changed. A single set of operating system independent macro definitions
is used and operating system specific directives are defined in
pnglibconf.h
As part of this the mechanism used to choose procedure call standards on
those systems that allow a choice has been changed. At present this only
affects certain Microsoft (DOS, Windows) and IBM (OS/2) operating systems
running on Intel processors. As before, PNGAPI is defined where required
to control the exported API functions; however, two new macros, PNGCBAPI
and PNGCAPI, are used instead for callback functions (PNGCBAPI) and
(PNGCAPI) for functions that must match a C library prototype (currently
only png_longjmp_ptr, which must match the C longjmp function.) The new
approach is documented in pngconf.h
Despite these changes, libpng 1.5.0 only supports the native C function
calling standard on those platforms tested so far ("__cdecl" on Microsoft
Windows). This is because the support requirements for alternative
calling conventions seem to no longer exist. Developers who find it
necessary to set PNG_API_RULE to 1 should advise the mailing list
(png-mng-implement) of this and library builders who use Openwatcom and
therefore set PNG_API_RULE to 2 should also contact the mailing list.
B. Changes to the configuration mechanism
Prior to libpng-1.5.0 library builders who needed to configure libpng
had either to modify the exported pngconf.h header file to add system
specific configuration or had to write feature selection macros into
pngusr.h and cause this to be included into pngconf.h by defining
PNG_USER_CONFIG. The latter mechanism had the disadvantage that an
application built without PNG_USER_CONFIG defined would see the
unmodified, default, libpng API and thus would probably fail to link.
These mechanisms still work in the configure build and in any makefile
build that builds pnglibconf.h, although the feature selection macros
have changed somewhat as described above. In 1.5.0, however, pngusr.h is
processed only once, at the time the exported header file pnglibconf.h is
built. pngconf.h no longer includes pngusr.h; therefore, pngusr.h is ignored
after the build of pnglibconf.h and it is never included in an application
build.
The formerly used alternative of adding a list of feature macros to the
CPPFLAGS setting in the build also still works; however, the macros will be
copied to pnglibconf.h and this may produce macro redefinition warnings
when the individual C files are compiled.
All configuration now only works if pnglibconf.h is built from
scripts/pnglibconf.dfa. This requires the program awk. Brian Kernighan
(the original author of awk) maintains C source code of that awk and this
and all known later implementations (often called by subtly different
names - nawk and gawk for example) are adequate to build pnglibconf.h.
The Sun Microsystems (now Oracle) program 'awk' is an earlier version
and does not work; this may also apply to other systems that have a
functioning awk called 'nawk'.
Configuration options are now documented in scripts/pnglibconf.dfa. This
file also includes dependency information that ensures a configuration is
consistent; that is, if a feature is switched off, dependent features are
also switched off. As a recommended alternative to using feature macros in
pngusr.h a system builder may also define equivalent options in pngusr.dfa
(or, indeed, any file) and add that to the configuration by setting
DFA_XTRA to the file name. The makefiles in contrib/pngminim illustrate
how to do this, and also illustrate a case where pngusr.h is still required.
After you have built libpng, the definitions that were recorded in
pnglibconf.h are available to your application (pnglibconf.h is included
in png.h and gets installed alongside png.h and pngconf.h in your
$PREFIX/include directory). Do not edit pnglibconf.h after you have built
libpng, because than the settings would not accurately reflect the settings
that were used to build libpng.
XIV. Setjmp/longjmp issues
Libpng uses setjmp()/longjmp() for error handling. Unfortunately setjmp()
is known to be not thread-safe on some platforms and we don't know of
any platform where it is guaranteed to be thread-safe. Therefore, if
your application is going to be using multiple threads, you should
configure libpng with PNG_NO_SETJMP in your pngusr.dfa file, with
-DPNG_NO_SETJMP on your compile line, or with
#undef PNG_SETJMP_SUPPORTED
in your pnglibconf.h or pngusr.h.
Starting with libpng-1.6.0, the library included a "simplified API".
This requires setjmp/longjmp, so you must either build the library
with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.
XV. Common linking failures
If your application fails to find libpng or zlib entries while linking:
Be sure "-lz" appears after "-lpng" on your linking command.
Be sure you have built libpng, zlib, and your application for the
same platform (e.g., 32-bit or 64-bit).
If you are using the vstudio project, observe the WARNING in
project/vstudio/README.txt.
XVI. Other sources of information about libpng:
Further information can be found in the README and libpng-manual.txt
files, in the individual makefiles, in png.h, and the manual pages
libpng.3 and png.5.
Copyright (c) 2022 Cosmin Truta
Copyright (c) 1998-2002,2006-2016 Glenn Randers-Pehrson
This document is released under the libpng license.
For conditions of distribution and use, see the disclaimer
and license in png.h.
====================File: LICENSE====================
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE
=========================================
This modified version of libpng code adds animated PNG support and is
released under the libpng license described below. The modifications are
Copyright (c) 2006-2007 Andrew Smith, Copyright (c) 2008-2023 Max Stepin,
and are delimited by "#ifdef PNG_APNG_SUPPORTED / #endif" directives
surrounding them in the modified libpng source files.
PNG Reference Library License version 2
---------------------------------------
* Copyright (c) 1995-2023 The PNG Reference Library Authors.
* Copyright (c) 2018-2023 Cosmin Truta.
* Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
* Copyright (c) 1996-1997 Andreas Dilger.
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
The software is supplied "as is", without warranty of any kind,
express or implied, including, without limitation, the warranties
of merchantability, fitness for a particular purpose, title, and
non-infringement. In no event shall the Copyright owners, or
anyone distributing the software, be liable for any damages or
other liability, whether in contract, tort or otherwise, arising
from, out of, or in connection with the software, or the use or
other dealings in the software, even if advised of the possibility
of such damage.
Permission is hereby granted to use, copy, modify, and distribute
this software, or portions hereof, for any purpose, without fee,
subject to the following restrictions:
1. The origin of this software must not be misrepresented; you
must not claim that you wrote the original software. If you
use this software in a product, an acknowledgment in the product
documentation would be appreciated, but is not required.
2. Altered source versions must be plainly marked as such, and must
not be misrepresented as being the original software.
3. This Copyright notice may not be removed or altered from any
source or altered source distribution.
PNG Reference Library License version 1 (for libpng 0.5 through 1.6.35)
-----------------------------------------------------------------------
libpng versions 1.0.7, July 1, 2000, through 1.6.35, July 15, 2018 are
Copyright (c) 2000-2002, 2004, 2006-2018 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.
====================File: TRADEMARK====================
TRADEMARK
=========
The name "libpng" has not been registered by the Copyright owners
as a trademark in any jurisdiction. However, because libpng has
been distributed and maintained world-wide, continually since 1995,
the Copyright owners claim "common-law trademark protection" in any
jurisdiction where common-law trademark is recognized.
====================Libpng====================
INSTALL => Instructions to install libpng
LICENSE => License to use and redistribute libpng
====================Libpng====================
necessarily under the libpng license, and that some makefiles have
====================Libpng====================
the libpng license.
====================Libpng====================
Added a reference to the libpng license in each file.
====================Libpng====================
Fixed a typo in the libpng license v2.
====================Libpng====================
Refer to the libpng license instead of the libpng license in each file.
====================Libpng====================
* Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
====================Libpng====================
* Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
* libpng-0.96, and are distributed according to the same disclaimer and
====================Libpng====================
* 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
====================Libpng====================
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
* and license in png.h
====================Libpng====================
* This code is released under the libpng license. (See LICENSE, below.)
====================Libpng====================
* derived from libpng-1.0.6, and are distributed according to the same
====================Libpng====================
* 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.
====================Libpng====================
* 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.
====================Libpng====================
* released under the libpng license described below. The modifications are
====================Libpng====================
/* This code is released under the libpng license. */
/* For conditions of distribution and use, see the disclaimer */
/* and license in png.h */
====================Libpng====================
Copyright (c) 1996-1997 Andreas Dilger, are derived from libpng-0.88,
====================Libpng====================
Copyright (c) 1998-2000 Glenn Randers-Pehrson, are derived from
libpng-0.96, and are distributed according to the same disclaimer and
====================Libpng====================
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
====================Libpng====================
TRADEMARK
=========
The name "libpng" has not been registered by the Copyright owners
as a trademark in any jurisdiction. However, because libpng has
been distributed and maintained world-wide, continually since 1995,
the Copyright owners claim "common-law trademark protection" in any
jurisdiction where common-law trademark is recognized.
====================Libpng====================
This document is released under the libpng license.
For conditions of distribution and use, see the disclaimer
and license in png.h.
====================Libpng====================
derived from libpng-1.0.6, and are distributed according to the same
====================Libpng====================
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
====================Libpng====================
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.
====================Libpng====================
other copyright owners, but are released under the libpng license.
====================Libpng====================
released under the libpng license described below. The modifications are
====================libpng-2.0====================
* * Copyright (c) 1995-2023 The PNG Reference Library Authors.
* * Copyright (c) 2018-2023 Cosmin Truta.
* * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
* * Copyright (c) 1996-1997 Andreas Dilger.
* * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
*
* The software is supplied "as is", without warranty of any kind,
* express or implied, including, without limitation, the warranties
* of merchantability, fitness for a particular purpose, title, and
* non-infringement. In no event shall the Copyright owners, or
* anyone distributing the software, be liable for any damages or
* other liability, whether in contract, tort or otherwise, arising
* from, out of, or in connection with the software, or the use or
* other dealings in the software, even if advised of the possibility
* of such damage.
*
* Permission is hereby granted to use, copy, modify, and distribute
* this software, or portions hereof, for any purpose, without fee,
* subject to the following restrictions:
*
* 1. The origin of this software must not be misrepresented; you
* must not claim that you wrote the original software. If you
* use this software in a product, an acknowledgment in the product
* documentation would be appreciated, but is not required.
*
* 2. Altered source versions must be plainly marked as such, and must
* not be misrepresented as being the original software.
*
* 3. This Copyright notice may not be removed or altered from any
* source or altered source distribution.
====================libpng-2.0====================
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE
=========================================
This modified version of libpng code adds animated PNG support and is
released under the libpng license described below. The modifications are
Copyright (c) 2006-2007 Andrew Smith, Copyright (c) 2008-2023 Max Stepin,
and are delimited by "#ifdef PNG_APNG_SUPPORTED / #endif" directives
surrounding them in the modified libpng source files.
PNG Reference Library License version 2
---------------------------------------
* Copyright (c) 1995-2023 The PNG Reference Library Authors.
* Copyright (c) 2018-2023 Cosmin Truta.
* Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
* Copyright (c) 1996-1997 Andreas Dilger.
* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
The software is supplied "as is", without warranty of any kind,
express or implied, including, without limitation, the warranties
of merchantability, fitness for a particular purpose, title, and
non-infringement. In no event shall the Copyright owners, or
anyone distributing the software, be liable for any damages or
other liability, whether in contract, tort or otherwise, arising
from, out of, or in connection with the software, or the use or
other dealings in the software, even if advised of the possibility
of such damage.
Permission is hereby granted to use, copy, modify, and distribute
this software, or portions hereof, for any purpose, without fee,
subject to the following restrictions:
1. The origin of this software must not be misrepresented; you
must not claim that you wrote the original software. If you
use this software in a product, an acknowledgment in the product
documentation would be appreciated, but is not required.
2. Altered source versions must be plainly marked as such, and must
not be misrepresented as being the original software.
3. This Copyright notice may not be removed or altered from any
source or altered source distribution.
|