Pioneer BDP-V6000 Owner's Manual - Page 62

libpng, libjpg - specs

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09 62 En libpng COPYRIGHT NOTICE, DISCLAIMER, and LICENSE: If you modify libpng you may insert additional notices immediately following this sentence. libpng versions 1.2.6, August 15, 2004, through 1.2.26, April 2, 2008, are Copyright © 2004, 2006-2008 Glenn RandersPehrson, and are distributed according to the same disclaimer and license as libpng-1.2.5 with the following individual added to the list of Contributing Authors Cosmin Truta libpng versions 1.0.7, July 1, 2000, through 1.2.5 - October 3, 2002, are Copyright © 2000-2002 Glenn RandersPehrson, 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 Gilles Vollant 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 versions 0.97, January 1998, through 1.0.6, March 20, 2000, are Copyright © 1998, 1999 Glenn RandersPehrson, 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 © 1996, 1997 Andreas Dilger Distributed according to the same disclaimer and license as libpng0.88, with the following individuals added to the list of Contributing Authors: John Bowler Kevin Bracey Sam Bushell Magnus Holmgren Greg Roelofs Tom Tanner libpng versions 0.5, May 1995, through 0.88, January 1996, are Copyright © 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. A "png_get_copyright" function is available, for convenient use in "about" boxes and the like: printf("%s",png_get_copyright(NULL));Also, the PNG logo (in PNG format, of course) is supplied in the files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31). Libpng is OSI Certified Open Source Software. OSI Certified Open Source is a certification mark of the Open Source Initiative. Glenn Randers-Pehrson glennrp at users.sourceforge.net 2-Apr-08 libjpg 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 [email protected] 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 © 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

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09
62
En
libpng
COPYRIGHT NOTICE, DISCLAIMER, and LICENSE:
If you modify lib
p
ng you may inse
r
t additional notices
immediately following this sentence.
lib
p
ng ve
r
sions 1.2.6, August 15, 2004, th
r
ough 1.2.26, A
pr
il
2, 2008, a
r
e Co
p
y
r
ight © 2004, 2006-2008 Glenn Rande
r
s-
Peh
r
son, and a
r
e dist
r
ibuted acco
r
ding to the same
disclaime
r
and license as lib
p
ng-1.2.5 with the following
individual added to the list of Cont
r
ibuting Autho
r
s
Cosmin T
r
uta
lib
p
ng ve
r
sions 1.0.7, July 1, 2000, th
r
ough 1.2.5 - Octobe
r
3, 2002, a
r
e Co
p
y
r
ight © 2000-2002 Glenn Rande
r
s-
Peh
r
son, and a
r
e dist
r
ibuted acco
r
ding to the same
disclaime
r
and license as lib
p
ng-1.0.6 with the following
individuals added to the list of Cont
r
ibuting Autho
r
s
Simon-Pie
rr
e Cadieux
E
r
ic S. Raymond
Gilles Vollant
and with the following additions to the disclaime
r
:
The
r
e is no wa
rr
anty against inte
r
fe
r
ence with you
r
enjoyment of the lib
r
a
r
y o
r
against inf
r
ingement. The
r
e is
no wa
rr
anty that ou
r
effo
r
ts o
r
the lib
r
a
r
y will fulfill any of
you
r
p
a
r
ticula
r
p
u
rp
oses o
r
needs. This lib
r
a
r
y is
pr
ovided
with all faults, and the enti
r
e
r
isk of satisfacto
r
y quality,
p
e
r
fo
r
mance, accu
r
acy, and effo
r
t is with the use
r
.
lib
p
ng ve
r
sions 0.97, Janua
r
y 1998, th
r
ough 1.0.6, Ma
r
ch
20, 2000, a
r
e Co
p
y
r
ight © 1998, 1999 Glenn Rande
r
s-
Peh
r
son, and a
r
e dist
r
ibuted acco
r
ding to the same
disclaime
r
and license as lib
p
ng-0.96, with the following
individuals added to the list of Cont
r
ibuting Autho
r
s:
Tom Lane
Glenn Rande
r
s-Peh
r
son
Willem van Schaik
lib
p
ng ve
r
sions 0.89, June 1996, th
r
ough 0.96, May 1997,
a
r
e Co
p
y
r
ight © 1996, 1997 And
r
eas Dilge
r
Dist
r
ibuted
acco
r
ding to the same disclaime
r
and license as lib
p
ng-
0.88, with the following individuals added to the list of
Cont
r
ibuting Autho
r
s:
John Bowle
r
Kevin B
r
acey
Sam Bushell
Magnus Holmg
r
en
G
r
eg Roelofs
Tom Tanne
r
lib
p
ng ve
r
sions 0.5, May 1995, th
r
ough 0.88, Janua
r
y 1996,
a
r
e Co
p
y
r
ight © 1995, 1996 Guy E
r
ic Schalnat, G
r
ou
p
42,
Inc.
Fo
r
the
p
u
rp
oses of this co
p
y
r
ight and license,
“Cont
r
ibuting Autho
r
s” is defined as the following set of
individuals:
And
r
eas Dilge
r
Dave Ma
r
tindale
Guy E
r
ic Schalnat
Paul Schmidt
Tim Wegne
r
The PNG Refe
r
ence Lib
r
a
r
y is su
pp
lied “AS IS”. The
Cont
r
ibuting Autho
r
s and G
r
ou
p
42, Inc. disclaim all
wa
rr
anties, ex
pr
essed o
r
im
p
lied, including, without
limitation, the wa
rr
anties of me
r
chantability and of fitness
fo
r
any
p
u
rp
ose. The Cont
r
ibuting Autho
r
s and G
r
ou
p
42,
Inc. assume no liability fo
r
di
r
ect, indi
r
ect, incidental,
s
p
ecial, exem
p
la
r
y, o
r
consequential damages, which may
r
esult f
r
om the use of the PNG Refe
r
ence Lib
r
a
r
y, even if
advised of the
p
ossibility of such damage.
Pe
r
mission is he
r
eby g
r
anted to use, co
p
y, modify, and
dist
r
ibute this sou
r
ce code, o
r
p
o
r
tions he
r
eof, fo
r
any
p
u
rp
ose, without fee, subject to the following
r
est
r
ictions:
1.
The o
r
igin of this sou
r
ce code must not be mis
r
e
pr
esented.
2. Alte
r
ed ve
r
sions must be
p
lainly ma
r
ked as such and
must not be mis
r
e
pr
esented as being the o
r
iginal sou
r
ce.
3.
This Co
p
y
r
ight notice may not be
r
emoved o
r
alte
r
ed f
r
om
any sou
r
ce o
r
alte
r
ed sou
r
ce dist
r
ibution.
The Cont
r
ibuting Autho
r
s and G
r
ou
p
42, Inc. s
p
ecifically
p
e
r
mit, without fee, and encou
r
age the use of this sou
r
ce
code as a com
p
onent to su
pp
o
r
ting the PNG file fo
r
mat in
comme
r
cial
pr
oducts. If you use this sou
r
ce code in a
pr
oduct, acknowledgment is not
r
equi
r
ed but would be
a
ppr
eciated.
A “
p
ng_get_co
p
y
r
ight” function is available, fo
r
convenient
use in “about” boxes and the like:
pr
intf(“%s”,
p
ng_get_co
p
y
r
ight(NULL));Also, the PNG logo
(in PNG fo
r
mat, of cou
r
se) is su
pp
lied in the files
p
ngba
r
.
p
ng” and “
p
ngba
r
.j
p
g (88x31) and “
p
ngnow.
p
ng”
(98x31).
Lib
p
ng is OSI Ce
r
tified O
p
en Sou
r
ce Softwa
r
e. OSI Ce
r
tified
O
p
en Sou
r
ce is a ce
r
tification ma
r
k of the O
p
en Sou
r
ce
Initiative.
Glenn Rande
r
s-Peh
r
son
glenn
rp
at use
r
s.sou
r
cefo
r
ge.net
2-A
pr
-08
libjpg
The Inde
p
endent JPEG G
r
ou
p
’s JPEG softwa
r
e
README fo
r
r
elease 6b of 27-Ma
r
-1998
This dist
r
ibution contains the sixth
p
ublic
r
elease of the
Inde
p
endent JPEG G
r
ou
p
’s f
r
ee JPEG softwa
r
e. You a
r
e
welcome to
r
edist
r
ibute this softwa
r
e and to use it fo
r
any
p
u
rp
ose, subject to the conditions unde
r
LEGAL ISSUES,
below.
Se
r
ious use
r
s of this softwa
r
e (
p
a
r
ticula
r
ly those
inco
rp
o
r
ating it into la
r
ge
r
pr
og
r
ams) should contact IJG at
j
p
[email protected] to be added to ou
r
elect
r
onic
mailing list. Mailing list membe
r
s a
r
e notified of u
p
dates
and have a chance to
p
a
r
tici
p
ate in technical discussions,
etc.
This softwa
r
e is the wo
r
k of Tom Lane, Phili
p
Gladstone, Jim
Bouche
r
, Lee C
r
ocke
r
, Julian Minguillon, Luis O
r
tiz, Geo
r
ge
Philli
p
s, Davide Rossi, Guido Vollbeding, Ge’ Weije
r
s, and
othe
r
membe
r
s of the Inde
p
endent JPEG G
r
ou
p
.
IJG is not affiliated with the official ISO JPEG standa
r
ds
committee.
DOCUMENTATION ROADMAP
This file contains the following sections:
OVERVIEW
Gene
r
al desc
r
i
p
tion of JPEG and
the IJG softwa
r
e.
LEGAL ISSUES
Co
p
y
r
ight, lack of wa
rr
anty, te
r
ms
of dist
r
ibution.
REFERENCES
Whe
r
e to lea
r
n mo
r
e about JPEG.
ARCHIVE LOCATIONS
Whe
r
e to find newe
r
ve
r
sions of
this softwa
r
e.
RELATED SOFTWARE
Othe
r
stuff you should get.
FILE FORMAT WARS
Softwa
r
e *not* to get.
TO DO
Plans fo
r
futu
r
e IJG
r
eleases.
Othe
r
documentation files in the dist
r
ibution a
r
e:
Use
r
documentation:
install.doc
How to configu
r
e and install the IJG
softwa
r
e.
usage.doc
Usage inst
r
uctions fo
r
cj
p
eg, dj
p
eg,
j
p
egt
r
an,
r
dj
p
gcom, and w
r
j
p
gcom.
*.1 Unix-style man
p
ages fo
r
pr
og
r
ams (same info as
usage.doc).
wiza
r
d.doc
Advanced usage inst
r
uctions fo
r
JPEG
wiza
r
ds only.
change.log
Ve
r
sion-to-ve
r
sion change highlights.
P
r
og
r
amme
r
and inte
r
nal documentation:
libj
p
eg.doc
How to use the JPEG lib
r
a
r
y in you
r
own
pr
og
r
ams.
exam
p
le.c
Sam
p
le code fo
r
calling the JPEG lib
r
a
r
y.
st
r
uctu
r
e.doc
Ove
r
view of the JPEG lib
r
a
r
y’s inte
r
nal
st
r
uctu
r
e.
filelist.doc
Road ma
p
of IJG files.
code
r
ules.doc
Coding style
r
ules ---
p
lease
r
ead if you
cont
r
ibute code.
Please
r
ead at least the files install.doc and usage.doc.
Useful info
r
mation can also be found in the JPEG FAQ
(F
r
equently Asked Questions) a
r
ticle. See ARCHIVE
LOCATIONS below to find out whe
r
e to obtain the FAQ
a
r
ticle.
If you want to unde
r
stand how the JPEG code wo
r
ks, we
suggest
r
eading one o
r
mo
r
e of the REFERENCES, then
looking at the documentation files (in
r
oughly the o
r
de
r
listed) befo
r
e diving into the code.
OVERVIEW
This
p
ackage contains C softwa
r
e to im
p
lement JPEG
image com
pr
ession and decom
pr
ession. JPEG
(
pr
onounced “jay-
p
eg”) is a standa
r
dized com
pr
ession
method fo
r
full-colo
r
and g
r
ay-scale images. JPEG is
intended fo
r
com
pr
essing
r
eal-wo
r
ld scenes; line d
r
awings,
ca
r
toons and othe
r
non-
r
ealistic images a
r
e not its st
r
ong
suit. JPEG is lossy, meaning that the out
p
ut image is not
exactly identical to the in
p
ut image. Hence you must not
use JPEG if you have to have identical out
p
ut bits. Howeve
r
,
on ty
p
ical
p
hotog
r
a
p
hic images, ve
r
y good com
pr
ession
levels can be obtained with no visible change, and
r
ema
r
kably high com
pr
ession levels a
r
e
p
ossible if you can
tole
r
ate a low-quality image. Fo
r
mo
r
e details, see the
r
efe
r
ences, o
r
just ex
p
e
r
iment with va
r
ious com
pr
ession
settings.
This softwa
r
e im
p
lements JPEG baseline, extended-
sequential, and
pr
og
r
essive com
pr
ession
pr
ocesses.
P
r
ovision is made fo
r
su
pp
o
r
ting all va
r
iants of these
pr
ocesses, although some uncommon
p
a
r
amete
r
settings
a
r
en’t im
p
lemented yet. Fo
r
legal
r
easons, we a
r
e not
dist
r
ibuting code fo
r
the a
r
ithmetic-coding va
r
iants of
JPEG; see LEGAL ISSUES. We have made no
pr
ovision fo
r
su
pp
o
r
ting the hie
r
a
r
chical o
r
lossless
pr
ocesses defined
in the standa
r
d.
We
pr
ovide a set of lib
r
a
r
y
r
outines fo
r
r
eading and w
r
iting
JPEG image files,
p
lus two sam
p
le a
pp
lications “cj
p
eg” and
“dj
p
eg”, which use the lib
r
a
r
y to
p
e
r
fo
r
m conve
r
sion
between JPEG and some othe
r
p
o
p
ula
r
image file fo
r
mats.
The lib
r
a
r
y is intended to be
r
eused in othe
r
a
pp
lications.
In o
r
de
r
to su
pp
o
r
t file conve
r
sion and viewing softwa
r
e, we
have included conside
r
able functionality beyond the ba
r
e
JPEG coding/decoding ca
p
ability; fo
r
exam
p
le, the colo
r
quantization modules a
r
e not st
r
ictly
p
a
r
t of JPEG
decoding, but they a
r
e essential fo
r
out
p
ut to colo
r
ma
pp
ed
file fo
r
mats o
r
colo
r
ma
pp
ed dis
p
lays. These ext
r
a functions
can be com
p
iled out of the lib
r
a
r
y if not
r
equi
r
ed fo
r
a
p
a
r
ticula
r
a
pp
lication. We have also included j
p
egt
r
an, a
utility fo
r
lossless t
r
anscoding between diffe
r
ent JPEG
pr
ocesses, and “
r
dj
p
gcom” and “w
r
j
p
gcom”, two sim
p
le
a
pp
lications fo
r
inse
r
ting and ext
r
acting textual comments
in JFIF files.
The em
p
hasis in designing this softwa
r
e has been on
achieving
p
o
r
tability and flexibility, while also making it fast
enough to be useful. In
p
a
r
ticula
r
, the softwa
r
e is not
intended to be
r
ead as a tuto
r
ial on JPEG. (See the
REFERENCES section fo
r
int
r
oducto
r
y mate
r
ial.) Rathe
r
, it
is intended to be
r
eliable,
p
o
r
table, indust
r
ial-st
r
ength
code. We do not claim to have achieved that goal in eve
r
y
as
p
ect of the softwa
r
e, but we st
r
ive fo
r
it.
We welcome the use of this softwa
r
e as a com
p
onent of
comme
r
cial
pr
oducts. No
r
oyalty is
r
equi
r
ed, but we do ask
fo
r
an acknowledgement in
pr
oduct documentation, as
desc
r
ibed unde
r
LEGAL ISSUES.
LEGAL ISSUES
In
p
lain English:
1. We don’t
pr
omise that this softwa
r
e wo
r
ks. (But if you
find any bugs,
p
lease let us know!)
2. You can use this softwa
r
e fo
r
whateve
r
you want. You
don’t have to
p
ay us.
3. You may not
pr
etend that you w
r
ote this softwa
r
e. If you
use it in a
pr
og
r
am, you must acknowledge somewhe
r
e
in you
r
documentation that you’ve used the IJG code.
In legalese:
The autho
r
s make NO WARRANTY o
r
r
e
pr
esentation, eithe
r
ex
pr
ess o
r
im
p
lied, with
r
es
p
ect to this softwa
r
e, its quality,
accu
r
acy, me
r
chantability, o
r
fitness fo
r
a
p
a
r
ticula
r
p
u
rp
ose. This softwa
r
e is
pr
ovided “AS IS”, and you, its
use
r
, assume the enti
r
e
r
isk as to its quality and accu
r
acy.
This softwa
r
e is co
p
y
r
ight © 1991-1998, Thomas G. Lane. All
Rights Rese
r
ved exce
p
t as s
p
ecified below.
Pe
r
mission is he
r
eby g
r
anted to use, co
p
y, modify, and
dist
r
ibute this softwa
r
e (o
r
p
o
r
tions the
r
eof) fo
r
any
p
u
rp
ose, without fee, subject to these conditions:
(1)If any
p
a
r
t of the sou
r
ce code fo
r
this softwa
r
e is
dist
r
ibuted, then this README file must be included,
with this co
p
y
r
ight and no-wa
rr
anty notice unalte
r
ed;
and any additions, deletions, o
r
changes to the o
r
iginal
files must be clea
r
ly indicated in accom
p
anying
documentation.
(2)If only executable code is dist
r
ibuted, then the
accom
p
anying documentation must state that “this
softwa
r
e is based in
p
a
r
t on the wo
r
k of the Inde
p
endent
JPEG G
r
ou
p
”.
(3)Pe
r
mission fo
r
use of this softwa
r
e is g
r
anted only if the
use
r
acce
p
ts full
r
es
p
onsibility fo
r
any undesi
r
able
consequences; the autho
r
s acce
p
t NO LIABILITY fo
r
damages of any kind.
These conditions a
pp
ly to any softwa
r
e de
r
ived f
r
om o
r
based on the IJG code, not just to the unmodified lib
r
a
r
y. If
you use ou
r
wo
r
k, you ought to acknowledge us.
Pe
r
mission is NOT g
r
anted fo
r
the use of any IJG autho
r
’s
name o
r
com
p
any name in adve
r
tising o
r
p
ublicity
r
elating
to this softwa
r
e o
r
pr
oducts de
r
ived f
r
om it. This softwa
r
e
may be
r
efe
rr
ed to only as “the Inde
p
endent JPEG G
r
ou
p
’s
softwa
r
e”.
We s
p
ecifically
p
e
r
mit and encou
r
age the use of this
softwa
r
e as the basis of comme
r
cial
pr
oducts,
pr
ovided
that all wa
rr
anty o
r
liability claims a
r
e assumed by the
pr
oduct vendo
r
.
ansi2kn
r
.c is included in this dist
r
ibution by
p
e
r
mission of
L. Pete
r
Deutsch, sole
pr
o
pr
ieto
r
of its co
p
y
r
ight holde
r
,
Aladdin Ente
rpr
ises of Menlo Pa
r
k, CA. ansi2kn
r
.c is NOT
cove
r
ed by the above co
p
y
r
ight and conditions, but instead
by the usual dist
r
ibution te
r
ms of the F
r
ee Softwa
r
e
Foundation;
pr
inci
p
ally, that you must include sou
r
ce code
if you
r
edist
r
ibute it. (See the file ansi2kn
r
.c fo
r
full details.)
Howeve
r
, since ansi2kn
r
.c is not needed as
p
a
r
t of any
pr
og
r
am gene
r
ated f
r
om the IJG code, this does not limit
you mo
r
e than the fo
r
egoing
p
a
r
ag
r
a
p
hs do.
The Unix configu
r
ation sc
r
i
p
t “configu
r
e” was
pr
oduced
with GNU Autoconf. It is co
p
y
r
ight by the F
r
ee Softwa
r
e
Foundation but is f
r
eely dist
r
ibutable. The same holds fo
r
its
su
pp
o
r
ting sc
r
i
p
ts (config.guess, config.sub, ltconfig,
ltmain.sh). Anothe
r
su
pp
o
r
t sc
r
i
p
t, install-sh, is co
p
y
r
ight
by M.I.T. but is also f
r
eely dist
r
ibutable.
It a
pp
ea
r
s that the a
r
ithmetic coding o
p
tion of the JPEG
s
p
ec is cove
r
ed by
p
atents owned by IBM, AT&T, and
Mitsubishi. Hence a
r
ithmetic coding cannot legally be
used without obtaining one o
r
mo
r
e licenses. Fo
r
this
r
eason, su
pp
o
r
t fo
r
a
r
ithmetic coding has been
r
emoved
f
r
om the f
r
ee JPEG softwa
r
e. (Since a
r
ithmetic coding
pr
ovides only a ma
r
ginal gain ove
r
the un
p
atented Huffman
mode, it is unlikely that ve
r
y many im
p
lementations will
su
pp
o
r
t it.) So fa
r
as we a
r
e awa
r
e, the
r
e a
r
e no
p
atent
r
est
r
ictions on the
r
emaining code.
The IJG dist
r
ibution fo
r
me
r
ly included code to
r
ead and
w
r
ite GIF files. To avoid entanglement with the Unisys LZW
p
atent, GIF
r
eading su
pp
o
r
t has been
r
emoved altogethe
r
,
and the GIF w
r
ite
r
has been sim
p
lified to
pr
oduce
uncom
pr
essed GIFs. This technique does not use the LZW
algo
r
ithm; the
r
esulting GIF files a
r
e la
r
ge
r
than usual, but
a
r
e
r
eadable by all standa
r
d GIF decode
r
s.
We a
r
e
r
equi
r
ed to state that