Issue #1933 - Part 1: Update build system for libjpeg-turbo.

This commit is contained in:
Job Bautista 2022-06-24 22:33:06 +08:00 • committed by roytam1
commit 75e223e3bf
8 changed files with 350 additions and 348 deletions

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@ -43,7 +43,7 @@ User documentation:
change.log Version-to-version change highlights.
Programmer and internal documentation:
libjpeg.txt How to use the JPEG library in your own programs.
example.c Sample code for calling the JPEG library.
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.
@ -128,7 +128,7 @@ 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.
This software is copyright (C) 1991-2020, Thomas G. Lane, Guido Vollbeding.
All Rights Reserved except as specified below.
Permission is hereby granted to use, copy, modify, and distribute this
@ -159,25 +159,6 @@ commercial products, provided that all warranty or liability claims are
assumed by the product vendor.
The Unix configuration script "configure" was produced with GNU Autoconf.
It is copyright by the Free Software Foundation but is freely distributable.
The same holds for its supporting scripts (config.guess, config.sub,
ltmain.sh). Another support script, install-sh, is copyright by X Consortium
but is also freely distributable.
The IJG distribution formerly included code to read and write GIF files.
To avoid entanglement with the Unisys LZW patent (now expired), GIF reading
support has been removed altogether, and the GIF writer has been simplified
to produce "uncompressed GIFs". This technique does not use the LZW
algorithm; the resulting GIF files are larger than usual, but are readable
by all standard GIF decoders.
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
==========
@ -185,8 +166,8 @@ 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.
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
@ -220,21 +201,21 @@ 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 1.02 has been adopted as an Ecma International Technical Report
and thus received a formal publication status. It is available as a free
download in PDF format from
http://www.ecma-international.org/publications/techreports/E-TR-098.htm.
A PostScript version of the JFIF document is available at
http://www.ijg.org/files/jfif.ps.gz. There is also a plain text version at
http://www.ijg.org/files/jfif.txt.gz, but it is missing the figures.
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
The TIFF 6.0 file format specification can be obtained from
http://mirrors.ctan.org/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
@ -249,28 +230,26 @@ 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 mail-server@rtfm.mit.edu
with body
send usenet/news.answers/jpeg-faq/part1
send usenet/news.answers/jpeg-faq/part2
general information about JPEG. It is available at
http://www.faqs.org/faqs/jpeg-faq.
FILE FORMAT WARS
================
FILE FORMAT COMPATIBILITY
=========================
The ISO/IEC JTC1/SC29/WG1 standards committee (also known as JPEG, together
with ITU-T SG16) currently promotes different formats containing the name
"JPEG" which are incompatible with original DCT-based JPEG. IJG therefore does
not support these formats (see REFERENCES). Indeed, one of the original
reasons for developing this free software was to help force convergence on
common, interoperable format standards for JPEG files.
Don't use an incompatible file format!
(In any case, our decoder will remain capable of reading existing JPEG
image files indefinitely.)
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