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diff --git a/src/3rdparty/libjpeg/src/README.ijg b/src/3rdparty/libjpeg/src/README.ijg index 2e39f965c2..8f3768265f 100644 --- a/src/3rdparty/libjpeg/src/README.ijg +++ b/src/3rdparty/libjpeg/src/README.ijg @@ -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.txt Sample code for calling the JPEG library. + example.c 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. @@ -68,17 +68,17 @@ 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 +JPEG is normally 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, progressive, and +lossless 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 processes defined in the standard. We provide a set of library routines for reading and writing JPEG image files, @@ -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 @@ -159,19 +159,6 @@ 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 ========== @@ -223,12 +210,12 @@ 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 @@ -243,14 +230,8 @@ 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 COMPATIBILITY @@ -260,7 +241,7 @@ 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, +are incompatible with the original 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 |