kmx git

Commit	Date	Message
bf9f319c	2023-06-29T16:07:42	Disallow color quantization with lossless decomp Color quantization is a legacy feature that serves little or no purpose with lossless JPEG images. 9f756bc67a84d4566bf74a0c2432aa55da404021 eliminated interaction issues between the lossless decompressor and the color quantizers related to out-of-range 12-bit samples, but referring to #701, other interaction issues apparently still exist. Such issues are likely, given the fact that the color quantizers were not designed with lossless decompression in mind. This commit reverts 9f756bc67a84d4566bf74a0c2432aa55da404021, since the issues it fixed are no longer relevant because of this commit and 2192560d74e6e6cf99dd05928885573be00a8208. Fixed #672 Fixes #673 Fixes #674 Fixes #676 Fixes #677 Fixes #678 Fixes #679 Fixes #681 Fixes #683 Fixes #701
2241434e	2022-12-15T12:20:50	16-bit lossless JPEG support
97772cba	2022-11-14T15:36:25	Merge branch 'ijg.lossless' into dev Refer to #402
e8b40f3c	2022-11-01T21:45:39	Vastly improve 12-bit JPEG integration The Gordian knot that 7fec5074f962b20ed00b4f5da4533e1e8d4ed8ac attempted to unravel was caused by the fact that there are several data-precision-dependent (JSAMPLE-dependent) fields and methods in the exposed libjpeg API structures, and if you change the exposed libjpeg API structures, then you have to change the whole API. If you change the whole API, then you have to provide a whole new library to support the new API, and that makes it difficult to support multiple data precisions in the same application. (It is not impossible, as example.c demonstrated, but using data-precision-dependent libjpeg API structures would have made the cjpeg, djpeg, and jpegtran source code hard to read, so it made more sense to build, install, and package 12-bit-specific versions of those applications.) Unfortunately, the result of that initial integration effort was an unreadable and unmaintainable mess, which is a problem for a library that is an ISO/ITU-T reference implementation. Also, as I dug into the problem of lossless JPEG support, I realized that 16-bit lossless JPEG images are a thing, and supporting yet another version of the libjpeg API just for those images is untenable. In fact, however, the touch points for JSAMPLE in the exposed libjpeg API structures are minimal: - The colormap and sample_range_limit fields in jpeg_decompress_struct - The alloc_sarray() and access_virt_sarray() methods in jpeg_memory_mgr - jpeg_write_scanlines() and jpeg_write_raw_data() - jpeg_read_scanlines() and jpeg_read_raw_data() - jpeg_skip_scanlines() and jpeg_crop_scanline() (This is subtle, but both of those functions use JSAMPLE-dependent opaque structures behind the scenes.) It is much more readable and maintainable to provide 12-bit-specific versions of those six top-level API functions and to document that the aforementioned methods and fields must be type-cast when using 12-bit samples. Since that eliminates the need to provide a 12-bit-specific version of the exposed libjpeg API structures, we can: - Compile only the precision-dependent libjpeg modules (the coefficient buffer controllers, the colorspace converters, the DCT/IDCT managers, the main buffer controllers, the preprocessing and postprocessing controller, the downsampler and upsamplers, the quantizers, the integer DCT methods, and the IDCT methods) for multiple data precisions. - Introduce 12-bit-specific methods into the various internal structures defined in jpegint.h. - Create precision-independent data type, macro, method, field, and function names that are prefixed by an underscore, and use an internal header to convert those into precision-dependent data type, macro, method, field, and function names, based on the value of BITS_IN_JSAMPLE, when compiling the precision-dependent libjpeg modules. - Expose precision-dependent jinit() functions for each of the precision-dependent libjpeg modules. - Abstract the precision-dependent libjpeg modules by calling the appropriate precision-dependent jinit() function, based on the value of cinfo->data_precision, from top-level libjpeg API functions.
7fec5074	2022-03-08T12:34:11	Support 8-bit & 12-bit JPEGs using the same build Partially implements #199 This commit also implements a request from #178 (the ability to compile the libjpeg example as a standalone program.)
01e30323	2019-01-23T14:58:24	Eliminate support for compilers w/o unsigned char libjpeg-turbo has never really supported such compilers, since (AFAIK) they are non-existent on any modern computing platform and thus impossible for us to test. (Also, the TurboJPEG API would break without unsigned chars.) Furthermore, the unified CMake-based build system introduced in 2.0 always defines HAVE_UNSIGNED_CHAR, so retaining other code paths is pointless. Eliminating support for compilers without unsigned char eliminates the need for the GETJSAMPLE() macro, which improves the readability of many parts of the code as well as improving the performance of writing Targa and Windows BMP files. Fixes #317
a6289526	2018-07-24T18:36:51	Fix JPEG spec references per ISO/ITU-T suggestions - When referring to specific clauses, annexes, tables, and figures, a "timed reference" (a reference that includes the year) must be used in order to avoid confusion. - "CCITT" = "ITU-T" - Replace ambiguous "JPEG spec" with the specific document number.
da2a27ef	2017-03-18T16:15:14	Honor max_memory_to_use/JPEGMEM/-maxmemory This re-introduces a feature of the obsolete system-specific libjpeg memory managers-- namely the ability to limit the amount of main memory used by the library during decompression or multi-pass compression. This is mainly beneficial for two reasons: - Works around a 2 GB limit in libFuzzer - Allows security-sensitive applications to set a memory limit for the JPEG decoder so as to work around the progressive JPEG exploit (LJT-01-004) described here: http://www.libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf This commit also removes obsolete documentation regarding the MS-DOS memory manager (which itself was removed long ago) and changes the documentation of the -maxmemory switch and JPEGMEM environment variable to reflect the fact that backing stores are never used in libjpeg-turbo. Inspired by: https://github.com/caolanm/libjpeg-turbo/commit/066fee2e7d6834f24838bc1896aa38ca77209e3c Closes #143
fc11193e	2014-01-19T00:00:00	The Independent JPEG Group's JPEG software v9a
7e3acc0e	2015-10-10T10:25:46	Rename README, LICENSE, BUILDING text files The IJG README file has been renamed to README.ijg, in order to avoid confusion (many people were assuming that that was our project's README file and weren't reading README-turbo.txt) and to lay the groundwork for markdown versions of the libjpeg-turbo README and build instructions.
5829cb23	2012-01-15T00:00:00	The Independent JPEG Group's JPEG software v8d
5996a25e	2009-06-27T00:00:00	The Independent JPEG Group's JPEG software v7
5033f3e1	2014-05-18T18:33:44	Remove MS-DOS code and information, and adjust copyright headers to reflect the removal of features in r1307 and r1308. libjpeg-turbo has never supported MS-DOS, nor is it even possible for us to do so. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1312 632fc199-4ca6-4c93-a231-07263d6284db
da13af6b	2014-05-18T17:52:06	Further copyright header cleanup git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1310 632fc199-4ca6-4c93-a231-07263d6284db
d88f7ddf	2014-05-18T17:51:00	Further copyright header cleanup git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1309 632fc199-4ca6-4c93-a231-07263d6284db
b7753510	2014-05-11T09:36:25	Convert tabs to spaces in the libjpeg code and the SIMD code (TurboJPEG retains the use of tabs for historical reasons. They were annoying in the libjpeg code primarily because they were not consistently used and because they were used to format as well as indent the code. In the case of TurboJPEG, tabs are used just to indent the code, so even if the editor assumes a different tab width, the code will still be readable.) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1285 632fc199-4ca6-4c93-a231-07263d6284db
e5eaf374	2014-05-09T18:00:32	Convert tabs to spaces in the libjpeg code and the SIMD code (TurboJPEG retains the use of tabs for historical reasons. They were annoying in the libjpeg code primarily because they were not consistently used and because they were used to format as well as indent the code. In the case of TurboJPEG, tabs are used just to indent the code, so even if the editor assumes a different tab width, the code will still be readable.) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1278 632fc199-4ca6-4c93-a231-07263d6284db
a73e870a	2012-12-31T02:52:30	Change the copyright notices to make it clear that our modified files are not part of the IJG's software. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@873 632fc199-4ca6-4c93-a231-07263d6284db
0bfb7805	2012-12-31T02:42:18	Change the copyright notices to make it clear that our modified files are not part of the IJG's software. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@872 632fc199-4ca6-4c93-a231-07263d6284db
760ea8df	2012-02-07T23:25:19	Merge documentation and wordsmithing changes from 1.2, including promotion of -arithmetic to a "switch for advanced users" git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.1.x@783 632fc199-4ca6-4c93-a231-07263d6284db
66a69f04	2012-01-31T10:19:29	Incorporate a few upstream doc changes; grammar police; wordsmithing; Move -arithmetic into "switches for advanced users"; Additional documentation for IDCT scaling extensions git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@765 632fc199-4ca6-4c93-a231-07263d6284db
ccd1bfdd	2012-01-31T09:53:46	Incorporate a few upstream doc changes; grammar police; wordsmithing; Move -arithmetic into "switches for advanced users" git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@764 632fc199-4ca6-4c93-a231-07263d6284db
66f97e68	2010-11-23T05:49:54	Support arithmetic encoding and decoding git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@299 632fc199-4ca6-4c93-a231-07263d6284db
39ea562c	2010-10-12T01:55:31	Document new v7/v8 features; .doc = .txt git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@252 632fc199-4ca6-4c93-a231-07263d6284db

bf9f319c

2023-06-29T16:07:42

Disallow color quantization with lossless decomp Color quantization is a legacy feature that serves little or no purpose with lossless JPEG images. 9f756bc67a84d4566bf74a0c2432aa55da404021 eliminated interaction issues between the lossless decompressor and the color quantizers related to out-of-range 12-bit samples, but referring to #701, other interaction issues apparently still exist. Such issues are likely, given the fact that the color quantizers were not designed with lossless decompression in mind. This commit reverts 9f756bc67a84d4566bf74a0c2432aa55da404021, since the issues it fixed are no longer relevant because of this commit and 2192560d74e6e6cf99dd05928885573be00a8208. Fixed #672 Fixes #673 Fixes #674 Fixes #676 Fixes #677 Fixes #678 Fixes #679 Fixes #681 Fixes #683 Fixes #701

2241434e

2022-12-15T12:20:50

16-bit lossless JPEG support

97772cba

2022-11-14T15:36:25

Merge branch 'ijg.lossless' into dev Refer to #402

e8b40f3c

2022-11-01T21:45:39

Vastly improve 12-bit JPEG integration The Gordian knot that 7fec5074f962b20ed00b4f5da4533e1e8d4ed8ac attempted to unravel was caused by the fact that there are several data-precision-dependent (JSAMPLE-dependent) fields and methods in the exposed libjpeg API structures, and if you change the exposed libjpeg API structures, then you have to change the whole API. If you change the whole API, then you have to provide a whole new library to support the new API, and that makes it difficult to support multiple data precisions in the same application. (It is not impossible, as example.c demonstrated, but using data-precision-dependent libjpeg API structures would have made the cjpeg, djpeg, and jpegtran source code hard to read, so it made more sense to build, install, and package 12-bit-specific versions of those applications.) Unfortunately, the result of that initial integration effort was an unreadable and unmaintainable mess, which is a problem for a library that is an ISO/ITU-T reference implementation. Also, as I dug into the problem of lossless JPEG support, I realized that 16-bit lossless JPEG images are a thing, and supporting yet another version of the libjpeg API just for those images is untenable. In fact, however, the touch points for JSAMPLE in the exposed libjpeg API structures are minimal: - The colormap and sample_range_limit fields in jpeg_decompress_struct - The alloc_sarray() and access_virt_sarray() methods in jpeg_memory_mgr - jpeg_write_scanlines() and jpeg_write_raw_data() - jpeg_read_scanlines() and jpeg_read_raw_data() - jpeg_skip_scanlines() and jpeg_crop_scanline() (This is subtle, but both of those functions use JSAMPLE-dependent opaque structures behind the scenes.) It is much more readable and maintainable to provide 12-bit-specific versions of those six top-level API functions and to document that the aforementioned methods and fields must be type-cast when using 12-bit samples. Since that eliminates the need to provide a 12-bit-specific version of the exposed libjpeg API structures, we can: - Compile only the precision-dependent libjpeg modules (the coefficient buffer controllers, the colorspace converters, the DCT/IDCT managers, the main buffer controllers, the preprocessing and postprocessing controller, the downsampler and upsamplers, the quantizers, the integer DCT methods, and the IDCT methods) for multiple data precisions. - Introduce 12-bit-specific methods into the various internal structures defined in jpegint.h. - Create precision-independent data type, macro, method, field, and function names that are prefixed by an underscore, and use an internal header to convert those into precision-dependent data type, macro, method, field, and function names, based on the value of BITS_IN_JSAMPLE, when compiling the precision-dependent libjpeg modules. - Expose precision-dependent jinit*() functions for each of the precision-dependent libjpeg modules. - Abstract the precision-dependent libjpeg modules by calling the appropriate precision-dependent jinit*() function, based on the value of cinfo->data_precision, from top-level libjpeg API functions.

7fec5074

2022-03-08T12:34:11

Support 8-bit & 12-bit JPEGs using the same build Partially implements #199 This commit also implements a request from #178 (the ability to compile the libjpeg example as a standalone program.)

01e30323

2019-01-23T14:58:24

Eliminate support for compilers w/o unsigned char libjpeg-turbo has never really supported such compilers, since (AFAIK) they are non-existent on any modern computing platform and thus impossible for us to test. (Also, the TurboJPEG API would break without unsigned chars.) Furthermore, the unified CMake-based build system introduced in 2.0 always defines HAVE_UNSIGNED_CHAR, so retaining other code paths is pointless. Eliminating support for compilers without unsigned char eliminates the need for the GETJSAMPLE() macro, which improves the readability of many parts of the code as well as improving the performance of writing Targa and Windows BMP files. Fixes #317

a6289526

2018-07-24T18:36:51

Fix JPEG spec references per ISO/ITU-T suggestions - When referring to specific clauses, annexes, tables, and figures, a "timed reference" (a reference that includes the year) must be used in order to avoid confusion. - "CCITT" = "ITU-T" - Replace ambiguous "JPEG spec" with the specific document number.

da2a27ef

2017-03-18T16:15:14

Honor max_memory_to_use/JPEGMEM/-maxmemory This re-introduces a feature of the obsolete system-specific libjpeg memory managers-- namely the ability to limit the amount of main memory used by the library during decompression or multi-pass compression. This is mainly beneficial for two reasons: - Works around a 2 GB limit in libFuzzer - Allows security-sensitive applications to set a memory limit for the JPEG decoder so as to work around the progressive JPEG exploit (LJT-01-004) described here: http://www.libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf This commit also removes obsolete documentation regarding the MS-DOS memory manager (which itself was removed long ago) and changes the documentation of the -maxmemory switch and JPEGMEM environment variable to reflect the fact that backing stores are never used in libjpeg-turbo. Inspired by: https://github.com/caolanm/libjpeg-turbo/commit/066fee2e7d6834f24838bc1896aa38ca77209e3c Closes #143

fc11193e

2014-01-19T00:00:00

The Independent JPEG Group's JPEG software v9a

7e3acc0e

2015-10-10T10:25:46

Rename README, LICENSE, BUILDING text files The IJG README file has been renamed to README.ijg, in order to avoid confusion (many people were assuming that that was our project's README file and weren't reading README-turbo.txt) and to lay the groundwork for markdown versions of the libjpeg-turbo README and build instructions.

5829cb23

2012-01-15T00:00:00

The Independent JPEG Group's JPEG software v8d

5996a25e

2009-06-27T00:00:00

The Independent JPEG Group's JPEG software v7

5033f3e1

2014-05-18T18:33:44

Remove MS-DOS code and information, and adjust copyright headers to reflect the removal of features in r1307 and r1308. libjpeg-turbo has never supported MS-DOS, nor is it even possible for us to do so. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1312 632fc199-4ca6-4c93-a231-07263d6284db

da13af6b

2014-05-18T17:52:06

Further copyright header cleanup git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1310 632fc199-4ca6-4c93-a231-07263d6284db

d88f7ddf

2014-05-18T17:51:00

Further copyright header cleanup git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1309 632fc199-4ca6-4c93-a231-07263d6284db

b7753510

2014-05-11T09:36:25

Convert tabs to spaces in the libjpeg code and the SIMD code (TurboJPEG retains the use of tabs for historical reasons. They were annoying in the libjpeg code primarily because they were not consistently used and because they were used to format as well as indent the code. In the case of TurboJPEG, tabs are used just to indent the code, so even if the editor assumes a different tab width, the code will still be readable.) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1285 632fc199-4ca6-4c93-a231-07263d6284db

e5eaf374

2014-05-09T18:00:32

Convert tabs to spaces in the libjpeg code and the SIMD code (TurboJPEG retains the use of tabs for historical reasons. They were annoying in the libjpeg code primarily because they were not consistently used and because they were used to format as well as indent the code. In the case of TurboJPEG, tabs are used just to indent the code, so even if the editor assumes a different tab width, the code will still be readable.) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1278 632fc199-4ca6-4c93-a231-07263d6284db

a73e870a

2012-12-31T02:52:30

Change the copyright notices to make it clear that our modified files are not part of the IJG's software. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@873 632fc199-4ca6-4c93-a231-07263d6284db

0bfb7805

2012-12-31T02:42:18

Change the copyright notices to make it clear that our modified files are not part of the IJG's software. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@872 632fc199-4ca6-4c93-a231-07263d6284db

760ea8df

2012-02-07T23:25:19

Merge documentation and wordsmithing changes from 1.2, including promotion of -arithmetic to a "switch for advanced users" git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.1.x@783 632fc199-4ca6-4c93-a231-07263d6284db

66a69f04

2012-01-31T10:19:29

Incorporate a few upstream doc changes; grammar police; wordsmithing; Move -arithmetic into "switches for advanced users"; Additional documentation for IDCT scaling extensions git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@765 632fc199-4ca6-4c93-a231-07263d6284db

ccd1bfdd

2012-01-31T09:53:46

Incorporate a few upstream doc changes; grammar police; wordsmithing; Move -arithmetic into "switches for advanced users" git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@764 632fc199-4ca6-4c93-a231-07263d6284db

66f97e68

2010-11-23T05:49:54

Support arithmetic encoding and decoding git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@299 632fc199-4ca6-4c93-a231-07263d6284db

39ea562c

2010-10-12T01:55:31

Document new v7/v8 features; .doc = .txt git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@252 632fc199-4ca6-4c93-a231-07263d6284db

kc3-lang/libjpeg-turbo/structure.txt

structure.txt

Log