djpeg.c


Log

Author Commit Date CI Message
DRC 7c1a1789 2020-11-05T16:04:55 Merge branch 'master' into dev
DRC 6e632af9 2020-11-04T10:13:06 Demote "fast" [I]DCT algorithms to legacy status - Refer to the "slow" [I]DCT algorithms as "accurate" instead, since they are not slow under libjpeg-turbo. - Adjust documentation claims to reflect the fact that the "slow" and "fast" algorithms produce about the same performance on AVX2-equipped CPUs (because of the dual-lane nature of AVX2, it was not possible to accelerate the "fast" algorithm beyond what was achievable with SSE2.) Also adjust the claims to reflect the fact that the "fast" algorithm tends to be ~5-15% faster than the "slow" algorithm on non-AVX2-equipped CPUs, regardless of the use of the libjpeg-turbo SIMD extensions. - Indicate the legacy status of the "fast" and float algorithms in the documentation and cjpeg/djpeg usage info. - Remove obsolete paragraph in the djpeg man page that suggested that the float algorithm could be faster than the "fast" algorithm on some CPUs.
DRC 88ae6098 2020-10-27T13:28:56 Merge branch 'ijg' into dev - Restore GIF read/compressed GIF write support from jpeg-6a and jpeg-9d. - Integrate jpegtran -wipe and -drop options from jpeg-9a and jpeg-9d. - Integrate jpegtran -crop extension (for expanding the image size) from jpeg-9a and jpeg-9d. - Integrate other minor code tweaks from jpeg-9*
Guido Vollbeding 9fc018fd 2020-01-12T00:00:00 The Independent JPEG Group's JPEG software v9d
DRC fe79f56b 2020-07-28T15:09:00 Merge branch 'master' into dev
DRC c1037f43 2020-07-28T14:57:47 Fix bad return val when skipping past end of image Fixes #439
DRC 167b5a80 2020-01-08T15:02:58 Merge branch 'master' into dev
DRC f81833ae 2020-01-08T15:01:38 Remove more unnecessary NULL checks before free()
DRC c4675d62 2019-12-31T00:42:53 Merge branch 'master' into dev
DRC fe50cd99 2019-12-30T23:52:34 djpeg.c: Fix compiler warning w/o mem. src manager insize is only used when the in-memory source manager is compiled in.
DRC 80acd5c4 2019-12-19T10:20:52 Remove code for the obsolete RLE image format libjpeg-turbo never included that code, because it requires an external library (the Utah Raster Toolkit.) The RLE image format was supplanted by GIF in the late 1980s, so it is rarely seen these days. (It had a lousy Weissman score, anyhow.)
DRC e98b0612 2019-12-18T15:12:33 Add fault tolerance features to djpeg and jpegtran - Enable progress reporting at run time using a new -report argument (cjpeg now supports that argument as well) - Limit the allowable number of scans using a new -maxscans argument - Treat warnings as fatal using a new -strict argument This mainly demonstrates how to work around the two issues with the JPEG standard described here: https://libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf since those and similar issues continue to be erroneously reported as libjpeg-turbo bugs.
DRC 52fef349 2019-12-10T19:10:55 Eliminate internal use of GETJOCTET() macro Because of 01e30323546d37792e4f682d78d58bb8b3e185ab (officially eliminating support for compilers without unsigned char, since we never effectively supported those compilers anyhow), GETJOCTET() is now a no-op. Since that macro is in jmorecfg.h, it is part of the de facto libjpeg API and must remain in the public headers. However, there is no reason to continue using it internally, and eliminating its internal use improves code readability.
DRC 19c791cd 2018-03-08T10:55:20 Improve code formatting consistency With rare exceptions ... - Always separate line continuation characters by one space from preceding code. - Always use two-space indentation. Never use tabs. - Always use K&R-style conditional blocks. - Always surround operators with spaces, except in raw assembly code. - Always put a space after, but not before, a comma. - Never put a space between type casts and variables/function calls. - Never put a space between the function name and the argument list in function declarations and prototypes. - Always surround braces ('{' and '}') with spaces. - Always surround statements (if, for, else, catch, while, do, switch) with spaces. - Always attach pointer symbols ('*' and '**') to the variable or function name. - Always precede pointer symbols ('*' and '**') by a space in type casts. - Use the MIN() macro from jpegint.h within the libjpeg and TurboJPEG API libraries (using min() from tjutil.h is still necessary for TJBench.) - Where it makes sense (particularly in the TurboJPEG code), put a blank line after variable declaration blocks. - Always separate statements in one-liners by two spaces. The purpose of this was to ease maintenance on my part and also to make it easier for contributors to figure out how to format patch submissions. This was admittedly confusing (even to me sometimes) when we had 3 or 4 different style conventions in the same source tree. The new convention is more consistent with the formatting of other OSS code bases. This commit corrects deviations from the chosen formatting style in the libjpeg API code and reformats the TurboJPEG API code such that it conforms to the same standard. NOTES: - Although it is no longer necessary for the function name in function declarations to begin in Column 1 (this was historically necessary because of the ansi2knr utility, which allowed libjpeg to be built with non-ANSI compilers), we retain that formatting for the libjpeg code because it improves readability when using libjpeg's function attribute macros (GLOBAL(), etc.) - This reformatting project was accomplished with the help of AStyle and Uncrustify, although neither was completely up to the task, and thus a great deal of manual tweaking was required. Note to developers of code formatting utilities: the libjpeg-turbo code base is an excellent test bed, because AFAICT, it breaks every single one of the utilities that are currently available. - The legacy (MMX, SSE, 3DNow!) assembly code for i386 has been formatted to match the SSE2 code (refer to ff5685d5344273df321eb63a005eaae19d2496e3.) I hadn't intended to bother with this, but the Loongson MMI implementation demonstrated that there is still academic value to the MMX implementation, as an algorithmic model for other 64-bit vector implementations. Thus, it is desirable to improve its readability in the same manner as that of the SSE2 implementation.
DRC aa745905 2017-11-16T18:09:07 TurboJPEG C API: Add BMP/PPM load/save functions The main justification for this is to provide new libjpeg-turbo users with a quick & easy way of developing a complete JPEG compression/decompression program without requiring them to build libjpeg-turbo from source (which was necessary in order to use the project-private bmp API) or to use external libraries. These new functions build upon significant enhancements to rdbmp.c, wrbmp.c, rdppm.c, and wrppm.c which allow those engines to convert directly between the native pixel format of the file and a pixel format ("colorspace" in libjpeg parlance) specified by the calling program. rdbmp.c and wrbmp.c have also been modified such that the calling program can choose to read or write image rows in the native (bottom-up) order of the file format, thus eliminating the need to use an inversion array. tjLoadImage() and tjSaveImage() leverage these new underlying features in order to significantly improve upon the performance of the old bmp API. Because these new functions cannot work without the libjpeg-turbo colorspace extensions, the libjpeg-compatible code in turbojpeg.c has been removed. That code was only there to serve as an example of how to use the TurboJPEG API on top of libjpeg, but more specific, buildable examples now exist in the https://github.com/libjpeg-turbo/ijg repository.
DRC 4893e5d8 2017-11-17T19:00:53 Merge branch 'master' into dev
DRC 5bc43c78 2017-11-13T21:01:53 Further partial image decompression fixes - Referring to 073b0e88a192adebbb479ee2456beb089d8b5de7 and #185, the reason why BMP and RLE didn't (and won't) work with partial image decompression is that the output engines for both formats maintain a whole-image buffer, which is used to reverse the order of scanlines. However, it was straightforward to add -crop support for GIF and Targa, which is useful for testing partial image decompression along with color quantization. - Such testing reproduced a bug reported by Mozilla (refer to PR #182) whereby jpeg_skip_scanlines() would segfault if color quantization was enabled. To fix this issue, read_and_discard_scanlines() now sets up a dummy quantize function in the same manner that it sets up a dummy color conversion function. Closes #182
DRC 073b0e88 2017-11-08T21:01:57 djpeg -crop: Exit gracefully with non-PPM formats ... and document that only PPM/PGM output images are supported with the -crop option for the moment. I investigated the possibility of supporting -crop with -bmp, but even after resetting the buffer dimensions, I still kept getting virtual array access errors. It seems that doing this the "right way" would require creating a re-initialization function for each image format's destination manager. I'm disinclined to do that right now, given that this feature was Google's baby (developed as a prerequisite for including libjpeg-turbo in Android), and the -crop option in djpeg is intended only as an example of how to use the partial image decompression API. Real-world applications would need to handle this in their own destination managers. It would probably be possible to make this work with Targa by employing a similar hack to the one we used with PPM, but Targa isn't popular enough to bother. Fixes #185
DRC 44b2399a 2017-01-19T15:18:57 libjpeg API: Support reading/writing ICC profiles This commit does the following: -- Merges the two glueware functions (read_icc_profile() and write_icc_profile()) from iccjpeg.c, which is contained in downstream projects such as LCMS, Ghostscript, Mozilla, etc. These functions were originally intended for inclusion in libjpeg, but Tom Lane left the IJG before that could be accomplished. Since then, programs and libraries that needed to embed/extract ICC profiles in JPEG files had to include their own local copy of iccjpeg.c, which is suboptimal. -- The new functions were prefixed with jpeg_ and split into separate files for the compressor and decompressor, per the existing libjpeg coding standards. -- jpeg_write_icc_profile() was made slightly more fault-tolerant. It will now trigger a libjpeg error if it is called before jpeg_start_compress() or if it is passed NULL arguments. -- jpeg_read_icc_profile() was made slightly more fault-tolerant. It will now trigger a libjpeg error if it is called before jpeg_read_header() or if it is passed NULL arguments. It will also now trigger libjpeg warnings if the ICC profile data is corrupt. -- The code comments have been wordsmithed. -- Note that the one-line setup_read_icc_profile() function was not included. Instead, libjpeg.txt now documents the need to call jpeg_save_markers(cinfo, JPEG_APP0 + 2, 0xFFFF) prior to calling jpeg_read_header(), if jpeg_read_icc_profile() is to be used. -- Adds documentation for the new functions to libjpeg.txt. -- Adds an -icc switch to cjpeg and jpegtran that allows those programs to embed an ICC profile in the JPEG files they generate. -- Adds an -icc switch to djpeg that allows that program to extract an ICC profile from a JPEG file while decompressing. -- Adds appropriate unit tests for all of the above. -- Bumps the SO_AGE of the libjpeg API library to indicate the presence of new API functions. Note that the licensing information was obtained from: https://github.com/mm2/Little-CMS/issues/37#issuecomment-66450180
DRC 3ab68cf5 2016-02-19T18:32:10 libjpeg API: Partial scanline decompression This, in combination with the existing jpeg_skip_scanlines() function, provides the ability to crop the image both horizontally and vertically while decompressing (certain restrictions apply-- see libjpeg.txt.) This also cleans up the documentation of the line skipping feature and removes the "strip decompression" feature from djpeg, since the new cropping feature is a superset of it. Refer to #34 for discussion. Closes #34
DRC e621dfc5 2016-02-19T10:35:09 More minor code formatting tweaks
DRC bd49803f 2016-02-19T08:53:33 Use consistent/modern code formatting for pointers The convention used by libjpeg: type * variable; is not very common anymore, because it looks too much like multiplication. Some (particularly C++ programmers) prefer to tuck the pointer symbol against the type: type* variable; to emphasize that a pointer to a type is effectively a new type. However, this can also be confusing, since defining multiple variables on the same line would not work properly: type* variable1, variable2; /* Only variable1 is actually a pointer. */ This commit reformats the entirety of the libjpeg-turbo code base so that it uses the same code formatting convention for pointers that the TurboJPEG API code uses: type *variable1, *variable2; This seems to be the most common convention among C programmers, and it is the convention used by other codec libraries, such as libpng and libtiff.
DRC 54e6b8e8 2016-02-18T15:16:17 Include some comments/doc tweaks from jpeg-9+
Guido Vollbeding a560e4b4 2016-01-17T00:00:00 The Independent JPEG Group's JPEG software v9b
Guido Vollbeding e7f88aec 2013-01-13T00:00:00 The Independent JPEG Group's JPEG software v9
DRC 1e32fe31 2015-10-14T17:32:39 Replace INT32 with a new internal datatype (JLONG) These days, INT32 is a commonly-defined datatype in system headers. We cannot eliminate the definition of that datatype from jmorecfg.h, since the INT32 typedef has technically been part of the libjpeg API since version 5 (1994.) However, using INT32 internally is risky, because the inclusion of a particular header (Xmd.h, for instance) could change the definition of INT32 from long to int on 64-bit platforms and thus change the internal behavior of libjpeg-turbo in unexpected ways (for instance, failing to correctly set __INT32_IS_ACTUALLY_LONG to match the INT32 typedef-- perhaps as a result of including the wrong version of jpeglib.h-- could cause libjpeg-turbo to produce incorrect results.) The library has always been built in environments in which INT32 is effectively long (on Windows, long is always 32-bit, so effectively it's the same as int), so it makes sense to turn INT32 into an explicitly long datatype. This ensures that libjpeg-turbo will always behave consistently, regardless of the headers included at compile time. Addresses a concern expressed in #26.
DRC 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.
MIYASAKA Masaru a2e6a9dd 2006-02-04T00:00:00 IJG R6b with x86SIMD V1.02 Independent JPEG Group's JPEG software release 6b with x86 SIMD extension for IJG JPEG library version 1.02
Thomas G. Lane 489583f5 1996-02-07T00:00:00 The Independent JPEG Group's JPEG software v6a
Thomas G. Lane bc79e068 1995-08-02T00:00:00 The Independent JPEG Group's JPEG software v6
Thomas G. Lane 9ba2f5ed 1994-12-07T00:00:00 The Independent JPEG Group's JPEG software v5a
Thomas G. Lane 36a4cccc 1994-09-24T00:00:00 The Independent JPEG Group's JPEG software v5
Guido Vollbeding 5996a25e 2009-06-27T00:00:00 The Independent JPEG Group's JPEG software v7
Thomas G. Lane 5ead57a3 1998-03-27T00:00:00 The Independent JPEG Group's JPEG software v6b
DRC 7a7da946 2015-06-27T08:10:31 Add regression tests for jpeg_skip_scanlines(); change "stripe" to "strip" in djpeg; document -strip and -skip parameters in djpeg git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1587 632fc199-4ca6-4c93-a231-07263d6284db
DRC 07afe8a5 2015-06-25T03:44:37 Add a -skip option to djpeg, which opens up further regression testing options. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1583 632fc199-4ca6-4c93-a231-07263d6284db
DRC eb32cc1e 2015-06-25T03:44:36 Add a new libjpeg API function (jpeg_skip_scanlines()) to allow for partially decoding a JPEG image. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1582 632fc199-4ca6-4c93-a231-07263d6284db
DRC 306add8b 2014-11-22T04:25:04 Fix whitespace issues introduced with previous commit. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.4.x@1423 632fc199-4ca6-4c93-a231-07263d6284db
DRC 9665f5e3 2014-11-22T04:04:38 Print the library version and exit whenever -version is passed to cjpeg, djpeg, or jpegtran. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.4.x@1422 632fc199-4ca6-4c93-a231-07263d6284db
DRC 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
DRC 78df2e61 2014-05-12T09:23:57 Add support for decompressing to RGB565 (16-bit) pixels git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1295 632fc199-4ca6-4c93-a231-07263d6284db
DRC 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
DRC 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
DRC ff6961f3 2014-04-20T09:17:11 This patch accomplishes the following: -- Auto-generates HAVE_LOCALE_H macro and adds it to jconfig.h (this is used by rdjpgcom.c.) -- Reconciles the description and ordering of macros between config.h.in and jconfig.h.in, so the two files can be easily diffed. -- Eliminates the use of the autoheader-generated config.h in the project and moves relevant internal-only macros into a new file, jconfigint.h. This is to avoid "already defined" warnings in files that were including both config.h (to get the internal autotools package information or the INLINE definition) and jconfig.h. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1258 632fc199-4ca6-4c93-a231-07263d6284db
DRC c45653e4 2013-10-12T21:52:48 Fix a couple of issues with return value checking. JFREAD(), which wraps fread(), will never return -1. fread() will instead return 0 or a short object count if an error occurs, and ferror() will return 1 in that case. The second issue was that we were assigning the return value of ftell() to an unsigned long prior to checking the value, so the value would never be < 0 if an error occurred. It would instead be (unsigned long)-1. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1061 632fc199-4ca6-4c93-a231-07263d6284db
DRC a6ef282a 2013-09-28T03:23:49 Some of the IJG headers say "Modified by", so clarify that our "Modifications" are not referring to these. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1053 632fc199-4ca6-4c93-a231-07263d6284db
DRC 6cd1ec4b 2013-03-23T05:35:37 It's more correct to say "The Independent JPEG Group's software", since libjpeg-turbo emulates both the command-line and application programming interfaces. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@932 632fc199-4ca6-4c93-a231-07263d6284db
DRC 736fb062 2013-01-18T23:45:06 Compiler warnings on Windows git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@914 632fc199-4ca6-4c93-a231-07263d6284db
DRC ab70623e 2013-01-18T23:42:31 Implement in-memory source/destination managers even when not emulating the libjpeg v8 API/ABI git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@913 632fc199-4ca6-4c93-a231-07263d6284db
DRC 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
DRC c3ba39fc 2012-02-07T23:05:46 Merge copyright messages into one string and change the run-time messages to avoid confusion (we are not technically based on the latest libjpeg, although we do borrow some code from it) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.1.x@781 632fc199-4ca6-4c93-a231-07263d6284db
DRC 1d5b1cf3 2012-01-31T10:39:29 Merge copyright messages into one string and change the run-time messages to avoid confusion (we are not technically based on the latest libjpeg, although we do borrow some code from it) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@766 632fc199-4ca6-4c93-a231-07263d6284db
DRC 6a833a8e 2011-03-03T16:58:47 Add an option to force grayscale->RGB conversion (needed for jpgtest regression test) git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@493 632fc199-4ca6-4c93-a231-07263d6284db
DRC 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
DRC 2cdd2ae7 2010-10-10T06:54:21 Display libjpeg-turbo version/copyrights in run-time programs git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@247 632fc199-4ca6-4c93-a231-07263d6284db
Constantin Kaplinsky c8753072 2006-05-25T05:01:55 Migrating to new directory structure adopted from the RealVNC's source tree. More changes will follow. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1 632fc199-4ca6-4c93-a231-07263d6284db