jquant1.c


Log

Author Commit Date CI Message
DRC 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
luzpaz 43c58ff9 2018-07-31T21:59:16 Correct various typos in code comments Found via `codespell -q 3` Closes #263
DRC 293263c3 2018-03-17T15:14:35 Format preprocessor macros more consistently Within the libjpeg API code, it seems to be more the convention than not to separate the macro name and value by two or more spaces, which improves general readability. Making this consistent across all of libjpeg-turbo is less about my individual preferences and more about making it easy to automatically detect variations from our chosen formatting convention. I intend to release the script I'm using to validate this stuff, once it matures and stabilizes a bit.
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 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 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.
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 a8b67c4f 1995-03-15T00:00:00 The Independent JPEG Group's JPEG software v5b
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
Thomas G. Lane cc7150e2 1993-02-18T00:00:00 The Independent JPEG Group's JPEG software v4a
Thomas G. Lane 88aeed42 1992-12-10T00:00:00 The Independent JPEG Group's JPEG software v4
Thomas G. Lane 4a6b7303 1992-03-17T00:00:00 The Independent JPEG Group's JPEG software v3
Thomas G. Lane bd543f03 1991-12-13T00:00:00 The Independent JPEG Group's JPEG software v2
Thomas G. Lane 2cbeb8ab 1991-10-07T00:00:00 The Independent JPEG Group's JPEG software v1
Guido Vollbeding 5829cb23 2012-01-15T00:00:00 The Independent JPEG Group's JPEG software v8d
DRC 5de454b2 2014-05-18T19:04:03 libjpeg-turbo has never supported non-ANSI compilers, so get rid of the crufty SIZEOF() macro. It was not being used consistently anyhow, so it would not have been possible to build prior releases of libjpeg-turbo using the broken compilers for which that macro was designed. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1313 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 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 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 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 8ece7fef 2009-08-06T08:32:00 Update copyrights to indicate files modified with colorspace extensions git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@57 632fc199-4ca6-4c93-a231-07263d6284db
DRC f25c071e 2009-04-03T12:00:51 Implement new colorspaces to allow directly compressing from/decompressing to RGB/RGBX/BGR/BGRX/XBGR/XRGB without conversion git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@35 632fc199-4ca6-4c93-a231-07263d6284db