diff options
Diffstat (limited to 'src/3rdparty/libjpeg/install.doc')
| -rw-r--r-- | src/3rdparty/libjpeg/install.doc | 1063 |
1 files changed, 0 insertions, 1063 deletions
diff --git a/src/3rdparty/libjpeg/install.doc b/src/3rdparty/libjpeg/install.doc deleted file mode 100644 index ce5d5b659..000000000 --- a/src/3rdparty/libjpeg/install.doc +++ /dev/null @@ -1,1063 +0,0 @@ -INSTALLATION INSTRUCTIONS for the Independent JPEG Group's JPEG software - -Copyright (C) 1991-1998, Thomas G. Lane. -This file is part of the Independent JPEG Group's software. -For conditions of distribution and use, see the accompanying README file. - - -This file explains how to configure and install the IJG software. We have -tried to make this software extremely portable and flexible, so that it can be -adapted to almost any environment. The downside of this decision is that the -installation process is complicated. We have provided shortcuts to simplify -the task on common systems. But in any case, you will need at least a little -familiarity with C programming and program build procedures for your system. - -If you are only using this software as part of a larger program, the larger -program's installation procedure may take care of configuring the IJG code. -For example, Ghostscript's installation script will configure the IJG code. -You don't need to read this file if you just want to compile Ghostscript. - -If you are on a Unix machine, you may not need to read this file at all. -Try doing - ./configure - make - make test -If that doesn't complain, do - make install -(better do "make -n install" first to see if the makefile will put the files -where you want them). Read further if you run into snags or want to customize -the code for your system. - - -TABLE OF CONTENTS ------------------ - -Before you start -Configuring the software: - using the automatic "configure" script - using one of the supplied jconfig and makefile files - by hand -Building the software -Testing the software -Installing the software -Optional stuff -Optimization -Hints for specific systems - - -BEFORE YOU START -================ - -Before installing the software you must unpack the distributed source code. -Since you are reading this file, you have probably already succeeded in this -task. However, there is a potential for error if you needed to convert the -files to the local standard text file format (for example, if you are on -MS-DOS you may have converted LF end-of-line to CR/LF). You must apply -such conversion to all the files EXCEPT those whose names begin with "test". -The test files contain binary data; if you change them in any way then the -self-test will give bad results. - -Please check the last section of this file to see if there are hints for the -specific machine or compiler you are using. - - -CONFIGURING THE SOFTWARE -======================== - -To configure the IJG code for your system, you need to create two files: - * jconfig.h: contains values for system-dependent #define symbols. - * Makefile: controls the compilation process. -(On a non-Unix machine, you may create "project files" or some other -substitute for a Makefile. jconfig.h is needed in any environment.) - -We provide three different ways to generate these files: - * On a Unix system, you can just run the "configure" script. - * We provide sample jconfig files and makefiles for popular machines; - if your machine matches one of the samples, just copy the right sample - files to jconfig.h and Makefile. - * If all else fails, read the instructions below and make your own files. - - -Configuring the software using the automatic "configure" script ---------------------------------------------------------------- - -If you are on a Unix machine, you can just type - ./configure -and let the configure script construct appropriate configuration files. -If you're using "csh" on an old version of System V, you might need to type - sh configure -instead to prevent csh from trying to execute configure itself. -Expect configure to run for a few minutes, particularly on slower machines; -it works by compiling a series of test programs. - -Configure was created with GNU Autoconf and it follows the usual conventions -for GNU configure scripts. It makes a few assumptions that you may want to -override. You can do this by providing optional switches to configure: - -* If you want to build libjpeg as a shared library, say - ./configure --enable-shared -To get both shared and static libraries, say - ./configure --enable-shared --enable-static -Note that these switches invoke GNU libtool to take care of system-dependent -shared library building methods. If things don't work this way, please try -running configure without either switch; that should build a static library -without using libtool. If that works, your problem is probably with libtool -not with the IJG code. libtool is fairly new and doesn't support all flavors -of Unix yet. (You might be able to find a newer version of libtool than the -one included with libjpeg; see ftp.gnu.org. Report libtool problems to -bug-libtool@gnu.org.) - -* Configure will use gcc (GNU C compiler) if it's available, otherwise cc. -To force a particular compiler to be selected, use the CC option, for example - ./configure CC='cc' -The same method can be used to include any unusual compiler switches. -For example, on HP-UX you probably want to say - ./configure CC='cc -Aa' -to get HP's compiler to run in ANSI mode. - -* The default CFLAGS setting is "-O" for non-gcc compilers, "-O2" for gcc. -You can override this by saying, for example, - ./configure CFLAGS='-g' -if you want to compile with debugging support. - -* Configure will set up the makefile so that "make install" will install files -into /usr/local/bin, /usr/local/man, etc. You can specify an installation -prefix other than "/usr/local" by giving configure the option "--prefix=PATH". - -* If you don't have a lot of swap space, you may need to enable the IJG -software's internal virtual memory mechanism. To do this, give the option -"--enable-maxmem=N" where N is the default maxmemory limit in megabytes. -This is discussed in more detail under "Selecting a memory manager", below. -You probably don't need to worry about this on reasonably-sized Unix machines, -unless you plan to process very large images. - -Configure has some other features that are useful if you are cross-compiling -or working in a network of multiple machine types; but if you need those -features, you probably already know how to use them. - - -Configuring the software using one of the supplied jconfig and makefile files ------------------------------------------------------------------------------ - -If you have one of these systems, you can just use the provided configuration -files: - -Makefile jconfig file System and/or compiler - -makefile.manx jconfig.manx Amiga, Manx Aztec C -makefile.sas jconfig.sas Amiga, SAS C -makeproj.mac jconfig.mac Apple Macintosh, Metrowerks CodeWarrior -mak*jpeg.st jconfig.st Atari ST/STE/TT, Pure C or Turbo C -makefile.bcc jconfig.bcc MS-DOS or OS/2, Borland C -makefile.dj jconfig.dj MS-DOS, DJGPP (Delorie's port of GNU C) -makefile.mc6 jconfig.mc6 MS-DOS, Microsoft C (16-bit only) -makefile.wat jconfig.wat MS-DOS, OS/2, or Windows NT, Watcom C -makefile.vc jconfig.vc Windows NT/95, MS Visual C++ -make*.ds jconfig.vc Windows NT/95, MS Developer Studio -makefile.mms jconfig.vms Digital VMS, with MMS software -makefile.vms jconfig.vms Digital VMS, without MMS software - -Copy the proper jconfig file to jconfig.h and the makefile to Makefile (or -whatever your system uses as the standard makefile name). For more info see -the appropriate system-specific hints section near the end of this file. - - -Configuring the software by hand --------------------------------- - -First, generate a jconfig.h file. If you are moderately familiar with C, -the comments in jconfig.doc should be enough information to do this; just -copy jconfig.doc to jconfig.h and edit it appropriately. Otherwise, you may -prefer to use the ckconfig.c program. You will need to compile and execute -ckconfig.c by hand --- we hope you know at least enough to do that. -ckconfig.c may not compile the first try (in fact, the whole idea is for it -to fail if anything is going to). If you get compile errors, fix them by -editing ckconfig.c according to the directions given in ckconfig.c. Once -you get it to run, it will write a suitable jconfig.h file, and will also -print out some advice about which makefile to use. - -You may also want to look at the canned jconfig files, if there is one for a -system similar to yours. - -Second, select a makefile and copy it to Makefile (or whatever your system -uses as the standard makefile name). The most generic makefiles we provide -are - makefile.ansi: if your C compiler supports function prototypes - makefile.unix: if not. -(You have function prototypes if ckconfig.c put "#define HAVE_PROTOTYPES" -in jconfig.h.) You may want to start from one of the other makefiles if -there is one for a system similar to yours. - -Look over the selected Makefile and adjust options as needed. In particular -you may want to change the CC and CFLAGS definitions. For instance, if you -are using GCC, set CC=gcc. If you had to use any compiler switches to get -ckconfig.c to work, make sure the same switches are in CFLAGS. - -If you are on a system that doesn't use makefiles, you'll need to set up -project files (or whatever you do use) to compile all the source files and -link them into executable files cjpeg, djpeg, jpegtran, rdjpgcom, and wrjpgcom. -See the file lists in any of the makefiles to find out which files go into -each program. Note that the provided makefiles all make a "library" file -libjpeg first, but you don't have to do that if you don't want to; the file -lists identify which source files are actually needed for compression, -decompression, or both. As a last resort, you can make a batch script that -just compiles everything and links it all together; makefile.vms is an example -of this (it's for VMS systems that have no make-like utility). - -Here are comments about some specific configuration decisions you'll -need to make: - -Command line style ------------------- - -These programs can use a Unix-like command line style which supports -redirection and piping, like this: - cjpeg inputfile >outputfile - cjpeg <inputfile >outputfile - source program | cjpeg >outputfile -The simpler "two file" command line style is just - cjpeg inputfile outputfile -You may prefer the two-file style, particularly if you don't have pipes. - -You MUST use two-file style on any system that doesn't cope well with binary -data fed through stdin/stdout; this is true for some MS-DOS compilers, for -example. If you're not on a Unix system, it's safest to assume you need -two-file style. (But if your compiler provides either the Posix-standard -fdopen() library routine or a Microsoft-compatible setmode() routine, you -can safely use the Unix command line style, by defining USE_FDOPEN or -USE_SETMODE respectively.) - -To use the two-file style, make jconfig.h say "#define TWO_FILE_COMMANDLINE". - -Selecting a memory manager --------------------------- - -The IJG code is capable of working on images that are too big to fit in main -memory; data is swapped out to temporary files as necessary. However, the -code to do this is rather system-dependent. We provide five different -memory managers: - -* jmemansi.c This version uses the ANSI-standard library routine tmpfile(), - which not all non-ANSI systems have. On some systems - tmpfile() may put the temporary file in a non-optimal - location; if you don't like what it does, use jmemname.c. - -* jmemname.c This version creates named temporary files. For anything - except a Unix machine, you'll need to configure the - select_file_name() routine appropriately; see the comments - near the head of jmemname.c. If you use this version, define - NEED_SIGNAL_CATCHER in jconfig.h to make sure the temp files - are removed if the program is aborted. - -* jmemnobs.c (That stands for No Backing Store :-).) This will compile on - almost any system, but it assumes you have enough main memory - or virtual memory to hold the biggest images you work with. - -* jmemdos.c This should be used with most 16-bit MS-DOS compilers. - See the system-specific notes about MS-DOS for more info. - IMPORTANT: if you use this, define USE_MSDOS_MEMMGR in - jconfig.h, and include the assembly file jmemdosa.asm in the - programs. The supplied makefiles and jconfig files for - 16-bit MS-DOS compilers already do both. - -* jmemmac.c Custom version for Apple Macintosh; see the system-specific - notes for Macintosh for more info. - -To use a particular memory manager, change the SYSDEPMEM variable in your -makefile to equal the corresponding object file name (for example, jmemansi.o -or jmemansi.obj for jmemansi.c). - -If you have plenty of (real or virtual) main memory, just use jmemnobs.c. -"Plenty" means about ten bytes for every pixel in the largest images -you plan to process, so a lot of systems don't meet this criterion. -If yours doesn't, try jmemansi.c first. If that doesn't compile, you'll have -to use jmemname.c; be sure to adjust select_file_name() for local conditions. -You may also need to change unlink() to remove() in close_backing_store(). - -Except with jmemnobs.c or jmemmac.c, you need to adjust the DEFAULT_MAX_MEM -setting to a reasonable value for your system (either by adding a #define for -DEFAULT_MAX_MEM to jconfig.h, or by adding a -D switch to the Makefile). -This value limits the amount of data space the program will attempt to -allocate. Code and static data space isn't counted, so the actual memory -needs for cjpeg or djpeg are typically 100 to 150Kb more than the max-memory -setting. Larger max-memory settings reduce the amount of I/O needed to -process a large image, but too large a value can result in "insufficient -memory" failures. On most Unix machines (and other systems with virtual -memory), just set DEFAULT_MAX_MEM to several million and forget it. At the -other end of the spectrum, for MS-DOS machines you probably can't go much -above 300K to 400K. (On MS-DOS the value refers to conventional memory only. -Extended/expanded memory is handled separately by jmemdos.c.) - - -BUILDING THE SOFTWARE -===================== - -Now you should be able to compile the software. Just say "make" (or -whatever's necessary to start the compilation). Have a cup of coffee. - -Here are some things that could go wrong: - -If your compiler complains about undefined structures, you should be able to -shut it up by putting "#define INCOMPLETE_TYPES_BROKEN" in jconfig.h. - -If you have trouble with missing system include files or inclusion of the -wrong ones, read jinclude.h. This shouldn't happen if you used configure -or ckconfig.c to set up jconfig.h. - -There are a fair number of routines that do not use all of their parameters; -some compilers will issue warnings about this, which you can ignore. There -are also a few configuration checks that may give "unreachable code" warnings. -Any other warning deserves investigation. - -If you don't have a getenv() library routine, define NO_GETENV. - -Also see the system-specific hints, below. - - -TESTING THE SOFTWARE -==================== - -As a tquick test of functionality we've included a small sample image in -several forms: - testorig.jpg Starting point for the djpeg tests. - testimg.ppm The output of djpeg testorig.jpg - testimg.bmp The output of djpeg -bmp -colors 256 testorig.jpg - testimg.jpg The output of cjpeg testimg.ppm - testprog.jpg Progressive-mode equivalent of testorig.jpg. - testimgp.jpg The output of cjpeg -progressive -optimize testimg.ppm -(The first- and second-generation .jpg files aren't identical since JPEG is -lossy.) If you can generate duplicates of the testimg* files then you -probably have working programs. - -With most of the makefiles, "make test" will perform the necessary -comparisons. - -If you're using a makefile that doesn't provide the test option, run djpeg -and cjpeg by hand and compare the output files to testimg* with whatever -binary file comparison tool you have. The files should be bit-for-bit -identical. - -If the programs complain "MAX_ALLOC_CHUNK is wrong, please fix", then you -need to reduce MAX_ALLOC_CHUNK to a value that fits in type size_t. -Try adding "#define MAX_ALLOC_CHUNK 65520L" to jconfig.h. A less likely -configuration error is "ALIGN_TYPE is wrong, please fix": defining ALIGN_TYPE -as long should take care of that one. - -If the cjpeg test run fails with "Missing Huffman code table entry", it's a -good bet that you needed to define RIGHT_SHIFT_IS_UNSIGNED. Go back to the -configuration step and run ckconfig.c. (This is a good plan for any other -test failure, too.) - -If you are using Unix (one-file) command line style on a non-Unix system, -it's a good idea to check that binary I/O through stdin/stdout actually -works. You should get the same results from "djpeg <testorig.jpg >out.ppm" -as from "djpeg -outfile out.ppm testorig.jpg". Note that the makefiles all -use the latter style and therefore do not exercise stdin/stdout! If this -check fails, try recompiling with USE_SETMODE or USE_FDOPEN defined. -If it still doesn't work, better use two-file style. - -If you chose a memory manager other than jmemnobs.c, you should test that -temporary-file usage works. Try "djpeg -bmp -colors 256 -max 0 testorig.jpg" -and make sure its output matches testimg.bmp. If you have any really large -images handy, try compressing them with -optimize and/or decompressing with --colors 256 to make sure your DEFAULT_MAX_MEM setting is not too large. - -NOTE: this is far from an exhaustive test of the JPEG software; some modules, -such as 1-pass color quantization, are not exercised at all. It's just a -tquick test to give you some confidence that you haven't missed something -major. - - -INSTALLING THE SOFTWARE -======================= - -Once you're done with the above steps, you can install the software by -copying the executable files (cjpeg, djpeg, jpegtran, rdjpgcom, and wrjpgcom) -to wherever you normally install programs. On Unix systems, you'll also want -to put the man pages (cjpeg.1, djpeg.1, jpegtran.1, rdjpgcom.1, wrjpgcom.1) -in the man-page directory. The pre-fab makefiles don't support this step -since there's such a wide variety of installation procedures on different -systems. - -If you generated a Makefile with the "configure" script, you can just say - make install -to install the programs and their man pages into the standard places. -(You'll probably need to be root to do this.) We recommend first saying - make -n install -to see where configure thought the files should go. You may need to edit -the Makefile, particularly if your system's conventions for man page -filenames don't match what configure expects. - -If you want to install the IJG library itself, for use in compiling other -programs besides ours, then you need to put the four include files - jpeglib.h jerror.h jconfig.h jmorecfg.h -into your include-file directory, and put the library file libjpeg.a -(extension may vary depending on system) wherever library files go. -If you generated a Makefile with "configure", it will do what it thinks -is the right thing if you say - make install-lib - - -OPTIONAL STUFF -============== - -Progress monitor: - -If you like, you can #define PROGRESS_REPORT (in jconfig.h) to enable display -of percent-done progress reports. The routine provided in cdjpeg.c merely -prints percentages to stderr, but you can customize it to do something -fancier. - -Utah RLE file format support: - -We distribute the software with support for RLE image files (Utah Raster -Toolkit format) disabled, because the RLE support won't compile without the -Utah library. If you have URT version 3.1 or later, you can enable RLE -support as follows: - 1. #define RLE_SUPPORTED in jconfig.h. - 2. Add a -I option to CFLAGS in the Makefile for the directory - containing the URT .h files (typically the "include" - subdirectory of the URT distribution). - 3. Add -L... -lrle to LDLIBS in the Makefile, where ... specifies - the directory containing the URT "librle.a" file (typically the - "lib" subdirectory of the URT distribution). - -Support for 12-bit-deep pixel data: - -The JPEG standard allows either 8-bit or 12-bit data precision. (For color, -this means 8 or 12 bits per channel, of course.) If you need to work with -deeper than 8-bit data, you can compile the IJG code for 12-bit operation. -To do so: - 1. In jmorecfg.h, define BITS_IN_JSAMPLE as 12 rather than 8. - 2. In jconfig.h, undefine BMP_SUPPORTED, RLE_SUPPORTED, and TARGA_SUPPORTED, - because the code for those formats doesn't handle 12-bit data and won't - even compile. (The PPM code does work, as explained below. The GIF - code works too; it scales 8-bit GIF data to and from 12-bit depth - automatically.) - 3. Compile. Don't expect "make test" to pass, since the supplied test - files are for 8-bit data. - -Currently, 12-bit support does not work on 16-bit-int machines. - -Note that a 12-bit version will not read 8-bit JPEG files, nor vice versa; -so you'll want to keep around a regular 8-bit compilation as well. -(Run-time selection of data depth, to allow a single copy that does both, -is possible but would probably slow things down considerably; it's very low -on our to-do list.) - -The PPM reader (rdppm.c) can read 12-bit data from either text-format or -binary-format PPM and PGM files. Binary-format PPM/PGM files which have a -maxval greater than 255 are assumed to use 2 bytes per sample, LSB first -(little-endian order). As of early 1995, 2-byte binary format is not -officially supported by the PBMPLUS library, but it is expected that a -future release of PBMPLUS will support it. Note that the PPM reader will -read files of any maxval regardless of the BITS_IN_JSAMPLE setting; incoming -data is automatically rescaled to either maxval=255 or maxval=4095 as -appropriate for the cjpeg bit depth. - -The PPM writer (wrppm.c) will normally write 2-byte binary PPM or PGM -format, maxval 4095, when compiled with BITS_IN_JSAMPLE=12. Since this -format is not yet widely supported, you can disable it by compiling wrppm.c -with PPM_NORAWWORD defined; then the data is scaled down to 8 bits to make a -standard 1-byte/sample PPM or PGM file. (Yes, this means still another copy -of djpeg to keep around. But hopefully you won't need it for very long. -Poskanzer's supposed to get that new PBMPLUS release out Real Soon Now.) - -Of course, if you are working with 12-bit data, you probably have it stored -in some other, nonstandard format. In that case you'll probably want to -write your own I/O modules to read and write your format. - -Note that a 12-bit version of cjpeg always runs in "-optimize" mode, in -order to generate valid Huffman tables. This is necessary because our -default Huffman tables only cover 8-bit data. - -Removing code: - -If you need to make a smaller version of the JPEG software, some optional -functions can be removed at compile time. See the xxx_SUPPORTED #defines in -jconfig.h and jmorecfg.h. If at all possible, we recommend that you leave in -decoder support for all valid JPEG files, to ensure that you can read anyone's -output. Taking out support for image file formats that you don't use is the -most painless way to make the programs smaller. Another possibility is to -remove some of the DCT methods: in particular, the "IFAST" method may not be -enough faster than the others to be worth keeping on your machine. (If you -do remove ISLOW or IFAST, be sure to redefine JDCT_DEFAULT or JDCT_FASTEST -to a supported method, by adding a #define in jconfig.h.) - - -OPTIMIZATION -============ - -Unless you own a Cray, you'll probably be interested in making the JPEG -software go as fast as possible. This section covers some machine-dependent -optimizations you may want to try. We suggest that before trying any of -this, you first get the basic installation to pass the self-test step. -Repeat the self-test after any optimization to make sure that you haven't -broken anything. - -The integer DCT routines perform a lot of multiplications. These -multiplications must yield 32-bit results, but none of their input values -are more than 16 bits wide. On many machines, notably the 680x0 and 80x86 -CPUs, a 16x16=>32 bit multiply instruction is faster than a full 32x32=>32 -bit multiply. Unfortunately there is no portable way to specify such a -multiplication in C, but some compilers can generate one when you use the -right combination of casts. See the MULTIPLYxxx macro definitions in -jdct.h. If your compiler makes "int" be 32 bits and "short" be 16 bits, -defining SHORTxSHORT_32 is fairly likely to work. When experimenting with -alternate definitions, be sure to test not only whether the code still works -(use the self-test), but also whether it is actually faster --- on some -compilers, alternate definitions may compute the right answer, yet be slower -than the default. Timing cjpeg on a large PGM (grayscale) input file is the -best way to check this, as the DCT will be the largest fraction of the runtime -in that mode. (Note: some of the distributed compiler-specific jconfig files -already contain #define switches to select appropriate MULTIPLYxxx -definitions.) - -If your machine has sufficiently fast floating point hardware, you may find -that the float DCT method is faster than the integer DCT methods, even -after tweaking the integer multiply macros. In that case you may want to -make the float DCT be the default method. (The only objection to this is -that float DCT results may vary slightly across machines.) To do that, add -"#define JDCT_DEFAULT JDCT_FLOAT" to jconfig.h. Even if you don't change -the default, you should redefine JDCT_FASTEST, which is the method selected -by djpeg's -fast switch. Don't forget to update the documentation files -(usage.doc and/or cjpeg.1, djpeg.1) to agree with what you've done. - -If access to "short" arrays is slow on your machine, it may be a win to -define type JCOEF as int rather than short. This will cost a good deal of -memory though, particularly in some multi-pass modes, so don't do it unless -you have memory to burn and short is REALLY slow. - -If your compiler can compile function calls in-line, make sure the INLINE -macro in jmorecfg.h is defined as the keyword that marks a function -inline-able. Some compilers have a switch that tells the compiler to inline -any function it thinks is profitable (e.g., -finline-functions for gcc). -Enabling such a switch is likely to make the compiled code bigger but faster. - -In general, it's worth trying the maximum optimization level of your compiler, -and experimenting with any optional optimizations such as loop unrolling. -(Unfortunately, far too many compilers have optimizer bugs ... be prepared to -back off if the code fails self-test.) If you do any experimentation along -these lines, please report the optimal settings to jpeg-info@uunet.uu.net so -we can mention them in future releases. Be sure to specify your machine and -compiler version. - - -HINTS FOR SPECIFIC SYSTEMS -========================== - -We welcome reports on changes needed for systems not mentioned here. Submit -'em to jpeg-info@uunet.uu.net. Also, if configure or ckconfig.c is wrong -about how to configure the JPEG software for your system, please let us know. - - -Acorn RISC OS: - -(Thanks to Simon Middleton for these hints on compiling with Desktop C.) -After renaming the files according to Acorn conventions, take a copy of -makefile.ansi, change all occurrences of 'libjpeg.a' to 'libjpeg.o' and -change these definitions as indicated: - -CFLAGS= -throwback -IC: -Wn -LDLIBS=C:o.Stubs -SYSDEPMEM=jmemansi.o -LN=Link -AR=LibFile -c -o - -Also add a new line '.c.o:; $(cc) $< $(cflags) -c -o $@'. Remove the -lines '$(RM) libjpeg.o' and '$(AR2) libjpeg.o' and the 'jconfig.h' -dependency section. - -Copy jconfig.doc to jconfig.h. Edit jconfig.h to define TWO_FILE_COMMANDLINE -and CHAR_IS_UNSIGNED. - -Run the makefile using !AMU not !Make. If you want to use the 'clean' and -'test' makefile entries then you will have to fiddle with the syntax a bit -and rename the test files. - - -Amiga: - -SAS C 6.50 reportedly is too buggy to compile the IJG code properly. -A patch to update to 6.51 is available from SAS or AmiNet FTP sites. - -The supplied config files are set up to use jmemname.c as the memory -manager, with temporary files being created on the device named by -"JPEGTMP:". - - -Atari ST/STE/TT: - -Copy the project files makcjpeg.st, makdjpeg.st, maktjpeg.st, and makljpeg.st -to cjpeg.prj, djpeg.prj, jpegtran.prj, and libjpeg.prj respectively. The -project files should work as-is with Pure C. For Turbo C, change library -filenames "pc..." to "tc..." in each project file. Note that libjpeg.prj -selects jmemansi.c as the recommended memory manager. You'll probably want to -adjust the DEFAULT_MAX_MEM setting --- you want it to be a couple hundred K -less than your normal free memory. Put "#define DEFAULT_MAX_MEM nnnn" into -jconfig.h to do this. - -To use the 68881/68882 coprocessor for the floating point DCT, add the -compiler option "-8" to the project files and replace pcfltlib.lib with -pc881lib.lib in cjpeg.prj and djpeg.prj. Or if you don't have a -coprocessor, you may prefer to remove the float DCT code by undefining -DCT_FLOAT_SUPPORTED in jmorecfg.h (since without a coprocessor, the float -code will be too slow to be useful). In that case, you can delete -pcfltlib.lib from the project files. - -Note that you must make libjpeg.lib before making cjpeg.ttp, djpeg.ttp, -or jpegtran.ttp. You'll have to perform the self-test by hand. - -We haven't bothered to include project files for rdjpgcom and wrjpgcom. -Those source files should just be compiled by themselves; they don't -depend on the JPEG library. - -There is a bug in some older versions of the Turbo C library which causes the -space used by temporary files created with "tmpfile()" not to be freed after -an abnormal program exit. If you check your disk afterwards, you will find -cluster chains that are allocated but not used by a file. This should not -happen in cjpeg/djpeg/jpegtran, since we enable a signal catcher to explicitly -close temp files before exiting. But if you use the JPEG library with your -own code, be sure to supply a signal catcher, or else use a different -system-dependent memory manager. - - -Cray: - -Should you be so fortunate as to be running JPEG on a Cray YMP, there is a -compiler bug in old versions of Cray's Standard C (prior to 3.1). If you -still have an old compiler, you'll need to insert a line reading -"#pragma novector" just before the loop - for (i = 1; i <= (int) htbl->bits[l]; i++) - huffsize[p++] = (char) l; -in fix_huff_tbl (in V5beta1, line 204 of jchuff.c and line 176 of jdhuff.c). -[This bug may or may not still occur with the current IJG code, but it's -probably a dead issue anyway...] - - -HP-UX: - -If you have HP-UX 7.05 or later with the "software development" C compiler, -you should run the compiler in ANSI mode. If using the configure script, -say - ./configure CC='cc -Aa' -(or -Ae if you prefer). If configuring by hand, use makefile.ansi and add -"-Aa" to the CFLAGS line in the makefile. - -If you have a pre-7.05 system, or if you are using the non-ANSI C compiler -delivered with a minimum HP-UX system, then you must use makefile.unix -(and do NOT add -Aa); or just run configure without the CC option. - -On HP 9000 series 800 machines, the HP C compiler is buggy in revisions prior -to A.08.07. If you get complaints about "not a typedef name", you'll have to -use makefile.unix, or run configure without the CC option. - - -Macintosh, generic comments: - -The supplied user-interface files (cjpeg.c, djpeg.c, etc) are set up to -provide a Unix-style command line interface. You can use this interface on -the Mac by means of the ccommand() library routine provided by Metrowerks -CodeWarrior or Think C. This is only appropriate for testing the library, -however; to make a user-friendly equivalent of cjpeg/djpeg you'd really want -to develop a Mac-style user interface. There isn't a complete example -available at the moment, but there are some helpful starting points: -1. Sam Bushell's free "To JPEG" applet provides drag-and-drop conversion to -JPEG under System 7 and later. This only illustrates how to use the -compression half of the library, but it does a very nice job of that part. -The CodeWarrior source code is available from http://www.pobox.com/~jsam. -2. Jim Brunner prepared a Mac-style user interface for both compression and -decompression. Unfortunately, it hasn't been updated since IJG v4, and -the library's API has changed considerably since then. Still it may be of -some help, particularly as a guide to compiling the IJG code under Think C. -Jim's code is available from the Info-Mac archives, at sumex-aim.stanford.edu -or mirrors thereof; see file /info-mac/dev/src/jpeg-convert-c.hqx. - -jmemmac.c is the recommended memory manager back end for Macintosh. It uses -NewPtr/DisposePtr instead of malloc/free, and has a Mac-specific -implementation of jpeg_mem_available(). It also creates temporary files that -follow Mac conventions. (That part of the code relies on System-7-or-later OS -functions. See the comments in jmemmac.c if you need to run it on System 6.) -NOTE that USE_MAC_MEMMGR must be defined in jconfig.h to use jmemmac.c. - -You can also use jmemnobs.c, if you don't care about handling images larger -than available memory. If you use any memory manager back end other than -jmemmac.c, we recommend replacing "malloc" and "free" by "NewPtr" and -"DisposePtr", because Mac C libraries often have peculiar implementations of -malloc/free. (For instance, free() may not return the freed space to the -Mac Memory Manager. This is undesirable for the IJG code because jmemmgr.c -already clumps space requests.) - - -Macintosh, Metrowerks CodeWarrior: - -The Unix-command-line-style interface can be used by defining USE_CCOMMAND. -You'll also need to define TWO_FILE_COMMANDLINE to avoid stdin/stdout. -This means that when using the cjpeg/djpeg programs, you'll have to type the -input and output file names in the "Arguments" text-edit box, rather than -using the file radio buttons. (Perhaps USE_FDOPEN or USE_SETMODE would -eliminate the problem, but I haven't heard from anyone who's tried it.) - -On 680x0 Macs, Metrowerks defines type "double" as a 10-byte IEEE extended -float. jmemmgr.c won't like this: it wants sizeof(ALIGN_TYPE) to be a power -of 2. Add "#define ALIGN_TYPE long" to jconfig.h to eliminate the complaint. - -The supplied configuration file jconfig.mac can be used for your jconfig.h; -it includes all the recommended symbol definitions. If you have AppleScript -installed, you can run the supplied script makeproj.mac to create CodeWarrior -project files for the library and the testbed applications, then build the -library and applications. (Thanks to Dan Sears and Don Agro for this nifty -hack, which saves us from trying to maintain CodeWarrior project files as part -of the IJG distribution...) - - -Macintosh, Think C: - -The documentation in Jim Brunner's "JPEG Convert" source code (see above) -includes detailed build instructions for Think C; it's probably somewhat -out of date for the current release, but may be helpful. - -If you want to build the minimal command line version, proceed as follows. -You'll have to prepare project files for the programs; we don't include any -in the distribution since they are not text files. Use the file lists in -any of the supplied makefiles as a guide. Also add the ANSI and Unix C -libraries in a separate segment. You may need to divide the JPEG files into -more than one segment; we recommend dividing compression and decompression -modules. Define USE_CCOMMAND in jconfig.h so that the ccommand() routine is -called. You must also define TWO_FILE_COMMANDLINE because stdin/stdout -don't handle binary data correctly. - -On 680x0 Macs, Think C defines type "double" as a 12-byte IEEE extended float. -jmemmgr.c won't like this: it wants sizeof(ALIGN_TYPE) to be a power of 2. -Add "#define ALIGN_TYPE long" to jconfig.h to eliminate the complaint. - -jconfig.mac should work as a jconfig.h configuration file for Think C, -but the makeproj.mac AppleScript script is specific to CodeWarrior. Sorry. - - -MIPS R3000: - -MIPS's cc version 1.31 has a rather nasty optimization bug. Don't use -O -if you have that compiler version. (Use "cc -V" to check the version.) -Note that the R3000 chip is found in workstations from DEC and others. - - -MS-DOS, generic comments for 16-bit compilers: - -The IJG code is designed to work well in 80x86 "small" or "medium" memory -models (i.e., data pointers are 16 bits unless explicitly declared "far"; -code pointers can be either size). You may be able to use small model to -compile cjpeg or djpeg by itself, but you will probably have to use medium -model for any larger application. This won't make much difference in -performance. You *will* take a noticeable performance hit if you use a -large-data memory model, and you should avoid "huge" model if at all -possible. Be sure that NEED_FAR_POINTERS is defined in jconfig.h if you use -a small-data memory model; be sure it is NOT defined if you use a large-data -model. (The supplied makefiles and jconfig files for Borland and Microsoft C -compile in medium model and define NEED_FAR_POINTERS.) - -The DOS-specific memory manager, jmemdos.c, should be used if possible. -It needs some assembly-code routines which are in jmemdosa.asm; make sure -your makefile assembles that file and includes it in the library. If you -don't have a suitable assembler, you can get pre-assembled object files for -jmemdosa by FTP from ftp.uu.net:/graphics/jpeg/jdosaobj.zip. (DOS-oriented -distributions of the IJG source code often include these object files.) - -When using jmemdos.c, jconfig.h must define USE_MSDOS_MEMMGR and must set -MAX_ALLOC_CHUNK to less than 64K (65520L is a typical value). If your -C library's far-heap malloc() can't allocate blocks that large, reduce -MAX_ALLOC_CHUNK to whatever it can handle. - -If you can't use jmemdos.c for some reason --- for example, because you -don't have an assembler to assemble jmemdosa.asm --- you'll have to fall -back to jmemansi.c or jmemname.c. You'll probably still need to set -MAX_ALLOC_CHUNK in jconfig.h, because most DOS C libraries won't malloc() -more than 64K at a time. IMPORTANT: if you use jmemansi.c or jmemname.c, -you will have to compile in a large-data memory model in order to get the -right stdio library. Too bad. - -wrjpgcom needs to be compiled in large model, because it malloc()s a 64KB -work area to hold the comment text. If your C library's malloc can't -handle that, reduce MAX_COM_LENGTH as necessary in wrjpgcom.c. - -Most MS-DOS compilers treat stdin/stdout as text files, so you must use -two-file command line style. But if your compiler has either fdopen() or -setmode(), you can use one-file style if you like. To do this, define -USE_SETMODE or USE_FDOPEN so that stdin/stdout will be set to binary mode. -(USE_SETMODE seems to work with more DOS compilers than USE_FDOPEN.) You -should test that I/O through stdin/stdout produces the same results as I/O -to explicitly named files... the "make test" procedures in the supplied -makefiles do NOT use stdin/stdout. - - -MS-DOS, generic comments for 32-bit compilers: - -None of the above comments about memory models apply if you are using a -32-bit flat-memory-space environment, such as DJGPP or Watcom C. (And you -should use one if you have it, as performance will be much better than -8086-compatible code!) For flat-memory-space compilers, do NOT define -NEED_FAR_POINTERS, and do NOT use jmemdos.c. Use jmemnobs.c if the -environment supplies adequate virtual memory, otherwise use jmemansi.c or -jmemname.c. - -You'll still need to be careful about binary I/O through stdin/stdout. -See the last paragraph of the previous section. - - -MS-DOS, Borland C: - -Be sure to convert all the source files to DOS text format (CR/LF newlines). -Although Borland C will often work OK with unmodified Unix (LF newlines) -source files, sometimes it will give bogus compile errors. -"Illegal character '#'" is the most common such error. (This is true with -Borland C 3.1, but perhaps is fixed in newer releases.) - -If you want one-file command line style, just undefine TWO_FILE_COMMANDLINE. -jconfig.bcc already includes #define USE_SETMODE to make this work. -(fdopen does not work correctly.) - - -MS-DOS, Microsoft C: - -makefile.mc6 works with Microsoft C, DOS Visual C++, etc. It should only -be used if you want to build a 16-bit (small or medium memory model) program. - -If you want one-file command line style, just undefine TWO_FILE_COMMANDLINE. -jconfig.mc6 already includes #define USE_SETMODE to make this work. -(fdopen does not work correctly.) - -Note that this makefile assumes that the working copy of itself is called -"makefile". If you want to call it something else, say "makefile.mak", -be sure to adjust the dependency line that reads "$(RFILE) : makefile". -Otherwise the make will fail because it doesn't know how to create "makefile". -Worse, some releases of Microsoft's make utilities give an incorrect error -message in this situation. - -Old versions of MS C fail with an "out of macro expansion space" error -because they can't cope with the macro TRACEMS8 (defined in jerror.h). -If this happens to you, the easiest solution is to change TRACEMS8 to -expand to nothing. You'll lose the ability to dump out JPEG coefficient -tables with djpeg -debug -debug, but at least you can compile. - -Original MS C 6.0 is very buggy; it compiles incorrect code unless you turn -off optimization entirely (remove -O from CFLAGS). 6.00A is better, but it -still generates bad code if you enable loop optimizations (-Ol or -Ox). - -MS C 8.0 crashes when compiling jquant1.c with optimization switch /Oo ... -which is on by default. To work around this bug, compile that one file -with /Oo-. - - -Microsoft Windows (all versions), generic comments: - -Some Windows system include files define typedef boolean as "unsigned char". -The IJG code also defines typedef boolean, but we make it "int" by default. -This doesn't affect the IJG programs because we don't import those Windows -include files. But if you use the JPEG library in your own program, and some -of your program's files import one definition of boolean while some import the -other, you can get all sorts of mysterious problems. A good preventive step -is to make the IJG library use "unsigned char" for boolean. To do that, -add something like this to your jconfig.h file: - /* Define "boolean" as unsigned char, not int, per Windows custom */ - #ifndef __RPCNDR_H__ /* don't conflict if rpcndr.h already read */ - typedef unsigned char boolean; - #endif - #define HAVE_BOOLEAN /* prevent jmorecfg.h from redefining it */ -(This is already in jconfig.vc, by the way.) - -windef.h contains the declarations - #define far - #define FAR far -Since jmorecfg.h tries to define FAR as empty, you may get a compiler -warning if you include both jpeglib.h and windef.h (which windows.h -includes). To suppress the warning, you can put "#ifndef FAR"/"#endif" -around the line "#define FAR" in jmorecfg.h. - -When using the library in a Windows application, you will almost certainly -want to modify or replace the error handler module jerror.c, since our -default error handler does a couple of inappropriate things: - 1. it tries to write error and warning messages on stderr; - 2. in event of a fatal error, it exits by calling exit(). - -A simple stopgap solution for problem 1 is to replace the line - fprintf(stderr, "%s\n", buffer); -(in output_message in jerror.c) with - MessageBox(GetActiveWindow(),buffer,"JPEG Error",MB_OK|MB_ICONERROR); -It's highly recommended that you at least do that much, since otherwise -error messages will disappear into nowhere. (Beginning with IJG v6b, this -code is already present in jerror.c; just define USE_WINDOWS_MESSAGEBOX in -jconfig.h to enable it.) - -The proper solution for problem 2 is to return control to your calling -application after a library error. This can be done with the setjmp/longjmp -technique discussed in libjpeg.doc and illustrated in example.c. (NOTE: -some older Windows C compilers provide versions of setjmp/longjmp that -don't actually work under Windows. You may need to use the Windows system -functions Catch and Throw instead.) - -The recommended memory manager under Windows is jmemnobs.c; in other words, -let Windows do any virtual memory management needed. You should NOT use -jmemdos.c nor jmemdosa.asm under Windows. - -For Windows 3.1, we recommend compiling in medium or large memory model; -for newer Windows versions, use a 32-bit flat memory model. (See the MS-DOS -sections above for more info about memory models.) In the 16-bit memory -models only, you'll need to put - #define MAX_ALLOC_CHUNK 65520L /* Maximum request to malloc() */ -into jconfig.h to limit allocation chunks to 64Kb. (Without that, you'd -have to use huge memory model, which slows things down unnecessarily.) -jmemnobs.c works without modification in large or flat memory models, but to -use medium model, you need to modify its jpeg_get_large and jpeg_free_large -routines to allocate far memory. In any case, you might like to replace -its calls to malloc and free with direct calls on Windows memory allocation -functions. - -You may also want to modify jdatasrc.c and jdatadst.c to use Windows file -operations rather than fread/fwrite. This is only necessary if your C -compiler doesn't provide a competent implementation of C stdio functions. - -You might want to tweak the RGB_xxx macros in jmorecfg.h so that the library -will accept or deliver color pixels in BGR sample order, not RGB; BGR order -is usually more convenient under Windows. Note that this change will break -the sample applications cjpeg/djpeg, but the library itself works fine. - - -Many people want to convert the IJG library into a DLL. This is reasonably -straightforward, but watch out for the following: - - 1. Don't try to compile as a DLL in small or medium memory model; use -large model, or even better, 32-bit flat model. Many places in the IJG code -assume the address of a local variable is an ordinary (not FAR) pointer; -that isn't true in a medium-model DLL. - - 2. Microsoft C cannot pass file pointers between applications and DLLs. -(See Microsoft Knowledge Base, PSS ID Number Q50336.) So jdatasrc.c and -jdatadst.c don't work if you open a file in your application and then pass -the pointer to the DLL. One workaround is to make jdatasrc.c/jdatadst.c -part of your main application rather than part of the DLL. - - 3. You'll probably need to modify the macros GLOBAL() and EXTERN() to -attach suitable linkage keywords to the exported routine names. Similarly, -you'll want to modify METHODDEF() and JMETHOD() to ensure function pointers -are declared in a way that lets application routines be called back through -the function pointers. These macros are in jmorecfg.h. Typical definitions -for a 16-bit DLL are: - #define GLOBAL(type) type _far _pascal _loadds _export - #define EXTERN(type) extern type _far _pascal _loadds - #define METHODDEF(type) static type _far _pascal - #define JMETHOD(type,methodname,arglist) \ - type (_far _pascal *methodname) arglist -For a 32-bit DLL you may want something like - #define GLOBAL(type) __declspec(dllexport) type - #define EXTERN(type) extern __declspec(dllexport) type -Although not all the GLOBAL routines are actually intended to be called by -the application, the performance cost of making them all DLL entry points is -negligible. - -The unmodified IJG library presents a very C-specific application interface, -so the resulting DLL is only usable from C or C++ applications. There has -been some talk of writing wrapper code that would present a simpler interface -usable from other languages, such as Visual Basic. This is on our to-do list -but hasn't been very high priority --- any volunteers out there? - - -Microsoft Windows, Borland C: - -The provided jconfig.bcc should work OK in a 32-bit Windows environment, -but you'll need to tweak it in a 16-bit environment (you'd need to define -NEED_FAR_POINTERS and MAX_ALLOC_CHUNK). Beware that makefile.bcc will need -alteration if you want to use it for Windows --- in particular, you should -use jmemnobs.c not jmemdos.c under Windows. - -Borland C++ 4.5 fails with an internal compiler error when trying to compile -jdmerge.c in 32-bit mode. If enough people complain, perhaps Borland will fix -it. In the meantime, the simplest known workaround is to add a redundant -definition of the variable range_limit in h2v1_merged_upsample(), at the head -of the block that handles odd image width (about line 268 in v6 jdmerge.c): - /* If image width is odd, do the last output column separately */ - if (cinfo->output_width & 1) { - register JSAMPLE * range_limit = cinfo->sample_range_limit; /* ADD THIS */ - cb = GETJSAMPLE(*inptr1); -Pretty bizarre, especially since the very similar routine h2v2_merged_upsample -doesn't trigger the bug. -Recent reports suggest that this bug does not occur with "bcc32a" (the -Pentium-optimized version of the compiler). - -Another report from a user of Borland C 4.5 was that incorrect code (leading -to a color shift in processed images) was produced if any of the following -optimization switch combinations were used: - -Ot -Og - -Ot -Op - -Ot -Om -So try backing off on optimization if you see such a problem. (Are there -several different releases all numbered "4.5"??) - - -Microsoft Windows, Microsoft Visual C++: - -jconfig.vc should work OK with any Microsoft compiler for a 32-bit memory -model. makefile.vc is intended for command-line use. (If you are using -the Developer Studio environment, you may prefer the DevStudio project -files; see below.) - -Some users feel that it's easier to call the library from C++ code if you -force VC++ to treat the library as C++ code, which you can do by renaming -all the *.c files to *.cpp (and adjusting the makefile to match). This -avoids the need to put extern "C" { ... } around #include "jpeglib.h" in -your C++ application. - - -Microsoft Windows, Microsoft Developer Studio: - -We include makefiles that should work as project files in DevStudio 4.2 or -later. There is a library makefile that builds the IJG library as a static -Win32 library, and an application makefile that builds the sample applications -as Win32 console applications. (Even if you only want the library, we -recommend building the applications so that you can run the self-test.) - -To use: -1. Copy jconfig.vc to jconfig.h, makelib.ds to jpeg.mak, and - makeapps.ds to apps.mak. (Note that the renaming is critical!) -2. Click on the .mak files to construct project workspaces. - (If you are using DevStudio more recent than 4.2, you'll probably - get a message saying that the makefiles are being updated.) -3. Build the library project, then the applications project. -4. Move the application .exe files from `app`\Release to an - appropriate location on your path. -5. To perform the self-test, execute the command line - NMAKE /f makefile.vc test - - -OS/2, Borland C++: - -Watch out for optimization bugs in older Borland compilers; you may need -to back off the optimization switch settings. See the comments in -makefile.bcc. - - -SGI: - -On some SGI systems, you may need to set "AR2= ar -ts" in the Makefile. -If you are using configure, you can do this by saying - ./configure RANLIB='ar -ts' -This change is not needed on all SGIs. Use it only if the make fails at the -stage of linking the completed programs. - -On the MIPS R4000 architecture (Indy, etc.), the compiler option "-mips2" -reportedly speeds up the float DCT method substantially, enough to make it -faster than the default int method (but still slower than the fast int -method). If you use -mips2, you may want to alter the default DCT method to -be float. To do this, put "#define JDCT_DEFAULT JDCT_FLOAT" in jconfig.h. - - -VMS: - -On an Alpha/VMS system with MMS, be sure to use the "/Marco=Alpha=1" -qualifier with MMS when building the JPEG package. - -VAX/VMS v5.5-1 may have problems with the test step of the build procedure -reporting differences when it compares the original and test images. If the -error points to the last block of the files, it is most likely bogus and may -be safely ignored. It seems to be because the files are Stream_LF and -Backup/Compare has difficulty with the (presumably) null padded files. -This problem was not observed on VAX/VMS v6.1 or AXP/VMS v6.1. |