71539b3e13
* commit 'b8d044a666056d4d8d28d7a5d0805ac32b619b36': (58 commits) Big oops. wrjpgcom on Windows was being built using the rdjpgcom source. Prevent a buffer overrun if the comment begins with a literal quote character and the string exceeds 65k characters. Also prevent comments longer than 65k characters from being written, since this will produce an incorrect JPEG file. Remove VMS-specific code Our copyright string is longer than JMSG_LENGTH_MAX, and this was causing a buffer overrun if output_message() was called with msg_code set to JMSG_COPYRIGHT, or if format_message() was called with msg_code set to JMSG_COPYRIGHT and with a buffer of length JMSG_LENGTH_MAX. We don't support non-ANSI C compilers Allow for building the MIPS DSPr2 extensions if the host is mips-* as well as mipsel-*. The DSPr2 extensions are little endian, so we still have to check that the compiler defines __MIPSEL__ before enabling them. This paves the way for supporting big-endian MIPS, and in the near term, it allows the SIMD extensions to be built with Sourcery CodeBench. SIMD-accelerated int upsample routine for MIPS DSPr2 Fix MIPS build 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. 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. Further copyright header cleanup Further copyright header cleanup Get rid of the HAVE_PROTOTYPES configuration option, as well as the related JMETHOD and JPP macros. libjpeg-turbo has never supported compilers that don't handle prototypes. Doing so requires ansi2knr, which isn't even supported in the IJG code anymore. Remove all of the NEED_SHORT_EXTERNAL_NAMES stuff. There is scant information available as to which linkers ever had a 15-character global symbol name limit. AFAICT, it might have been a VMS and/or a.out BSD thing, but none of those platforms have ever been supported by libjpeg-turbo (nor are such systems supported by other open source libraries of this nature.) Clean up code formatting in the SIMD interface functions SIMD-accelerated NULL convert routine for MIPS DSPr2 Fix build, which was broken by the checkin of the MIPS DSPr2 accelerated smooth downsampling routine. Until/unless other platforms include SIMD support for that function, it's just easier to #ifdef around it rather than adding stubs for the other platforms. Fix error in MIPS DSPr2 accelerated smooth downsample routine SIMD-accelerated h2v2 smooth downsampling routine for MIPS DSPr2 Minor tweak to improve code readability ... Conflicts: BUILDING.txt CMakeLists.txt Makefile.am cdjpeg.h cjpeg.1 cjpeg.c configure.ac djpeg.1 example.c jccoefct.c jcdctmgr.c jchuff.c jchuff.h jcinit.c jcmaster.c jcparam.c jcphuff.c jidctflt.c jpegint.h jpeglib.h jversion.h libjpeg.txt rdswitch.c simd/CMakeLists.txt tjbench.c turbojpeg.c usage.txt wrjpgcom.c
TurboJPEG Java Wrapper
======================
The TurboJPEG shared library can optionally be built with a Java Native
Interface wrapper, which allows the library to be loaded and used directly from
Java applications. The Java front end for this is defined in several classes
located under org/libjpegturbo/turbojpeg. The source code for these Java
classes is licensed under a BSD-style license, so the files can be incorporated
directly into both open source and proprietary projects without restriction. A
Java archive (JAR) file containing these classes is also shipped with the
"official" distribution packages of libjpeg-turbo.
TJExample.java, which should also be located in the same directory as this
README file, demonstrates how to use the TurboJPEG Java API to compress and
decompress JPEG images in memory.
Performance Pitfalls
--------------------
The TurboJPEG Java API defines several convenience methods that can allocate
image buffers or instantiate classes to hold the result of compress,
decompress, or transform operations. However, if you use these methods, then
be mindful of the amount of new data you are creating on the heap. It may be
necessary to manually invoke the garbage collector to prevent heap exhaustion
or to prevent performance degradation. Background garbage collection can kill
performance, particularly in a multi-threaded environment (Java pauses all
threads when the GC runs.)
The TurboJPEG Java API always gives you the option of pre-allocating your own
source and destination buffers, which allows you to re-use those buffers for
compressing/decompressing multiple images. If the image sequence you are
compressing or decompressing consists of images of the same size, then
pre-allocating the buffers is recommended.
Installation Directory
----------------------
The TurboJPEG Java Wrapper will look for the TurboJPEG JNI library
(libturbojpeg.so, libturbojpeg.jnilib, or turbojpeg.dll) in the system library
paths or in any paths specified in LD_LIBRARY_PATH (Un*x), DYLD_LIBRARY_PATH
(Mac), or PATH (Windows.) Failing this, on Un*x and Mac systems, the wrapper
will look for the JNI library under the library directory configured when
libjpeg-turbo was built. If that library directory is
/opt/libjpeg-turbo/lib32, then /opt/libjpeg-turbo/lib64 is also searched, and
vice versa.
If you installed the JNI library into another directory, then you will need
to pass an argument of -Djava.library.path={path_to_JNI_library} to java, or
manipulate LD_LIBRARY_PATH, DYLD_LIBRARY_PATH, or PATH to include the directory
containing the JNI library.