ChangeLog.txt

1.1.90 (1.2 beta1)
==================

[1] Added a JNI wrapper for TurboJPEG/OSS.  See java/README for more details.

[2] TurboJPEG/OSS can now scale down images during decompression.

[3] Added SIMD routines for RGB-to-grayscale color conversion, which
significantly improves the performance of grayscale JPEG compression from an
RGB source image.

[4] Improved performance for non-x86 machines.

[5] Added a function to the TurboJPEG API which performs lossless transforms.
This function uses the same back end as jpegtran, but it performs transcoding
entirely in memory and allows multiple transforms and/or crop operations to be
batched together, so the source coefficients only need to be read once.  This
is useful when generating image tiles from a single source JPEG.

[6] Modified jpgtest to benchmark the new scaled decompression and lossless
transform features in TurboJPEG/OSS.

[7] Added support for 4:4:0 (transposed 4:2:2) subsampling in TurboJPEG, which
was necessary in order for it to read 4:2:2 JPEG files that had been losslessly
transposed or rotated 90 degrees.

[8] All legacy VirtualGL code has been re-factored, and this has allowed
libjpeg-turbo, in its entirety, to be re-licensed under a BSD-style license.

[9] libjpeg-turbo can now be built with YASM.

[10] Added SIMD acceleration for ARM Linux and iOS platforms that support
NEON instructions.

[11] Refactored the TurboJPEG C API so that it uses pixel formats to define the
size and component order of the uncompressed source/destination images as well
as uses the libjpeg memory source and destination managers.  The latter allows
the TurboJPEG compressor to grow the JPEG buffer as necessary.

[12] Eliminated errors in the output of jpegtran on Windows that occurred when
the application was invoked using I/O redirection
(jpegtran <input.jpg >output.jpg).

[13] The inclusion of libjpeg v7 and v8 emulation as well as arithmetic coding
support in libjpeg-turbo v1.1.0 introduced several new error constants in
jerror.h, and these were mistakenly enabled for all emulation modes, causing
the error enum in libjpeg-turbo to sometimes have different values than the
same enum in libjpeg.  This represents an ABI incompatibility, and it caused
problems with rare applications that took specific action based on a particular
error value.  The fix was to include the new error constants conditionally
based on whether libjpeg v7 or v8 emulation was enabled.

[14] Fixed an issue whereby Windows applications that used libjpeg-turbo would
fail to compile if the Windows system headers were included before jpeglib.h.
This issue was caused by a conflict in the definition of the INT32 type.

[15] Implemented a more efficient version of TJBUFSIZE() which computes a
worst-case JPEG size based on the level of chrominance subsampling.

[16] Fixed 32-bit supplementary package for amd64 Debian systems which was
broken by enhancements to the packaging system in 1.1.

[17] Support for decoding JPEG images that use the CMYK or YCCK colorspaces.


1.1.1
=====

[1] Fixed a 1-pixel error in row 0, column 21 of the luminance plane generated
by tjEncodeYUV().

[2] libjpeg-turbo's accelerated Huffman decoder previously ignored unexpected
markers found in the middle of the JPEG data stream during decompression.  It
will now hand off decoding of a particular block to the unaccelerated Huffman
decoder if an unexpected marker is found, so that the unaccelerated Huffman
decoder can generate an appropriate warning.

[3] Older versions of MinGW64 prefixed symbol names with underscores by
default, which differed from the behavior of 64-bit Visual C++.  MinGW64 1.0
has adopted the behavior of 64-bit Visual C++ as the default, so to accommodate
this, the libjpeg-turbo SIMD function names are no longer prefixed with an
underscore when building with MinGW64.  This means that, when building
libjpeg-turbo with older versions of MinGW64, you will now have to add
-fno-leading-underscore to the CFLAGS.

[4] Fixed a regression bug in the NSIS script that caused the Windows installer
build to fail when using the Visual Studio IDE.

[5] Fixed a bug in jpeg_read_coefficients() whereby it would not initialize
cinfo->image_width and cinfo->image_height if libjpeg v7 or v8 emulation was
enabled.  This specifically caused the jpegoptim program to fail if it was
linked against a version of libjpeg-turbo that was built with libjpeg v7 or v8
emulation.

[6] Eliminated excessive I/O overhead that occurred when reading BMP files in
cjpeg.

[7] Eliminated errors in the output of cjpeg on Windows that occurred when the
application was invoked using I/O redirection (cjpeg <inputfile >output.jpg).


1.1.0
=====

[1] The algorithm used by the SIMD quantization function cannot produce correct
results when the JPEG quality is >= 98 and the fast integer forward DCT is
used.  Thus, the non-SIMD quantization function is now used for those cases,
and libjpeg-turbo should now produce identical output to libjpeg v6b in all
cases.

[2] Despite the above, the fast integer forward DCT still degrades somewhat for
JPEG qualities greater than 95, so TurboJPEG/OSS will now automatically use the
slow integer forward DCT when generating JPEG images of quality 96 or greater.
This reduces compression performance by as much as 15% for these high-quality
images but is necessary to ensure that the images are perceptually lossless.
It also ensures that the library can avoid the performance pitfall created by
[1].

[3] Ported jpgtest.cxx to pure C to avoid the need for a C++ compiler.

[4] Fixed visual artifacts in grayscale JPEG compression caused by a typo in
the RGB-to-luminance lookup tables.

[5] The Windows distribution packages now include the libjpeg run-time programs
(cjpeg, etc.)

[6] All packages now include jpgtest.

[7] The TurboJPEG dynamic library now uses versioned symbols.

[8] Added two new TurboJPEG API functions, tjEncodeYUV() and
tjDecompressToYUV(), to replace the somewhat hackish TJ_YUV flag.


1.0.90 (1.1 beta1)
==================

[1] Added emulation of the libjpeg v7 and v8 APIs and ABIs.  See
README-turbo.txt for more details.  This feature was sponsored by CamTrace SAS.

[2] Created a new CMake-based build system for the Visual C++ and MinGW builds.

[3] TurboJPEG/OSS can now compress from/decompress to grayscale bitmaps.

[4] jpgtest can now be used to test decompression performance with existing
JPEG images.

[5] If the default install prefix (/opt/libjpeg-turbo) is used, then
'make install' now creates /opt/libjpeg-turbo/lib32 and
/opt/libjpeg-turbo/lib64 sym links to duplicate the behavior of the binary
packages.

[6] All symbols in the libjpeg-turbo dynamic library are now versioned, even
when the library is built with libjpeg v6b emulation.

[7] Added arithmetic encoding and decoding support (can be disabled with
configure or CMake options)

[8] Added a TJ_YUV flag to TurboJPEG/OSS which causes both the compressor and
decompressor to output planar YUV images.

[9] Added an extended version of tjDecompressHeader() to TurboJPEG/OSS which
allows the caller to determine the type of subsampling used in a JPEG image.

[10] Added further protections against invalid Huffman codes.


1.0.1
=====

[1] The Huffman decoder will now handle erroneous Huffman codes (for instance,
from a corrupt JPEG image.)  Previously, these would cause libjpeg-turbo to
crash under certain circumstances.

[2] Fixed typo in SIMD dispatch routines which was causing 4:2:2 upsampling to
be used instead of 4:2:0 when decompressing JPEG images using SSE2 code.

[3] configure script will now automatically determine whether the
INCOMPLETE_TYPES_BROKEN macro should be defined.


1.0.0
=====

[1] 2983700: Further FreeBSD build tweaks (no longer necessary to specify
--host when configuring on a 64-bit system)

[2] Created sym. links in the Unix/Linux packages so that the TurboJPEG
include file can always be found in /opt/libjpeg-turbo/include, the 32-bit
static libraries can always be found in /opt/libjpeg-turbo/lib32, and the
64-bit static libraries can always be found in /opt/libjpeg-turbo/lib64.

[3] The Unix/Linux distribution packages now include the libjpeg run-time
programs (cjpeg, etc.) and man pages.

[4] Created a 32-bit supplementary package for amd64 Debian systems which
contains just the 32-bit libjpeg-turbo libraries.

[5] Moved the libraries from */lib32 to */lib in the i386 Debian package.

[6] Include distribution package for Cygwin

[7] No longer necessary to specify --without-simd on non-x86 architectures, and
unit tests now work on those architectures.


0.0.93
======

[1] 2982659, Fixed x86-64 build on FreeBSD systems

[2] 2988188: Added support for Windows 64-bit systems


0.0.91
======

[1] Added documentation to .deb packages

[2] 2968313: Fixed data corruption issues when decompressing large JPEG images
and/or using buffered I/O with the libjpeg-turbo decompressor


0.0.90
======

Initial release