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
Place the authors in the following order:
* libjpeg-turbo authors (2009-) in descending order of the date of their
most recent contribution to the project, then in ascending order of
the date of their first contribution to the project
* Upstream authors in descending order of the date of the first
inclusion of their code (this indicates that their code serves as the
foundation of this code.)
This also adds Siarhei to the author list, since he contributed ARM SIMD
code both as a Nokia employee and more recently as an independent
developer.
Full-color compression speedups relative to libjpeg-turbo 1.4.2:
2.8 GHz Intel Xeon W3530, Linux, 64-bit: 2.2-18% (avg. 9.5%)
2.8 GHz Intel Xeon W3530, Linux, 32-bit: 10-25% (avg. 17%)
2.3 GHz AMD A10-4600M APU, Linux, 64-bit: 4.9-17% (avg. 11%)
2.3 GHz AMD A10-4600M APU, Linux, 32-bit: 8.8-19% (avg. 15%)
3.0 GHz Intel Core i7, OS X, 64-bit: 3.5-16% (avg. 10%)
3.0 GHz Intel Core i7, OS X, 32-bit: 4.8-14% (avg. 11%)
2.6 GHz AMD Athlon 64 X2 5050e:
Performance-neutral (give or take a few percent)
Full-color compression speedups relative to IPP:
2.8 GHz Intel Xeon W3530, Linux, 64-bit: 4.8-34% (avg. 19%)
2.8 GHz Intel Xeon W3530, Linux, 32-bit: -19%-7.0% (avg. -7.0%)
Refer to #42 for discussion. Numerous other approaches were attempted,
but this one proved to be the most performant across all platforms.
This commit also fixes#3 (works around, really-- the clang-compiled version
of jchuff.c still performs 20% worse than its GCC-compiled counterpart, but
that code is now bypassed by the new SSE2 Huffman algorithm.)
Based on:
2cb4d4133036c94e050d
Fix a regression introduced in 1.4.1 that prevented 32-bit and 64-bit
libjpeg-turbo RPMs from being installed simultaneously on recent Red
Hat/Fedora distributions. This was due to the addition of the
SIZEOF_SIZE_T macro in jconfig.h, which allows the Huffman codec to
determine the word size at compile time. Since that macro differs
between 32-bit and 64-bit builds, this caused a conflict between the
i386 and x86_64 RPMs (any differing files, other than executables, are
not allowed when 32-bit and 64-bit RPMs are installed simultaneously.)
Since the macro is used only internally, it has been moved into
jconfigint.h.
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.
We can't simply increase JMSG_LENGTH_MAX, because it is part of the libjpeg API, and it is generally assumed that a buffer of this length will be passed to format_message(). Thus, the easiest solution is simply to use a shorter copyright string for JMSG_COPYRIGHT.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1318 632fc199-4ca6-4c93-a231-07263d6284db