Update libjpeg_turbo to 1.4.90 from https://github.com/libjpeg-turbo/

BUILDING.md

+Building on Un*x Platforms (including Cygwin and OS X)
+=======================================================
+
+
+Build Requirements
+------------------
+
+- autoconf 2.56 or later
+
+- automake 1.7 or later
+
+- libtool 1.4 or later
+  * If using Xcode 4.3 or later on OS X, autoconf and automake are no longer
+    provided.  The easiest way to obtain them is from
+    [MacPorts](http://www.MacPorts.org).
+
+- NASM or YASM (if building x86 or x86-64 SIMD extensions)
+  * NASM 0.98, or 2.01 or later is required for an x86 build (0.99 and 2.00 do
+    not work properly with libjpeg-turbo's x86 SIMD code.)
+  * NASM 2.00 or later is required for an x86-64 build.
+  * NASM 2.07, or 2.11.09 or later is required for an x86-64 Mac build
+    (2.11.08 does not work properly with libjpeg-turbo's x86-64 SIMD code when
+    building macho64 objects.)  NASM or YASM can be obtained from
+    [MacPorts](http://www.MacPorts.org).
+
+  The binary RPMs released by the NASM project do not work on older Linux
+  systems, such as Red Hat Enterprise Linux 4.  On such systems, you can
+   easily build and install NASM from a source RPM by downloading one of the
+  SRPMs from
+
+  http://www.nasm.us/pub/nasm/releasebuilds
+
+  and executing the following as root:
+
+        ARCH=`uname -m`
+        rpmbuild --rebuild nasm-{version}.src.rpm
+        rpm -Uvh /usr/src/redhat/RPMS/$ARCH/nasm-{version}.$ARCH.rpm
+
+  NOTE: the NASM build will fail if texinfo is not installed.
+
+- GCC v4.1 (or later) or clang recommended for best performance
+
+- If building the TurboJPEG Java wrapper, JDK or OpenJDK 1.5 or later is
+  required.  Some systems, such as Solaris 10 and later and Red Hat Enterprise
+  Linux 5 and later, have this pre-installed.  On OS X 10.5 and 10.6, it will
+  be necessary to install the Java Developer Package, which can be downloaded
+  from http://developer.apple.com/downloads (Apple ID required.)  For other
+  systems, you can obtain the Oracle Java Development Kit from
+  http://www.java.com.
+
+
+Out-of-Tree Builds
+------------------
+
+Binary objects, libraries, and executables are generated in the same directory
+from which `configure` was executed (the "binary directory"), and this
+directory need not necessarily be the same as the libjpeg-turbo source
+directory.  You can create multiple independent binary directories, in which
+different versions of libjpeg-turbo can be built from the same source tree
+using different compilers or settings.  In the sections below,
+*{build_directory}* refers to the binary directory, whereas
+*{source_directory}* refers to the libjpeg-turbo source directory.  For in-tree
+builds, these directories are the same.
+
+
+Building libjpeg-turbo
+----------------------
+
+The following procedure will build libjpeg-turbo on Linux, FreeBSD, Cygwin, and
+Solaris/x86 systems (on Solaris, this generates a 32-bit library.  See below
+for 64-bit build instructions.)
+
+    cd {source_directory}
+    autoreconf -fiv
+    cd {build_directory}
+    sh {source_directory}/configure [additional configure flags]
+    make
+
+NOTE: Running autoreconf in the source directory is not necessary if building
+libjpeg-turbo from one of the official release tarballs.
+
+This will generate the following files under .libs/:
+
+**libjpeg.a**
+Static link library for the libjpeg API
+
+**libjpeg.so.{version}** (Linux, Unix)
+**libjpeg.{version}.dylib** (OS X)
+**cygjpeg-{version}.dll** (Cygwin)
+Shared library for the libjpeg API
+
+By default, *{version}* is 62.1.0, 7.1.0, or 8.0.2, depending on whether
+libjpeg v6b (default), v7, or v8 emulation is enabled.  If using Cygwin,
+*{version}* is 62, 7, or 8.
+
+**libjpeg.so** (Linux, Unix)
+**libjpeg.dylib** (OS X)
+Development symlink for the libjpeg API
+
+**libjpeg.dll.a** (Cygwin)
+Import library for the libjpeg API
+
+**libturbojpeg.a**
+Static link library for the TurboJPEG API
+
+**libturbojpeg.so.0.1.0** (Linux, Unix)
+**libturbojpeg.0.1.0.dylib** (OS X)
+**cygturbojpeg-0.dll** (Cygwin)
+Shared library for the TurboJPEG API
+
+**libturbojpeg.so** (Linux, Unix)
+**libturbojpeg.dylib** (OS X)
+Development symlink for the TurboJPEG API
+
+**libturbojpeg.dll.a** (Cygwin)
+Import library for the TurboJPEG API
+
+
+### libjpeg v7 or v8 API/ABI Emulation
+
+Add `--with-jpeg7` to the `configure` command line to build a version of
+libjpeg-turbo that is API/ABI-compatible with libjpeg v7.  Add `--with-jpeg8`
+to the `configure` command to build a version of libjpeg-turbo that is
+API/ABI-compatible with libjpeg v8.  See [README.md](README.md) for more
+information on libjpeg v7 and v8 emulation.
+
+
+### In-Memory Source/Destination Managers
+
+When using libjpeg v6b or v7 API/ABI emulation, add `--without-mem-srcdst` to
+the `configure` command line to build a version of libjpeg-turbo that lacks the
+`jpeg_mem_src()` and `jpeg_mem_dest()` functions.  These functions were not
+part of the original libjpeg v6b and v7 APIs, so removing them ensures strict
+conformance with those APIs.  See [README.md](README.md) for more information.
+
+
+### Arithmetic Coding Support
+
+Since the patent on arithmetic coding has expired, this functionality has been
+included in this release of libjpeg-turbo.  libjpeg-turbo's implementation is
+based on the implementation in libjpeg v8, but it works when emulating libjpeg
+v7 or v6b as well.  The default is to enable both arithmetic encoding and
+decoding, but those who have philosophical objections to arithmetic coding can
+add `--without-arith-enc` or `--without-arith-dec` to the `configure` command
+line to disable encoding or decoding (respectively.)
+
+
+### TurboJPEG Java Wrapper
+
+Add `--with-java` to the `configure` command line to incorporate an optional
+Java Native Interface wrapper into the TurboJPEG shared library and build the
+Java front-end classes to support it.  This allows the TurboJPEG shared library
+to be used directly from Java applications.  See [java/README](java/README) for
+more details.
+
+You can set the `JAVAC`, `JAR`, and `JAVA` configure variables to specify
+alternate commands for javac, jar, and java (respectively.)  You can also
+set the `JAVACFLAGS` configure variable to specify arguments that should be
+passed to the Java compiler when building the front-end classes, and
+`JNI_CFLAGS` to specify arguments that should be passed to the C compiler when
+building the JNI wrapper.  Run `configure --help` for more details.
+
+
+Installing libjpeg-turbo
+------------------------
+
+If you intend to install these libraries and the associated header files, then
+replace 'make' in the instructions above with
+
+    make install prefix={base dir} libdir={library directory}
+
+For example,
+
+    make install prefix=/usr/local libdir=/usr/local/lib64
+
+will install the header files in /usr/local/include and the library files in
+/usr/local/lib64.  If `prefix` and `libdir` are not specified, then the default
+is to install the header files in /opt/libjpeg-turbo/include and the library
+files in /opt/libjpeg-turbo/lib32 (32-bit) or /opt/libjpeg-turbo/lib64
+(64-bit.)
+
+NOTE: You can specify a prefix of /usr and a libdir of, for instance,
+/usr/lib64 to overwrite the system's version of libjpeg.  If you do this,
+however, then be sure to BACK UP YOUR SYSTEM'S INSTALLATION OF LIBJPEG before
+overwriting it.  It is recommended that you instead install libjpeg-turbo into
+a non-system directory and manipulate the `LD_LIBRARY_PATH` or create symlinks
+to force applications to use libjpeg-turbo instead of libjpeg.  See
+[README.md](README.md) for more information.
+
+
+Build Recipes
+-------------
+
+
+### 32-bit Build on 64-bit Linux
+
+Add
+
+    --host i686-pc-linux-gnu CFLAGS='-O3 -m32' LDFLAGS=-m32
+
+to the `configure` command line.
+
+
+### 64-bit Build on 64-bit OS X
+
+Add
+
+    --host x86_64-apple-darwin NASM=/opt/local/bin/nasm
+
+to the `configure` command line.  NASM 2.07 or later from MacPorts must be
+installed.
+
+
+### 32-bit Build on 64-bit OS X
+
+Add
+
+    --host i686-apple-darwin CFLAGS='-O3 -m32' LDFLAGS=-m32
+
+to the `configure` command line.
+
+
+### 64-bit Backward-Compatible Build on 64-bit OS X
+
+Add
+
+    --host x86_64-apple-darwin NASM=/opt/local/bin/nasm \
+      CFLAGS='-mmacosx-version-min=10.5 -O3' \
+      LDFLAGS='-mmacosx-version-min=10.5'
+
+to the `configure` command line.  NASM 2.07 or later from MacPorts must be
+installed.
+
+
+### 32-bit Backward-Compatible Build on OS X
+
+Add
+
+    --host i686-apple-darwin \
+      CFLAGS='-mmacosx-version-min=10.5 -O3 -m32' \
+      LDFLAGS='-mmacosx-version-min=10.5 -m32'
+
+to the `configure` command line.
+
+
+### 64-bit Build on 64-bit Solaris
+
+Add
+
+    --host x86_64-pc-solaris CFLAGS='-O3 -m64' LDFLAGS=-m64
+
+to the `configure` command line.
+
+
+### 32-bit Build on 64-bit FreeBSD
+
+Add
+
+    --host i386-unknown-freebsd CC='gcc -B /usr/lib32' CFLAGS='-O3 -m32' \
+      LDFLAGS='-B/usr/lib32'
+
+to the `configure` command line.  NASM 2.07 or later from FreeBSD ports must be
+installed.
+
+
+### Oracle Solaris Studio
+
+Add
+
+    CC=cc
+
+to the `configure` command line.  libjpeg-turbo will automatically be built
+with the maximum optimization level (-xO5) unless you override `CFLAGS`.
+
+To build a 64-bit version of libjpeg-turbo using Oracle Solaris Studio, add
+
+    --host x86_64-pc-solaris CC=cc CFLAGS='-xO5 -m64' LDFLAGS=-m64
+
+to the `configure` command line.
+
+
+### MinGW Build on Cygwin
+
+Use CMake (see recipes below)
+
+
+ARM Support
+-----------
+
+This release of libjpeg-turbo can use ARM NEON SIMD instructions to accelerate
+JPEG compression/decompression by approximately 2-4x on ARMv7 and later
+platforms.  If libjpeg-turbo is configured on an ARM Linux platform, then the
+build system will automatically include the NEON SIMD routines, if they are
+supported.  Build instructions for other ARM-based platforms follow.
+
+
+### Building libjpeg-turbo for iOS
+
+iOS platforms, such as the iPhone and iPad, use ARM processors, some of which
+support NEON instructions.  Additional steps are required in order to build
+libjpeg-turbo for these platforms.
+
+
+#### Additional build requirements
+
+- [gas-preprocessor.pl]
+  (https://raw.githubusercontent.com/libjpeg-turbo/gas-preprocessor/master/gas-preprocessor.pl)
+  should be installed in your `PATH`.
+
+
+#### ARM 32-bit Build (Xcode 4.6.x and earlier, LLVM-GCC)
+
+Set the following shell variables for simplicity:
+
+  *Xcode 4.2 and earlier*
+
+    IOS_PLATFORMDIR=/Developer/Platforms/iPhoneOS.platform`
+
+  *Xcode 4.3 and later*
+
+    IOS_PLATFORMDIR=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform
+
+  *All Xcode versions*
+
+    IOS_SYSROOT=$IOS_PLATFORMDIR/Developer/SDKs/iPhoneOS*.sdk
+    IOS_GCC=$IOS_PLATFORMDIR/Developer/usr/bin/arm-apple-darwin10-llvm-gcc-4.2
+
+  *ARMv6 (code will run on all iOS devices, not SIMD-accelerated)*
+  [NOTE: Requires Xcode 4.4.x or earlier]
+
+    IOS_CFLAGS="-march=armv6 -mcpu=arm1176jzf-s -mfpu=vfp"
+
+  *ARMv7 (code will run on iPhone 3GS-4S/iPad 1st-3rd Generation and newer)*
+
+    IOS_CFLAGS="-march=armv7 -mcpu=cortex-a8 -mtune=cortex-a8 -mfpu=neon"
+
+  *ARMv7s (code will run on iPhone 5/iPad 4th Generation and newer)*
+  [NOTE: Requires Xcode 4.5 or later]
+
+    IOS_CFLAGS="-march=armv7s -mcpu=swift -mtune=swift -mfpu=neon"
+
+Follow the procedure under "Building libjpeg-turbo" above, adding
+
+    --host arm-apple-darwin10 \
+      CC="$IOS_GCC" LD="$IOS_GCC" \
+      CFLAGS="-mfloat-abi=softfp -isysroot $IOS_SYSROOT -O3 $IOS_CFLAGS" \
+      LDFLAGS="-mfloat-abi=softfp -isysroot $IOS_SYSROOT $IOS_CFLAGS"
+
+to the `configure` command line.
+
+
+#### ARM 32-bit Build (Xcode 5.0.x and later, Clang)
+
+Set the following shell variables for simplicity:
+
+    IOS_PLATFORMDIR=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform
+    IOS_SYSROOT=$IOS_PLATFORMDIR/Developer/SDKs/iPhoneOS*.sdk
+    IOS_GCC=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
+
+  *ARMv7 (code will run on iPhone 3GS-4S/iPad 1st-3rd Generation and newer)*
+
+    IOS_CFLAGS="-arch armv7"
+
+  *ARMv7s (code will run on iPhone 5/iPad 4th Generation and newer)*
+
+    IOS_CFLAGS="-arch armv7s"
+
+Follow the procedure under "Building libjpeg-turbo" above, adding
+
+    --host arm-apple-darwin10 \
+      CC="$IOS_GCC" LD="$IOS_GCC" \
+      CFLAGS="-mfloat-abi=softfp -isysroot $IOS_SYSROOT -O3 $IOS_CFLAGS" \
+      LDFLAGS="-mfloat-abi=softfp -isysroot $IOS_SYSROOT $IOS_CFLAGS" \
+      CCASFLAGS="-no-integrated-as $IOS_CFLAGS"
+
+to the `configure` command line.
+
+
+#### ARMv8 64-bit Build (Xcode 5.0.x and later, Clang)
+
+Code will run on iPhone 5S/iPad Mini 2/iPad Air and newer.
+
+Set the following shell variables for simplicity:
+
+    IOS_PLATFORMDIR=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform
+    IOS_SYSROOT=$IOS_PLATFORMDIR/Developer/SDKs/iPhoneOS*.sdk
+    IOS_GCC=/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang
+    IOS_CFLAGS="-arch arm64"
+
+Follow the procedure under "Building libjpeg-turbo" above, adding
+
+    --host aarch64-apple-darwin \
+      CC="$IOS_GCC" LD="$IOS_GCC" \
+      CFLAGS="-isysroot $IOS_SYSROOT -O3 $IOS_CFLAGS" \
+      LDFLAGS="-isysroot $IOS_SYSROOT $IOS_CFLAGS"
+
+to the `configure` command line.
+
+
+NOTE:  You can also add `-miphoneos-version-min={version}` to `$IOS_CFLAGS`
+above in order to support older versions of iOS than the default version
+supported by the SDK.
+
+Once built, lipo can be used to combine the ARMv6, v7, v7s, and/or v8 variants
+into a universal library.
+
+
+### Building libjpeg-turbo for Android
+
+Building libjpeg-turbo for Android platforms requires the Android NDK
+(https://developer.android.com/tools/sdk/ndk) and autotools.  The following is
+a general recipe script that can be modified for your specific needs.
+
+    # Set these variables to suit your needs
+    NDK_PATH={full path to the "ndk" directory-- for example, /opt/android/ndk}
+    BUILD_PLATFORM={the platform name for the NDK package you installed--
+      for example, "windows-x86" or "linux-x86_64" or "darwin-x86_64"}
+    TOOLCHAIN_VERSION={"4.8", "4.9", "clang3.5", etc.  This corresponds to a
+      toolchain directory under ${NDK_PATH}/toolchains/.}
+    ANDROID_VERSION={The minimum version of Android to support-- for example,
+      "16", "19", etc.  "21" or later is required for a 64-bit build.}
+
+    # 32-bit ARMv7 build
+    HOST=arm-linux-androideabi
+    SYSROOT=${NDK_PATH}/platforms/android-${ANDROID_VERSION}/arch-arm
+    ANDROID_CFLAGS="-march=armv7-a -mfloat-abi=softfp -fprefetch-loop-arrays \
+      --sysroot=${SYSROOT}"
+
+    # 64-bit ARMv8 build
+    HOST=aarch64-linux-android
+    SYSROOT=${NDK_PATH}/platforms/android-${ANDROID_VERSION}/arch-arm64
+    ANDROID_CFLAGS="--sysroot=${SYSROOT}"
+
+    TOOLCHAIN=${NDK_PATH}/toolchains/${HOST}-${TOOLCHAIN_VERSION}/prebuilt/${BUILD_PLATFORM}
+    ANDROID_INCLUDES="-I${SYSROOT}/usr/include -I${TOOLCHAIN}/include"
+    export CPP=${TOOLCHAIN}/bin/${HOST}-cpp
+    export AR=${TOOLCHAIN}/bin/${HOST}-ar
+    export AS=${TOOLCHAIN}/bin/${HOST}-as
+    export NM=${TOOLCHAIN}/bin/${HOST}-nm
+    export CC=${TOOLCHAIN}/bin/${HOST}-gcc
+    export LD=${TOOLCHAIN}/bin/${HOST}-ld
+    export RANLIB=${TOOLCHAIN}/bin/${HOST}-ranlib
+    export OBJDUMP=${TOOLCHAIN}/bin/${HOST}-objdump
+    export STRIP=${TOOLCHAIN}/bin/${HOST}-strip
+    cd {build_directory}
+    sh {source_directory}/configure --host=${HOST} \
+      CFLAGS="${ANDROID_INCLUDES} ${ANDROID_CFLAGS} -O3 -fPIE" \
+      CPPFLAGS="${ANDROID_INCLUDES} ${ANDROID_CFLAGS}" \
+      LDFLAGS="${ANDROID_CFLAGS} -pie" --with-simd ${1+"$@"}
+    make
+
+If building for Android 4.0.x (API level < 16) or earlier, remove `-fPIE` from
+`CFLAGS` and `-pie` from `LDFLAGS`.
+
+
+Building on Windows (Visual C++ or MinGW)
+=========================================
+
+
+Build Requirements
+------------------
+
+- [CMake](http://www.cmake.org) v2.8.8 or later
+
+- Microsoft Visual C++ 2005 or later
+
+  If you don't already have Visual C++, then the easiest way to get it is by
+  installing the Windows SDK:
+
+  http://msdn.microsoft.com/en-us/windows/bb980924.aspx
+
+  The Windows SDK includes both 32-bit and 64-bit Visual C++ compilers and
+  everything necessary to build libjpeg-turbo.
+
+  * You can also use Microsoft Visual Studio Express Edition, which is a free
+    download.  (NOTE: versions prior to 2012 can only be used to build 32-bit
+    code.)
+  * If you intend to build libjpeg-turbo from the command line, then add the
+    appropriate compiler and SDK directories to the `INCLUDE`, `LIB`, and
+    `PATH` environment variables.  This is generally accomplished by
+    executing `vcvars32.bat` or `vcvars64.bat` and `SetEnv.cmd`.
+    `vcvars32.bat` and `vcvars64.bat` are part of Visual C++ and are located in
+    the same directory as the compiler.  `SetEnv.cmd` is part of the Windows
+    SDK.  You can pass optional arguments to `SetEnv.cmd` to specify a 32-bit
+    or 64-bit build environment.
+
+... OR ...
+
+- MinGW
+
+  MinGW-builds (http://sourceforge.net/projects/mingwbuilds/) or
+  tdm-gcc (http://tdm-gcc.tdragon.net/) recommended if building on a Windows
+  machine.  Both distributions install a Start Menu link that can be used to
+  launch a command prompt with the appropriate compiler paths automatically
+  set.
+
+- [NASM](http://www.nasm.us/) 0.98 or later (NASM 2.05 or later is required for
+  a 64-bit build)
+
+- If building the TurboJPEG Java wrapper, JDK 1.5 or later is required.  This
+  can be downloaded from http://www.java.com.
+
+
+Out-of-Tree Builds
+------------------
+
+Binary objects, libraries, and executables are generated in the same directory
+from which `cmake` was executed (the "binary directory"), and this directory
+need not necessarily be the same as the libjpeg-turbo source directory.  You
+can create multiple independent binary directories, in which different versions
+of libjpeg-turbo can be built from the same source tree using different
+compilers or settings.  In the sections below, *{build_directory}* refers to
+the binary directory, whereas *{source_directory}* refers to the libjpeg-turbo
+source directory.  For in-tree builds, these directories are the same.
+
+
+Building libjpeg-turbo
+----------------------
+
+
+### Visual C++ (Command Line)
+
+    cd {build_directory}
+    cmake -G "NMake Makefiles" -DCMAKE_BUILD_TYPE=Release {source_directory}
+    nmake
+
+This will build either a 32-bit or a 64-bit version of libjpeg-turbo, depending
+on which version of cl.exe is in the `PATH`.
+
+The following files will be generated under *{build_directory}*:
+
+**jpeg-static.lib**
+Static link library for the libjpeg API
+
+**sharedlib/jpeg{version}.dll**
+DLL for the libjpeg API
+
+**sharedlib/jpeg.lib**
+Import library for the libjpeg API
+
+**turbojpeg-static.lib**
+Static link library for the TurboJPEG API
+
+**turbojpeg.dll**
+DLL for the TurboJPEG API
+
+**turbojpeg.lib**
+Import library for the TurboJPEG API
+
+*{version}* is 62, 7, or 8, depending on whether libjpeg v6b (default), v7, or
+v8 emulation is enabled.
+
+
+### Visual C++ (IDE)
+
+Choose the appropriate CMake generator option for your version of Visual Studio
+(run `cmake` with no arguments for a list of available generators.)  For
+instance:
+
+    cd {build_directory}
+    cmake -G "Visual Studio 10" {source_directory}
+
+NOTE:  Add "Win64" to the generator name (for example, "Visual Studio 10
+Win64") to build a 64-bit version of libjpeg-turbo.  Recent versions of CMake
+no longer document that.  A separate build directory must be used for 32-bit
+and 64-bit builds.
+
+You can then open ALL_BUILD.vcproj in Visual Studio and build one of the
+configurations in that project ("Debug", "Release", etc.) to generate a full
+build of libjpeg-turbo.
+
+This will generate the following files under *{build_directory}*:
+
+**{configuration}/jpeg-static.lib**
+Static link library for the libjpeg API
+
+**sharedlib/{configuration}/jpeg{version}.dll**
+DLL for the libjpeg API
+
+**sharedlib/{configuration}/jpeg.lib**
+Import library for the libjpeg API
+
+**{configuration}/turbojpeg-static.lib**
+Static link library for the TurboJPEG API
+
+**{configuration}/turbojpeg.dll**
+DLL for the TurboJPEG API
+
+**{configuration}/turbojpeg.lib**
+Import library for the TurboJPEG API
+
+*{configuration}* is Debug, Release, RelWithDebInfo, or MinSizeRel, depending
+on the configuration you built in the IDE, and *{version}* is 62, 7, or 8,
+depending on whether libjpeg v6b (default), v7, or v8 emulation is enabled.
+
+
+### MinGW
+
+NOTE: This assumes that you are building on a Windows machine.  If you are
+cross-compiling on a Linux/Unix machine, then see "Build Recipes" below.
+
+    cd {build_directory}
+    cmake -G "MinGW Makefiles" {source_directory}
+    mingw32-make
+
+This will generate the following files under *{build_directory}*:
+
+**libjpeg.a**
+Static link library for the libjpeg API
+
+**sharedlib/libjpeg-{version}.dll**
+DLL for the libjpeg API
+
+**sharedlib/libjpeg.dll.a**
+Import library for the libjpeg API
+
+**libturbojpeg.a**
+Static link library for the TurboJPEG API
+
+**libturbojpeg.dll**
+DLL for the TurboJPEG API
+
+**libturbojpeg.dll.a**
+Import library for the TurboJPEG API
+
+*{version}* is 62, 7, or 8, depending on whether libjpeg v6b (default), v7, or
+v8 emulation is enabled.
+
+
+### Debug Build
+
+Add `-DCMAKE_BUILD_TYPE=Debug` to the `cmake` command line.  Or, if building
+with NMake, remove `-DCMAKE_BUILD_TYPE=Release` (Debug builds are the default
+with NMake.)
+
+
+### libjpeg v7 or v8 API/ABI Emulation
+
+Add `-DWITH_JPEG7=1` to the `cmake` command line to build a version of
+libjpeg-turbo that is API/ABI-compatible with libjpeg v7.  Add `-DWITH_JPEG8=1`
+to the `cmake` command line to build a version of libjpeg-turbo that is
+API/ABI-compatible with libjpeg v8.  See [README.md](README.md) for more
+information on libjpeg v7 and v8 emulation.
+
+
+### In-Memory Source/Destination Managers
+
+When using libjpeg v6b or v7 API/ABI emulation, add `-DWITH_MEM_SRCDST=0` to
+the `cmake` command line to build a version of libjpeg-turbo that lacks the
+`jpeg_mem_src()` and `jpeg_mem_dest()` functions.  These functions were not
+part of the original libjpeg v6b and v7 APIs, so removing them ensures strict
+conformance with those APIs.  See [README.md](README.md) for more information.
+
+
+### Arithmetic Coding Support
+
+Since the patent on arithmetic coding has expired, this functionality has been
+included in this release of libjpeg-turbo.  libjpeg-turbo's implementation is
+based on the implementation in libjpeg v8, but it works when emulating libjpeg
+v7 or v6b as well.  The default is to enable both arithmetic encoding and
+decoding, but those who have philosophical objections to arithmetic coding can
+add `-DWITH_ARITH_ENC=0` or `-DWITH_ARITH_DEC=0` to the `cmake` command line to
+disable encoding or decoding (respectively.)
+
+
+### TurboJPEG Java Wrapper
+
+Add `-DWITH_JAVA=1` to the `cmake` command line to incorporate an optional Java
+Native Interface wrapper into the TurboJPEG shared library and build the Java
+front-end classes to support it.  This allows the TurboJPEG shared library to
+be used directly from Java applications.  See [java/README](java/README) for
+more details.
+
+If you are using CMake 2.8, you can set the `Java_JAVAC_EXECUTABLE`,
+`Java_JAVA_EXECUTABLE`, and `Java_JAR_EXECUTABLE` CMake variables to specify
+alternate commands or locations for javac, jar, and java (respectively.)  You
+can also set the `JAVACFLAGS` CMake variable to specify arguments that should
+be passed to the Java compiler when building the front-end classes.
+
+
+Installing libjpeg-turbo
+------------------------
+
+You can use the build system to install libjpeg-turbo into a directory of your
+choosing (as opposed to creating an installer.)  To do this, add:
+
+    -DCMAKE_INSTALL_PREFIX={install_directory}
+
+to the cmake command line.
+
+For example,
+
+    cmake -G "NMake Makefiles" -DCMAKE_BUILD_TYPE=Release \
+      -DCMAKE_INSTALL_PREFIX=c:\libjpeg-turbo {source_directory}
+    nmake install
+
+will install the header files in c:\libjpeg-turbo\include, the library files
+in c:\libjpeg-turbo\lib, the DLL's in c:\libjpeg-turbo\bin, and the
+documentation in c:\libjpeg-turbo\doc.
+
+
+Build Recipes
+-------------
+
+
+### 64-bit MinGW Build on Cygwin
+
+    cd {build_directory}
+    CC=/usr/bin/x86_64-w64-mingw32-gcc \
+      cmake -G "Unix Makefiles" -DCMAKE_SYSTEM_NAME=Windows \
+      -DCMAKE_RC_COMPILER=/usr/bin/x86_64-w64-mingw32-windres.exe \
+      {source_directory}
+    make
+
+This produces a 64-bit build of libjpeg-turbo that does not depend on
+cygwin1.dll or other Cygwin DLL's.  The mingw64-x86\_64-gcc-core and
+mingw64-x86\_64-gcc-g++ packages (and their dependencies) must be installed.
+
+
+### 32-bit MinGW Build on Cygwin
+
+     cd {build_directory}
+     CC=/usr/bin/i686-w64-mingw32-gcc \
+       cmake -G "Unix Makefiles" -DCMAKE_SYSTEM_NAME=Windows \
+       -DCMAKE_RC_COMPILER=/usr/bin/i686-w64-mingw32-windres.exe \
+       {source_directory}
+     make
+
+This produces a 32-bit build of libjpeg-turbo that does not depend on
+cygwin1.dll or other Cygwin DLL's.  The mingw64-i686-gcc-core and
+mingw64-i686-gcc-g++ packages (and their dependencies) must be installed.
+
+
+### MinGW Build on Linux
+
+    cd {build_directory}
+    CC={mingw_binary_path}/i686-pc-mingw32-gcc \
+      cmake -G "Unix Makefiles" -DCMAKE_SYSTEM_NAME=Windows \
+      -DCMAKE_RC_COMPILER={mingw_binary_path}/i686-pc-mingw32-windres \
+      -DCMAKE_AR={mingw_binary_path}/i686-pc-mingw32-ar \
+      -DCMAKE_RANLIB={mingw_binary_path}/i686-pc-mingw32-ranlib \
+      {source_directory}
+    make
+
+
+Creating Release Packages
+=========================
+
+The following commands can be used to create various types of release packages:
+
+
+Unix/Linux
+----------
+
+    make rpm
+
+Create Red Hat-style binary RPM package.  Requires RPM v4 or later.
+
+    make srpm
+
+This runs `make dist` to create a pristine source tarball, then creates a
+Red Hat-style source RPM package from the tarball.  Requires RPM v4 or later.
+
+    make deb
+
+Create Debian-style binary package.  Requires dpkg.
+
+    make dmg
+
+Create Macintosh package/disk image.  This requires pkgbuild and
+productbuild, which are installed by default on OS X 10.7 and later and which
+can be obtained by installing Xcode 3.2.6 (with the "Unix Development"
+option) on OS X 10.6.  Packages built in this manner can be installed on OS X
+10.5 and later, but they must be built on OS X 10.6 or later.
+
+    make udmg [BUILDDIR32={32-bit build directory}]
+
+On 64-bit OS X systems, this creates a Macintosh package and disk image that
+contains universal i386/x86-64 binaries.  You should first configure a 32-bit
+out-of-tree build of libjpeg-turbo, then configure a 64-bit out-of-tree
+build, then run `make udmg` from the 64-bit build directory.  The build
+system will look for the 32-bit build under *{source_directory}*/osxx86 by
+default, but you can override this by setting the `BUILDDIR32` variable on the
+make command line as shown above.
+
+    make iosdmg [BUILDDIR32={32-bit build directory}] \
+      [BUILDDIRARMV6={ARMv6 build directory}] \
+      [BUILDDIRARMV7={ARMv7 build directory}] \
+      [BUILDDIRARMV7S={ARMv7s build directory}] \
+      [BUILDDIRARMV8={ARMv8 build directory}]
+
+On OS X systems, this creates a Macintosh package and disk image in which the
+libjpeg-turbo static libraries contain ARM architectures necessary to build
+iOS applications.  If building on an x86-64 system, the binaries will also
+contain the i386 architecture, as with `make udmg` above.  You should first
+configure ARMv6, ARMv7, ARMv7s, and/or ARMv8 out-of-tree builds of
+libjpeg-turbo (see "Building libjpeg-turbo for iOS" above.)  If you are
+building an x86-64 version of libjpeg-turbo, you should configure a 32-bit
+out-of-tree build as well.  Next, build libjpeg-turbo as you would normally,
+using an out-of-tree build.  When it is built, run `make iosdmg` from the
+build directory.  The build system will look for the ARMv6 build under
+*{source_directory}*/iosarmv6 by default, the ARMv7 build under
+*{source_directory}*/iosarmv7 by default, the ARMv7s build under
+*{source_directory}*/iosarmv7s by default, the ARMv8 build under
+*{source_directory}*/iosarmv8 by default, and (if applicable) the 32-bit build
+under *{source_directory}*/osxx86 by default, but you can override this by
+setting the `BUILDDIR32`, `BUILDDIRARMV6`, `BUILDDIRARMV7`, `BUILDDIRARMV7S`,
+and/or `BUILDDIRARMV8` variables on the `make` command line as shown above.
+
+NOTE: If including an ARMv8 build in the package, then you may need to use
+Xcode's version of lipo instead of the operating system's.  To do this, pass
+an argument of `LIPO="xcrun lipo"` on the make command line.
+
+    make cygwinpkg
+
+Build a Cygwin binary package.
+
+
+Windows
+-------
+
+If using NMake:
+
+    cd {build_directory}
+    nmake installer
+
+If using MinGW:
+
+    cd {build_directory}
+    make installer
+
+If using the Visual Studio IDE, build the "installer" project.
+
+The installer package (libjpeg-turbo[-gcc][64].exe) will be located under
+*{build_directory}*.  If building using the Visual Studio IDE, then the
+installer package will be located in a subdirectory with the same name as the
+configuration you built (such as *{build_directory}*\Debug\ or
+*{build_directory}*\Release\).
+
+Building a Windows installer requires the Nullsoft Install System
+(http://nsis.sourceforge.net/.)  makensis.exe should be in your `PATH`.
+
+
+Regression testing
+==================
+
+The most common way to test libjpeg-turbo is by invoking `make test` on
+Unix/Linux platforms or `ctest` on Windows platforms, once the build has
+completed.  This runs a series of tests to ensure that mathematical
+compatibility has been maintained between libjpeg-turbo and libjpeg v6b.  This
+also invokes the TurboJPEG unit tests, which ensure that the colorspace
+extensions, YUV encoding, decompression scaling, and other features of the
+TurboJPEG C and Java APIs are working properly (and, by extension, that the
+equivalent features of the underlying libjpeg API are also working.)
+
+Invoking `make testclean` or `nmake testclean` (if using NMake) or building
+the 'testclean' target (if using the Visual Studio IDE) will clean up the
+output images generated by `make test`.
+
+On Unix/Linux platforms, more extensive tests of the TurboJPEG C and Java
+wrappers can be run by invoking `make tjtest`.  These extended TurboJPEG tests
+essentially iterate through all of the available features of the TurboJPEG APIs
+that are not covered by the TurboJPEG unit tests (this includes the lossless
+transform options) and compare the images generated by each feature to images
+generated using the equivalent feature in the libjpeg API.  The extended
+TurboJPEG tests are meant to test for regressions in the TurboJPEG wrappers,
+not in the underlying libjpeg API library.