README - 9 January 2017 Welcome to the WebM VP8/VP9 Codec SDK! COMPILING THE APPLICATIONS/LIBRARIES:  The build system used is similar to autotools. Building generally consists of  "configuring" with your desired build options, then using GNU make to build  the application.   1. Prerequisites     * All x86 targets require the Yasm[1] assembler be installed.    * All Windows builds require that Cygwin[2] be installed.    * Building the documentation requires Doxygen[3]. If you do not      have this package, the install-docs option will be disabled.    * Downloading the data for the unit tests requires curl[4] and sha1sum.      sha1sum is provided via the GNU coreutils, installed by default on      many *nix platforms, as well as MinGW and Cygwin. If coreutils is not      available, a compatible version of sha1sum can be built from      source[5]. These requirements are optional if not running the unit      tests.     [1]: http://www.tortall.net/projects/yasm    [2]: http://www.cygwin.com    [3]: http://www.doxygen.org    [4]: http://curl.haxx.se    [5]: http://www.microbrew.org/tools/md5sha1sum/   2. Out-of-tree builds  Out of tree builds are a supported method of building the application. For  an out of tree build, the source tree is kept separate from the object  files produced during compilation. For instance:     $ mkdir build    $ cd build    $ ../libvpx/configure <options>    $ make   3. Configuration options  The 'configure' script supports a number of options. The --help option can be  used to get a list of supported options:    $ ../libvpx/configure --help   4. Cross development  For cross development, the most notable option is the --target option. The  most up-to-date list of supported targets can be found at the bottom of the  --help output of the configure script. As of this writing, the list of  available targets is:     arm64-android-gcc    arm64-darwin-gcc    arm64-linux-gcc    armv7-android-gcc    armv7-darwin-gcc    armv7-linux-rvct    armv7-linux-gcc    armv7-none-rvct    armv7-win32-vs11    armv7-win32-vs12    armv7-win32-vs14    armv7s-darwin-gcc    armv8-linux-gcc    mips32-linux-gcc    mips64-linux-gcc    sparc-solaris-gcc    x86-android-gcc    x86-darwin8-gcc    x86-darwin8-icc    x86-darwin9-gcc    x86-darwin9-icc    x86-darwin10-gcc    x86-darwin11-gcc    x86-darwin12-gcc    x86-darwin13-gcc    x86-darwin14-gcc    x86-darwin15-gcc    x86-iphonesimulator-gcc    x86-linux-gcc    x86-linux-icc    x86-os2-gcc    x86-solaris-gcc    x86-win32-gcc    x86-win32-vs10    x86-win32-vs11    x86-win32-vs12    x86-win32-vs14    x86_64-android-gcc    x86_64-darwin9-gcc    x86_64-darwin10-gcc    x86_64-darwin11-gcc    x86_64-darwin12-gcc    x86_64-darwin13-gcc    x86_64-darwin14-gcc    x86_64-darwin15-gcc    x86_64-iphonesimulator-gcc    x86_64-linux-gcc    x86_64-linux-icc    x86_64-solaris-gcc    x86_64-win64-gcc    x86_64-win64-vs10    x86_64-win64-vs11    x86_64-win64-vs12    x86_64-win64-vs14    generic-gnu   The generic-gnu target, in conjunction with the CROSS environment variable,  can be used to cross compile architectures that aren't explicitly listed, if  the toolchain is a cross GNU (gcc/binutils) toolchain. Other POSIX toolchains  will likely work as well. For instance, to build using the mipsel-linux-uclibc  toolchain, the following command could be used (note, POSIX SH syntax, adapt  to your shell as necessary):     $ CROSS=mipsel-linux-uclibc- ../libvpx/configure   In addition, the executables to be invoked can be overridden by specifying the  environment variables: CC, AR, LD, AS, STRIP, NM. Additional flags can be  passed to these executables with CFLAGS, LDFLAGS, and ASFLAGS.   5. Configuration errors  If the configuration step fails, the first step is to look in the error log.  This defaults to config.log. This should give a good indication of what went  wrong. If not, contact us for support. VP8/VP9 TEST VECTORS:  The test vectors can be downloaded and verified using the build system after  running configure. To specify an alternate directory the  LIBVPX_TEST_DATA_PATH environment variable can be used.   $ ./configure --enable-unit-tests  $ LIBVPX_TEST_DATA_PATH=../libvpx-test-data make testdata CODE STYLE:  The coding style used by this project is enforced with clang-format using the  configuration contained in the .clang-format file in the root of the  repository.   Before pushing changes for review you can format your code with:  # Apply clang-format to modified .c, .h and .cc files  $ clang-format -i --style=file \    $(git diff --name-only --diff-filter=ACMR '*.[hc]' '*.cc')   Check the .clang-format file for the version used to generate it if there is  any difference between your local formatting and the review system.   See also: http://clang.llvm.org/docs/ClangFormat.html SUPPORT  This library is an open source project supported by its community. Please  email webm-discuss@webmproject.org for help.