1 README - 26 January 2017
3 Welcome to the WebM VP8/VP9 Codec SDK!
5 COMPILING THE APPLICATIONS/LIBRARIES:
6 The build system used is similar to autotools. Building generally consists of
7 "configuring" with your desired build options, then using GNU make to build
12 * All x86 targets require the Yasm[1] assembler be installed.
13 * All Windows builds require that Cygwin[2] be installed.
14 * Building the documentation requires Doxygen[3]. If you do not
15 have this package, the install-docs option will be disabled.
16 * Downloading the data for the unit tests requires curl[4] and sha1sum.
17 sha1sum is provided via the GNU coreutils, installed by default on
18 many *nix platforms, as well as MinGW and Cygwin. If coreutils is not
19 available, a compatible version of sha1sum can be built from
20 source[5]. These requirements are optional if not running the unit
23 [1]: http://www.tortall.net/projects/yasm
24 [2]: http://www.cygwin.com
25 [3]: http://www.doxygen.org
26 [4]: http://curl.haxx.se
27 [5]: http://www.microbrew.org/tools/md5sha1sum/
30 Out of tree builds are a supported method of building the application. For
31 an out of tree build, the source tree is kept separate from the object
32 files produced during compilation. For instance:
36 $ ../libvpx/configure <options>
39 3. Configuration options
40 The 'configure' script supports a number of options. The --help option can be
41 used to get a list of supported options:
42 $ ../libvpx/configure --help
45 For cross development, the most notable option is the --target option. The
46 most up-to-date list of supported targets can be found at the bottom of the
47 --help output of the configure script. As of this writing, the list of
78 x86-iphonesimulator-gcc
97 x86_64-iphonesimulator-gcc
108 The generic-gnu target, in conjunction with the CROSS environment variable,
109 can be used to cross compile architectures that aren't explicitly listed, if
110 the toolchain is a cross GNU (gcc/binutils) toolchain. Other POSIX toolchains
111 will likely work as well. For instance, to build using the mipsel-linux-uclibc
112 toolchain, the following command could be used (note, POSIX SH syntax, adapt
113 to your shell as necessary):
115 $ CROSS=mipsel-linux-uclibc- ../libvpx/configure
117 In addition, the executables to be invoked can be overridden by specifying the
118 environment variables: CC, AR, LD, AS, STRIP, NM. Additional flags can be
119 passed to these executables with CFLAGS, LDFLAGS, and ASFLAGS.
121 5. Configuration errors
122 If the configuration step fails, the first step is to look in the error log.
123 This defaults to config.log. This should give a good indication of what went
124 wrong. If not, contact us for support.
126 VP8/VP9 TEST VECTORS:
127 The test vectors can be downloaded and verified using the build system after
128 running configure. To specify an alternate directory the
129 LIBVPX_TEST_DATA_PATH environment variable can be used.
131 $ ./configure --enable-unit-tests
132 $ LIBVPX_TEST_DATA_PATH=../libvpx-test-data make testdata
135 The coding style used by this project is enforced with clang-format using the
136 configuration contained in the .clang-format file in the root of the
139 Before pushing changes for review you can format your code with:
140 # Apply clang-format to modified .c, .h and .cc files
141 $ clang-format -i --style=file \
142 $(git diff --name-only --diff-filter=ACMR '*.[hc]' '*.cc')
144 Check the .clang-format file for the version used to generate it if there is
145 any difference between your local formatting and the review system.
147 See also: http://clang.llvm.org/docs/ClangFormat.html
150 This library is an open source project supported by its community. Please
151 email webm-discuss@webmproject.org for help.