1 README - 24 January 2018
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[2].
13 * All Windows builds require that Cygwin[3] be installed.
14 * Building the documentation requires Doxygen[4]. 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[5] 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[6]. These requirements are optional if not running the unit
23 [1]: http://www.tortall.net/projects/yasm
24 [2]: For Visual Studio the base yasm binary (not vsyasm) should be in the
25 PATH for Visual Studio. For VS2017 it is sufficient to rename
26 yasm-<version>-<arch>.exe to yasm.exe and place it in:
27 Program Files (x86)/Microsoft Visual Studio/2017/<level>/Common7/Tools/
28 [3]: http://www.cygwin.com
29 [4]: http://www.doxygen.org
30 [5]: http://curl.haxx.se
31 [6]: http://www.microbrew.org/tools/md5sha1sum/
34 Out of tree builds are a supported method of building the application. For
35 an out of tree build, the source tree is kept separate from the object
36 files produced during compilation. For instance:
40 $ ../libvpx/configure <options>
43 3. Configuration options
44 The 'configure' script supports a number of options. The --help option can be
45 used to get a list of supported options:
46 $ ../libvpx/configure --help
49 For cross development, the most notable option is the --target option. The
50 most up-to-date list of supported targets can be found at the bottom of the
51 --help output of the configure script. As of this writing, the list of
85 x86-iphonesimulator-gcc
105 x86_64-iphonesimulator-gcc
117 The generic-gnu target, in conjunction with the CROSS environment variable,
118 can be used to cross compile architectures that aren't explicitly listed, if
119 the toolchain is a cross GNU (gcc/binutils) toolchain. Other POSIX toolchains
120 will likely work as well. For instance, to build using the mipsel-linux-uclibc
121 toolchain, the following command could be used (note, POSIX SH syntax, adapt
122 to your shell as necessary):
124 $ CROSS=mipsel-linux-uclibc- ../libvpx/configure
126 In addition, the executables to be invoked can be overridden by specifying the
127 environment variables: CC, AR, LD, AS, STRIP, NM. Additional flags can be
128 passed to these executables with CFLAGS, LDFLAGS, and ASFLAGS.
130 5. Configuration errors
131 If the configuration step fails, the first step is to look in the error log.
132 This defaults to config.log. This should give a good indication of what went
133 wrong. If not, contact us for support.
135 VP8/VP9 TEST VECTORS:
136 The test vectors can be downloaded and verified using the build system after
137 running configure. To specify an alternate directory the
138 LIBVPX_TEST_DATA_PATH environment variable can be used.
140 $ ./configure --enable-unit-tests
141 $ LIBVPX_TEST_DATA_PATH=../libvpx-test-data make testdata
144 The coding style used by this project is enforced with clang-format using the
145 configuration contained in the .clang-format file in the root of the
148 Before pushing changes for review you can format your code with:
149 # Apply clang-format to modified .c, .h and .cc files
150 $ clang-format -i --style=file \
151 $(git diff --name-only --diff-filter=ACMR '*.[hc]' '*.cc')
153 Check the .clang-format file for the version used to generate it if there is
154 any difference between your local formatting and the review system.
156 See also: http://clang.llvm.org/docs/ClangFormat.html
159 This library is an open source project supported by its community. Please
160 email webm-discuss@webmproject.org for help.