adding ffmpeg specific version

1 files changed, 50 insertions, 0 deletions

diff --git a/ffmpeg1/doc/build_system.txt b/ffmpeg1/doc/build_system.txt
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+FFmpeg currently uses a custom build system, this text attempts to document
+some of its obscure features and options.
+
+Makefile variables:
+
+V
+    Disable the default terse mode, the full command issued by make and its
+    output will be shown on the screen.
+
+DESTDIR
+    Destination directory for the install targets, useful to prepare packages
+    or install FFmpeg in cross-environments.
+
+Makefile targets:
+
+all
+    Default target, builds all the libraries and the executables.
+
+fate
+    Run the fate test suite, note you must have installed it
+
+fate-list
+    Will list all fate/regression test targets
+
+install
+    Install headers, libraries and programs.
+
+libavformat/output-example
+    Build the libavformat basic example.
+
+libavcodec/api-example
+    Build the libavcodec basic example.
+
+libswscale/swscale-test
+    Build the swscale self-test (useful also as example).
+
+
+Useful standard make commands:
+make -t <target>
+    Touch all files that otherwise would be build, this is useful to reduce
+    unneeded rebuilding when changing headers, but note you must force rebuilds
+    of files that actually need it by hand then.
+
+make -j<num>
+    rebuild with multiple jobs at the same time. Faster on multi processor systems
+
+make -k
+    continue build in case of errors, this is useful for the regression tests
+    sometimes but note it will still not run all reg tests.
+