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. DBG Preprocess x86 external assembler files to a .dbg.asm file in the object directory, which then gets compiled. Helps in developing those assembler files. DESTDIR Destination directory for the install targets, useful to prepare packages or install FFmpeg in cross-environments. GEN Set to ‘1’ to generate the missing or mismatched references. Makefile targets: all Default target, builds all the libraries and the executables. fate Run the fate test suite, note that you must have installed it. fate-list List all fate/regression test targets. install Install headers, libraries and programs. examples Build all examples located in doc/examples. libavformat/output-example Build the libavformat basic example. libswscale/swscale-test Build the swscale self-test (useful also as an example). config Reconfigure the project with the current configuration. tools/target_dec_<decoder>_fuzzer Build fuzzer to fuzz the specified decoder. Useful standard make commands: make -t <target> Touch all files that otherwise would be built, this is useful to reduce unneeded rebuilding when changing headers, but note that 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 that it will still not run all reg tests.