FFI bindings for FFmpeg inner libraries.
Linux environment.
Run cargo build to build the bindings. There are three ways for developer to provide FFmpeg libraries for this crate to generate bindings:
If you have a pre-built ffmpeg, set PKG_CONFIG_PATH to the path which points to *.pc files in the build result(e.g. PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" cargo build) then it will use the pre-built FFmpeg libraries.
If no PKG_CONFIG_PATH is set, it will first check if there are libav*-dev installed. If the libraries exists, this crate will use them. If not, it will git clone the FFmpeg from https://github.com/ffmpeg/ffmpeg and then configure and compile it for you.
After the FFmpeg libraries is ready, the build script will take advantage of the package-config(*.pc) files to:
1. Probe paths of the header files for binding generation and generate the binding.
2. Probe library dependencies as project dependencies to ensure this project can be built successfully.
You can use cargo test to test the generated bindings. If you haven't run cargo build and you have pre-built FFmpeg libraries. Set the PKG_CONFIG_PATH like this: PKG_CONFIG_PATH="$HOME/ffmpeg_build/lib/pkgconfig" cargo test which doesn't need to build the FFmpeg separately.
To see it works, you can run cargo run --example slice.