Xav requires FFmpeg development packages to be installed on your system. You can install them with one of the following one-liners.
On some platforms, we use pkg-config to determine ffmpeg's include and lib directories.
Fedora
dnf install pkg-config ffmpeg-devel ffmpeg-libsUbuntu
apt install libavcodec-dev libavformat-dev libavutil-dev libswscale-dev libavdevice-devMacOS x86_64
brew install ffmpegMacOS arm64
brew install pkg-config ffmpegWindows
Windows is not supported but PRs are welcomed.