License

FFmpegKit library alone is licensed under the LGPL v3.0.

FFmpegKit bundles (.aar archives, frameworks, xcframeworks), which include both FFmpegKit and FFmpeglibraries, are also licensed under the LGPL v3.0. However, if the source code is built using the optional --enable-gpl flag or prebuilt binaries with -gpl postfix are used, then FFmpegKit bundles become subject to the GPL v3.0. Because, FFmpeg is licensed under the GPL v3.0 in those bundles. And that makes the whole bundle effectively subject to the GPL v3.0.

FFmpegKit build scripts always configure FFmpeg with --enable-version3 option. And never enable non-free libraries. Thus, FFmpeg libraries created by FFmpegKit are licensed under the LGPL v3.0 by default. Only when --enable-gpl is provided they become subject to GPL v3.0. That is how prebuilt binaries with -gpl postfix are compiled.

Refer to Summary to see the licenses of all libraries.