How to add a new filter to FFMPEG in c with third-party dependences

I'm a newbie to FFMPEG development and want to add a customized filter to FFMPEG.

I've followed the filter tutorial in the docs. However, it's just a very simplified example and not mentioned how to add other dependences to Makefile. Especially in libavfilter/Makefile, there is only a OBJS-(CONFIG_NAME_FILTER) += name.o for me to add my filter.

I want to add a new video filter with third party dependencies, like third-party c code with some other dependences, third-party compiled .so on Linux, .dylib on Mac, .dll and .lib on Windows, etc.

How can I add these third-party dependences to build process of FFMPEG?