FFmpeg itself is composed of several subcomponents that can be used individually, and outside of FFmpeg. These are

• libavformat which contains muxer information and capabilities.
• libavcodec which contains all the (built-in) video encoding and decoding codecs that FFmpeg contains.
• libswscale contains the (raw pixel) format conversions, and also high speed/assembly optimized versions of certain scaling routines.
• libavfilter contains the filters FFmpeg contains, like adjusting audio sample rate, etc.* libavutil unknown
• libavdevice contains interfaces for working with "local devices" for instance webcams in windows, line-in audio in linux, etc.