std::unique_ptr<Mux> stream_mux; // To HTTP.
std::unique_ptr<AudioEncoder> stream_audio_encoder;
std::unique_ptr<X264Encoder> x264_encoder; // nullptr if not using x264.
std::unique_ptr<Mux> stream_mux; // To HTTP.
std::unique_ptr<AudioEncoder> stream_audio_encoder;
std::unique_ptr<X264Encoder> x264_encoder; // nullptr if not using x264.