std::function<void(std::shared_ptr<Frame>)> display_decoded_func; // Same, except for INTERPOLATED and FADED_INTERPOLATED.
std::string subtitle; // Blank for none.
std::function<void(std::shared_ptr<Frame>)> display_decoded_func; // Same, except for INTERPOLATED and FADED_INTERPOLATED.
std::string subtitle; // Blank for none.