ff_inlink_check_available_frame 1481 libavfilter/avfilter.c     if (!ff_inlink_check_available_frame(link))
ff_inlink_check_available_frame   73 libavfilter/filters.h int ff_inlink_check_available_frame(AVFilterLink *link);
ff_inlink_check_available_frame  290 libavfilter/vf_fps.c         while (s->frames_count < 2 && ff_inlink_check_available_frame(inlink)) {