av_opt_set_q      106 doc/examples/filter_audio.c     av_opt_set_q  (abuffer_ctx, "time_base",      (AVRational){ 1, INPUT_SAMPLERATE },  AV_OPT_SEARCH_CHILDREN);
av_opt_set_q      724 libavutil/opt.h int av_opt_set_q       (void *obj, const char *name, AVRational  val, int search_flags);