av_sub_q          140 libavformat/mxf.c     AVRational diff = av_sub_q(time_base, mxf_time_base[idx]);
av_sub_q          168 libavutil/rational.c                     r = av_sub_q(av_add_q(b,a), b);
av_sub_q          126 libavutil/rational.h AVRational av_sub_q(AVRational b, AVRational c) av_const;