upmix_2_1         121 libavfilter/af_surround.c     void (*upmix_2_1)(AVFilterContext *ctx,
upmix_2_1        1196 libavfilter/af_surround.c         s->upmix_2_1(ctx, l_phase, r_phase, c_phase, mag_total, lfe_re, lfe_im, x, y, n);
upmix_2_1        1410 libavfilter/af_surround.c             s->upmix_stereo = upmix_2_1;
upmix_2_1        1450 libavfilter/af_surround.c             s->upmix_2_1 = upmix_5_1_back_2_1;