celt_pitch_xcorr  634 libavfilter/af_arnndn.c     celt_pitch_xcorr(xptr, xptr, ac, fastN, lag+1);
celt_pitch_xcorr  956 libavfilter/af_arnndn.c     celt_pitch_xcorr(x_lp4, y_lp4, xcorr, len>>2, max_pitch>>2);