FILTER_BW_O4_1    231 libavcodec/iirfilter.c         FILTER_BW_O4_1(0, 1, 2, 3, fmt);    \
FILTER_BW_O4_1    232 libavcodec/iirfilter.c         FILTER_BW_O4_1(1, 2, 3, 0, fmt);    \
FILTER_BW_O4_1    233 libavcodec/iirfilter.c         FILTER_BW_O4_1(2, 3, 0, 1, fmt);    \
FILTER_BW_O4_1    234 libavcodec/iirfilter.c         FILTER_BW_O4_1(3, 0, 1, 2, fmt);    \