CHROMA_FUNC      1731 libavfilter/vf_waveform.c CHROMA_FUNC(column,        1, 0)
CHROMA_FUNC      1732 libavfilter/vf_waveform.c CHROMA_FUNC(row_mirror,    0, 1)
CHROMA_FUNC      1733 libavfilter/vf_waveform.c CHROMA_FUNC(row,           0, 0)