void(* update_sono)(AVFrame *sono, const ColorFloat *c, int idx)
void(* draw_axis)(AVFrame *out, AVFrame *axis, const ColorFloat *c, int off)
void(* draw_bar)(AVFrame *out, const float *h, const float *rcp_h, const ColorFloat *c, int bar_h, float bar_t)
void(* cqt_calc)(FFTComplex *dst, const FFTComplex *src, const Coeffs *coeffs, int len, int fft_len)
void(* permute_coeffs)(float *v, int len)
void(* draw_sono)(AVFrame *out, AVFrame *sono, int off, int idx)
enum AVPixelFormat format