void(* horiz_filter_clip)(int16_t *output, const int16_t *low, const int16_t *high, int width, int bpc)
void(* vert_filter)(int16_t *output, ptrdiff_t out_stride, const int16_t *low, ptrdiff_t low_stride, const int16_t *high, ptrdiff_t high_stride, int width, int height)
void(* horiz_filter)(int16_t *output, ptrdiff_t out_stride, const int16_t *low, ptrdiff_t low_stride, const int16_t *high, ptrdiff_t high_stride, int width, int height)