BD                265 libavfilter/vf_curves.c         matrix[i][BD] = h[i-1];
BD                272 libavfilter/vf_curves.c         double den = matrix[i][MD] - matrix[i][BD] * matrix[i-1][AD];
BD                275 libavfilter/vf_curves.c         r[i] = (r[i] - matrix[i][BD] * r[i - 1]) * k;