INTERP 200 libavfilter/vf_fade.c p[r_idx] = INTERP(r_idx, 0); INTERP 201 libavfilter/vf_fade.c p[g_idx] = INTERP(g_idx, 1); INTERP 202 libavfilter/vf_fade.c p[b_idx] = INTERP(b_idx, 2); INTERP 204 libavfilter/vf_fade.c p[a_idx] = INTERP(a_idx, 3);