blend_slice_yuva420_pm  881 libavfilter/vf_overlay.c         s->blend_slice = s->main_has_alpha ? blend_slice_yuva420_pm : blend_slice_yuv420_pm;
blend_slice_yuva420_pm  898 libavfilter/vf_overlay.c             s->blend_slice = blend_slice_yuva420_pm;