diff --git a/libmpcodecs/vd.c b/libmpcodecs/vd.c
index f56d89296e..3ca8b5ce01 100644
--- a/libmpcodecs/vd.c
+++ b/libmpcodecs/vd.c
@@ -108,6 +108,7 @@ int opt_screen_size_y=0;
 int screen_size_xy=0;
 float movie_aspect=-1.0;
 int vo_flags=0;
+int vd_use_slices=1;
 
 static vo_tune_info_t vtune;
 
diff --git a/libmpcodecs/vd.h b/libmpcodecs/vd.h
index 4caff730be..05da2ed4bf 100644
--- a/libmpcodecs/vd.h
+++ b/libmpcodecs/vd.h
@@ -15,6 +15,8 @@ typedef struct vd_functions_s
 // NULL terminated array of all drivers
 extern vd_functions_t* mpcodecs_vd_drivers[];
 
+extern int vd_use_slices;
+
 #define VDCTRL_QUERY_FORMAT 3 /* test for availabilty of a format */
 #define VDCTRL_QUERY_MAX_PP_LEVEL 4 /* test for postprocessing support (max level) */
 #define VDCTRL_SET_PP_LEVEL 5 /* set postprocessing level */