bluray: implement overlay wiping

Fixes duplicate menu selector images with some HDMV discs.
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/access/bluray.c

@@ -1180,12 +1180,10 @@ static void blurayDrawOverlay(demux_t *p_demux, const BD_OVERLAY* const ov)
      * Compute a subpicture_region_t.
      * It will be copied and sent to the vout later.
      */
-    if (!ov->img)
-        return;
-
     vlc_mutex_lock(&p_sys->p_overlays[ov->plane]->lock);
 
     /* Find a region to update */
+    subpicture_region_t **pp_reg = &p_sys->p_overlays[ov->plane]->p_regions;
     subpicture_region_t *p_reg = p_sys->p_overlays[ov->plane]->p_regions;
     subpicture_region_t *p_last = NULL;
     while (p_reg != NULL) {
@@ -1193,9 +1191,20 @@ static void blurayDrawOverlay(demux_t *p_demux, const BD_OVERLAY* const ov)
         if (p_reg->i_x == ov->x && p_reg->i_y == ov->y &&
                 p_reg->fmt.i_width == ov->w && p_reg->fmt.i_height == ov->h)
             break;
+        pp_reg = &p_reg->p_next;
         p_reg = p_reg->p_next;
     }
 
+    if (!ov->img) {
+        if (p_reg) {
+            /* drop region */
+            *pp_reg = p_reg->p_next;
+            subpicture_region_Delete(p_reg);
+        }
+        vlc_mutex_unlock(&p_sys->p_overlays[ov->plane]->lock);
+        return;
+    }
+
     /* If there is no region to update, create a new one. */
     if (!p_reg) {
         video_format_t fmt;
@@ -1267,6 +1276,7 @@ static void blurayOverlayProc(void *ptr, const BD_OVERLAY *const overlay)
         blurayActivateOverlay(p_demux, overlay->plane);
         break;
     case BD_OVERLAY_DRAW:
+    case BD_OVERLAY_WIPE:
         blurayDrawOverlay(p_demux, overlay);
         break;
     default: