Update app.py

app.py

@@ -387,9 +387,10 @@ def apply_mask(d, b):
     global frame_selected
     global masks
 
+    mask = cv2.cvtColor(d["layers"][0], cv2.COLOR_RGBA2GRAY)
     dilation = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (2 * b + 1, 2 * b + 1), (b, b))
-    d["layers"][0] = cv2.dilate(d["layers"][0], dilation)
-    d["background"][d["layers"][0]==(255,255,255,255)] = (255,255,255,255)
+    mask = cv2.dilate(mask, dilation)
+    d["background"][mask==255] = (255,255,255,255)
     
     masks[frame_selected] = d["background"]
     cv2.imwrite(f"f{frame_selected}_dmap.png", masks[frame_selected])