Update app.py

app.py

@@ -174,8 +174,8 @@ def remove_bg(fl, count):
     fr_diff = cv2.dilate(cv2.erode(fr_diff, element), element)
 
     if count % 2: # odd: is photo without the flash
-        fr_mask = cv2.cvtColor(cv2.imread(fl_).astype(np.uint8), cv2.COLOR_BGR2GRAY)
-        fr_mask = (fr_diff - fr_mask).astype(np.uint8)
+        fr_mask = np.bitwise_not(cv2.cvtColor(cv2.imread(fl_).astype(np.uint8), cv2.COLOR_BGR2GRAY))
+        fr_mask = np.bitwise_and(fr_diff, fr_mask).astype(np.uint8)
         cv2.imwrite(fl_, fr_mask)
 
         m = cv2.inRange(fr, np.array([240,240,240]), np.array([255,255,255]))