diff --git a/utils/datasets.py b/utils/datasets.py
index 29a8812a20a2..4f2939d4bef2 100755
--- a/utils/datasets.py
+++ b/utils/datasets.py
@@ -300,7 +300,8 @@ def update(self, index, cap):
             # _, self.imgs[index] = cap.read()
             cap.grab()
             if n == 4:  # read every 4th frame
-                _, self.imgs[index] = cap.retrieve()
+                success, im = cap.retrieve()
+                self.imgs[index] = im if success else self.imgs[index] * 0
                 n = 0
             time.sleep(0.01)  # wait time