diff --git a/ppdet/engine/callbacks.py b/ppdet/engine/callbacks.py
index ece2ca8b36b0d9c665d7b2246a73473be985d72a..1f2d546d86e9473c5dd6b7fd15068c940006dab5 100644
--- a/ppdet/engine/callbacks.py
+++ b/ppdet/engine/callbacks.py
@@ -413,7 +413,7 @@ class WandbCallback(Callback):
 
                 ips = float(batch_size) / float(batch_time.avg)
                 data_cost = float(data_time.avg)
-                batch_cost = f
+                batch_cost = float(batch_time.avg)
 
                 metrics = {"train/" + k: v for k, v in training_status.items()}
 
diff --git a/requirements.txt b/requirements.txt
index 0cdbf8e222c4aab26990e55121e3c1aaeb980f97..f6297b6f7849b4f8c33be4d4386bcddce4b26665 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,11 +11,10 @@ Cython
 pycocotools
 setuptools
 
-# for vehicleplate
-pyclipper
-
-# for mot
+# for MOT evaluation and inference
 lap
 motmetrics
 sklearn==0.0
-filterpy
+
+# for vehicleplate in deploy/pipeline/ppvehicle
+pyclipper