diff --git a/tools/show.py b/tools/show.py
index 9ac7bcf..2548bf7 100644
--- a/tools/show.py
+++ b/tools/show.py
@@ -11,6 +11,8 @@ import os
 def DumpTensorToImage(tensor, name, forceSquare=True, scale=1.0, AutoContrast=True, GridValue=0):
     if len(tensor.shape) != 2 and len(tensor.shape) != 1 and len(tensor.shape) != 3:
         raise ("Error input dims")
+    if ("." not in name) or (name.split(".")[-1] not in {"jpg", "png", "bmp"}):
+        raise ("Error input name")
 
     if len(tensor.shape) == 3:
         channel = tensor.shape[0]