diff --git a/image_decode_cv2.py b/image_decode_cv2.py
index 1ae50cb..b6a6012 100644
--- a/image_decode_cv2.py
+++ b/image_decode_cv2.py
@@ -14,7 +14,7 @@ from towhee.utils.log import engine_log
 
 
 @register(
-    input_schema=[(str, (-1,))],
+    input_schema=[(str, (1,))],
     output_schema=[(Image, (-1, -1, 3))]
 )
 class ImageDecoder(PyOperator):