diff --git a/autocrop/autocrop.py b/autocrop/autocrop.py
index 230ef82..d7b8cbf 100644
--- a/autocrop/autocrop.py
+++ b/autocrop/autocrop.py
@@ -83,7 +83,7 @@ def check_positive_scalar(num):
 def open_file(input_filename):
     """Given a filename, returns a numpy array"""
     with Image.open(input_filename) as img_orig:
-        return np.asarray(img_orig)
+        return np.array(img_orig)
 
 
 class Cropper: