README.md in carrierwave-base64-2.3.2 vs README.md in carrierwave-base64-2.3.3

@@ -40,9 +40,15 @@
 
 ```ruby
 mount_base64_uploader :image, ImageUploader, file_name: 'userpic'
 ```
 
+You can also pass a Proc for the file-name to allow dynamic filenames.
+
+```ruby
+mount_base64_uploader :image, ImageUploader, file_name: -> { "file-#{DateTime.now.to_i}" }
+```
+
 ## Data format
 
 The string with the encoded data, should be prefixed with Data URI scheme format:
 
 ```