TypeError (can't cast Enumerator to string): - Ruby on Rails

Hi,

When I am trying to upload a file through the url -
http://0.0.0.0:3000/upload/get . I am getting an error as

Started POST "/upload/save" for 127.0.0.1 at 2014-05-27 01:29:29 +0530
Processing by UploadController#save as HTML
  Parameters: {"utf8"=>"✓",
"authenticity_token"=>"khU59z0DsXoVyHeu4XNaUb7TEpSWZ9id4dJTbVu6efU=",
"picture"=>{"comment"=>"dfgjk",
"uploaded_picture"=>#<ActionDispatch::Http::UploadedFile:0xa939838
@tempfile=#<Tempfile:/tmp/RackMultipart20140527-11473-10esj62>,
@original_filename="sfnzf.png", @content_type="image/png", @headers="Content-
Disposition: form-data; name=\"picture[uploaded_picture]\";
filename=\"sfnzf.png\"\r\nContent-Type: image/png\r\n">}, "commit"=>"Upload
file"}
   (0.2ms) begin transaction
Binary data inserted for `string` type on column `content_type`
   (0.1ms) rollback transaction
Completed 500 Internal Server Error in 5ms

TypeError (can't cast Enumerator to string):
  app/controllers/upload_controller.rb:8:in `save'