How to send a image with other parameters using retrofit?

I have successfully used retrofit for sending objects like this

@POST("/v2/createCustomer") void createCustomer(@Body Customer customer, Callback<Customer> callback);

Customer class is like this.

class Customer{ String name; String address; }

But i want another Parameter in customer object. That is to insert file. which is captured from mobile. To do this what else i want to change. Give one example