A plurality of apparatuses can execute an encrypting process on an image signal are connected. The encrypting processes which are executed in those apparatuses are independently performed, so that the connection of an improper apparatus is made impossible and, in this state, a more advanced signal process can be performed, thereby giving no disadvantage to the user. For this purpose, there is disclosed an image processing apparatus comprising a first encrypting circuit for encrypting the image data and supplying to a first apparatus and a second encrypting circuit for encrypting image data and supplying to a second apparatus different from the first apparatus, wherein the first and second encrypting means execute independently the encryption.