Patent US 6,134,025

An output apparatus capable of receiving multi-level dot information of a first recording dot density, generating multi-level dot information of a second recording dot density, and transmitting the thus-generated second dot information in a visible way. The output apparatus comprises: a receiving device capable of receiving multi-level dot information of a first recording dot density; a generating device capable of generating multi-level interpolation dot information by applying a predetermined calculation to the thus-received multi-level dot information; and a dot density conversion device capable of generating multi-level dot information of a second, higher recording dot density from said interpolation dot information and the received multi-level dot information, whereby high density image data can be generated from low density image data.