PURPOSE: To attain optimum color reproduction in response to plural kinds of input data characteristics without imposing a load onto a host computer.

CONSTITUTION: The output device is provided with an input section 11 entering picture data such as data of a command form for output control and image data received from an external device, an analysis section 12 analyzing input data, an expansion section 13 expanding the input data into output data according to the result of analysis, a color processing section 14 implementing color processing such as color space compression with respect to the input data in the case of expansion, a color processing method storage section 16 storing plural color processing methods in the color processing section 14, and a selection section 15 selecting one among the plural color processing methods stored in the storage section 16, and the output device uses a proper color space compression method depending on the input picture data when the input picture data are expanded into the output data in the expansion section 13.