A method of enhancing quality of an image object included in a compound document, and an apparatus for performing the method are provided. The method includes receiving a request to print a compound document including an image object, merging parts corresponding to the image object from among data corresponding to the compound document and enhancing the quality of the image object, and encoding data corresponding to the compound document by using a printer control language (PCL) and outputting the encoded data.

An image processing apparatus includes an image processor that performs error diffusion processing by applying an error diffusion matrix to multi-valued image data having pixels two-dimensionally arranged, so as to convert the multi-valued image data into binary image data. The binarization unit applies an error diffusion matrix in which the diffusion coefficient of a pixel diagonal to a focused-on pixel is greater than those of other pixels.

An image processing system for executing a plurality of processes includes a process execution control apparatus, and image generation-output control apparatuses of different types. The process execution control apparatus includes a process execution controller to control the processes, and to transmit a command information to the image generation-output control apparatuses. Each of the image generation-output control apparatuses includes a command information converter to convert the command information to a format processable by the image generation-output control apparatus, an imposition convertor to convert initial designation information to imposition process information processable by the image generation-output control apparatus, and an image drawing information generator to generate image drawing information.

There is provided an image forming apparatus configured to process print data of a plurality of pages includes a plurality of interpreters configured to generate intermediate data of the plurality of pages by interpreting the print data, a control unit configured to specify different pages for different interpreters, and, for each specified page, cause a corresponding interpreter to generate the intermediate data of the specified page or specified pages, and a generation unit configured to generate a raster image of the page based on the generated intermediate data, wherein, based on interpretation of the print data of an invalid page, any one interpreter of the plurality of interpreters generates the intermediate data of a page subsequent to the invalid page without requiring the page to be specified by the control unit.

An image forming output control device includes a duplicate image information detector to receive instruction information from a processing execution control apparatus, compare image information included in a plurality of objects being unit images constituting the instruction information, and detect a plurality of duplicate image information objects, in which the image information is duplicate with each other, in the objects in which identification information for identifying the objects is different from each other; a drawing information generation controller to control a drawing information generator to generate drawing information according to the instruction information; and a drawing result storage unit to store drawing result information being a drawing result of the image information. The drawing information generation controller controls the drawing information generator to generate the drawing information with the drawing result information of the image information included in the duplicate image information objects detected with the duplicate image information detector.

A method of enhancing quality of an image object included in a compound document, and an apparatus for performing the method are provided. The method includes receiving a request to print a compound document including an image object, merging parts corresponding to the image object from among data corresponding to the compound document and enhancing the quality of the image object, and encoding data corresponding to the compound document by using a printer control language (PCL) and outputting the encoded data.

An image forming output control device includes a duplicate image information detector to receive instruction information from a processing execution control apparatus, compare image information included in a plurality of objects being unit images constituting the instruction information, and detect a plurality of duplicate image information objects, in which the image information is duplicate with each other, in the objects in which identification information for identifying the objects is different from each other; a drawing information generation controller to control a drawing information generator to generate drawing information according to the instruction information; and a drawing result storage unit to store drawing result information being a drawing result of the image information. The drawing information generation controller controls the drawing information generator to generate the drawing information with the drawing result information of the image information included in the duplicate image information objects detected with the duplicate image information detector.

An image processing apparatus includes an image processor that performs error diffusion processing by applying an error diffusion matrix to multi-valued image data having pixels two-dimensionally arranged, so as to convert the multi-valued image data into binary image data. The binarization unit applies an error diffusion matrix in which the diffusion coefficient of a pixel diagonal to a focused-on pixel is greater than those of other pixels.