Method of and apparatus for correcting print gradation, color converting apparatus with gradation correction, method of adjusting dot gain in print, and proofer used therein
An adjustment process for converting the dot gain of printing conditions of a given standard printing profile to the dot gain of printing conditions of a printing machine which is going to be used is facilitated. For example, with respect to the color cyan C, the printing profile is divided into a linear four-dimensional LUT for color conversion and a gradation characteristic inherent in the printing profile, i.e., an LUT of dot gain characteristics. The characteristic of an inverse function of the gradation characteristic inherent in the printing profile is set in a LUT for gradation characteristic conversion such that a change in output halftone-dot % of the LUT of the gradation characteristic inherent in the printing profile will be equalized to a change in input halftone-dot % of the LUT. In this manner, the input halftone-dot % and the output halftone-dot % agree with each other, allowing the adjustment process to match the user's sensitivity.
A method of copying a document onto a receiver such as paper includes taking the characteristics of the receiver into account in selecting pigments for making the copy. The characteristics may be determined by scanning the receiver to determine its color, finish, texture, etc. If the characteristics are other than a given standard such as white, the pigments necessary to render the receiver area(s) white are determined. Concurrently, the pigments needed for copying the document onto the receiver are also determined. An image processor then generates copy pigment data from the receiver and document pigments and transmits the data to a print engine in the form of toner data. If the copy pigment data might produce too dark a copy, the data is modified uniformly to reduce pigment percentages.
An object is to provide a print proof that takes account of halftone dots and operating conditions of a printing press. To achieve the object, a color image processing apparatus for producing the print proof comprises: a dot gain processing unit for receiving an input of halftoned binary image data, and for converting the binary image data to multi-value image data corresponding to the amount of dot gain of each color; a first color-converting unit for converting the multi-value image data to image data in a device-independent color space; a resolution converting unit for changing the resolution of the multi-value image in the device-independent color space to match the resolution of an output device; and a second color-converting unit for converting the multi-value image data, converted into the device-independent color space, to image data in a color space associated with the output device.
A flexible and extensible job processing system is described. A print job processing server manages a plurality of data receivers and printer emulators. Data receivers receive jobs from the print job originators, such as print servers. The printer emulators convert the jobs into a plurality of intermediate output formats, with error, status and control information being available for both storage and reporting back to the print job originator. A user interface client is used to communicate with a plurality of job processing systems. The client can be used to view and possibly edit the job and device information available by the print job originator, configure the printer emulators in the system and the system itself, view the job status and error information, including printer traces, and view and possibly edit the data output of the printer emulator. The system uses the output of the printer emulators for a variety of purposes, such as driving output devices. Configurable actions are taken on the data and status information as they are generated by the printer emulators.
