Ricoh Company, Ltd.

Takahiro Ike

Takashi Kimura

Masanori Hirano

Masakazu Yoshida

Shigetoshi Hosaka

Takashi Mori

Naoki Kikuchi

Tomohiro Inoue

Naoya Morohoshi

Yoshihisa Ohta

Michio Umezawa

Naoki Nakano

A disclosed method for setting multiple tones in a halftone process upon recording an image using ink includes the steps of: dividing the image into plural dot areas; and setting the multiple tones such that at least one dot area to which the ink is not attached is present between dot areas to which the ink is attached.

Method and device for setting multiple tones in halftone process to prevent mixing of adjacent ink dots

An image forming method is disclosed in which an image is formed on commercial printing paper using a high penetration pigmented ink by performing image processing which makes use of dot patterns corresponding to an output halftone level.

Image processing method, program, image processing apparatus, image forming apparatus, image forming system

An imaging method is disclosed for realizing full color printing using an ink head configured to discharge black ink and a plurality of color inks. The imaging method involves printing a monochrome image portion by printing a plurality of first rasters using black ink and an arbitrary number of the color inks, and printing a second raster in between the first rasters using pseudo black ink that is realized by the remaining number of the color inks.

Imaging method and inkjet recording apparatus

A disclosed inkjet recording apparatus for performing recording by jetting a recording liquid onto a recording medium includes an image processing unit configured to obtain an output halftone level by performing halftone processing on input image data, to select a dot arrangement order according to the obtained output halftone level, and thereby to generate dot data where dots are arranged in a grid-like pattern. The disclosed inkjet recording apparatus is configured to use a pigmented ink as the recording liquid when the recording medium is a commercial printing paper, and to record the dots in a staggered arrangement where positions of the dots in odd/even-numbered columns or odd/even-numbered rows in the dot data are shifted in a sub-scanning direction or in a main-scanning direction.

Inkjet recording apparatus, image processing method, storage medium, pigmented ink, and recorded matter

A disclosed dither matrix is used in halftone processing for converting input image data having M input halftone levels into output image data having N (M&#x3e;N&#x3e;2) output halftone levels. In the halftone processing, a concentration type dither matrix is used as the dither matrix when an input halftone level is within a range of input halftone levels corresponding to an output halftone level that is lower than a predetermined threshold level T (N&#x3e;T&#x3e;1), and a dispersion type dither matrix is used as the dither matrix when the input halftone level is within a range of input halftone levels corresponding to an output halftone level that is equal to or higher than the predetermined threshold level T.

Dither matrix, image processing method, storage medium, image processing apparatus, image forming apparatus, and image forming system

In an image processing method for carrying out a plurality of types of halftoning processing expressing in combination amplitude modulation having the number of tone levels smaller than that of an input image and area coverage modulation, selectively or in parallel, the plurality of types of halftoning processing comprises processing providing output image color and tone substantially identical mutually.

Image processing method, program and apparatus having plural halftoning methods including error diffusion using a larger number of bits

An image-processing apparatus for quantizing multi-level (M-level) image data into N-level values, where M&#x3e;N&#x3e;1, using a multi-level error-diffusion process or a minimum-average multi-level error method is disclosed. The image-processing apparatus includes: means for outputting correction data; means for setting a quantization-threshold value; means for comparing the correction data and the quantization-threshold value so as to output N-level image data; and means for calculating an error generated with generating the N-level image data.

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Tokyo, Japan

Takahiro Ike