Hitachi, Ltd.

Other

Hitachi Computer Engineering Co., Ltd.

Hitachi Information Network, Ltd.

Masayuki Kanda

Tatsuki Inuzuka

Takeshi Shibuya

Atsushi Onose

Eiji Yoshino

Tadashi Okada

Akira Sasaki

Hitoshi Tamura

Toshiaki Nakamura

Nobuo Suzuki

Hiroyuki Tadokoro

Naoyuki Urata

Tadashi Tsuchiya

Tatsunari Satoo

Hirro Fujisaki

A personal computer has a print image developing means and a data compression means including a fixed rate compression. A color printer has a data extension means, a color correction means, a gamma correction means, a first halftoning means, an image area segmentation means, and a second halftoning means. The transmission time of a print image can be shortened necessarily to less than a constant time, and further, since an enormous memory for extension is unnecessary, a low cost printer can be provided.

Information print system and image processing apparatus

In a halftoning unit of a laser printer and the like, a high speed, high density and high gradations halftoning is realized by multi-value implementation by clustered dot concentrated dither halftoning (known as a sub-matrix method) and PWM distributing gradation among the plurality of halftone dots with a small memory and circuit. For this purpose, the value of the difference between an input gradation value n,and a threshold value n,, &Dgr;n&equals;n,&minus;n,, is shortened within a range of 0 to &Dgr;h and the lower s bit of &Dgr;h is removed by a round-down or round-up process. Meanwhile, a threshold array is generated from an extended threshold pattern obtained by combining threshold patterns of 2,whose threshold interval is &Dgr;h, i.e. &Dgr;Ah&times;K, &Dgr;h&times;K&plus;1, . . . , &Dgr;&times;K&plus;2,. Thereby, a halftone dot dither process in which the PWM gradation increases distributively among the 2,dots may be realized with a small scale memory and circuit.

Distributed PWM halftoning unit and printer

A storage control system for a print image data in a print control apparatus includes a unit for generating a print image expressed by a set of a plurality of dots as a digital data having a dot carrying a two-dimensional address corresponding to a bit, an address conversion unit for converting a digital data carrying a two-dimensional address into a digital data carrying a one-dimensional address, and a full-dot memory for storing a digital data carrying a one-dimensional address in a one-dimensional address structure.

Storage control system for print image data

Growing community of inventors

Hadano, Japan

Masayuki Kanda