Abstract: A print management system, includes a management unit to receive print manuscript data from a connected manuscript processor, and obtain status information indicating states of connected multiple output enabled printers; a status identification unit to predict whether the output enabled printers stop in the middle of a print job; and a print data generator to generate multiple types of print data whose amount of toner consumption during printing is different respectively, based on the print manuscript data. The management unit classifies the output enabled printers predicted that there is less possibility to stop in the middle of a print job as output candidate printers, and selects an output destination printer from the output candidate printers. The management unit selects one type of print data from the multiple types of print data, depending on the output destination printer, and outputs the selected print data to the output destination printer.

Abstract: A print management system, includes a management unit to receive print manuscript data from a connected manuscript processor, and obtain status information indicating states of connected multiple output enabled printers; a status identification unit to predict whether the output enabled printers stop in the middle of a print job; and a print data generator to generate multiple types of print data whose amount of toner consumption during printing is different respectively, based on the print manuscript data. The management unit classifies the output enabled printers predicted that there is less possibility to stop in the middle of a print job as output candidate printers, and selects an output destination printer from the output candidate printers. The management unit selects one type of print data from the multiple types of print data, depending on the output destination printer, and outputs the selected print data to the output destination printer.

Abstract: In an image processor, a data corrector corrects input image data, a determining unit determines an output tone value of a target pixel from the corrected image data and threshold, and a calculator calculates a difference between the output tone value and the corrected image data as an error value. The threshold is set in such manner that a rate of change of the mean error of the error values with respect to a change in the input tone value is within a predetermined range.

Abstract: An image processing method of quantizing multi-tone image data by an error diffusion method, includes the steps of a) detecting change of the image data; and b) oscillating cyclically in image space a threshold for the quantization in an oscillation range controlled according to the detection result of the step a).

Abstract: A filtering processing unit of an image processor includes a component extraction unit, a character edge quantity calculation unit, and a correction unit corresponding to each of a plurality of frequency bands and direction components, and an adder. The component extraction unit extracts signals from a corresponding one of the frequency bands and direction components. The character edge quantity calculation unit calculates a character edge quantity from an output of a corresponding one of the component extraction units. The correction unit performs correction control to the output of a corresponding one of the component extraction units based on a character edge quantity calculated by a corresponding one of the character edge quantity calculation units. The adder adds outputs of all the correction units.

Abstract: An image processing apparatus includes an edge amount calculating device configured to calculate edge amounts of an image in a plurality of directions for each of a plurality of frequency bands of the image. A character edge area determination device determines, based on the calculated edge amounts, whether or not a selected picture element of the image is of a character edge area. A sharpness control device corrects a frequency characteristic of the image by performing a first correction to the edge amounts when the selected picture element is determined to be of a character edge area by the character edge area determining device, and by performing a second correction to the edge amounts when the selected picture element is determined not to be of a character edge area by the character edge area determining device.

Abstract: An image forming apparatus adds a plurality of dots of image data in the subscanning direction and starts generating a density from a particular pixel, and switches PWM (Pulse Width Modulation) right and left phases in order to concentrate potentials and to increase a saturation region. It is therefore possible to stabilize image density in a highlight portion and therefore realize high quality images, while reducing banding and image noise.

Abstract: An image processing method of quantizing multi-tone image data by an error diffusion method, includes the steps of a) detecting change of the image data; and b) oscillating cyclically in image space a threshold for the quantization in an oscillation range controlled according to the detection result of the step a).

Abstract: An image processing apparatus includes a first filtering process device configured to perform a predetermined space frequency characteristic conversion process to input image data having multiple-level gradation. A conversion process device performs a gradation characteristic conversion process to an output result of the first filtering process device. A second filtering process device performs a predetermined space frequency characteristic conversion process to an output result of the conversion process device. A halftone processing device performs a quasi-gradation processing to an output result of the second filtering process device.

Abstract: An image processing method of quantizing multi-tone image data by an error diffusion method, includes the steps of a) detecting change of the image data; and b) oscillating cyclically in image space a threshold for the quantization in an oscillation range controlled according to the detection result of the step a).

Abstract: In an image processor, a data corrector corrects input image data, a determining unit determines an output tone value of a target pixel from the corrected image data and threshold, and a calculator calculates a difference between the output tone value and the corrected image data as an error value. The threshold is set in such manner that a rate of change of the mean error of the error values with respect to a change in the input tone value is within a predetermined range.

Abstract: An image processing method of quantizing multi-tone image data by an error diffusion method, includes the steps of a) detecting change of the image data; and b) oscillating cyclically in image space a threshold for the quantization in an oscillation range controlled according to the detection result of the step a).

Abstract: An image processing method of quantizing multi-tone image data by an error diffusion method, includes the steps of a) detecting change of the image data; and b) oscillating cyclically in image space a threshold for the quantization in an oscillation range controlled according to the detection result of the step a).

Abstract: An image forming apparatus adds a plurality of dots of image data in the subscanning direction and starts generating a density from a particular pixel, and switches PWM (Pulse Width Modulation) right and left phases in order to concentrate potentials and to increase a saturation region. It is therefore possible to stabilize image density in a highlight portion and therefore realize high quality images, while reducing banding and image noise.

Abstract: An image forming apparatus adds a plurality of dots of image date in the subscanning direction and starts generating a density from a particular pixel, and switches PWM (Pulse Width Modulation) right and left phases in order to concentrate potentials and to increase a saturation region. It is therefore possible to stabilize image density in a highlight portion and therefore realize high quality images, while reducing banding and image noise.

Abstract: A scanning unit reads an original color image and outputs an rgb signal of the color image. A scanner &ggr; correction unit that converts the rgb signal from the scanning unit into an RGB signal that is a density signal. A color converting unit converts the RGB signal into a CM signal. An edge amount calculating unit calculates an edge amount from the CM signal. A filter processing unit performs an adaptive filtering process for the RGB signal based on the edge amount.

Abstract: A filtering processing unit of an image processor includes a component extraction unit, a character edge quantity calculation unit, and a correction unit corresponding to each of a plurality of frequency bands and direction components, and an adder. The component extraction unit extracts signals from a corresponding one of the frequency bands and direction components. The character edge quantity calculation unit calculates a character edge quantity from an output of a corresponding one of the component extraction units. The correction unit performs correction control to the output of a corresponding one of the component extraction units based on a character edge quantity calculated by a corresponding one of the character edge quantity calculation units. The adder adds outputs of all the correction units.

Abstract: An image processing apparatus includes an edge amount calculating device configured to calculate edge amounts of an image in a plurality of directions for each of a plurality of frequency bands of the image. A character edge area determination device determines, based on the calculated edge amounts, whether or not a selected picture element of the image is of a character edge area. A sharpness control device corrects a frequency characteristic of the image by performing a first correction to the edge amounts when the selected picture element is determined to be of a character edge area by the character edge area determining device, and by performing a second correction to the edge amounts when the selected picture element is determined not to be of a character edge area by the character edge area determining device.

Abstract: An image processing apparatus includes a first filtering process device configured to perform a predetermined space frequency characteristic conversion process to input image data having multiple-level gradation. A conversion process device performs a gradation characteristic conversion process to an output result of the first filtering process device. A second filtering process device performs a predetermined space frequency characteristic conversion process to an output result of the conversion process device. A halftone processing device performs a quasi-gradation processing to an output result of the second filtering process device.

Abstract: There is provided by the present invention an image processing apparatus for outputting a multiple gradation color image with a printer which can express colors fewer than those specified in input image data comprising an output color predicting section for predicting colors, which will be reproduced by a printer, from color control signals given to the printer, an error computing/error adding section for computing an error between colors specified in input image data and those predicted by the output color predicting section, diffusing the error to peripheral pixels and adding the diffused error to a value of each of the pixels, and an output color selecting section for selecting colors to be reproduced by the printer, which are closest to colors specified in the input image data, according to an output from the error computing/error adding section.