Abstract: A virtual, real-time proofing system and method are shown. The system and method are characterized in that a reconstructed image of a plurality of engraved cells is created using a pixel data signal that is created using a tool path position signal generated by a sensor that senses the movement of a cutter or stylus as it is engraving the cells.

Abstract: Disclosed is an image forming device including a fixing unit that fixes a first image to be fixed onto a sheet, the first image to be fixed being supported on the sheet, a target fixing temperature varying unit that varies a target fixing temperature during a time period in which a fixing process is performed, and a gradation processing unit that applies a gradation process to first image information. The target fixing temperature varying unit varies the target fixing temperature for the sheet of the recording medium to which the fixing process is applied, depending on presence or absence of a halftone process, and depending on a type of the gradation process to be utilized.

Abstract: When an image processing apparatus of one aspect of this invention corrects input image data using correction values (misregistration correction amounts ?y), it determines whether or not image data to be corrected using amounts ?y includes a specific pattern which may cause density unevenness in an image to be formed. When the image processing apparatus determines that the image data includes the specific pattern, it modifies amounts ?y corresponding to pixels including the specific pattern of the amounts ?y using any of a plurality of different predetermined modulation amounts (modification values). Furthermore, the image processing apparatus corrects the image data for respective pixels using either the amounts ?y before modification, or the modified amounts ?y when the modification is done.

Abstract: A target pixel is processed according to a blended combination of two or more error diffusion techniques. For example, the two or more techniques may include a standard error diffusion technique and rank ordered error diffusion. Additionally, or alternatively, a quantization resolution is selected for the target pixel based on information regarding the pixel. For example, a quantization resolution is selected based on a relative position of the target pixel or based on a value of the target pixel and/or values of pixels neighboring the target pixel.

Abstract: What is disclosed is a novel system and method for minimizing dot visibility in color marking devices capable of dot-on-dot printing. The present method achieves minimum dot visibility for a given dispersed-dot screen by performing a CMYK to CMYKRGB conversion which uses less visible dots as much as possible before more visible dots are introduced. The output color dot coverages are calculated sequentially to minimize the coverage of more visible dots in a decreasing order of brightness. Resulting images have noticeably reduced halftone graininess, particularly in the mid to darker tone areas. The present method is also computationally efficient.

Abstract: An image processing apparatus for converting a multiple gradation image into a binary or multivalue image by use of an area gradation method according to a screen cell is provided. The apparatus includes a receiving unit that receives an input pixel value of each pixel of the multiple gradation image and position information on the screen cell, an output unit that has a lookup table storing an output pixel value corresponding to the input pixel value in such a manner that an image is formed in which the output pixel value is increased or decreased with an increase in the input pixel value, and a screen line number is kept at a prescribed level with the increase in the input pixel value but a dot position is different, and that outputs the output pixel value at a pixel position on the screen cell corresponding to the position information by referring to the lookup table, according to the input pixel value and the position information received by the receiving unit.

Abstract: An image processing method generates a halftone image by forming a halftone dot represented by a set of one or plural output dots corresponding to an intensity of an input image signal while making a part of the dots constituting the halftone dot to be an actual non-output dot so as to reduce an amount of a coloring material of a halftone-dot portion. The image processing method includes holding in a predetermined storage medium halftone-dot profile data for forming the halftone dot corresponding to the intensity of the image signal and gap-size profile data representing a size of a set of the non-output dot; and generating the halftone dot comprising a gap having a size based on the gap-size profile data, a size of the halftone dot being based on the halftone-dot profile data.

Abstract: An image forming apparatus for forming a color image of CMK color plates by electrophotography system in which a K color plate having highest visibility among CMYK colors is composed of a rational number mesh. Profile of halftone dots (201Kh) becomes constant substantially and the factor for generating streak and unevenness is suppressed. Furthermore, C color plate and M color plate are formed of super cells and the K color plate, C color plate and M color plate are formed at an interval of 30°. Consequently, a Rosetta formed of halftone dots (201Ch, 201Mh, 201Kh) of CMK is optimized and the factor for generating moiré component is suppressed.

Abstract: The present invention provides an image-forming method, including pseudo-halftone-processing an input signal corresponding to image information to generate an output signal; irradiating a radiation beam corresponding to the output signal onto a latent image-holding member to form a latent image; developing the latent image with a developer including a toner containing a binder resin and a colorant to form a toner image on the latent image-holding member; transferring the toner image onto a recording medium; and fixing the toner image on the recording medium to form an image, wherein: when a halftone image is formed as the image, the toner image formed on the latent image-holding member is composed of plural toner aggregates scattered like dots on the latent image-holding member; the diameter of the radiation beam irradiated onto the latent image-holding member is 35 ?m or more; the pseudo-halftone processing results in the toner aggregates, which have been transferred onto the recording medium, having uneven

Abstract: An image processing device for processing an input image so as to reproduce a halftone, includes: a matrix setting section for setting a threshold matrix having a plurality of elements arranged in M columns×N rows, at least two threshold values being stored in each of the elements; an element specifying section for specifying a corresponding element of the threshold matrix in accordance with a position of a pixel in the input image; and a multilevel signal generating section for fetching the threshold values from the specified element and for generating a multilevel signal by transforming an input pixel value to one of multiple levels in accordance with the fetched threshold values; wherein the multilevel signal generating section outputs a constant value Doutmin as the multilevel signal when a first condition that the input pixel value is smaller than or not larger than a minimum value of the threshold values, is satisfied; the multilevel signal generating section outputs a constant value Doutmax when a seco

Abstract: Conventional design tools were not developed for designing square zero-shift supercells. Conventionally, solutions that enable square zero-shift supercells were found by trial and error or by exhaustive analysis. According to a first design criterion of this invention, a non-square supercell in a first frame of reference has a diagonal that is equal in length to the diagonal of a square supercell in a second frame of reference rotated at a desired screen angle to the first frame of reference. The screen angle is a function of the lengths of the sides of the non-square supercell in the first frame of reference. According to a second design criterion, if the area of the corresponding square supercell in the second frame of reference is an integer, a square zero-shift supercell can be designed based on the lengths of the sides of the non-square supercell in the first frame of reference.

Abstract: Digital watermark embedding is incorporated into processes for generating halftone images. In a halftone process using a halftone screen, the halftone screen is used to determine the geometric distortion of an image. After determining the geometric distortion, a watermark decoder compensates for this distortion and retrieves an embedded digital watermark.

Abstract: An integrated circuit fabricated on a single substrate that includes a data bus and purpose-specific functional units connected to the data bus. The functional units include a halftoner and a printhead interface. A general-purpose processor is connected to the data bus for controlling the functional units, and for coordinating the functional units to print pages. The halftoner may halftone contone color data to a bi-level color layer, and then composit a bi-level black layer over the bi-level color layer.

Abstract: An image forming apparatus includes an electrophotographic developing device, a photosensitive body, a precharger for precharging the photosensitive body, and exposing units of two optical systems with different light amount distributions, which are provided for one photosensitive body for forming electrostatic latent images on the photosensitive body. The exposing units are selectively used.

Abstract: Methods embed a digital watermark into a halftone image. One method derives halftone thresholds from a watermark image, and then uses these thresholds to convert target images into watermarked halftone images. A method for measuring digital watermark strength is used for a variety of applications, such as distinguishing original printed documents from copies. In this method, a watermarked signal is processed to extract estimates of error correction encoded bits embedded into the watermarked signal. Then, the error correction encoded bits are decoded to compute a message payload. The message payload is re-encoded to compute error correction encoded bits. A measure of watermark strength is computed from the error correction encoded bits and the estimates of error correction encoded bits.

Abstract: An image forming apparatus has a latent image carrier on which a latent image is formed. A developer carrier conveys a one-component non-magnetic developer and develops the latent image either in close proximity to or in contact with the latent image carrier. A voltage application unit applies an AC-superimposed bias voltage to the developer carrier. A regulating member abuts against the developer carrier to regulate the thickness of the developer layer on the developer carrier. The regulating member has a semiconductive member provided at the distal end thereof to produce an electric potential difference between the semiconductive member and the developer carrier, to which the AC-superimposed bias voltage is applied, when regulating the thickness of the developer layer on the developer carrier, thereby forming a line-shaped uneven conveying surface. Thus, the occurrence of banding and longitudinal unevenness and stripes is prevented, and fogging and scattering are also prevented.

Abstract: A method for achieving multiple exposure levels for IOI (IMAGE-ON-IMAGE) xerography when imaging a second color through a first toner layer previously developed on the photoreceptive member. In the example illustrated the data from the previous image paths (magenta and yellow) is analyzed. If the signal indicates that a magenta or yellow bit is present, the cyan output bit information passes to the ROS unchanged, or at full intensity. If however, the magenta and yellow are not present, a modified pattern providing an appropriate reduced exposure signal is sent to the ROS. The process of laser attenuation is blended with halftoning logic to avoid image degradation due to the attenuation.

Abstract: In an electrophotographic printing apparatus for printing using a three level printing method, there are provided a first color data memory and a second color data memory which memorize the pixel data of every color sent from host equipment, such as a computer connected to an electrophotographic printing apparatus, and by the use of image recognition equipment for judging whether pixel information is part of what image, exposure information with exposure equipment is determined so that the electric current flowing into electric current source and electric current source is changed. With such an arrangement, the exposure data for every color to be printed is created on the basis of the recognized result the part of a particular image that the pixel data shows, and the color image of the line-width in accordance with data sent from the host equipment to the electrophotographic printing apparatus can be actually printed by controlling the exposure beam diameter.

Abstract: A color image forming method, including the steps of: charging a front surface of a photoreceptor; conducting image wise exposure onto the charged front surface from a rear surface of the photoreceptor so that a latent image is formed on the front surface; developing the latent image with a color toner so that a color toner image is formed on the front surface; and repeating the steps of charging, conducting image wise exposure and developing so that a multicolor toner image is formed on the front surface; in which a secondary color of the multicolor toner image, which consists of two color toner images, is formed in a manner that the two color toner images are formed by conducting the image wise exposure at a same exposure amount; and the first one of the two color toner images is formed by conducting the image wise exposure at an exposure amount which creates a potential smaller than that of already formed primary color of the multicolor toner image, which consists of single color toner image.

Abstract: An improved method for estimating toner usage in digital xerographic printers and copiers. The method is characterized by taking into account digital image dot spreading which results in the area of a pixel not being developed fully and some areas outside of the pixel being developed. Thus, the improved method takes into account the departure of a developed image from an ideal shape (i.e. square). To this end, the improved method compensates for departure of a developed image from an ideal shape. In carrying out the method estimated toner usage is based on pixel groupings rather than simple pixel counting.

Abstract: A pixel matrix preferably containing nine pixels is analyzed to determine whether or not all of the image values for the pixels in the pixel matrix correspond to a full saturation level. If the image values do correspond to full saturation level, preferably the center pixel is produced using a variably reduced toner output. If all of the image values do not correspond to full saturation level, the center pixel is produced using conventional methods. The system of the preferred embodiment is comprised of an input buffer for storing the image values, a comparator for comparing the image values with a toner modification value to determine if the pixel or pixels should be produced using a variably reduced toner output. The pixels are then preferably stored temporarily in an output buffer and then sent to a memory to be produced.

Abstract: An electrophotographic copying machine adapted to operate in either a functional or a pictorial mode, such that, in the pictorial mode, a light signal is transmitted through a line screen member to modulate an electrostatic latent image of an original document. The amount of light transmitted through the line screen is varied as a function of the amount of light used to generate the electrostatic latent image to control the contrast of the image generated thereby. As a result, pictorial image contrast is readily adjustable by regulating the light intensity of the light transmitted through the line screen member and onto the photoconductive surface for high quality pictorial copies in an electrostatographic copying machine.

Abstract: An image forming apparatus includes an image bearing member for bearing a toner image, and a transfer member for transferring the toner image from the image bearing member onto a transfer material at a transfer position. The transfer member contacts a surface of the transfer material opposite to a surface facing the image bearing member so as to press the transfer material against the image bearing member. The apparatus is capable of selecting one of a first mode of forming a character image on the transfer material and a second mode of forming a halftone image on the transfer material. The apparatus also includes a changing unit for changing a speed ratio of a conveying speed of the transfer material at the transfer position to a circumferential speed of the image bearing member in accordance with a mode selected from among the first mode and the second mode.