Abstract: A sensor produces an image signal indicative of the image of an original. The image signal is subjected to various types of processing by units ranging from an A/D converter 3 to a space filter 13. In an ordinary operating mode, the processing signal is subjected to a .gamma. conversion by a .gamma. conversion table set by a controller 21. If a gradation processing mode has been designated by the user, gradation processing is executed by a gradation processing conversion table set by the controller 21.

Abstract: Method to improve the printing quality at reproduction of half-tone originals by means of printers of the type, in which a number of dots are brought together in a cell (pixel). A minimum of two dots form a cell where each dot in the cell is controlled individually with respect to the size and/or the color value. The dots form a pattern in each cell, which is variable with respect to the number of dots, the dot size and/or the dot color value.

Abstract: A book page document image reading apparatus includes a page turning mechanism, a reading mechanism for reading an image of a spread book page document placed thereon with a binding section being aligned to a reference position, an image size changing mechanism for changing a size of a read image read by the reading mechanism, a storage mechanism for storing therein image data corresponding to an image size changing operation, and a mechanism for differentiating a range for storage of the image data having been subjected in the storage mechanism when a book page document is read with the same size from a range for storage of image data having been subjected to the image size changing operation in the storage mechanism when a book page document is read with a changed size.

Abstract: An image processing apparatus includes a K histogram calculating device for calculating a histogram of the density of a color image, after conversion to a monochrome image, and for converting it to a digital signal. Further, the apparatus includes a first reference density level calculating device for calculating a first reference density level corresponding to the density of white regions of the color image; a second reference density level calculating device for calculating a second higher reference density level; a third reference density level calculating device for calculating a third reference density level corresponding to the density of black regions of the color image; and a fourth reference density level calculating device for calculating, based on the second and third reference density levels, a fourth reference density level corresponding to an intermediate density of the color image.

Abstract: A color image-forming machine 08/715 000 includes a color image signal-forming device for outputting digital signals Cd, Md and Yd expressing, on tone levels, the three primary colors C, M and Y for a number of pixels, and a masking device for correcting the digital signals Cd, Md and Yd in compliance with masking operation expressions. A color region discrimination device is provided to discriminate, based on the digital signals Cd, Md and Yd, to which one of a plurality of predetermined color regions each of a number of pixels belong. The masking device corrects the digital signals Cd, Md and Yd by selecting different masking operation expressions depending upon each of the plurality of color regions.

Abstract: A method for maintaining the uniqueness of user entered data in a system for processing machine readable forms. Use of such a method in a system for processing machine readable forms facilitates forms reuse by creating keyword objects for new instances of user entered data, thus avoiding the creation of duplicate data. When user entered data is encountered in a machine readable form, the user entered data is compared to keyword objects of previously encountered user entered data. If no match is found, a new keyword object is created for the user entered data. Otherwise, it is assumed that the user entered data is a copy of previously entered data.

Abstract: An image processing apparatus is provided with (1) a linear CCD for, upon receipt of an image in the form of light, serially outputting an analog signal, or a signal of each pixel of the image, in sync with and under the control of a first clock, (2) a digital converting circuit for receiving the analog image signal and converting the same into a digital image signal in sync with and under the control of a second clock, and (3) a driving circuit for generating the first and second clocks in such a manner that the rising edges in the former are skipped with respect to those in the latter. Thus, the present apparatus can enlarge an original image only by generating the first clock to have fewer rising edges than the second clock by periodical skipping, thereby making it possible to simplify the enlarged-scale processing.

Abstract: An apparatus and method for color image adjustment which ensure proper saturation adjustment by a simple process. Color image data for three primary colors are adjusted so that the sum of the color image data for the three primary colors is kept unchanged before and after the adjustment. Thus, the saturation adjustment can be achieved without a change in the brightness of an image.

Abstract: A color correcting device and a color correcting method in an image forming apparatus such as a color copying machine that rely on, a correction factor in a masking equation which is previously found for each predetermined hue range. It is judged which of a plurality of predetermined hue ranges corresponds to a hue corresponding to input data composed of color data in a plurality of colors. The input data is subjected to color correction using a masking equation using a correction factor corresponding to the judged hue range.

Abstract: In a device for processing a signal representative of a document image from a document reading unit to thereby reproduce the document image, a first comparator binarizes a multilevel image signal from the document reading unit with a first threshold value to thereby output a first bilevel image signal. A second comparator binarizes the multilevel image signal with a second threshold value to thereby output a second bilevel image signal. An area discriminating circuit outputs, in response to the second bilevel image signal, an area discriminate signal representative of the inside and or outside of an image area of the document image. An area separating circuit outputs, in response to the area discriminate signal and first bilevel image signal, an image signal representative of only an image portion of the first bilevel image signal which corresponds to the area discriminate signal. The device is capable of reproducing both a sheet document and a book document accurately.

Abstract: An image recording method in which a head, in which a plurality of recording elements are arranged in the main scanning direction, is moved in the sub-scanning direction, one of densities and area rates of respective pixels being varied in accordance with image densities, respective colors of yellow,. magenta, cyan and black are combined so as to record multicolor images, the method including the step of: recording the respective colors in a pattern in which a dot pitch was randomly arranged only in the sub-scanning direction. Further, recording a color in a pattern in which a dot pitch was ordinarily arranged in the sub-scanning direction, and recording the other colors in a pattern, in which the dot pitch was randomly arranged only in the sub-scanning direction, could also be performed.

Abstract: A method for printing on a recording medium or on a cassette having the recording medium housed herein includes the steps of ejecting the ink by a first ink-jet printing head on the surface of the recording medium or of the cassette having the recording medium housed in it in a direction at right angles to the surface for forming an underlying layer, ejecting the ink by a second ink jet printing head supplied with data based on the printing picture information on the surface in a direction at right angles to the surface for forming a color printing layer on the underlying layer, and ejecting the ink by a third printing head on the printing layer in a direction at right angles to the surface for forming a protective layer.

Abstract: A digital color printing method and system is described which automatically determines a mixture of colorants to compose a process black color, taking into account relevent printing characteristics of a color printer and the background color at the point on the page at which the process black is to be printed. In certain printing systems, printing problems can occur when process black, composed of a mixture of colorants such as cyan, magenta, yellow, and black, is printed over a color background. For example, in a xerographic color printing system, a process black containing all colorants at maximum or near-maximum value can sometimes produce objectionable deletions in a surrounding color field, caused by interference in the transfer of toner to the background color field due to the process black toner pile height. Excessive combined toner pile height can also create an unevenness in the final print.

Abstract: An apparatus and method is provided for maximizing the number of digital radiological images displayed on a single sheet of film. Digital radiological frames, including radiological images and non-image portions, produced by a computer tomography device, a magnetic resonance imaging device, an ultra device or other radiological equipment are first stored. The radiological image portion of the frames are then identified and the non-image portion of the frames are reduced, producing a modified radiological frames. Finally, the modified radiological frames are arranged relative to one another in an area corresponding to the area of a sheet of film and printed on a sheet of film.

Abstract: An output writer includes an output scanner and optics that creates printed pixels along curved scan paths. Provided that a source of input image pixel value data presents data with pixels to be positioned in a rectangular coordinate system with a constant distance in an x-direction between adjacent input pixels, a position is determined along the curved scan paths of a pixel to be printed. The difference between the position of the pixel to be printed and the positions in the rectangular coordinate system of associated input pixels is determined, and then a value for the pixel to be printed is determined as a function of (1) the value data of the associated input pixels and of (2) the determined difference between the position of the pixel to be printed and the positions of the associated input pixels.

Abstract: Image data is separated into two colors to obtain two-color image data to form a two-color image. The two-color image data is reversed to obtain reversed two-color image data, which is output to an image forming device which forms an image of two colors.

Abstract: A color image processing apparatus including a read device for reading an original image, a color correcting device for color-correcting input image data using a color-correcting neural network, and an output device for outputting color-corrected image data. The neural network with teacher data, which are in effect learning color data reflecting the visual characteristics of human eyes, using learning data produced by reading a copy image produced based on the learning color data. Accordingly, the neural network can correct colors accurately in a manner to fully reflect the visual characteristics of human eyes, thereby making the color difference between the original image and a copy of the same less noticeable.

Abstract: A halftone screen generator, halftone screen and a method for making the halftone screen are described. The halftone screen has a screen angle and rulings that define the theoretical centers of gravity of the halftone dots. The actual centers of gravity of the halftone dots are displaced from the theoretical centers of gravity by the length and angle of random phase vectors. In one example, the positional displacement of the centers of gravity of the dots is dot size dependent in an inverse relationship. The shift in dot centers of gravity away from the theoretical centers of gravity defined by the halftone screen effectively breaks up screen "patterning" and avoids objectionable halftone "graininess".

Abstract: A light source apparatus for a scanner secures a uniform illuminance. The light source apparatus includes a plurality of light emitting diodes arranged at regular intervals. The light emitting diodes disposed at the periphery are provided with a higher voltage and the light emitting diodes disposed at near the center are provided with a lower voltage, so as to compensate for a loss of the light beam at the outer side. Further, the light source apparatus includes a constant-current source for providing the light emitting diodes with a constant current.

Abstract: An image forming apparatus using a photosensitive body (1) having high gamma characteristics has an exposure unit that is provided with a radiation element whose exposure value is variably set and which is capable of blinking on a pixel-by-pixel basis. An exposure controller (6) is provided with an exposure pattern determining unit (7) that determines an exposure pattern according to the image pattern, and an exposure value switching unit (8) that switches between an exposure value A1 at which the potential of the photosensitive body (1) sharply attenuates and an exposure value A2 at which the potential of the photosensitive body (1) does not substantially attenuate, on the basis of the exposure pattern determined by the exposure pattern determining unit (7).