Minolta Company, Ltd.

Minolta Camera Kabushiki Kaisha

Minolta Camera Co., Ltd.

Tetsuya Itoh

Atsushi Ishikawa

Munehiro Nakatani

Kazuomi Sakatani

Shinji Yamamoto

Kazuaki Nakamura

Yoshikazu Ikenoue

Akio Nakajima

Nobuo Kamei

Keiji Nakatani

Toshikazu Kawaguchi

Hideo Kumashiro

Katsuaki Tajima

Norimichi Tsumura

Yoichi Miyake

Shigeru Sawada

Sou Hirota

Tomo Tsuboi

Shinji Okamoto

Makoto Niioka

An image not subjected to color correction, gamma correction, MTF correction and others is used as an image to be subjected to Retinex image processing. Thus, a RAW image prepared only by converting an electric signal of a CCD image sensor by an A/D converter into a digital form is used as an image to be subjected to the Retinex processing. Predetermined gamma correction is performed after the Retinex processing. Thereby, Retinex algorithm substantially modeling functions of a retina and a cortex of a living body exhibits its original performance. The resolution of the original image is lowered, and processing is performed on an image thus produced to produce a blurred image. Then, the resolution of the blurred image is restored to the same resolution as that of the original image, and the Retinex processing is performed. Thereby, the Retinex processing can be performed without increasing memory consumption and extremely lowering an operation speed.

Image processing program product and device for executing Retinex processing

An image processing apparatus includes a sort unit for sorting original image data into edge image data and planar image data, a first coding unit for coding the sorted planar image data according to the fractal block coding method, and a second coding unit for coding the sorted edge image data according to a coding method differing from the fractal block coding method. Thus, an image processing apparatus is provided that can have picture quality of a reproduced image improved even for a block that has maximum density difference such as an edge portion. The image processing apparatus can include a first coding unit for coding original image data according to the fractal block coding method, an extractor for extracting error between blocks, a comparator for comparing the amount of extracted error with a predetermined value, and a second coding unit for coding error information according to a coding method different from the fractal block coding method when the error amount is greater than the predetermined value as a result of comparison.

Image processing apparatus that can have picture quality improved in reproduced original image data

An image processing apparatus includes a brightness extracting element for extracting information relating to brightness from color image data; an image attribute judging element for judging a light-color image portion in a color image; and a brightness change section which changes brightness of the light-color image portion. The image attribute judging element includes a separating device for separating foreground data and background data from the color image data; and a comparing section which, when a difference in brightness between the foreground and the background separated by said separating device is smaller than a predetermined value, judges the foreground data as data of a light-color image portion.

Image processing apparatus

An image processing apparatus for forming an image on the basis of density data of respective picture elements corresponding to an original image, which includes a first memory for storing density data of the respective picture elements obtained by reading the original image, a multiline screen processing processor for processing the stored density data to add at least a part of density data of one of adjacent picture elements to that of another one, and a second memory for storing the processed density data. An image is formed by a printer on the basis of the density data stored in the second memory.

Image processing apparatus shifting image data between adjacent picture elements

A device for discriminating an attribute of an image in a block area contained in a document image includes a device for performing a Fourier transformation based on image data in the block area and for determining a spatial frequency spectrum relating to the image in the block area; and a neural network for outputting a discrimination result as to whether or not the attribute of the image in the block area is a halftone dot image based on the spatial frequency spectrum output from the Fourier transform device.

Network and image area attribute discriminating device and method for

Image compression is accomplished by dividing an image into blocks which are encoded and compressed by finding similarities among the blocks. Image quality and speed are increased through several mechanisms such as varying the size of the blocks when image edges or test is present, by comparing the image blocks to prestored image patterns rather than other portions of the image, using raw data rather than compressed data under certain conditions and the use of inspection areas to increase the possibility of finding the most similar area quickly.

Fractal image compression method and device and fractal image

A plurality of originals are successively read by an image scanner, and the read image data are stored in an image memory. A page layout control portion calculates maximum width and maximum length of an image output frame based on the read image data. A region defined by the maximum width and the maximum length to which the image data is to be output, is set for a sheet of paper, in accordance with a designated layout. The stored image data is successively output by a printing portion to the image output frame positioned on each sheet of paper.

Image forming apparatus capable of providing appropriate margin

An image forming apparatus with a solid-state scanning optical print head reproduces tones by an intensity modulation method, corrects light dispersion of each element by a pulse modulation method, and corrects fluctuations in sensitivity characteristics of a photosensitive member by switching the drive current value of maximum light exposure.

Image forming apparatus with a solid-state scanning optical print head

A print head for reproducing a multi-level image is an provided. In the print head, a light-emitting array comprises a linear line of light-emitting elements. A D/A converter converts a multi-level image data to an analog signal, and an analog shift register shifts and latches the analog signals of a line received from the D/A converter. An analog latch register latches the analog signals held by the analog shift register. A driver controls the quantity of light of the light-emitting elements according to the analog signals latched by the analog latch register. In one embodiment, the print head includes a second analog shift register, an A/D converter a line memory and a divider which divides the image data by a signal from the line memory to produce corrected data which is provided to the driver to control driving of the light-emitting elements. In another embodiment, the print head includes an amplifier and a gain correction circuit having a sample and hold circuit from which the driver receives signals to control driving of the light-emitting elements.

Print head with light-emitting element driving correction

In a shadow process mode, a scanner reads out an original with a first exposure lamp in a first scanning operation. The readout image data is stored in an image memory via an I/O control unit. In the second scanning operation, the scanner reads out the original with a second exposure lamp having an illumination direction different from that of the first exposure lamp. The image data read out in the second scanning operation and the data stored in the image memory are subtracted for each pixel by a subtractor. The difference thereof is compared with a predetermined value in a comparator. The compared result is output to a selector, whereby a desired image data is provided to a printer processing unit via the I/O control unit.

Image forming apparatus having illumination direction altered for every

In an image forming apparatus, when images are formed on a sheet on and after a second round of an image forming operation, an image forming pitch by a print head which linearly forms the images in the direction perpendicular to the image forming line is controlled so as to vary from the preceding pitch corresponding to the rate of expansion and contraction of the sheet in the preceding image forming operation. When images are formed on a sheet on and after the second round of the image forming operation, the length of the image to be formed is controlled for expansion and contraction corresponding to the actual rate of expansion and contraction automatically detected by a size detecting sensor in the preceding image forming operation.

Linear print head image forming apparatus with magnification adjustment

An image forming apparatus for forming an image composed of an assembly of a large number of picture elements arranged in a matrix. The apparatus includes a detector for detecting whether or not each of the picture elements is positioned in a corner of the image and a correcting circuit for reducing the size of the picture element positioned on the corner of the image, so that the picture element on the corner of the image acts to improve the linkage between the picture elements in the peripheral portion of the corner.

Image forming apparatus for forming an image with smooth curved lines

A method and apparatus for controlling an optical printer where respective light emitting elements are energized for light emission based on one line amount of received image data for a time equal to an ON time of a strobe signal thereby to form an image on a photosensitive member. The strobe signal is selected from a group consisting of a predetermined number of base signals each having a different ON time and one or a plurality of composite signals each composed of a different combination of the base signals. The one line amount of image data are outputted for a number of times equal to the number of base signals, within a time allotted for one line amount of exposure. The light emitting elements corresponding to the image data are energized for light emission for a time equal to the ON time of the selected strobe signal.

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Okazaki, Japan

Tetsuya Itoh