Minolta Camera Kabushiki Kaisha

Minolta Company, Ltd.

Shigeru Moriya

Keiji Nakatani

Toshio Tsuboi

Shoji Imaizumi

Kaoru Tada

Junji Nishigaki

Yoshihiko Hirota

Takayuki Nabeshima

Hideo Kumashiro

Hiroya Sugawa

Hiroshi Murakami

Katsuaki Tajima

Masamichi Kishi

Yoshikazu Naito

Takashi Noda

Kunihiko Omura

Takayoshi Hayashi

In an image processor, a decider decides based on image data of pixels included in a block whether the block has character attribute of non-character attribute, a first encoder encodes the image data with block truncation coding, and a second encoder encodes the image data which have been encoded by the first encoder. For a block of character attribute, the binarized data binarized by the binarizer are encoded by the first and second encoders. For a block of non-character attribute, the image data are encoded by the first and second encoders without binarization. In a different image processor, it is decide whether image data of pixels in an area consisting of a plurality of blocks are all character, all ground or mixture of character and ground. Then, an encoder encodes the image data in each block differently according to the decision.

Image processor for encoding image data

In an image processor, image data of red, green and blue are converted to image data of lightness and chromaticities, and they are divided into pixel blocks. Then, image data of each block are compressed to data having 4 gradation levels smaller than 256 levels of the image data by generalized block truncation coding. Then a capacity of image memory can be decreased. An attribute of the image data is decided for each block according to the compressed data. The attribute can be corrected by taking attributes of adjacent blocks into account. Edition of image data such as edge emphasis can be performed according to the attributes. The compressed data are further compressed by deleting data which can be specified according to the attribute.

Image processor

An image forming apparatus includes an encode process unit for: (a) allocating image data of an original document into blocks containing a predetermined pixel matrix, and (b) determining from the image data in each block a mean value information and a gradient range exponent for each block; a series copy data generating unit for generating reduction image data for a plurality of reduction images by using the mean value information for each of the blocks as image data for the reduction images so that each pixel of the reduction images corresponds to a respective one of the plurality of blocks of the original document image data; and an image forming unit for forming images based on the reduction image data generated by the series copy data generating unit.

Image forming apparatus and method based on reduction images and encoding

In an image processor, image data of red, green and blue are converted to image data of lightness and chromaticities, and they are divided into pixel blocks. Then, image data of each block are compressed to data having 4 gradation levels smaller than 256 levels of the image data by generalized block truncation coding. Then, a capacity of image memory can be decreased. An attribute of the image data is decided for each block according to the compressed data. The attribute can be corrected by taking attributes of adjacent blocks into account.

Image processor with image data compression capability

A method of image processing includes the steps of allocating image data of a document into a plurality of blocks of a predetermined pixel matrix; determining a gradient range exponent and a mean value information for each of the blocks based on the image data contained in each of the blocks; encoding the image data of each pixel of each of the blocks into code data based on the mean value information and gradient range exponent for the respective block so that the code data defines each pixel with fewer gradation levels than the image data; determining whether or not a mutually adjoining block is related to a solid image of a same density relative to a block subject to the encoding process; and executing a run length encoding process for a batch of mean value information, gradient range exponent, and code data based on a run length of adjoining blocks discriminated as related to a solid image of the same density.

Image processing device

A chromatic color pattern and a monochromatic color pattern are read by an image sensor. A masking coefficient in a color masking portion or a gamma conversion characteristic of a gamma correction portion are selected in accordance with the ratio V1/V0 of a read value V1 of the chromatic color pattern and a read value V0 of the monochromatic color pattern. An output of an image data is corrected by masking processing with the selected masking coefficient and the like.

Image reading apparatus having color correction according to tempeature

In an image processing apparatus, first peak density pixels of one dimension each having a peak density in one-dimension direction larger than a predetermined density are detected from image data located in a predetermined image area of a document image, and second peak density pixels of two dimensions each having peak densities in two-dimension directions larger than the predetermined density are detected from the image data. Further, there are counted a number of the detected first peak density pixels of one dimension and a number of the detected second peak density pixels of two dimensions, and then, it is judged whether or not the image data located in the predetermined image area are image data of a dot photograph image, a photograph image or a character image based on the counted numbers.

Image processing apparatus comprising judgement means for judging dot

Image data of a plurality of lines in a document are read in the main scan direction and/or in the subscan direction, and the document size is determined on the basis of the image data of the plurality of lines. Thus, the erroneous detection of document size can be avoided. The document size is determined for example as an average of the document sizes detected for lines except the smallest and largest document sizes. When the same anomaly is observed twice, new lines are used to determine the document size. Further, an image reading apparatus reads image data of a line in a document in the main scan direction and in the subscan direction with a linear image sensor. When the document size is detected on the basis of the image data of a plurality of lines in the main scan direction, the document is scanned in the subscan direction at a fast read rate, while the document size is detected on the basis of the image data of a plurality of lines in the subscan direction, the document is scanned in the subscan direction at a low read rate.

Image reading apparatus which detects document size

An image reading apparatus includes an original placing platen formed of a rectangular transparent member on which an original is placed; a photoelectrical conversion device for reading an image of the original-placed on the transparent member; an original pressing plate having an original pressing surface for pressing the overall surface of the original placing platen, the original pressing surface having a first area formed at a portion opposing a first side of the transparent member and a second area formed at a portion opposing a second side crossing at a right angle to the first side of the transparent member. The first and second areas are determined as a predetermined color by the photoelectrical conversion device. The apparatus further includes a size detecting device for reading by the photoelectrical conversion device the original sandwiched between the first and second areas of the original pressing surface and the transparent member so as to detect the size of the original based on the result of reading.

Image reading apparatus capable of detecting paper size

An image forming apparatus divides an original image into multiple areas depending on the magnification of copy and produces enlarged copies of the divided areas on sheets of copy paper sequentially, thereby obtaining a enlarged copy of the original larger than the paper size. For each divided area, copy paper of a smallest possible size necessary to copy the entirety of the divided area is selected. The original can be divided optimally based on the original size, copy paper size and magnification, or can be divided by excluding a specified region from the original.

Image forming apparatus

An image processing apparatus capable of contracting or enlarging an original image includes a variable scale magnification processing unit for magnifying the original image in accordance with a magnification m, and a digital filter for correcting an image quality. Since weighting matrixes h1-h5 of the digital filter are varied depending on magnification m, a deterioration in image quality can be prevented irrespectively of magnifications.

Image processing apparatus capable of preventing deterioration in image

An image reading and processing apparatus scans an image-carrying medium along a predetermined path and, during each cycle of line scanning, image data is produced from a line of pixels and is stored into image data memories while data-write and date-read address signals are generated by first and second address generators and are supplied independently of each other to the image data memories. A second address generator is operative to supply data-read address signals to the image data memories at a timing regulated on the basis of a signal indicative of a magnification/reduction ratio at which an image on an image-carrying medium is to be reproduced. An attribute data storage memory has a plurality of memory spaces respectively corresponding to a plurality of scanning areas, each memory space storing attribute data designating the conditions in which the image is to be reproduced. The attribute data storage memory is responsive to an attribute data address signal for outputting the attribute data corresponding to the attribute data address signals, wherein the image data output from the image data memory is processed on the basis of the attribute data output from the attribute data storage memory in all magnification/reduction ratios.

Image reading and processing apparatus

A digital color copying machine comprising a test mode is disclosed. In the test mode, image data corresponding to a partial area of an original document indicated is stored in a RAM, and thereafter, the image data stored in the RAM is read out repeatedly, and plural test images for which the color correction is made with different color balances respectively are formed as mosaic monitor images on a recording medium. Then, one of plural test images is selected, and a copy of document having a color balance of the selected test image is produced. The state of the selected color balance is displayed on a display section.

Digital color copying machine comprising a test mode for making a color

A digital color copying machine comprising a memory for storing a multi-level image signal or a binary image signal is disclosed. In a superimpose mode of the copying machine, after an image signal of a first document image stored in the memory is read out, the first document image is superimposed on a second document image on a copying paper.

Digital color copying machine

A digital color copying machine comprising a test mode is disclosed. In the test mode, image data corresponding to a partial area of an original document indicated is stored in a RAM, and thereafter, the image data stored in the RAM is read out repeatedly, and plural test images for which the color correction is made with different color tones respectively are formed as a mosaic monitor image on a recording medium. Then, one of plural test images is selected, and a copy of document having a color tone of the selected test image is produced. The test mode is canceled if a test image has not been selected during a predetermined time period.

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Osaka, Japan

Shigeru Moriya