Shade Correction Patents (Class 358/461)
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Patent number: 7253932Abstract: An image reading apparatus is provided which is capable of preventing abnormal lines from being generated on an image read out from an original document even if there is more or less dirt attached to a reading glass exclusively used for reading ADF original documents. In an image reading apparatus 100 of the present invention, in case of dirt adhering to a reading glass 11, when an original document 13 being sent to a document reading position PW by a transportation part 12 of an automatic document feeder 10 is being read by a scanning carriage 23 through the reading glass 11, abnormal densities appear in pixel data of positions corresponding to the dirt among the readout pixel data. However, a control part 30 of the image reading apparatus 100 nullifies the pixel data of abnormal densities, and compensates for the nullified pixel data based on their surrounding pixel data.Type: GrantFiled: December 30, 2002Date of Patent: August 7, 2007Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventor: Kazuyoshi Tsutsumi
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Patent number: 7248388Abstract: An optical scanner includes a first reference white board and a second reference white board perpendicular to two sides of a glass window that holds an object to be scanned. When the optical scanner is powered on, the optical module scans the first reference white board and the second reference white board to obtain data of image quality test and brightness variations in Y direction first, and through software compensation and correction, to obtain a normal digital image data thereby to achieve rapid preview and scanning.Type: GrantFiled: March 30, 2004Date of Patent: July 24, 2007Assignee: Lite-On Technology CorporationInventors: Ta-Yi Lee, Tung-Fu Hsieh, Hsiao-Li Kao
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Publication number: 20070165257Abstract: An image processing apparatus comprising reading means for reading document images; extracting means for extracting the characteristic amounts representing the characteristics of color information from first and second image data read from the images of first and second documents respectively; calculating means for calculating the difference between the two extracted characteristic amounts; determining means for determining the magnitude relationship between the calculated difference and a predetermined value; judging means for judging, on the basis of the result of the magnitude judgment, whether processing should be carried out for the second image data; and means for processing the second image data when it is judged that the processing should be carried out.Type: ApplicationFiled: January 18, 2007Publication date: July 19, 2007Applicant: Sharp Kabushiki KaishaInventor: Takeshi Owaku
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Patent number: 7236270Abstract: A white reference image is inputted to an image sensor with a light source lit up, and white reference data is set every effective photosensor element by inspecting the output signals of the image sensor as to the white reference image (steps S305 and S310). After the input of the white reference image, the light source is extinguished (point e in FIG. 1), a black reference image is inputted to the image sensor (step S315), and black reference data is set every effective photosensor element by inspecting the output signals of the image sensor as to the black reference image (step S320). After the light source is lit up (point f in FIG.Type: GrantFiled: September 10, 2002Date of Patent: June 26, 2007Assignee: Seiko Epson CorporationInventor: Yukio Okamura
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Patent number: 7236275Abstract: Disclosed is an image reading apparatus capable of selectively executing a flow-scan reading method in which a document is read while the document is transported in a state in which a reader is fixed at a predetermined location, and a fixed reading method in which a document is read while the reader is moved in a predetermined direction in a state in which the document is held fixed, the apparatus having a first holding member for holding a document at the predetermined location for implementation of the flow-scan reading method, and a second holding member, which has a spectral transmittance different from that of the first holding member, for holding a document for implementation of the fixed reading method. The apparatus discriminates whether the flow-scan or fixed reading method is executed and sets coefficients, which are used in at least the reader or the image processing unit, in accordance with the flow-scan or fixed reading method.Type: GrantFiled: September 9, 2002Date of Patent: June 26, 2007Assignee: Canon Kabushiki KaishaInventor: Nobumasa Fukuzawa
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Patent number: 7221808Abstract: An image processing device for emphasizing a specified luminance area of an image taken by an image sensor. The contrast between a bright portion and a dark portion of an image taken by the image sensor having a wide dynamic range of a logarithmic output characteristic can be increased by selectively emphasizing the image sensor output of any luminance area by using an output characteristic conversion table.Type: GrantFiled: June 24, 2003Date of Patent: May 22, 2007Assignee: Honda Giken Kogyo Kabushiki KaishaInventors: Sukeyuki Shinotsuka, Hideo Seki
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Patent number: 7221476Abstract: A picture image processing apparatus is provided with a hue calculating portion for calculating a hue pixel by pixel based on RGB data, a first sampling portion for sampling pixels having a hue corresponding to a skin color from the RGB data, a first characteristic quantity calculating portion for calculating a first characteristic quantity representing a characteristic of the RGB data of the pixels, a second sampling portion for sampling the pixels located in a central part of an image area, a second characteristic quantity calculating portion for calculating a second characteristic quantity representing the RGB data of the pixels sampled by the second sampling portion, a correction amount calculating portion for calculating a density correction amount using the first and second characteristic quantities, and a density correcting portion for correcting the density of the RGB data. The density of a main subject in the image can be properly corrected.Type: GrantFiled: June 5, 2002Date of Patent: May 22, 2007Assignee: Noritsu Koki Co., Ltd.Inventors: Noriyuki Nishi, Hisakazu Kuramoto, Shoichi Dedachi, Keiji Nakano
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Patent number: 7212320Abstract: An image reading device of the present invention includes a glass platen mounted on a support member. A rotary cam, a home position sensor and so forth allow the support member to move in reciprocation in a subscanning direction. When a document is conveyed along the glass platen, the glass platen is moved in the subscanning direction together with the support member. Consequently, a reading section and the reading position of the glass platen move relative to each other, obviating black stripes and other defects ascribable to contamination.Type: GrantFiled: March 23, 2001Date of Patent: May 1, 2007Assignee: Ricoh Company, Ltd.Inventor: Shinji Imoto
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Patent number: 7212312Abstract: An automatic scanner calibration method and apparatus is disclosed in which a calibrated target, such as a Kodak® gray strip, is attached to a scanning surface of a scanner. The target is thin and has a width or length of platen of a scanner. During a normal scan, the calibration target area can be ignored or scanned depending on user selection. If the strip is scanned, then the resulting information is used to calibrate the scanner automatically. Such calibration is more accurate than an older in time or preset default calibration. Another embodiment of the invention actuates a print of a printer calibration target on a printer on a scheduled basis. Thereafter, the user can take the printer calibration target and place it on the scanner and perform a calibration of a scanner/printer system.Type: GrantFiled: October 11, 2001Date of Patent: May 1, 2007Assignee: Electronics for Imaging, Inc.Inventor: Margaret Motamed
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Patent number: 7209598Abstract: An image correction method is provided. First, scan an all-white document and form a scanned image including a plurality of image pixels with each of them having a gray level value. Next, gather these gray level values statistically such that each of them has an image pixel quantity. Then the maximum gray level value and the minimum gray level value are selected and a middle gray level value is obtained accordingly. Following that, determine whether the reference gray level value is greater or smaller than the middle gray level value according to the document, select the gray level values from within the interval of (the reference gray level value±a gray level value), and weight average the selected gray level values according to these selected gray level values and their corresponding image pixel quantities to obtain a corrected gray level value.Type: GrantFiled: February 18, 2003Date of Patent: April 24, 2007Inventor: Wen-Chao Tseng
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Patent number: 7206102Abstract: An image reading apparatus includes a plurality of light-receiving elements, a lens array, and a light-shielding member. All of the light-receiving elements are arranged in a single line having an extremity. The light-shielding member covers one or more light-receiving elements disposed at the extremity.Type: GrantFiled: May 29, 2001Date of Patent: April 17, 2007Assignee: Rohm co., Ltd.Inventors: Hiroshi Fukumoto, Mitsuhiko Fukuda
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Patent number: 7206460Abstract: A method of imaging and a system therefore are provided. The imaging system includes an image forming device for generating a first image and a second image and a controller coupled to the image forming device. The controller receives the first image and the second image. In the method the controller generates an image ratio of the first image and the second image, regularizes the image ratio of the second image with respect to the first image to form a regularized image ratio and filters the image ratio to form a filtered ratio. The controller then multiplies the second image by the filtered ratio to form an adjusted image.Type: GrantFiled: November 1, 2001Date of Patent: April 17, 2007Assignee: General Electric CompanyInventor: Gopal B. Avinash
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Patent number: 7190493Abstract: A white reference image is inputted to an image sensor so as to output groups of analog data. The groups of analog data are converted by a processing unit into those groups of digital data the number of which is smaller than that of photosensor elements of the image sensor. The lowest density value of the groups or digital data is inspected, an operating environment is set so that the lowest density value of the groups of digital data may become a density value within a predetermined range. An optical system, a drive unit and the processing unit are controlled under the operating environment so as to output from the processing unit, image data which express a subject image inputted to the image sensor.Type: GrantFiled: September 10, 2002Date of Patent: March 13, 2007Assignee: Seiko Epson CorporationInventors: Yoichiro Maki, Noriyuki Noda, Takeshi Aoki
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Patent number: 7181091Abstract: Images having been subjected to image processing optimal for each user or each output device are obtained. Correction function calculation means calculates correction functions for correcting image data sets for each user ID or for each device ID, and correction function storing means stores the calculated correction functions. When the image processing is carried out on the image data sets, the correction functions corresponding to the user ID or the device ID added to the image data sets are searched for and correction parameter calculation means calculates correction parameters based on the correction functions. The image processing is then carried out on the image data sets according to the correction parameters to generate corrected image data sets.Type: GrantFiled: March 15, 2002Date of Patent: February 20, 2007Assignee: Fuji Photo Film Co., Ltd.Inventor: Akira Yoda
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Patent number: 7170643Abstract: In an image reading apparatus having a light source for illuminating a document, an image sensing element for outputting an electrical signal in accordance with an input light quantity, a first reference member, and a second reference member, shading correction data is acquired. A time since the light source is turned on is measured, and when the measured time does not reach a predetermined time, shading correction data is acquired by a first method using the first reference member. When the predetermined time has elapsed, shading correction data is acquired by a second method using the second reference member.Type: GrantFiled: January 25, 2001Date of Patent: January 30, 2007Assignee: Canon Kabushiki KaishaInventors: Noriaki Matsui, Nobuo Matsuoka, Toshio Hayashi, Junichi Kishimoto, Katsuhiro Ishido, Satoru Kijima
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Patent number: 7161712Abstract: An apparatus for forming an image includes a photosensitive body, an optical write unit which scans a light beam along a main scan path on a photosensitive body to create a latent image thereon, the light beam having power levels corresponding to multi-level image data, and a shading correction unit which corrects shading along the main scan path by making adjustment to the multi-level image data along the main scan path, and changes the adjustment on a condition-specific basis.Type: GrantFiled: April 3, 2002Date of Patent: January 9, 2007Assignee: Ricoh Company, Ltd.Inventors: Takayuki Maruta, Minori Uchida
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Patent number: 7161626Abstract: A CCD photoelectrically converts image information obtained from optically reading an original image, line by line, and outputs an image signal. Several of the photoelectric sensors of a CCD of the CCD portion form an optical black portion. A black shading correcting portion corrects the image signal using a black reference level. The black reference level is obtained from the optical black portion of the CCD for each line during an operation of the reading of the original image. The black reference level used by said black shading correcting portion for each line is obtained using black reference values, each of the black reference values being data of the optical black portion for a respective one of a plurality of lines.Type: GrantFiled: October 1, 1999Date of Patent: January 9, 2007Assignee: Ricoh Company, Ltd.Inventor: Wataru Nara
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Patent number: 7149002Abstract: A scanner includes a transparent scanning window; a housing, the housing including a first side supporting the scanning window and a second side opposite the first side; a scanning array movable in the housing relative to the scanning window along a scanning path, the scanning array generally facing the first side; a light source movable with the scanning array, the light source generally facing the first side; and a calibration target supported by the housing within the scanning path, the calibration target generally facing the second side.Type: GrantFiled: December 21, 2000Date of Patent: December 12, 2006Assignee: Hewlett-Packard Development Company, L.P.Inventor: Lori Clifton
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Patent number: 7102797Abstract: In an image reading device having a sheet-through mechanism, a controller controls a stepping motor to decelerate an image reading system when the image reading system is moved to a reference white plate reading position, and controls a stepping motor drive electric current to decrease when the image reading system reads a reference white plate. When the image reading system finishes reading the reference white plate, the controller controls the stepping motor drive electric current to increase so as to rapidly decelerate the image reading system. The controller further controls the stepping motor such that a moving speed of the image reading system to an original document reading position is lower than a moving speed of the image reading system to the reference white plate reading position.Type: GrantFiled: May 21, 2002Date of Patent: September 5, 2006Assignee: Ricoh Company, Ltd.Inventor: Yoshihiro Sakai
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Patent number: 7099047Abstract: In an image scanner, an optical image is formed on a CCD image sensor through a lens unit from rays traveling through a picture frame placed in a film carrier, so image signals are picked up from the picture frame. The image signals are corrected with shading correction data that are read out from a memory in accordance with the magnification of the lens unit. The memory previously stores shading correction data for frequently used magnification steps. Shading correction data for less frequently used magnification are previously stored in a hard disc. If the lens unit is set at a magnification for which the memory does not store suitable shading correction data, the suitable shading correction data are read out from the hard disc, and written on the memory.Type: GrantFiled: March 26, 2002Date of Patent: August 29, 2006Assignee: Fuji Photo Film Co., Ltd.Inventor: Tatsuya Konagaya
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Patent number: 7054040Abstract: First and second reading modules read first and second signals in the main scanning direction of the image of a document. The scanning module includes a carriage for relatively moving the first and second reading modules and the image of the document in a sub-scanning direction to make the modules scan the image. A scanning-control-condition selecting module selects scanning control conditions of the scanning module in accordance with a plurality of read magnifications preset as read magnifications of the document by the first and second reading modules. A first setting module sets the scanning control conditions to a plurality of control conditions in accordance with the read magnification of the first reading module. A second setting module sets the scanning control conditions to a plurality of control conditions in accordance with the read magnification of the second reading module.Type: GrantFiled: December 14, 2001Date of Patent: May 30, 2006Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventors: Hirokazu Shoda, Sunao Tabata
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Patent number: 7031029Abstract: By performing preliminary scanning, a document identification unit determines whether a document is a dark document, such as a negative film, that requires excess exposure, or an ordinary document that does not require excess exposure. When it is determined that the document does not require excess exposure, an exposure time setting unit sets an exposure time for a line sensor. Then, in consonance with the designated exposure time, the line sensor initiates the reading of a black reference. Thereafter, in accordance with an excess exposure time that is designated, a black reference data preparation unit prepares black reference data. Since the black reference is read during the same period as the excess exposure time and the black reference data is prepared, the detailed tones of the dark portion of the document can be expressed, and the quality of the image can be improved.Type: GrantFiled: April 29, 2002Date of Patent: April 18, 2006Assignee: Seiko Epson CorporationInventor: Yukio Okamura
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Patent number: 6995877Abstract: In order to appropriately control consumption power in an image reading apparatus which operates based on electric power supplied from a computer via a connection cable or an external power supply, when the external power supply is connected, a read operation is executed in a normal mode; when no external power supply is connected, a read operation is executed in a power saving mode.Type: GrantFiled: April 12, 2001Date of Patent: February 7, 2006Assignee: Canon Kabushiki KaishaInventor: Nobukazu Suzuki
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Patent number: 6992800Abstract: Disclosed is an image reading apparatus for moving a document reading unit to a point below a document feeder that feeds documents, and emitting light from a light source of the document reading unit toward a feed roller of the document feeder, whereby light reflected from a document that travels between the feed roller and the light source is sensed by the document feeding unit to thereby read an image on the document.Type: GrantFiled: December 3, 2001Date of Patent: January 31, 2006Assignee: Canon Kabushiki KaishaInventors: Tsunao Honbo, Katsuhiro Ishido
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Patent number: 6989915Abstract: An image reading apparatus comprises a correcting mechanism for correcting an output signal from a reading unit in accordance with a reference level. The correcting mechanism includes a reference element for setting the reference level and a drive mechanism for rocking the reference element between a first position in which the reference element is advanced to a reading position and a second position in which the reference element is retreated from the reading position. The drive mechanism includes a rotating member that is continuously rotated in one direction. As the rotating member rotates, the reference element rocks between the first and second positions, thereby executing correction of the output signal before image information recorded on a recording medium is read.Type: GrantFiled: September 14, 2001Date of Patent: January 24, 2006Assignee: Kabushiki Kaisha ToshibaInventors: Takashi Honjo, Tomio Nagai, Toshiyasu Omata, Hideharu Ito
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Patent number: 6987576Abstract: The invention provides an image forming apparatus and an image forming method, capable of providing an image with little deterioration, even in case the image contrast has to be adjusted not for the purpose of image adjustment, such as for reducing the toner consumption amount or for preventing the leak in the charging device.Type: GrantFiled: March 5, 2001Date of Patent: January 17, 2006Assignee: Canon Kabushiki KaishaInventor: Yuji Kamiya
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Patent number: 6985637Abstract: A method for deriving enhanced image processing parameters for a source digital image, comprising the steps of: a) providing a source digital image; b) generating at least three rendered digital images from the source digital image with at least one image processing parameter associated with each rendered digital image; c) displaying the rendered digital images on a display; d) selecting two or more of the rendered digital images; and e) using the image processing parameters associated with the rendered digital images to generate enhanced image processing parameters.Type: GrantFiled: November 10, 2000Date of Patent: January 10, 2006Assignee: Eastman Kodak CompanyInventor: Edward B. Gindele
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Patent number: 6982757Abstract: Disclosed is an image sensing apparatus having a function of removing a dark current noise component of an image sensor. This image sensing apparatus includes an image sensor such as a CCD, at least two noise component storage areas, a CPU for controlling an operation of writing a noise component of one frame generated by the image sensor into a noise component storage area selected from the at least two noise component storage areas, and a subtracter for correcting an object image photographed by the image sensor, on the basis of the noise component stored in one of the at least two noise component storage areas.Type: GrantFiled: July 11, 2001Date of Patent: January 3, 2006Assignee: Canon Kabushiki KaishaInventor: Motoi Tariki
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Patent number: 6980332Abstract: A system and method that provided for preview scanning a document and generating a preview scan image, determining a document type based on the preview scan image, mapping the document type to a predetermined workflow, scanning the document to capture an image of the document, and executing the workflow.Type: GrantFiled: June 26, 2001Date of Patent: December 27, 2005Assignee: Hewlett-Packard Development Company, L.P.Inventor: Steven J. Simske
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Patent number: 6975433Abstract: An image information reading apparatus that can obtain high quality images without an effect of noise and a photographing condition or the like is realized even in the case where a low-bit A/D converter is used. The apparatus comprises control means for switching between pre-reading to main reading, characteristic determination means for determining, by analyzing an electric signal obtained by the pre-reading, a normalization processing characteristic used in normalization processing on an electric signal obtained by the main reading, and normalization processing means for carrying out the normalization processing on the electric signal in the main reading according to the determined normalization processing characteristic. The characteristic determination means analyzes image data by using a cumulative histogram of pre-reading data, and determines the normalization processing characteristic so that an image represented by the image data has adequate density and contrast.Type: GrantFiled: April 2, 2001Date of Patent: December 13, 2005Assignee: Fuji Photo Film Co., Ltd.Inventor: Toshitaka Agano
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Patent number: 6963430Abstract: An image reading apparatus which enables a reduction of FCOT by omitting a home position search and a shading compensation after an input of a reading instruction for a succeeding original when reading different originals successively.Type: GrantFiled: July 23, 2001Date of Patent: November 8, 2005Assignee: Canon Kabushiki KaishaInventor: Noriaki Matsui
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Patent number: 6961151Abstract: An image reading-out apparatus including a background level detecting circuit, an analog-to-digital converter, and a black-shading compensation circuit. The background level detecting circuit is configured to detect the background level of the original document from the image data. The analog-to-digital converter is configured to remove an influence due to the color of the background on the original document from the image data and configured to perform the analog-to-digital conversion of the image data in accordance with the detected background level. The black-shading compensation circuit is configured to perform black-shading compensation of the image data after the analog-to-digital conversion.Type: GrantFiled: September 14, 2000Date of Patent: November 1, 2005Assignee: Ricoh Company, Ltd.Inventor: Wataru Nara
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Patent number: 6959157Abstract: Disclosed are a shading correction method for a sensor capable of accurately detecting color tint of a toner patch without using any white-color reference to execute shading correction in the sensor, a shading correction apparatus for a sensor, and a color image forming apparatus. In the shading correction, light reflected by a rich K toner patch formed on a transferring material is detected, a shading correction value for the sensor is calculated based on detected data, and correction is executed using the shading correction value during operation for detecting a toner patch for color stabilization.Type: GrantFiled: August 19, 2003Date of Patent: October 25, 2005Assignee: Canon Kabushiki KaishaInventor: Toshiki Nakayama
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Patent number: 6958834Abstract: An image reading device includes a light irradiation device that moves and scans a document while irradiating the light on the document table, a color CCD sensor which reads the reflecting light of the light from the light irradiating device and photoelectric converts it into plural color signals, and a correction device which executes the shading correction of plural color signals that are photoelectric converted by the color CCD sensor and at the same time, executes the color balance correction and the stray light correction. Further, at the same time with the shading correction executed using white document data comprising R, G, B signals of a white document in color equipment to the shading correction plate that are read and photoelectric converted by the color CCD sensor as desired values for the shading correction, this image reading device executes the color balance correction and the stray light correction.Type: GrantFiled: July 11, 2000Date of Patent: October 25, 2005Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki KaishaInventor: Naoaki Ide
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Patent number: 6947187Abstract: An apparatus and method for calibrating a scanner connected to a document feeder are provided. In one embodiment, the apparatus includes a calibration strip attached to a rotatable wheel assembly disposed within the document feeder. A cam is provided to rotate the wheel assembly and expose the calibration strip to the field of view of a head assembly of the scanner for calibration. The cam is configured to then rotate the wheel assembly in the opposite direction, so that the calibration strip is no longer exposed to the head assembly. A cleaning blade may be provided to wipe the calibration strip as it is moved to its non-exposed position.Type: GrantFiled: May 24, 2001Date of Patent: September 20, 2005Assignee: Hewlett-Packard Development Company, L.P.Inventors: Paul K. Mui, Eric L. Andersen, Russell A. Mendenhall
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Patent number: 6944353Abstract: An image processing system of the present invention comprises an image inputting portion 1 for inputting image data, a ground-level detecting portion 3 for detecting a ground level of the input image data, a pasted-manuscript deciding portion 4 for deciding whether or not the image data is a pasted manuscript, based on a user's indication or the ground level detected by the ground-level detecting portion 3, a ground-level adjusting portion 5 for adjusting the ground level in response to a distribution of the ground level detected by the ground-level detecting portion 3 if the image data is decided as the pasted manuscript, and a ground removal processing portion 6 for removing a ground of the image data at the ground level adjusted by the ground-level adjusting portion 5.Type: GrantFiled: October 3, 2001Date of Patent: September 13, 2005Assignee: Fuji Xerox Co., Ltd.Inventor: Yoichi Matsuda
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Patent number: 6937777Abstract: This invention has as its object to eliminate sensitivity nonuniformity on the plane of an image sensing element irrespective of exchange of a lens. To achieve this object, in an image sensing apparatus which has an image sensing element and can exchange a lens, a memory stores shading correction coefficients respectively corresponding to pixels in a two-dimensional matrix on the plane of the image sensing element, and a correction device makes a correction calculation of pixel data read out from each pixel of the image sensing element by extracting the shading correction coefficient associated with the corresponding pixel from those stored in the memory.Type: GrantFiled: January 15, 2002Date of Patent: August 30, 2005Assignee: Canon Kabushiki KaishaInventor: Yusuke Shirakawa
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Patent number: 6922263Abstract: In an image reading apparatus according to the present invention, a black reference plate used for shading correction includes a light shielding plate. When the light shielding plate shields an optical path leading to a CCD sensor, the light emitted from an illumination device is prevented from falling on the CCD sensor.Type: GrantFiled: October 1, 2001Date of Patent: July 26, 2005Assignees: Kabushiki Kaisha Toshiba, Toshiba TEC Kabushiki KaishaInventor: Toshihiro Sone
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Patent number: 6922486Abstract: The invention relates to a process of shadow identification in a digital image. The digital image comprises a set of image points that can be located in a plane of the image, with each image point being associated with a color and brightness. The color is defined by chromatic components that can be located in the color space of an acquisition system, and the brightness is determinable from the chromatic components. According to the process of the present invention, for each image point, the brightness is determined; color standardization is carried out, leading to standardized chromatic components r, g, b; a chromatic brightness is determined from the standardized chromatic components r, g, b; and the chromatic brightness is compared with the brightness, to identify the presence of a shadow on the relevant image point.Type: GrantFiled: June 27, 2002Date of Patent: July 26, 2005Assignee: Eastman Kodak CompanyInventor: Valery J. Risson
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Patent number: 6920251Abstract: A peak value of readings of a reference plate is calculated by a peak value calculation means. The peak value is stored by a storage means. An average value of the readings of the reference plate is calculated by an average value calculation means. Difference data between the peak value and the average value is calculated by a difference data calculation means. A variable correction coefficient is set by a correction coefficient setting means through use of the difference data and the peak value as shading correction reference data. Readings of an document image is corrected by a correction means through use of the correction coefficient. Thereby, dispersion of document image readings in shading correction is decreased.Type: GrantFiled: July 10, 2001Date of Patent: July 19, 2005Assignee: Minolta Co., Ltd.Inventor: Hideyuki Toriyama
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Patent number: 6917451Abstract: An image reading apparatus includes a light transmitting member opposed to an original, a reading device for reading the original image through the light transmitting member, and a standard portion which is read by the reading device to perform shading compensation, wherein the standard portion is provided on the opposite side of the original with respect to the light transmitting member.Type: GrantFiled: June 7, 2001Date of Patent: July 12, 2005Assignee: Canon Kabushiki KaishaInventors: Tsuyoshi Waragai, Yasuyoshi Hayakawa, Masayoshi Fukatsu
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Patent number: 6914628Abstract: Conventionally, in image processing using a smoothing filter, the large amount of calculation for 25× the number of pixels takes much processing time. A computer 21 as the nucleus of image processing determines whether or not a pixel of interest is a color blur pixel, based on the intensity of a low-density element color, at steps S130 and S140. If the pixel is a color blur pixel, the computer 21 determines whether or not the color blur pixel is an edge pixel at step S150. If the pixel is not an edge pixel, the computer 21 uses a smoothing filter at step S152, while if the pixel is an edge pixel, the computer 21 uses a median filter at step S154, in image processing to reduce the color blur. This reduces the amount of calculation and realizes high-speed image processing.Type: GrantFiled: November 23, 1998Date of Patent: July 5, 2005Assignee: Seiko Epson CorporationInventors: Naoki Kuwata, Yoshihiro Nakami
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Patent number: 6911989Abstract: Digital circuitry for imparting halftone to that portion of a video image over which an on-screen-display (OSD) window is superimposed.Type: GrantFiled: July 18, 2003Date of Patent: June 28, 2005Assignee: National Semiconductor CorporationInventor: Peyman Hojabri
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Patent number: 6901164Abstract: An automated method of improving digital color images at high speed, which supports pipe-lining and has very little memory requirements, and is therefore specially suitable for on-the-fly processing of real time video, as well as for processing of large batches of images without the need of human intervention. The method includes a novel dynamic range adaptation scheme that operates on the norm of the image, which is suitable as is for gray-scale images. For, color images, a simple color reconstruction stage is added that maintains optimal color fidelity.Type: GrantFiled: April 11, 2001Date of Patent: May 31, 2005Assignee: Trusight Ltd.Inventor: Moredechai Sheffer
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Patent number: 6892945Abstract: An image reading apparatus for reading a document has an image sensor unit, which is moved along a platen glass in a sub-scanning direction, mounting an LED, a light guide and a sensor. A white reference panel for use of shading correction is provided on the platen glass on the side thereof opposite the image sensor unit. Light shield plates are provided on the platen glass on the side facing the image sensor unit along both sides of the white reference panel.Type: GrantFiled: October 23, 2002Date of Patent: May 17, 2005Assignee: Canon Kabushiki KaishaInventor: Kazuo Shishido
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Patent number: 6891648Abstract: An image-reading device is provided. The image-reading device comprises a photoelectric converting element reading a first image from a subject copy, a reference-white member functioning as a reference white used in a white-shading correction, reading means for reading a second image from a constant range on a surface of the reference-white member by using the photoelectric converting element, averaging means for dividing image data of the second image into a plurality of blocks in a sub-scanning direction so that each of the blocks includes a plurality of lines and obtaining average values of image data of the lines in the blocks respectively, peak-value determining means for obtaining a peak value of the average values, and white-shading correcting means for performing the white-shading correction to image data of the first image by using the peak value as white-shading data.Type: GrantFiled: August 29, 2001Date of Patent: May 10, 2005Assignee: Ricoh Company, Ltd.Inventors: Yoshikazu Inoue, Wataru Nara, Yasuyuki Nomizu, Hiroyuki Kawamoto, Hiroshi Fukano, Motoya Sano, Hiroshi Kubo, Hitoshi Hattori
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Patent number: 6879730Abstract: There is provided a sensitivity correction method in which shading can be eliminated regardless of a type of a photographic film. A film carrier is moved to a position where a vertical direction center of a first correction plate, having a uniform spectral reflection characteristic, is coincident with an optical axis. Transmitted light from the first correction plate is detected by a linear CCD, and shading data for a positive is acquired. The film carrier is moved to a position where a vertical direction center of a second correction plate, having a spectral reflection characteristic substantially identical to that of a base portion of a negative film, is coincident with the optical axis. Transmitted light from the second correction plate is detected by the linear CCD, and shading data for a negative is obtained.Type: GrantFiled: April 12, 2000Date of Patent: April 12, 2005Assignee: Fuji Photo Film Co., Ltd.Inventor: Takashi Hirakawa
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Patent number: 6853815Abstract: In a color image forming apparatus, a color toner patch for controlling density or chromaticity may be detected by a color sensor and fed back to process conditions so as to control density or chromaticity of a final output image. However, a white reference board for proofreading sensor output is expensive, and may have paper powder, toner or ink scattered thereon to become no longer usable as a reference board. The present invention provides a color identification method and a color image forming apparatus exploitable for density or chromaticity control by using a color sensor without using the reference board.Type: GrantFiled: September 6, 2002Date of Patent: February 8, 2005Assignee: Canon Kabushiki KaishaInventors: Hiroki Tezuka, Yoichiro Maebashi
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Publication number: 20040263915Abstract: An image scanning method in which image data acquired from a scan object illuminated by a light source is compensated using shading compensation factors obtained by performing a dummy scan on a white sheet illuminated by the light source. The image scanning method includes obtaining a first luminance value of the light source during the dummy scan, obtaining a second luminance value of the light source during an image scan, and updating the shading compensation factors based on the first luminance value and the second luminance value.Type: ApplicationFiled: June 25, 2004Publication date: December 30, 2004Applicant: Samsung Electronics Co., Ltd.Inventor: Bok-ki Park
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Patent number: 6833862Abstract: A method and apparatus for constructing an inexpensive camera with vignetting correction in the camera electronic hardware. The hardware is programmable through the use of a register storing a constant value corresponding to the amount of vignetting of a particular lens used in the camera. The register value is provided to a correction circuit which implements an algorithm that corrects for the amount of vignetting of pixels depending upon the pixel position.Type: GrantFiled: June 30, 1999Date of Patent: December 21, 2004Assignee: Logitech, Inc.Inventor: Wei Li