Abstract: A shading correction circuit of the present invention includes an image pickup device having photo detectors arranged on its receptive surface, and a shading correction part for performing shading correction on an output signal of the image pickup device. The image pickup device has an effective pixel area and an upper optical black part. The shading correction part has a correction coefficient generating part and a correction processing part. The correction coefficient generating part thereof extracts shading variation according to an output of the upper optical black part, and generates a correction coefficient for the shading variation. The correction processing part thereof performs shading correction on an image signal by using the correction coefficient generated by the correction coefficient generating part.

Abstract: A computer-implemented method for preventing strike-through and show-through in printing comprises grouping pages of an electronic document into at least one page pair, identifying an area of high ink density in a page of the page pair, adjusting ink density of an image object related to the area of high ink density to ameliorate the area of high ink density, and sending the electronic document to an output device.

Abstract: Techniques and tools for analyzing and adjusting the exposure of digital images are described. For example, a computer processes a digital image by analyzing exposure data, assigning an image classification (e.g., StretchNeeded, UnderExposed, OverExposed, or Normal) based on the analysis, and selecting an exposure compensation technique (e.g., histogram stretch, positive gamma curve, negative gamma curve, or no adjustment) based on the image classification. The exposure data can be luminance values for pixels in the digital image represented in a histogram. The computer can produce transform data comprising a transformation of the exposure data according to the selected exposure compensation technique. The computer can store transform data in a look-up table and can store the look-up table in the digital image file. The described techniques and tools can be implemented as a feature of an operating system environment and can be activated responsive to user action via a user interface.

Abstract: An image scanner includes a transparent plate, a scanning device, a driving device, a positioning member, a light absorbing portion and a white reference portion. The transparent plate has an original placing surface. The scanning device irradiates an original with light by means of a light source and scans reflected light from the original. The driving device reciprocates the scanning device along the transparent plate. The positioning member positions the original placed on the original placing surface of the transparent plate. The light absorbing portion, which is disposed on the original placing surface side of the positioning member and at substantially a central portion of the positioning member in moving directions of the scanning device, absorbs ambient light entering to the original placing surface side of the positioning member through the transparent plate. The white reference portion is provided to the original placing surface side of the positioning member.

Abstract: An image reading apparatus includes a reading unit having contact glass through which an image is read from a document, backup glass located opposite the contact glass of the reading unit so as to form a conveying path between the backup glass and the contact glass through which the document is passed, a white member located on a rear surface side of the backup glass which is different from a contact glass side of the backup glass, a support plate that allows the white member to pivot between a position where the white member stands opposite the contact glass via the backup glass and a retract position where the white member is retracted from the position where the white member stands opposite the contact glass, and a regulating member provided between the backup glass and the white member so as to create a specified gap between the white member and the rear surface of the transparent member.

Abstract: When a monochromatic mode is set, a CPU outputs a SW signal and executes a control to input an output from a monochromatic reading line sensor to a CCD signal processing section. Then, after a black level adjustment period ends and a black reference level reaches a desired value, the CPU starts reading of a black reference signal for shading correction. When a color mode is set, the CPU outputs a SW signal and executes a control to input an output from a color reading line sensor to the CCD signal processing section. After the black level adjustment period ends and the black reference level reaches a desired value, the CPU starts reading of a black reference signal for shading correction.

Abstract: An image reading device reads out an image of a document being conveyed above one main surface of a contact glass, changes a document reading position if the image has an abnormality, and gives a warning if the changed document reading position is located at a predetermined reference position. The image reading device has a setting portion for changing the reference position in accordance with the number of documents that have passed the document reading position during the time when no abnormality in images is obtained by reading the documents.

Abstract: A method for selectively optimizing a plurality of image characteristics for captured images, that includes modifying two or more one-dimensional image characteristic controls using a single loop position controller having one-dimensional control. The single loop position controller traverses useful ranges of each of the two or more one-dimensional image characteristic controls. Additionally, a user cycles through several combinations of the two or more one-dimensional image characteristic controls within a video loop; and has a means of selecting a desired image rendered according to the two or more one-dimensional image characteristic controls.

Abstract: In various embodiments of the present invention, a number n of mutually interfering signals are denoised by selecting a discrete universal denoiser method that denoises n mutually interfering signals, tuning the discrete universal denoiser to denoise the n mutually interfering signals, and denoising the n mutually interfering signals by applying the tuned discrete universal denoiser to the n mutually interfering signals.

Abstract: An image reading apparatus includes: a light source that irradiates a document; a sensor that receives reflection light reflected from the document; a reference member that is read by the sensor; and an abnormal site detection unit that detects, using first reading data acquired by reading the reference member according to a first reading condition set to the light source or the sensor and second reading data acquired by reading the reference member according to a second reading condition, which is different from the first reading condition, set to the light source or the sensor, abnormal sites in the first reading data or the second reading data.

Abstract: By reading an image of a reference plate, whether or not a likeliness that a linear abnormal image is occurred in the image of the document due to a foreign matter and the like attached on a contact glass exists is determined. In the case where there is the likeliness of occurrence of the linear abnormal image, the occurrence of the abnormal image is suppressed by changing an image reading position. At this time, a reading sensitivity is measured by reading a reference document having a single white color instead of a normal document. An adjustment data is generated according to the measurement result and stored in a memory. Then, light quantity of an exposure lamp is regulated in accordance with the document reading position by using the adjustment data.

Abstract: An image scanning apparatus and method are provided in which shading data of the image scanning apparatus is acquired when manufacturing the image scanning apparatus, which is when a white reference or the shading data is cleanest. An original document is scanned using the shading data acquired when manufacturing the image scanning apparatus and shading data of non-contaminated regions of a white reference or shading reference, thereby eliminating distortion such as white lines in an image caused by pollutants stuck to the shading reference or the white reference and improving the performance of the image scanning apparatus.

Abstract: A system that compensates for uneven lighting in a digital image of a surface. During operation, the system receives the digital image of the surface. Next, the system obtains a reference lighting map for the surface, which contains information about the lighting of the surface at the time the digital image was acquired. The system then uses the reference lighting map to compensate for uneven lighting in the digital image.

Abstract: During a sheet-through operation, for a first original, a shading operation is performed to acquire white data and a light-quantity measuring operation is performed to acquire a reference value. For subsequent originals, only the light-quantity measuring operation is performed to acquire a subsequent light quantity. If the reference value and the subsequent light quantity differ greatly, the shading operation is performed at this time point to acquire new white data. The sheet-through operation is not stopped when the shading operation is not performed and the sheet-through operation is stopped when the shading operation is performed.

Abstract: A method for enhancing an image includes generating a luminance histogram for the image; generating a derivative histogram by taking a first derivative of the luminance histogram; searching for a plurality of black peaks and searching for a plurality of white peaks using the derivative histogram; and performing luminance scaling of the image between one black peak of the plurality of black peaks and one white peak of the plurality of white peaks.

Abstract: An image processing apparatus for obtaining image information by detecting, as an image signal, an electrical signal corresponding to a reflectance or transmittance of an original, including: an A/D converting circuit for converting an analog signal outputted from a photoelectric conversion element into an n-bit digital signal; and a shading correcting circuit for correcting an output characteristic of the photoelectric conversion element, high m bits of the n-bit digital signal being set as effective bits when white shading data is obtained, low m bits of the n-bit digital signal being set as effective bits when black shading data is obtained, bits being added as low bits to the m-bit white shading data, bits being added as high bits to the black shading data, shading calculation being performed. In the image processing apparatus, a capacity of a shading memory can be suppressed without reduction in quantifying resolution of the black shading data.

Abstract: The invention relates to an apparatus and method for image processing, which can prevent saturation of a high-density image to read the image in which gradation skip is not generated in reading information on a document. Image density is detected based on an image signal, and sensitivity characteristics of the image signal is switched based on the detected result.

Abstract: In a set of non-reference gamma characteristics corresponding to a density adjustment value, a first region has first characteristics for converting input values to the maximum output value. A second region has second characteristics for converting input values to the minimum output value. A third region defined between the first and second regions has third characteristics for converting input values to intermediate output values. The third characteristics defines a monotonous curve that changes monotonously with respect to change in the amount of the input value. The amount of at least one of the first region and the second region is different from the amount of the corresponding at least one of the first reference region and the second reference region of the reference gamma characteristics by a degree dependent on each density adjustment value.

Abstract: An image forming apparatus includes an image reading device which reads an image in accordance with a sheet-through method. The image reading device includes a reading device and a control device. The reading device is configured to include a carriage including an optical device for optically reading an image. The control device is configured to control shading correction of images on successively fed sheets by first performing the setting of the timing of starting a shading correction and the setting of the operation of the carriage, and then performing the setting of shading correction before shading correction starts during the operation of the carriage.

Abstract: A picture color tone controlling method for a printing press is disclosed wherein color tone control can be performed using an IRGB densitometer which requires a lower cost than a spectrometer. A target mixed color halftone density for each ink supplying unit width when a printing picture is divided with an ink supplying unit width of an ink supplying apparatus (6, 7) is set. Then, an actual mixed color halftone density for each ink supplying unit width of a regular printing sheet obtained by printing is measured using an IRGB densitometer (1), and the ink supplying amount is adjusted for each ink supplying unit width so that the actual mixed color halftone density may approach the target mixed color halftone density.

Abstract: The invention includes a brightness reading position control section for reading reference data of a reference plate a plurality of times for different locations by an image reader, a reading data storage section for storing the plurality of brightness reading data on the basis of each charge coupled device element, and a correction value computing section for performing computations on the plurality of brightness reading data in order to compute correction reference data for performing shading correction of an image data derived from an original. The invention makes it possible to prevent variations in the correction reference data that occur due to dust sticking onto or scratches formed in the reference plate.

Abstract: A method for enhancing an image includes applying an auto-level transformation to an original image to form a first image, applying an auto-contrast transformation to the original image to form a second image, and applying an auto-brightness transformation to the original image to form a third image. The method further includes applying a color cast correction to the first, the second, and the third images to generate a first group of images, applying a gamma correction to the first group of images to generate a second group of images, applying a sharpening correction to the second group of images to generate a third group of images, and presenting the third group of images to a user to select a final result.

Abstract: An image reading apparatus including: an image sensor unit having a light source that irradiates light onto an original document transferred to a predetermined image reading position, and a light receiving element that receives reflected light of the light; a white reference member for shading correction, provided so as to oppose the image sensor unit across a transferring path for the original document; an actuator that adjusts a position or an angle of the white reference member; and a control device that sets a position or angle of the white reference member and controls the actuator so as to adjust the white reference member to the set position or to the set angle, so that light reflected from the white reference member is received on the light receiving element when correcting shading, and so that the reflected light is not received on the light receiving element when reading an image.

Abstract: A method for generating a tonal response curve for a scanner includes (a) directing light from the scanner to a calibration target having a single uniform neutral tone; (b) measuring with the scanner an amount of incident light reflected from the calibration target to obtain a simulated optical density value associated with the calibration target and the amount of incident light; (c) changing the amount of the incident light; (d) repeating acts (b) and (c) until a predetermined number of simulated optical density values are accumulated; and (e) generating the tonal response curve for the scanner by matching each of the simulated optical density values with one of a plurality of reference optical densities.

Abstract: In an image reading apparatus, the invention provides a method for detecting foreign matter which may adhere to a white reference plate, and correcting a reference value when foreign matter is detected. The method includes computing an average of read values, comparing an absolute value of difference between the computed average value and data of the next read position to a predetermined threshold, and when a determining unit determines that foreign matter adheres to the reference plate, replacing the average value used for the determination of whether or not the foreign matter adheres to the reference plate with the read data.

Abstract: An image sensing apparatus has an image sensing element for photoelectric conversion, a shutter for selectively creating a light-shielded state and non-light-shielded state for the image sensing element, a bright signal storage unit for storing a bright signal output from the image sensing element in the non-light-shielded state, a dark signal storage unit for storing a dark signal output from the image sensing element in the light-shielded state, an operation unit for subtracting the dark signal from the bright signal to obtain a signal with suppressed dark noise, and a control unit for controlling read of bright and dark signals from the image sensing element in accordance with the relationship between the exposure time of the image sensing element and the photographing time interval.

Abstract: An image processing apparatus is provided that includes a scanning unit for scanning a document to obtain scanning data and a control unit. The control unit is configured to specify a shadow region to be modified in the scanning data, execute a first adjusting operation for selecting a gray-scale level of a portion of the scanning data corresponding to the specified shadow region, and modify the scanning data according to the selected gray-scale level.

Abstract: The present invention provides an image reading apparatus including: a document feeding unit that feeds a document along a feeding path; a read-out sensor that reads out an image from the document fed by the document feeding unit without stopping the feed; a control unit that causes the read-out sensor to stay on standby in a predetermined retracted position at a distance from the feeding path when it is not necessary to read out the image of the document, and causes the read-out sensor, when it is necessary to read out the image of the document, to move to a predetermined document reading position and to read out the image from the fed document; and an output unit that outputs the image data read out by the read-out sensor.

Abstract: An image reading device of the present invention reads a reference white plate before an actual document image in order to generate shading correction data. As for the first line, an input data determining circuit unconditionally determines that input data is normal. A sum data selecting circuit selects input data if the input data is normal or selects a value stored in a white data storage if otherwise. A sum data calculating means forcibly makes data output from white sum data storage (logical) ZERO, i.e., black data and then writes the result of calculation in the above storage. As for the second and successive lines, a decision value calculating circuit calculates a noise decision value for each pixel by using the white data of a previous line stored in the white data storage. The input data determining means compares the noise decision value and input image data to thereby determine whether or not the input image data is normal.

Abstract: An apparatus for reading an image on a medium to be read using a light emitting device and a light receiving device is disclosed in which a determination is made that at least one of the light emitting device and the light receiving device malfunctions in the presence of a substantial coincidence between a consecutive number of abnormal pixels adjacent to each other and a reference value.

Abstract: A scanning apparatus includes a body, a transparent plate, a scanning module, and a color reference slice. A paper-feeding track is formed within the body, and a scanning window is formed at a side wall of the paper-feeding track. A coupling groove is formed at an edge of the scanning window. Both the transparent plate and the color reference slice have an edge being inserted into the coupling groove, such that the transparent plate covers the scanning window while the color reference slice leans against a side surface of the transparent plate facing the paper-feeding track. The scanning module is disposed within the body corresponding to the scanning window, such that a paper to be scanned and the color reference slice are located in the same plane, and the color reference slice and the paper are scanned under the same optical conditions.

Abstract: An image reading method and apparatus. A reader is mounted and reads one side of an original document being conveyed at a reading position. A contact glass includes a surface contacting the original document. A reference is disposed at a side of the contact glass opposite to the surface and movable between the reading position and a standby position. The reference includes a surface facing the reader which has a predetermined color for providing shading data used for a shading correction. A carrier moves the reference to the reading position. The reader obtains the shading data by reading the predetermined color on the surface of the reference at the reading position.

Abstract: There is provided a technique that, when shading compensation is performed in an image reading apparatus, is less prone to be influenced by a smudge or the like adhered to a document glass or a white reference plate to be read by an optical reading system, and hence is able to contribute to an improvement in the quality of read images.

Abstract: An image reading apparatus includes an abnormal pixel detection device configured to examine a value of standard white image data, which is acquired by reading a white image to be a standard for a shading correction, on a pixel-by-pixel basis, to determine whether or not pixels are abnormal, wherein a previously specified value is stored for use as the standard white image data for pixels which are determined to be abnormal by the abnormal pixel detection device. As a result, costs of the image reading apparatus can be reduced because a special memory device for memorizing the positions of abnormal pixels is not required.

Abstract: Delay circuit parts are disposed between a signal converting part and buffers. Since the capacities of delay elements provided respectively for the wiring of output wiring parts are different, time lag is generated respectively in the output timings of digital output signals outputted from the signal converting part relative to control clock signals. The output timings of the digital output signals shift so that the simultaneous switching of the digital output signals is prevented. Accordingly, EMI noise can be reduced without requiring the use of a special interface standard or the addition of shield members.

Abstract: A method for processing a digital input image data indexed to represent positions on a display such that the digital data is indicative of an intensity value for each position. The intensity value for each position is transformed to generate an enhanced value, using a mapping function which transforms the same intensity value of input data to essentially the same intensity value of output data in the luminance channel.

Abstract: There is provided an image reading apparatus that is capable increasing the detection accuracy for dust, scratches, dirt, and the like. Sixty-four lines of sampling points on a reference standard white plate are read, shading correction and averaging are carried out the read image data to suppress random noise components in the image data, the data is then stored in a sampling memory, and dust detection is carried out on the data stored in the sampling memory. Alternatively, shading correction and dust detection are carried out on image data that has been subjected to linear interpolation. It is thus possible to increase the accuracy of detection of dust, scratches, dirt, and the like while ensuring that shading correction is performed at high speed.

Abstract: A calibration mechanism of a scanner includes a second light source, a calibration element having an opening, a first light source and a scanning module. The second light source is assembled with the calibration element, and the first light source is disposed at a position opposite to the calibration element. During the shading correction, the calibration element is rotated by an angle so that the first light source illuminates on a surface of the calibration element, and the reflected light enters the scanning module. When a transmissive original is being scanned, the light of the second light source passes through the opening of the calibration element and the transmissive original, and then enters the scanning module.

Abstract: An image scanning device including: a conveyance path which conveys originals; a first scanning means and a second scanning means which are placed such that they sandwich the conveyance path; and a white reference member used for adjusting the white levels of the scanning means; wherein at least one of the first scanning means, the second scanning means and the white reference member is movable; the first scanning means and the second scanning means can scan the same surface of said white reference member since the first scanning means or the second scanning means is moved or the white reference member is moved.

Abstract: An image reading apparatus in which cross-talk noise occurring between plural reading units is reduced, an image reading method and an image reading program are provided. There are included plural reading units that respectively operates at different timings, a reference data generation unit that acquires first read data as a result of reading of a first read object, acquires an operation state of the plural reading units during the reading of the first reading object, generates reference data based on the first read data, associates the operation state with the reference data obtained in the operation state and stores them, and a correction unit that acquires second read data as a result of reading of a second read object, acquires an operation state of the plural reading units during the reading of the second reading object, acquires the reference data corresponding to the operation state, and corrects the second read data based on the reference data.

Abstract: To improve operationality in color adjustment of an image quality, colored characters, or the like of a document including one of a character image, a photographic image, and a screened halftone image of chromatic or achromatic color, the invention comprises image processing means (36) for identifying a character area, a photographic area, and a screened halftone area of a document on the basis of a first parameter and determining whether one or more of the character area, the photographic area, and the screened halftone area of the document are chromatic or achromatic on the basis of a second parameter to perform image processing according to them; operation setting means (14) for setting the first and second parameters; and control means (15) for displaying a first parameter adjustment content for use in identifying one or more of the character area, the photographic area, and the screened halftone area of the document and a second parameter adjustment content for use in determining whether one or more of t

Abstract: An image forming apparatus and a control method thereof are disclosed.

Abstract: Disclosed is an image reading apparatus which reads images in a front side and a back side of a document by passing the document through the image reading apparatus once including a first reading section to read the front side of the document, a second reading section to read the back side of the document and an image process section to calculate a first standard value for carrying out a first shading correction to the first reading section and a second standard value for carrying out a second shading correction to the second reading section, respectively, and to carry out the first shading correction to a first image data read by the first reading section based on the calculated first standard value and to carry out the second shading correction to a second image data read by the second reading section based on the calculated second standard value.

Abstract: An image forming apparatus including (a) a ? conversion unit having a ? conversion table ??i of a first one Vcont? of a designation development contrast in a case that a development contrast correction amount ?Vcont1 is a first value, and a ? conversion table ??i, different from the ? conversion table ??i, of a second one Vcont?, different from the first one Vcont?, of the designation development contrast in a case that the development contrast correction amount ?Vcont1 is a second value different from the first value, and (b) an arithmetic operation unit for calculating a ? conversion table ?Nowi of a third one VcontNow of the designation development contrast in a case that the development contrast correction amount ?Vcont1 is a third value, based on a formula: ?Nowi=??i+(??i???i)×(Vcont??VcontNow/(Vcont??Vcont?), wherein the subscript i is a value of an output density signal in the ? conversion table.

Abstract: A method and program product for real-time correction of non-functioning pixels in digital radiography, where the method comprises: receiving a list of non-functioning pixels; determining which neighboring functioning pixels are needed to correct the non-functioning pixels; organizing those neighboring functioning pixels and corresponding non-functioning pixels into a plurality of groups by a number of pixels used to perform correction; and performing correction of data from non-functioning pixels within one of the plurality of groups and subsequently performing correction of data from non-functioning pixels within another one of the plurality of groups.

Abstract: A method of calibrating image luminance values is provided. Firstly, scan N calibration charts to obtain N corresponding actual luminance values, where N is a positive integer larger than 2. Next, scan a document to obtain a scan luminance value. Then, provide N ideal luminance values corresponding to the N calibration charts. Lastly, determine a calibrated luminance value according to the N actual luminance values, the N ideal luminance values and the scan luminance value.

Abstract: An imaging device for reducing fixed pattern noise caused by dark current or the like. The imaging device (10) includes a solid state imaging device (11) and a signal processor (12). The solid state imaging device (11) includes a plurality of image cells (Ca) and generates a pixel signal having a logarithmic characteristic that is in accordance with the amount of incident light entering each image cell (Ca). The signal processor (12) includes a correction data table (33) that stores first correction data for correcting the pixel signal and a dark current error data table (34) that stores second correction data for correcting the pixel signal in a low illuminance range. The signal processor (12) has an offset correction computation circuit (31) for correcting the pixel signal based on the first correction data and generating first pixel data. Further, second correction data of the dark current error data table (34) corresponding to the first pixel data is read when necessary.

Abstract: A calibration mechanism of a scanning device including an assembly of a flexible member and a calibration strip and a limiting member is disclosed. The assembly of the flexible member and the calibration strip can travel in reciprocating motion, and the limiting member limits the distance of the vertical drift of the calibration strip. Thus, the calibration strip is confined within an anticipated position, and the accuracy and the consistency of the calibration results for an optical module of the scanner, which acquires image data of a plurality of the-scanning lines of the calibration strip, are greatly improved.

Abstract: A sheet-fed scanner capable of scanning multiple scan lines for image signal calibration includes a housing, a sheet-feeding mechanism, a first scanning module, a first actuator and a first calibration sheet. The sheet-feeding mechanism disposed in the housing feeds a document across a scan region. The first scanning module rotatably mounted in the housing scans a front side of the document fed across the scan region. The first calibration sheet is fixed in the housing and disposed in the scan region. The first actuator drives the first scanning module to rotate such that the first scanning module senses a plurality of scan lines on the first calibration sheet to obtain a first calibration standard for calibrating a first image signal of the front side of the document. Thus, it is possible to avert any flaws in image quality caused by the contaminated calibration sheet.

Abstract: Provided is an image reader including: a first reading device for reading an image on one side of a document moving on a transparent glass plate; a second reading device as a movable reading device, for reading one of an image on another side of the document moving on the transparent glass plate and an image on another side of the document remaining stationary on the transparent glass plate; and a show-through preventing member for preventing show-through of the document at a first position opposed to the first reading device, characterized in that the show-through preventing member is provided movably from the first position opposed to the first reading device to a second position in which reading of an image by the second reading device is prevented from being hindered.