Abstract: A color image processing apparatus includes: a minimum value selection unit that selects a minimum value of an input gray level values; a first calculation unit that calculates a generation amount of black; a second calculation unit that calculates an UCR amount which is a value relevant to the minimum value; a third calculation unit that outputs a correction coefficient value which is a value relevant to the minimum value; a subtraction unit that subtracts the UCR amount from each of the input gray level values to generate output; a multiplication unit that multiply the output of the subtraction unit by the correction coefficient value; a significant bit selection unit that selects a significant bit of a multiplication result; and a gray level correction unit that makes a gray level correction to the generation amount of black and the output of the multiplication unit.

Abstract: The present invention provides a printing method including: (A) converting a tone value indicating a tone of a certain color to a first light tone value indicating a tone of a light color using a predetermined number of tones, and a first dark tone value indicating a tone of a dark color using a predetermined number of tones; (B) converting the first light tone value to a second light tone value indicating a tone of the light color with a smaller number of tones than the predetermined number of tones, based on a table for the light color; (C) converting the first dark tone value to a second tone value indicating a tone of the dark color with a smaller number of tones than the predetermined number of tones, based on a table for the dark color other than the table for the light color; (D) ejecting a light ink based on the second light tone value to form a light dot in the light ink on a medium, ejecting a dark ink based on the second dark tone value to form a dark dot in the dark ink on the medium, and expressi

Abstract: A gradation image forming apparatus comprises a gradation data generation section. The gradation data generation section generates gradation data in each pixel of a gradation image based on at least one table of a reference color number corresponding to a pixel value of a reference color which is a start color of the gradation image, at least one table of a difference number corresponding to a difference in pixel values between adjacent pixels in the gradation image, and a pixel value of each pixel of the gradation image.

Abstract: An image forming apparatus includes: an image forming unit for forming a correcting image for correcting gradations of an output image, on a bearing body; a sensor for measuring reflected light quantity of the correcting image formed on the bearing body; a gradation correcting unit for correcting the gradations of the output image, based on a measurement result of the measured reflected light quantity of the correcting image; and a timing correcting unit for detecting a shift of measurement timing, based on the measurement result by the sensor, and for correcting the detected shift of the measurement timing.

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: A printed tone control method for adjusting a printed color tone by comparing image data serving as a reference and image data obtained by reading an image from a print actually made by a printing machine. The method includes a representative point setting step for setting a representative point for use in control of the color tone based on image data, an alternative representative point setting step for setting an alternative representative point that satisfies a predetermined condition when a point inappropriate for tone measurement is selected as the representative point, and a tone adjusting step for adjusting the color tone by using the alternative representative point.

Abstract: When an output image is observed, an image processing apparatus by which image observation can be performed always in a satisfactory state irrespective of its observation environment and a change of a human's visual characteristic is provided. In this image processing apparatus, a first output unit outputs the target image in a first gradation reproduction range, and a second output unit outputs the target image output by the first output unit in a second gradation reproduction range. At this time, a correction unit performs a correction process, i.e., gradation conversion process, to the target image output by the second output unit, on the basis of information concerning the environment for observing the output result of the target image by the second output unit.

Abstract: An image processing method comprises an extracting process of extracting a characteristic amount of an input image, a generating process of generating a high frequency component of the input image, a gradation converting process of converting a gradation of the input image on the basis of the characteristic amount, and an adding process of adding the high frequency component to the input image whose gradation has been converted.

Abstract: This invention is directed to an image forming apparatus which forms a color image on the basis of image information and includes an image forming unit which forms a color reference image on an image forming member on the basis of reference image information for color correction, a colorimetric unit which measures the color of the color reference image formed by the image forming unit and outputs color information, an image processing unit which generates a gray level correction table on the basis of the color information output from the colorimetric unit, and a control unit which corrects the image information on the basis of the gray level correction table generated by the image processing unit and controls the image forming unit so as to form a color image on the image forming member on the basis of the corrected image information, and an image forming method using the image forming apparatus.

Abstract: A three-dimensional halftone screen is provided that is suited for multilevel printing. The three-dimensional halftone screen includes a plurality of planes each corresponding to one or more input intensity levels of an input RIPped pixel. Within the planes are screen dots, each associated with one or more output exposure intensity values representing an intensity of an exposure dot corresponding to the input RIPped pixel.

Abstract: An image forming system includes an information processing apparatus and an image forming apparatus. The information processing apparatus performs image generation, color conversion, and extraction of image characteristics to generate compressed data. The image forming apparatus decompresses the compressed data and determines a writing address into an image data storing unit on the basis of an amount of shift to convert the density of the image data in fractional pixel units.

Abstract: An image density discrimination chart is used to discriminate a density of a test image printed by an image forming apparatus. The chart includes an exposing portion for exposing the test image when the chart is overlaid relative to a printed recording material, a first comparison image having an upper limit level of a latitude, permitted by the image forming apparatus, for image density of the test image, and a second comparison image having a lower limit level of a latitude, permitted by the image forming apparatus, for image density of the test image.

Abstract: A printing apparatus is adapted to receive print data specifying a color of an object to be printed with RGB values and specifying a type of the object as one of a text object, a graphic object and an image object. A print processor is operable to generate black image data from a set of the print data for one page, such that a black density value for one color of at least the text object is made greater than a black density value for the one color of the image object. A print engine is operable to perform monochrome printing with black toner in accordance with the black image data.

Abstract: An image data processing method and apparatus for performing image correction processes for a restored image data file obtained from a JPEG-compressed image data file which may prevent block distortions and provide a high quality image. A JPEG-compressed data file is read from the storage medium by the reading section, which is restored at the restoring section. The restored data is then split into a low-frequency component and a high-frequency component at the splitting section. The low-frequency component is subjected to the white balance, density, and gradation adjustments at the first image correction processing section and combined with the high-frequency component at the combining section to obtain a combined image data. The combined image data is then subjected to the sharpness adjustment at the sharpness adjusting section, which is outputted from the output section to a printer and reproduced as a printed image.

Abstract: An image processing apparatus includes a receiving unit that receives a display request for displaying a preview image of gradation-processed image data, and a preview magnification indicative of a display magnification of the preview image. An image processing unit performs a first magnification-altering process on the gradation-processed image data performs the gradation process based on the image quality mode if the preview magnification is lower than a present magnification and the gradation process based on the image quality mode is such that the gradation-processed image data does not express halftone, as well as if the preview magnification is higher than the present magnification thereby obtaining processed image data. A display unit creates and displays the preview image based on the processed image data.

Abstract: When setting a color tone during editing of an image, processes such as the following are performed. First, there is displayed a tone setting screen 200 that includes a tone specifying portion 210 for substantially specifying a plurality of color tone parameters that specify the tone of an image; and a sample image display area 220 for displaying a color sample image. Next, the plurality of color tone parameters are specified through the tone specifying portion 210. Then, the tone of the color sample image is adjusted with reference to the specified plurality of color tone parameters. Then, the plurality of color tone parameters are confirmed.

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 analysis unit analyzes an image on which AE processing has been performed and obtains a coefficient for obtaining a gradient of a compression table for compressing a dynamic range of the image. A compression table creation unit creates a compression table. A correction amount calculation unit judges whether the gradient of the compression table is larger than a predetermined threshold value. If the judgment is YES, loss of fine texture in the image by dynamic range compression is significant. Therefore, the correction amount calculation unit calculates a correction amount by using an unsharp image of the image. If the judgment is NO, loss of fine texture in the image is insignificant, the correction amount calculation unit calculates the correction amount by using the image. A compression processing unit compresses the dynamic range of the image by the correction amount and obtains a processed image data set.

Abstract: A color reduction processing apparatus and method that is simple to configure and adjust produces two-color print image data reflecting the impression of the original full-color image. Each pixel in a full-color image is converted to binarized principal and secondary color print data by principal and secondary color processors respectively using respective threshold value matrices. The threshold values of these matrices, which are calculated from a reference threshold value matrix stored in memory, can be adjusted, via adjustment values, to control the overall density of the principal and secondary colors. The adjustment values can be set in a matrix configuration unit. The binarized principal and secondary color print data can also be further corrected by correction and/or filtering operations performed by a correction processor.

Abstract: A printing method for printing an image on a medium according to the present invention includes the following steps: printing a correction pattern based on a first gradation value by ejecting ink from a plurality of nozzles moving in a predetermined movement direction and forming a plurality of dot lines in an intersecting direction that intersects the movement direction; obtaining, for each dot line, first information corresponding to the first gradation value by measuring a darkness of the correction pattern dot line by dot line; and printing an image constituted by a plurality of corrected dot lines on the medium by correcting each dot line in accordance with the first information and second information corresponding to a second gradation value that is different from the first gradation value.

Abstract: After binarization is performed, the adjacency relationship of connection fields is analyzed from a labeled input image on the basis of the characteristics of the structure of a barcode, thereby extracting a barcode field. A unit width, which is to be used as the module width of the barcode, is determined in accordance with the widths of the connection fields of black pixels in the extracted barcode field. Based on the arrangement of the magnification of the unit width, the barcode is recognized by collating a prescribed barcode pattern with the input width pattern. In the aforementioned collation, the influence of noises, for example, can be reduced by setting an allowable range for the collation of the widths in each magnification, and the barcode can be recognized in an improved precision even in a low-resolution image photographed using a small image sensor built in a mobile terminal.

Abstract: An image input/output system obtains a print-job that includes printing-mode information and print-data, and analyzes the printing-mode information to determine whether the output mode of the print-data is a high-contrast output mode or a low-contrast output mode. According to the determined output mode, the image-processing device generates image data by calculating the color-space conversion of the print-data at a high bit-depth if the output mode is high-contrast, or at a low bit-depth if the output mode is low-contrast, thereby achieving output with high reproducibility in a high-contrast output mode, and high-speed output in a low-contrast output mode.

Abstract: The gray axis is adjusted such that an optimal representation can be achieved for low saturation colors close to the gray axis. A test pattern including a plurality of images, which have different color tones is printed, and a user selects a most desirable image. The gray axis of an image recording system is adjusted depending on which image is selected. Each of the plurality of images of the test pattern is a photographic color image represented mainly by low saturation colors close to achromatic colors along the gray axis. In accordance with the selected image, the gradation adjustment is performed for each ink color of the image recording system thereby adjusting the gray axis and the tone of colors close to the gray axis.

Abstract: Aspects of the invention relate to a method of processing images capable of performing natural saturation enhancement having a balance between color components with a small amount of calculation is provided. The image processing device may be arranged in an image display device or may be a device for providing display image data to the external image display device to perform the saturation enhancement of the input image data. Specifically, saturation information can be extracted from the input image data to determine a saturation enhancement amount. In addition, a color component to which the saturation enhancement is performed can be extracted from the input image data. Further, based on the determined saturation enhancement amount, the saturation enhancement for each color component can be performed. Here, for the predetermined color component, the saturation is enhanced after the saturation enhancement amount is adjusted.

Abstract: A color chart and a grayscale chart are output, and a calibration task of calculating a correction amount based on the grayscale chart by comparing a measured density value that is obtained by measuring a density of the grayscale chart and a target density value that has been found in advance, is repeated until the correction amount based on the grayscale chart is equal to or less than a first tolerance value, and at this time, as long as the correction amount based on the grayscale chart is equal to or greater than a second tolerance value that is larger than the first tolerance value, a correction amount based on the color chart is additionally calculated by comparing a measured density value that is obtained by measuring a density of the color chart and a target density value that has been found in advance, and this correction amount is used in place of the correction amount based on the grayscale chart.

Abstract: An image forming apparatus in which an image quality priority mode in which image density adjustment or image gradation control is effected to thereby give priority to the quality of an output image, and a speed priority mode in which gradation control is partly effected or is not effected to thereby output the output image within a short time can be selected by a user. A mode selection screen for selecting an image forming mode is displayed on the operating panel of the image forming apparatus. The image quality priority mode giving priority to the quality of image and the speed priority mode giving priority to speed are selectively displayed. When the user selects the image quality priority mode, and image control parameter is renewed immediately before image forming by image control, and the image forming is effected by the use of the renewed image control parameter, and when the speed priority mode is selected, at least part of the image control is not effected, but the image forming is effected.

Abstract: An image forming apparatus that uses a plurality of colorants for image formation and performs the image formation based on bitmap data in which each pixel has a gradation value of each color of the colorants, includes: a correction unit which executes a correction processing of correcting gradation values with respect to at least some pixels in which a gradation value of the colorants other than that of black color is 0 and a gradation value of the colorant of black color is not 0 in the bitmap data, wherein the correction unit executes different processing between a case in which the gradation value of black color of the bitmap data of the pixel that is a processing object is a maximum value and a case in which this gradation value is less than the maximum value.

Abstract: An image processing method for generating a gradation image, including the steps of: (a) acquiring a coordinate of a start point, a color value of the start point, a coordinate of an end point, and a color value of the end point; (b) setting either the number of pixels between the start point and the end point that is calculated on the basis of the coordinates that are acquired in the coordinate-and-color-value acquisition (a) or the number of colors between the start point and the end point, whichever is smaller, as the number of complementary colors of a complementary color list; (c) creating the complementary color list that has the number of complementary colors that is set in the complementary-color-number setting (b); and (d) generating the gradation image with the use of the complementary color list that is created in the complementary-color-list creation (c).

Abstract: A subject area extracting unit extracts a main-subject area from the color image data; a correction amount calculating unit calculates a gradation correction amount based on the information on the thus-extracted main-subject area; a control zone extracting unit extracts a predetermined control zone from a brightness zone to which the main-subject area does not belongs; a determining unit determines whether or not the gradation correction amount on the control zone should be controlled, according to a predetermined control requirement; and a control unit controls the gradation correction amount according to the determination result of the determination unit.

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: A facial image photographed by a digital camera is downloaded to a PC. When a facial image correction program starts, a correction window and a correction item selection window open on a monitor. When a user opens the facial image in the correction window, a pixel extraction circuit extracts pixels representing a skin area, an eye area, a teeth area, and a hair area from the facial image. Correction items to be performed are determined in the correction item selection window. A cursor position detection circuit detects the position of a cursor in the correction window. When the cursor is in one of the areas, a facial image correction circuit judges whether the correction item corresponding to the area is selected. If the corresponding correction item is selected, the facial image correction circuit subjects a pixel pointed by the cursor to predetermined correction processing.

Abstract: A printing apparatus includes a head having a plurality of ink discharging portions provided in a juxtaposed linear relationship. A discharging direction of an ink droplet to be discharged from each ink discharging portion can be deflected in a plurality of directions. A printing resolution is determined in response to print data from among a plurality of printing resolutions, and the ink discharging portion from which an ink droplet is to be discharged are selected based on the determined printing resolution. Further, the discharging direction of an ink droplet of each selected ink discharging portion is determined, and a discharge execution signal with which the discharging direction is specified is transmitted to the selected ink discharging portion so that printing is executed with the printing resolution determined in response to the print data from among the plurality of printing resolutions.

Abstract: A color sensor monitors the output of a color producing process and produces a signal representative of a color produced by the color producing process. The signal can be used as feedback signal to control the process. Occasionally, the color sensor signal includes a component representing a transient error. A system model of the color producing process is used to predict reasonable sensor signals. A comparison of the sensor signal with the predicted sensor signals is used to determine if the sensor signal is reasonable. If the sensor signal is unreasonable, a substitute signal is used as the feedback signal to the control process. The substitute signal can be a predicted sensor signal or a signal based on historical system performance data.

Abstract: This invention is a printing control apparatus for generating print data to be supplied to a print unit to print. The print unit is capable of forming dots on a print medium by ejecting at least one type of colored ink containing a color material and a quality-enhancing ink for enhancing quality of a printed material. The printing control apparatus includes an outline area extractor configured to extract an outline area of an image expressed by given image data and a dot data generator configured to generate colored dot data and transparent dot data according to the image data. The dot data generator is configured to reduce ink volume of dots formed in the outline area among the transparent dots.

Abstract: A bright luminance value, a dark luminance value, and an average luminance value relating to a face image portion included in an image represented by fed image data are calculated in calculating circuits. Further, a target bright luminance value and a target dark luminance value are calculated in a calculating circuit on the basis of a target average luminance value and a dynamic range that are inputted from an input device and the calculated bright luminance value, dark luminance value, and average luminance value. Interpolation processing based on a correspondence between the calculated bright luminance value, dark luminance value, and average luminance value relating to the face image portion and the target bright luminance value, the target dark luminance value, and the target average luminance value respectively corresponding thereto is performed in a corrected value calculating circuit, to create a look-up table.

Abstract: Conventionally, acquisition of color values from a color chart takes substantial labor and time. According to this invention, when the color value of each patch composing a predetermined line is input with each line of the color chart composed of a plurality of patches as the measurement unit, a measured line identification processor determines whether or not said line to be measured was measured in the predetermined measurement order, a warning section performs a predetermined warning processing if the measurement order for said line to be measured is no to correct, and when a color value acquisition line correction instruction is input to correct a line whose color value is expected to be acquired in said measurement order, a color value saving section makes the color value of said input each patch correspond to the gradation value of each patch composing said line to be measured.

Abstract: An image forming control apparatus includes: a gradation correction curve generator and a calibration data generator. The gradation correction curve generator generates a gradation correction curve based on a correspondence between an output instruction values each representing a density of an image to be formed by an image forming apparatus and actual density values each representing a density of the image formed by the image forming apparatus. The gradation correction curve represents a correspondence between predetermined standard density values and the output instruction values. When an output instruction value corresponding to a maximum standard density value is smaller than a maximum output instruction value, the calibration data generator corrects the gradation correction curve so that the output instruction value corresponding to the maximum standard density value coincides with the maximum output instruction value, and generates the calibration data based on the corrected gradation correction curve.

Abstract: An image processing device including a storage unit which stores, for set moving-target-positions of a lightness or gray axis on an uniform color space in color balance correction, color correction parameters for performing color balance correction corresponding to moving the lightness or gray axis substantially parallel to a specific moving-target-position on the uniform color space to inputted color image data, and a correction unit which, when color balance correction to the target color image data is instructed via an instruction unit, reads a color correction parameter corresponding to the instructed color balance correction among the color correction parameters stored in the storage unit, to perform color balance correction to the target color image data using the read color correction parameter, is provided.

Abstract: Even when an image signal is converted into an image signal with a limited amount of toner adhesion, the gradation is prevented from changing rapidly near the limiting value and therefore the image quality is prevented from deteriorating. An amount-of-adhesion converting circuit 301 converts image data for each color plane into first amount-of-toner-adhesion data. On the basis of a preset amount-of-toner-adhesion threshold value table, an amount-of-toner-adhesion reduction computing circuit 303 converts the first amount-of-toner-adhesion data for each color plane into second amount-of-toner-adhesion data with a limited amount of toner adhesion. Then, an image signal converting circuit 304 converts the second amount-of-toner-adhesion data into an image signal. In such a method, since parameters in the amount-of-toner-adhesion threshold value table are set arbitrarily, a rapid change in gradation can be suppressed near the limiting value.

Abstract: A plurality of parameters included in a predetermined illumination equation which defines a brightness are acquired for each pixel of an image. For each of the parameters, a homogeneous region including pixels which are similar in value of the parameter is specified. In each of the specified homogeneous region, each of the parameters is converted according to details of the predetermined image conversion. The brightness of each pixel of a second image is determined using the values of the parameters obtained after the conversion.

Abstract: An image pickup device includes a histogram generation unit which generates a histogram representing a brightness distribution of digital image data (RAW data) acquired during picture taking and a table change unit which calculates an amount of correction with reference to a target brightness value based on the histogram and changes gradation correction information of a gamma lookup table in accordance with the amount of correction. A gamma correction unit corrects gradation of the image data using the changed gradation correction information to generate a taken image whose brightness is corrected in accordance with the target brightness value.

Abstract: A method and system for performing spatial temporal multiplexing using a multi-threshold mask. A mask generator (404) outputs a threshold value for each pixel of a display. The mask generator typically creates a blue noise mask for a given pixel array that is replicated over the face of the entire display. The blue noise mask generator (404) typically is implemented as a memory lookup table. An index generator (402) provides an offset into the memory lookup table that allows the table to be shifted from time to time. The output of the blue noise mask generator (404), which may be the threshold value itself or a signal representing which threshold is being used, is an input to a selective inverter (406). The selective inverter (406) provides the option of inverting the blue noise mask. To reduce artifacts, the mask is periodically shifted and/or inverted. The value from the mask generator (404), whether inverted or not, is compared to the LSBs of the input data word to yield the fractional bit values.

Abstract: An image processing apparatus capable of duplex recording on two faces of recording paper on a basis of input image data, includes: a background adjustment section for performing a background adjustment on a basis of a plurality of background adjustment ? curves; a setting section for setting one background adjustment ? curve from the plurality of background adjustment ? curves; an image processing section for processing the input image data with the background adjustment ? curve set by the setting section; and an image output section for performing duplex recording control to the two faces of the recording paper on a basis of output image data to which the background adjustment is performed by the image processing section.

Abstract: A gradation pattern is printed, the gradation pattern is corrected with a gamma correction table TO based on a result in which the printed gradation pattern is read, the corrected gradation pattern is printed on a photosensitive drum or the like, and a measured density of the printed gradation pattern in S4 is stored as a reference value of density DR. Thereafter, without user's operation, at a set automatic timing, the read gradation pattern P is corrected with the gamma correction table TO and printed on the photosensitive drum or the like, density deviation ?D between a measured density D of the printed gradation pattern in S6 and the reference value of density DR is determined, and the latest gamma correction table T is generated and updated on the basis of the density deviation ?D. Consequently, high-quality image formation can be automatically performed.

Abstract: Radiometric calibration of an image capture device (e.g., a digital camera) using a single image is described. The single image may be a color image or a grayscale image. The calibration identifies and analyzes edge pixels of the image that correspond to an edge between two colors or grayscale levels of a scene. Intensity distributions of intensities measured from the single image are then analyzed. An inverse response function for the image capture device is determined based on the intensity distributions. For a color image, the radiometric calibration involves calculating an inverse response function that maps measured blended colors of edge pixels and the associated measured component colors into linear distributions. For a grayscale image, the radiometric calibration involves deriving an inverse response function that maps non-uniform histograms of measured intensities into uniform distributions of calibrated intensities.

Abstract: The present invention provides an image processing device which can reduce a storage capacity and perform color correction in accordance with the types of image. The image processing device of the present invention has an input correction section 6 including: input color correction section 24 for, using a matrix coefficient, correcting strength of signals for color components in image data of a supplied image; a matrix coefficient storage section 26 for storing a plurality of matrix coefficients in accordance with types of image; and control section 25 for reading a matrix coefficient corresponding to the type of a supplied image out of the matrix coefficients stored in the matrix coefficient storage section 26 and setting the matrix coefficient that has been read in the input color correction section 24.

Abstract: An image processing apparatus for generating a wide dynamic range image to enable contrast to be maintained in low luminance image areas and high luminance image areas when the image is displayed by a narrow density range display system having: an image data buffer in which short-time exposure image data is stored; an image area segmenting circuit for fractionating long-time exposure image data into areas of proper and improper exposure; a segmented area image information extracting circuit for segmenting the properly exposed area of the long-time exposure image data on the basis of the segmented information and segmenting the improperly exposed area as a properly exposed area by applying the short-time exposure image data; a gradation correcting circuit for gradation-correcting image data in the properly exposed areas of the long-time exposure and the short-time exposure images which have been segmented by the segmented area image information extracting means, respectively; and an image synthesizer for synth

Abstract: According to the invention, a value of a high density color material as a decomposition target is decomposed into a combination of the high density color material value and a low density color material value by using a value obtained by color-measuring a patch in which the high density color material and the low density color material are combined, a color measurement value of a patch formed by using the value of the high density color material as a decomposition target is compared with a color measurement value of a patch formed by using the values of the high density color material and the low density color material formed by decomposing, and the values of the high density color material and the low density color material formed by decomposing are corrected on the basis of the comparison result. A color separation table in which a color drift of 5 or more colors corresponding to each color does not occur can be formed.

Abstract: Image data by which an image is represented with a plurality of pixels is acquired. A portion of the image data characterizing an artificial image is extracted from the image represented by the acquired image data in an artificial-image extracting procedure. The prescribed image processing is performed by excluding the image data of the portion extracted from the acquired image data in the artificial-image extracting procedure. In this manner, the image processing can be performed without being affected by the artificial image.

Abstract: A gradation attributes correcting device to correct gradation attributes of an input image signal includes a brightness gradation correcting unit to correct gradation attributes with respect to brightness of an image indicated by the input image signal. The brightness gradation correcting unit includes a characteristic information acquisition unit, a correction information decision unit, and a brightness gradation processing unit. The characteristic information acquisition unit acquires a minimum, average, and maximum brightness, of an image on a frame from the input image signal. The correction information decision unit determines correction information to correct the gradation attributes with respect to brightness according to combinations of the acquired minimum, average and maximum brightness of the image on the frame.