Abstract: Systems, methods, and computer readable media for performing color correction operations to address memory color artifacts in a manner suited for real-time operations. In general, techniques are disclosed for correcting memory color rendering artifacts in an image without performing color space conversions. In one implementations, hue-saturation-value (HSV) image correction values may be expressed solely in terms of an image's base red-green-blue (RGB) color space values. Once expressed in this manner, color correction may be applied to the image directly—without the need to convert the image's color space into and out of a working color space (e.g., an HSV color space). As no color space conversions are necessary, the disclosed techniques are well-suited to real-time operations.

Abstract: System and methods for gamut bounded saturation adaptive color enhancement are provided. Color enhancement incorporating gamut bounded saturation enhances colors of an pixel from a source color gamut such that the resulting color is within a target color gamut. This resulting color may, for example, take advantage of an expanded target color gamut of a display. Gamut bounded saturation may be implemented independently or in combination with RGB bounded saturation.

Abstract: A method of calculating a correction value used when signal value correction is performed with respect to an image signal supplied to a display panel includes setting a target luminance value, which is not uniform in an overall surface of the display panel, as a target luminance value of one image signal value such that at least a portion of a distribution of target luminance values at each plane position of the display panel becomes a curved distribution, and calculating a correction value at each plane position of the display panel using luminance observed at each plane position of the display panel when one image signal value is given to the overall surface of the display panel and the target luminance value at each plane position of the display panel.

Abstract: There is provided a print data generating device which generates print data for printing using plural kinds of color material. The device includes a processor, and a memory storing computer-readable instructions which, when executed by the processor, causes the device to perform acquiring pixel data including grayscale values of plural color components corresponding to the plural kinds of color material, acquiring plural limitation values which are determined for the plural color components in the pixel data, respectively, and according to fixing characteristics of color material of the respective color components, to a print medium, determining a total allowable amount in printing a color represented by the pixel data based on the limitation values, correcting the pixel data such that a total amount of color material for the pixel data does not exceed the total allowable amount if needed, and generating the print data based on the corrected pixel data.

Abstract: A computer-implemented method and system for enhancing black density of a halftoned bitmap are provided. The method includes receiving a halftoned bitmap into computer memory, and, using a computer, identifying at least one black-only pixel in the halftoned bitmap. The method further includes for each of the identified black-only pixels, identifying at least one black-only pixel as a candidate for adding color based at least in part on the location of the black-only pixel with respect to an edge in the halftoned bitmap, modifying the halftoned bitmap by adding color to at least one of the candidate black-only pixels, and outputting the modified halftoned bitmap.

Abstract: An image processing device performs: defining determination regions based on image data; executing a first color conversion for the image data using a first type of parameter to generate a first image; determining an estimated amount of colorant for each determination region, the estimated amount indicating an usage amount of colorant to be used for each determination region when the first image is printed; outputting the first image if the estimated amounts of colorant for all determination regions are smaller than or equal to respective threshold values; and executing a second color conversion for the image data using a second type of parameter to generate a second image if the estimated amount of colorant for at least one is greater than the threshold value, the usage amount of colorant for the second image being smaller than the usage amount of colorant for the first image.

Abstract: An image-reading apparatus, includes a variation acquiring unit that acquires a variation of a distance or an angle between a medium to be read and an imaging unit or a light source, and a color shift correcting unit that calculates a color shift between the medium and the imaging unit or the light source based on the variation acquired by the variation acquiring unit and corrects the color shift.

Abstract: Provided is an image processing device which enables image display that takes full advantage of a color reproduction performance of a panel without providing a viewer with a feeling of strangeness. An image processing device includes: a color gamut conversion processor configured to convert inputted data into RGB data according to a liquid crystal panel; a weighting factor calculator configured to calculate a weighting factor; a first post-color-gamut-conversion data weighting processor configured to perform weighting processing to the RGB data; an inputted data weighting processor configured to perform weighting processing to the inputted data; and an output adder configured to add data after the weighting processing to generate RGB data to be supplied to the liquid crystal panel.

Abstract: An image processing apparatus is disclosed. The image processing apparatus includes a color conversion processing unit which obtains CMY data from input color space coordinate data of image data, and an output data generating unit which generates output data by forming CMYK data by using a result output from a color conversion processing section. The color conversion processing section includes an optimum color reproduction data structure which gives the CMY data for obtaining a full color image optimally reproduced from the input color space coordinate data, and a color material using amount reducing data structure for outputting the input color space coordinate data by reducing the color material using amount with the use of a reference value in which the color material using amount is increased for a hue of an output image giving a high psychological effect and is decreased for a hue of the output image giving a low psychological effect.

Abstract: An image forming apparatus includes an image forming unit, a storage unit, an image processing unit and a control unit. The image processing unit (i) calculates a summed height of a color toner image formed on a sheet by summing up a height of the color toner image on the basis of input image data, (ii) calculates, on the basis of a target value for glossiness stored in the storage unit, a target total height of the color toner image and a clear toner image to realize the target value for glossiness, and (iii) calculates a height of the clear toner image by subtracting the summed height from the target total height. On the basis of the calculated height of the clear toner image, the control unit adjusts the height of the clear toner image formed on the sheet.

Abstract: This invention relates to a conversion table compression method of compressing a conversion table and storing the conversion table in a storage medium, including an axial difference creating step of creating an axial difference table by calculating, from data stored in the conversion table, the difference values between grid points adjacent in predetermined directions along a plurality of axes which define the input space of the conversion table, a compressing step of compressing the axial difference table to create compressed data, and a storing step of storing the compressed data in a recording medium.

Abstract: An image forming apparatus includes an image forming station for forming a pattern image on a recording material; an image reading station for reading a pattern image formed on a recording material by the image forming station; and a tone gradation corrector for calculating a halftone dot area property on the basis of the density of the pattern image read by the image reading station and for executing tone gradation correction in the image forming station on the basis of the calculated halftone dot area property.

Abstract: Disclosed are a device, a method, and a storage medium to create a color conversion table. According to one implementation, a color conversion table creating device includes, a color material amount limiting processing section; a first color conversion processing section; a second color conversion processing section; a combining section; a color material amount limiting inverse conversion processing section; and an output value determining section. The color material amount limiting processing section performs color material amount limiting of an input value in the color conversion table. The color material limiting inverse conversion processing section performs inverse conversion of the color material amount limiting after color conversion and combining the CMYK components. The output value determining section sets the inverted CMYK color components as an output value in the color conversion table.

Abstract: The method of storing profile set storage method according to the present invention comprising (a) selecting as reconstruction data that enables to reconstruct a profile set, either size prioritized data, which is smaller than said profile set, or reconstruction speed prioritized data, which enables to be reconstructed within a shorter time period than is required for reconstructing the size prioritized data, and which is smaller than the profile set but is larger than the size prioritized data; (b) for generating the selected reconstruction data based on the profile set; and (c) storing the reconstruction data generated in the step (b) in a storage device.

Abstract: An image processing apparatus processes image data including first data corresponding to an output color of an output device and a plurality of second data of respective spot colors. The image processing apparatus includes a conversion section and a storage section. The conversion section calculates a device color value for a spot color or a spot color combination among the spot colors, referring to a first table, to generate a second table. In the second table, spot color identification information on the spot color or the spot color combination is correlated with the device color value. The conversion section also generates third data based on the plurality of second data. In the third data, each pixel is represented by the spot color identification information. The storage section stores the first data, the second table and the third data.

Abstract: A print color predicting apparatus, a print color predicting method, and a recording medium having a program recorded therein acquire a spectral reflectance of a print, estimate a plurality of sets of optical property values of a protective film that covers the print, depending on the spectral reflectance of the print, and predict a spectral reflectance of a protective-film-covered print, using the spectral reflectance of the print and the sets of optical property values of the protective film.

Abstract: To generate a color separation table for an image forming apparatus which has relatively dark/light color materials with high/low relative densities, a gamut boundary for limiting the use of the relatively dark color material is set. One of relatively dark color materials is selected, and at least a grid point which satisfies a condition that the color material value of the selected relatively dark color material is nonzero and a color value to be reproduced based on color material values set to the grid point exists in a region brighter than the gamut boundary is determined. The color material value of the selected relatively dark color material set to the grid point which satisfies the condition is replaced by the color material value of the relatively light color material.

Abstract: System and methods are provided for performing saturation adjustment of one or more pixels. In one embodiment, an input color value of a pixel is received. The input color value includes an input saturation component. An adjusted color value is extracted from a predetermined look-up table that maps the input color value to the adjusted color value, the adjusted color value having an adjusted saturation component that is different from the input saturation component. The adjusted color value is output.

Abstract: Force K processing is presented to replace gray color values of input data with only levels of black ink/toner when color management is not specified in the print job. A system converts input data of a print job to a CMYK color space of a printer by processing a lookup table of color values for the color space of the input data based on a detected color space of the input data to identify gray color values of the lookup table. The system also determines that these gray color values produce an output in the CMYK color space of the printer that includes one or more of cyan, magenta, and yellow color components. The system replaces the gray color values with black color values and corresponds the black color values of the lookup table with gray color values of the input data for conversion of the input data.

Abstract: Systems are provided for determining toner color having a processor that generates a fluorescent toner color image that when printed using a corresponding fluorescent toner will generate a diffuse fluorescent color light that reduces the extent to which noise induced variations in density in a noise evident portion of a toner print are observable. The processor further adjusts reflective toner color images used to form the toner print so that the reflective toner color images combine with the fluorescent color image to form a target color image.

Abstract: A pixel extracting unit extracts pixels belonging to a previously designated color range from the image data of a correction object. A target color selection receiving unit receives a selection of one target color by a user, from among a plurality of target colors stored in a target color storage unit. A color correction executing unit executes color correction on correction object image data, based on the color of the pixel extracted by the pixel extracting unit and the target color selected through the target color selection receiving unit. A target color extracting unit extracts the target color of a registration object from target color registration image data stored in a registration image storage unit. A target color registration unit registers the target color of the registration object extracted by the target color extracting unit in the target color storage unit to be associated with a previously designated color range.

Abstract: A device link profile creation method including: storing a plurality of device link profiles in a storage unit with information about a first device profile which is used to create one of the plurality of device link profiles, for each of the plurality of device link profiles; storing the first device profile in the storage unit; and performing control by a control unit to: when the first device profile is updated to be a second device profile, detect the second device profile; detect a first device link profile which is created by using the first device profile, as a device link profile to be updated; automatically create a second device link profile by using the second device profile; and update the detected device link profile to be updated by replacing the device link profile to be updated with the created second device link profile.

Abstract: An image reading device includes a first reader member that receives light from a medium to read an image recorded on a surface thereof; a second reader member that separates the light from the medium and reads a color of the recorded image based on the separated light; a deriving unit that derives associating information that associates a first read result with a second read result based on the first read result and the second read result, the first read result being obtained by the first reader member, the second read result being obtained by the second reader member; and a measuring unit that measures the color of the image on the medium for performing color calibration by reading the medium by using the first reader member so as to determine a color corresponding to the second read result based on the first read result and the associating information.

Abstract: Systems for determining toner colors to be combined to form a target color at a location on a receiver. In one aspect, a system has a processor that determines a fluorescent toner color to be provided at the location based upon the density and hue angle of the target color and that determines one or more reflective toner colors to be provided with the determined fluorescent toner color at the location to form the target color in which the amount of the fluorescent toner color is decreased as the target color density increases.

Abstract: Systems and methods are described that facilitate reducing metamerism in a scanner or printer system by evaluating and manipulating unfiltered clear channel information. Using a four channel model to predict CIE XYZ tristimulus values from RGB and clear, a linear model is generated based on a polynomial matrix conversion. For example, one such model has coefficients weighting 1, R, G, B, W, R2, G2, B2, W2, RG, RB, RW, GB, GW, BW, and corresponding third order terms. The XYZ values predicted by the linear model are converted to L*a*b*, and compared with measured L*a*b* values. A statistic involving the difference between measured and computed L*a*b* values is used as a metric in a non-linear optimization to obtain the best values for the matrix elements. Once the matrix is optimized, it is employed for printer calibration, error detection, and the like.

Abstract: A converting unit executes a color conversion process for image data according to a normal profile when a determining unit determines that a prescribed setting is not set for the image data. The converting unit executes the color conversion process for the image data according to a colorant-saving profile configured such that an amount of colorant to be used in the colorant-saving profile is smaller than that in the normal profile when the determining unit determines that the prescribed setting is set for the image data. One of a plurality of input color values of the image data is converted to one of the plurality of output color values according to the colorant-saving profile in the color conversion process. The one of the plurality of input color values has a first hue. The one of the plurality of output color values has a second hue different from the first hue.

Abstract: An image processor includes: a receiving unit that receives an input of image data in a first color space; a first color conversion unit that performs color conversion of the image data received by the receiving unit to image data formed of a first combination of color components in a second color space; a second color conversion unit that performs color conversion of the image data received by the receiving unit to image data formed of a second combination of color components in the second color space, the second combination being different from the first combination; and an image generating unit that generates an image based on at least the image data generated by the first and second color conversion units. Each of the first and second combinations includes a smaller number of color components than the number of color materials to be used in formation of an image.

Abstract: Provided is an image processing device which enables image display that takes full advantage of a color reproduction performance of a panel without providing a viewer with a feeling of strangeness. In at least one embodiment, an image processing device includes: a first color space converter configured to convert an externally transmitted RGB signal into an XYZ signal; a three-dimensional matching processor configured to perform conversion to tristimulus values of the XYZ signal to generate an XYZ signal; and a second color space converter configured to convert the XYZ signal to an RGB signal for a liquid crystal panel.

Abstract: A scanner device and a method executed in the scanner device are provided. The scanner device includes a generating unit that generates original image data representing a scanned original; a preparing unit that prepares one color-conversion profile among a plurality of color-conversion profiles having different data sizes, according to a feature of the original image data; and an outputting unit that outputs the original image data and the one color-conversion profile.

Abstract: A data transmission device and a method thereof. A fax driving unit converts a document into a fax data recognizable by a first multifunction machine, and creates a fax event including a fax information event which instructs to transmit the converted fax data to a second office machine and a fax number of the second office machine. A printer spooler spools the converted fax data and outputs the spooled fax data and the fax information event. A communication port transmits the spooled fax data and the fax information event to the first multifunction machine. The first multifunction machine transmits the fax data to the second multifunction machine based on the transmitted fax information event. Accordingly, data communication errors are prevented which occur between a host personal computer and a multifunction machine while transmitting the fax data.

Abstract: An image processing apparatus includes a patch forming unit that forms a plurality of mixed-color patches by superposing single color patches of a plurality of colors with different gradation ratios according to gradation values; a color measuring unit that performs color measurement of the mixed-color patches; an estimating unit that estimates color values of single colors present in the mixed-color patches based on color measurement values obtained by performing color measurement; and a correction table setting unit that sets a correction table in order to correct the estimated color values of the single colors to target color values.

Abstract: A user of an image forming device selects from among a plurality of pre-stored color rendition dictionaries (CRDs) in order that a set of system process parameter setpoints associated with that CRD may be referenced to bias and/or skew an available color gamut in the direction of a particular nominally out-of-gamut color which the user wishes to produce in a color image output by the image forming device. A capability is included in a color image forming device store and/or update multiple sets of special process parameter setpoints defining a plurality of CRDs each of which may be identified and associated with a specific color in order that requests to print out-of-gamut colors may be satisfied routinely as exceptions to a nominal gamut based on a nominal set of stored setpoints when a CRD is selected and the setpoints associated with that CRD are input for reference by the color image forming device on a temporary basis.

Abstract: An image correction method is applied to a scanner device. The scanner device includes a main case, a drive module, an optical module, an analog-to-digital converter, a first-in and first-out data buffer, a data flow control unit, a set unit, a data classification unit and a memory storage unit which are electrically connected and assembled in the main case. The scanner device executes a program statement set by the set unit in the memory storage unit to get values for building an update shading table. The scanner device utilizes the update shading table to compensate pixel values corresponding to red, green and blue light of each scanned line of an image for doing a luminance compensation of image pixels corresponding to the red, green and blue light of each scanned line of the image so as to complete an image correction of each scanned line of the image.

Abstract: An image processing system includes a first image processing apparatus and a plurality of other image processing apparatuses that are connected with each other via a network. The image processing system includes a sharing unit included in at least the plurality of other image processing apparatuses and configured to store information stored in a storage unit of the first image processing unit to share the information, a determination unit configured to determine an image processing apparatus to use the information to be shared from the plurality of other image processing apparatuses when the first image processing apparatus is not available, and an alternative operation unit configured to perform an alternative operation for a function of the first image processing apparatus using the information shared by the sharing unit of the image processing apparatus determined by the determination unit.

Abstract: An image forming apparatus including an attribute-value-information holding unit that holds an attribute-value table showing correspondence between a type of gradation processing and a fixing-temperature control attribute value; an image-formation-attribute processing unit that determines a type of gradation processing and a corresponding fixing-temperature control attribute value on the basis of contents of a print instruction and the attribute-value table; a gradation processing unit that performs gradation processing in accordance with the type of gradation processing determined by the image-formation-attribute processing unit; and a fixing-temperature control unit that controls fixing temperature in formation of a print image according to the fixing-temperature control attribute value determined by the image-formation-attribute processing unit.

Abstract: Conventionally, it is not possible to evenly correct a color conversion table of a reading device in the entire color region even with a limited number of patches. In order to correct a color conversion table, a color conversion table from a device-independent color space into a device-independent color space is newly stored. A shift in read data between devices is reflected in a correction 3D-LUT and a color conversion table is corrected using the correction 3D-LUT. Thereby, it is possible to correct the entire color region with a smaller number of pieces of data and with less time and effort than when a color conversion table is newly recreated.

Abstract: A method of printing a high density image on a transparent medium. In some examples, the method includes calculating an expected optical density for an input pixel value, using a first function configured to output an optical density which produces a substantially linear relationship between the input pixel value and the output optical density as substantially perceived by a human eye. The method may also include calculating an L* value which represent a parameter in a CIELAB colorspace using the expected optical density. In some examples, the method includes calculating a response function that describes the relationship between L* and an output pixel value, the output pixel value specifying the amount of ink to deposit onto the transparent medium. In other examples, the method includes using the response function to solve for an output pixel value for the L* value; and creating a look up table.

Abstract: A method for compensating for effects of illumination when comparing soft proofs to hard copy proofs viewed under non-standard illumination comprises adjusting a standard illumination display profile until estimates of device independent colors produced by the display based on the adjusted profile match the colors corresponding to the non-standard illumination within a predefined tolerance.

Abstract: A gradation-correcting curve to correct a gradation of an input image is generated. Gradation correction based on the gradation-correcting curve is made to a boundary pixel of a color-reproduction space at the same saturation as that of a target lattice point and at a hue of the target lattice point. An equal-saturation line is set by using the boundary pixel of the color-reproduction space after the gradation correction. A saturation-correction amount of the target lattice point is decided based on the gradation-correcting curve and the equal-saturation line.

Abstract: An information processing apparatus acquires communication setting information for communicating with an image processing apparatus by a second communication unit via a first communication unit. In accordance with the acquired communication setting information, communication by the second communication unit is established to execute, via the second communication unit, an image processing service provided by the image processing apparatus. When establishment of communication is detected, an operation window display request for executing the image processing service is transmitted via the second communication unit. The image processing apparatus receives the operation window display request from the information processing apparatus via the second communication unit. In accordance with the received operation window display request, an operation window for executing the image processing service is displayed.

Abstract: Transfer functions are often used for image processing. Look-up tables can be used to implement transfer functions in a processor-efficient manner. In one embodiment, the invention is an apparatus that includes a look-up table (LUT) storing sample outputs from an output range of a transfer function, the sample outputs corresponding to sample inputs from an input range of the transfer function, the sample inputs being distributed so that more sample inputs are associated with a first region of the transfer function than a second region of the transfer function; and an address module to calculate an index into the LUT based on image data. In one embodiment, the apparatus uses the LUT to process the image data.

Abstract: Systems and methods systems and methods for calibrating field uniformity are disclosed. An exemplary method includes scanning the imaging area including a first media to obtain optical data for a specular reflectance map. The method also includes scanning the imaging area including a second media to obtain optical data for a diffuse reflective map. The method also includes storing the specular reflectance map and the diffuse reflective map for adjusting actual pixel values during an imaging operation.

Abstract: An apparatus includes a contact image sensor (CIS) configured to parallelly output image signals of a plurality of pixels via a plurality of signal lines, an analog frontend (AFE) configured to serially output the image signals of the plurality of pixels output from the CIS by converting the image signal into a plurality pieces of pixel data, an input/output control circuit configured to add reading position information and reading color information to each of the plurality pieces of pixel data, and a direct memory access controller (DMAC) configured to transfer each of the plurality pieces of pixel data to a storage position corresponding to the reading position information and the reading color information such that the plurality pieces of pixel data is stored in consecutive storage positions in an external memory.

Abstract: A color adjustment device includes: a conversion unit that converts color values of a second color space stored in a color conversion table, which defines a correspondence relation between color values of a first color space and color values of the second color space, into color values of a third color space independent from a device outputting an image; a storage unit that stores tables that define different input-output characteristics depending on color values of the third color space; and a change unit that selects at least one table from the tables according to a specified adjustment method, and executes a change process that changes color values of the second color space stored in the color conversion table by using the at least one table.

Abstract: An image forming apparatus with a plurality of reading units, which is capable of easily adding a recording sheet type usable for calibration. Calibration is executed using a specific recording sheet. Gradation patterns are formed on a recording sheet of a sheet type to be added, and are read by a reader unit. A first conversion table is configured based on information on the read image. A second conversion table is configured based on the first conversion table. When the reader unit is used to perform calibration using the added recording sheet, image forming conditions are set based on information on the image read by the reader unit and the first conversion table, and when the color sensor is used, the image forming conditions are set based on information on the image read by the color sensor and the second conversion table.

Abstract: An image processing device includes a multi-layer data acquiring part configured to acquire multi-layer data having a required-formation-amount-related value representing a value relating to a formation amount required to form an image, and an expanding part configured to expand, based on a correspondence relationship for expansion, the acquired multi-layer data into multiple sets of single-layer data. The correspondence relationship for expansion has a correspondence relationship between the required-formation-amount-related value in each of the sets of single-layer data and the required-formation-amount-related value in the multi-layer data. The required-formation-amount-related value in the multi-layer data is image data that exceeds a maximum-formation-amount-related value representing a value relating to a maximum formation amount of a color value of the single-layer data with which an image can be printed in a single printing process.

Abstract: An image processor having an image compression unit to generate first compressed image data by dividing input image data into blocks of M×M pixels with regard to at least luminance signals (Y) of the input image data, wavelet-converting the image data in units of blocks, and reducing the number of bits by quantization, a memory to store the first compressed image data, a coordinate calculator to calculate coordinates to deform images by coordinate conversion and output coordinate information, a compressed image deforming unit to generate compressed deformed image data by reading out the first compressed image data stored in the memory while conducting coordinate conversion based on the coordinate information from the coordinate calculator, and a first image decompression unit to decompress the compressed deformed image data to obtain decompressed image data.

Abstract: An optical writing control apparatus controls a light source to draw a correction pattern for correcting a parameter value of an image forming mechanism, detects the correction pattern transferred onto a conveyance member from a photosensitive member based on an output signal of a sensor, and corrects the parameter value based on the detected correction pattern; stores chromatic color progress information indicating a progress for a chromatic color mechanism corresponding to a chromatic color image occurring from when the correction operation was carried out and achromatic color progress information indicating a progress for an achromatic color mechanism corresponding to an achromatic color image occurring from when the correction operation was carried out; and stores a necessary threshold to determine that the correction operation is necessary and an unnecessary threshold to determine that the correction operation is unnecessary for the chromatic color progress information and the achromatic color progress i

Abstract: In a first embodiment, a display system comprises a display panel with 4 or more colored subpixels. The display system receives input image data specified in a first color space and outputs image data specified in a second color space. The display system further comprises a gamut mapping module for mapping the input image data specified in the first color space to image data specified in the second color space. The gamut mapping module clamps out-of-gamut colors using at least a first clamping system and a second clamping system. The first and second clamping systems yield first and second clamped values. A weighting module produces a resulting clamped value from the first and second clamped values. A final output image value is derived from the resulting clamped value. Other embodiments of the display system include pre-reduction modules and adjustable GMA modules.

Abstract: A display drive circuit of the invention has: an initial-color-gamut-apex-coordinate-storing unit capable of storing initial color gamut apex coordinates; a user-target-color-gamut-apex-coordinate-storing unit capable of storing user target color gamut apex coordinates; a saturation-expansion-coefficient-deciding unit for deciding expansion coefficients of saturation data based on the initial and user target color gamut apex coordinates; and an expansion unit for expanding saturations of display data based on the saturation expansion coefficients. The expansion coefficients of saturation data are decided based on the initial and user target color gamut apex coordinates, and saturations of display data are expanded according to the expansion coefficients. Thus, the degree of expanding the saturations can be controlled for each color gamut or each of R, G and B color properties of an LC display panel.