KR20070017100A - System and method for display device characterization, calibration, and verification - Google Patents

Abstract

The present invention provides a system for generating (FIG. 3) characterization information from a first display device (block 760 of FIG. 3) that can be transmitted and used by a second display device (block 82 of FIG. 3); It is about a method. Computer readable instructions embodied in computer readable media calibrate the first display device (block 70 of FIG. 3), generate an ICC color profile from the calibration information (block 72 of FIG. 3), Store the ICC color profile, and transmit the ICC color profile to the second display device for use. In addition, calibration or characterization information is associated with the image file and may be sent to a second location for display (FIG. 3).

Gray lamp, color profile, display device, color space.

Description

SYSTEM AND METHOD FOR CHARACTERIZATION, CALIBRATION, AND VERIFICATION OF DISPLAY DEVICES

The present invention relates to systems and methods for the characterization, calibration and verification of characterization and calibration information associated with display devices. In particular, the present invention characterizes or calibrates a display device, sends such characterization or calibration information to a second or subsequent display device, and uses the characterization or calibration information to standardize the second or subsequent display device. And a computerized system for verifying that characterization or calibration information can be suitably used by the second or subsequent display device.

In many aspects of commerce, color decisions are made daily. When consumers buy a product, color has a major influence on the purchase decision. In current commerce, it is possible to make purchases via the Internet or other virtual means. This possibility has made the display of accurate, precise color and color appearance more important because these displays represent the color of the physical products in the presentation. If you believe that a product is one color, and you have purchased the product over the Internet and have received the product and find that the color at the time of purchase is not displayed properly, the buyer will be disappointed.

In addition, the ability to reproduce accurate and accurate colors in display devices is important in advertising, product packaging, and product production businesses. When the components are created, as described in US Pat. No. 6,381,343, online virtual collaboration systems can be used to inspect and approve proofs and prototypes of print images. In such cases, it is desirable to use a system and method for calibrating display devices from a first display device to a second or subsequent location, as well as verifying that the second or subsequent display device can use the characterization information. Will be beneficial. Thus, when such information is properly applied, the color of the product on the first device will be as identical as possible when viewed on the second or subsequent display device.

As such, providing a system and method that allows verification and calibration of display devices from a first display device to a second or subsequent display device is a matter of great care.

To meet this need, it is an object of the present invention to provide a system and method for calibrating a second or subsequent display device in accordance with the characterization information of the first display device.

It is another object of the present invention to provide a system and method for verifying characterization or calibration information of a second or subsequent display device in accordance with the characterization or calibration information of the first display device.

The objects are achieved by a system for generating characterization information for a first display device for use with a second display device, the system comprising: computer readable media in communication with the first display device; And a set of computer readable instructions embodied in the computer readable media. The computer readable set of instructions initializes lookup table values indicative of default luminance levels of the first display device, measures the output of the first display device in accordance with the initialized lookup table values, and in accordance with the output measurements. Determine a gray ramp, map L * of the CIELAB color model of the gray ramp and the first display device, adjust the lookup table values according to the gray ramp mapping and L *, and an RGB color map Measuring information and determining an ICC profile according to the gray lamp and the RGB color map information.

 The objects are also achieved by a system for using characterization information from a first display device, the system comprising: computer readable media in communication with a second display device; And receive characterization information indicative of color characterization of the first display device, determine whether the second display device can use the characterization information, and the characterization information for displaying images on the second display device. Consists of a set of computer readable instructions embodied within the computer readable media for use in the purpose of.

The objects are also achieved by a system for calibrating a first display device having at least one lookup table, the system comprising: computer readable media in communication with the first display device; And initialize at least one lookup table of the first display device to default values according to a predetermined white point, measure the output of the first display device using a display measurement device, and determine a desired white point value. Modify the at least one lookup table according to the measured output until they are obtained, generate a gray ramp by mapping gray values from the first display device measurements to L * of a CIELAB color model, and Adjust at least one lookup table according to a lamp, measure an RGB color volume of the first display device, determine a gamut map of the first display device, and measure the measured RGB color volume, gray ICC color according to lamp, at least one lookup table, and the gamut map Consists in a set of computer readable instructions embodied in said computer readable medium to generate the file.

The objects are also achieved by a method for generating characterization information for a first display device for use with a second display device. The methods include: initializing lookup table values of the first display device; Measuring the first display device output to generate display device measurements; Determining a gray lamp according to the measurements; Mapping L * of the gray lamp and the CIELAB color model; Adjusting the lookup table values according to the gray ramp mapping; And determining an ICC color profile according to the gray lamp and the adjusted lookup tables.

The objects are also achieved by a method for generating characterization information for a first display device for use with a second display device, the method comprising: initializing lookup table values of the first display device; Segmenting the first display device into a plurality of grating regions; Measuring at least one output of the grating regions; Determining a gray lamp according to the measurements; Mapping L * of the gray lamp and the CIELAB color model; Adjusting the lookup table values according to the gray ramp mapping; And determining an ICC color profile according to the gray ramp and the adjusted lookup table values.

1 is a flow chart of the present invention.

2 is a flow chart of the present invention.

3 is a schematic diagram of hardware associated with the present invention.

4 is a schematic diagram of an RGB color space.

5 is a schematic diagram of display device grating regions.

6 is a flowchart of the present invention.

The following detailed description may be provided with respect to program procedures executed on a computer or a network of computers. These procedural descriptions are expressions used by those skilled in the art to more effectively convey the substance of this work to others skilled in the art. These procedures described herein are generally self-consistent sequences of steps that produce desirable results. These steps require physical manipulations of physical quantities, such as electrical or magnetic signals, that can be stored, transmitted, combined, and compared, or manipulated readable media designed to perform a particular task or tasks. . The actual computer or executable code or computer readable code may span multiple computers or storage media rather than being contained in a file or a storage medium. The terms "host" and "server" can be either hardware, software, or a combination of hardware and software that provides the functionality described herein. Accordingly, the present invention allows a plurality of geographically dispersed users to interact with data regarding the physical characteristics of the products produced using a system that ensures accurate and accurate delivery of information (data).

The invention is described below with reference to flowchart illustrations of the methods according to the invention, an apparatus ("systems") and computer program products. Each block of the flowchart example may be implemented by computer readable instructions or code set. These computer readable instructions are loaded onto a general purpose computer, special purpose computer, or other programmable data processing device such that the instructions are executed on a computer or other data processing device to implement the functions specified in the flowchart block or blocks. It is possible to produce a machine that creates a means for doing so.

In addition, these computer readable instructions enable a computer or other programmable data processing apparatus to produce an article of manufacture in a particular manner—instructions stored in a computer program medium comprising an instruction means to implement the functions specified in the flowchart block or blocks. In a computer-readable medium guiding to act in a fashion. In addition, computer program instructions may be loaded onto a computer or other programmable device to execute a computer execution process, wherein the instructions are executed on a computer or other programmable device to provide steps for implementing the functions specified in the flowchart block or blocks. Can be generated. Thus, the elements of the flowchart support combinations of means for performing special functions, combinations of steps for performing specific functions and program instruction means for performing certain functions. Each block of the flowchart illustrations may be implemented by special purpose hardware based computer systems in which specific functions, steps or special purpose hardware or computer instructions perform combinations. The invention is explained more fully with reference to the drawings, in which preferred embodiments of the invention are shown. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The intensity, correlation color temperature, and response of the display devices are calibrated, so that the same hue of the manufactured product is displayed and the viewer perceives the product as if it is located in the corresponding environment provided by the display device. Can be. Color intensity is the hue degree or hue depth of a color. Color intensity is also known as Chroma in hue (color), lightness, and saturation (saturation) scale indicators, such as Munsell color order indicators. The correlated color temperature is defined as the temperature of the blackbody placed closest to the u ', v' coordinates in the CIELUV system and the temperature of the isothermal temperature line perpendicular to the blackbody location on the CIE XYY chromaticity diagram. Display devices are calibrated sequentially for a number of luminants, which include Daylight D65 with a 6500 degree Kelvin color temperature; Fluorescent with a 4158 degree correlated Kelvin color temperature; And 2856 degrees Tungsten, which has a Kelvin color temperature, thereby maintaining color invariance when viewing products manufactured under multiple light emitters. The illuminant defines the spectral distribution of visible light emitted from the light source. Although the light emitters herein are typical of those used in the industry, the present invention may use many other light emitters or light emitter combinations. In the graphic arts industry, for example, the standard illuminant for proofing is a black body with a D50 or 5,000 degrees Kelvin color temperature. Another component of the characterization procedure is the adjustment of the brightness or brightness level. The brightness level is the property of emitting light, ie emitting light, which level affects color perception, so that observations made on multiple monitors must be adjusted to the same brightness level to provide constant evaluations. Brightness levels greater than 200 cd / cm 2 on display devices are preferred. The characteristics of such a display device are referred to as characterization information of the display device.

Referring to FIG. 1, step 10 includes initializing a Video Lookup Table (LUT) to default values prior to measuring white points. An LUT is a data structure that maps the gamut or color space of one device to the gamut of another device. The “white point” is the point at which the illuminant can produce in the illuminator dependent color space. For example, white reflected from outdoor daylight generally serves as a white point for this light emitter. Indoors at night, white reflected from a single lamp light serves as a white point for this light emitter. The first display device is then measured by spectrometer or color system for the particular illuminant to determine the display output in step 12. Spectrometers or colorimeters are used as display measurement devices and measure or quantify the relative output of the display device for any given input. In the measurement of the first display device, the spectral transfer function {STF (VD1) (λ)} is determined by measuring the RGB signal generated by the linear combination of RGB signals of 0,0,0 to 255,255,255 for each RGB. . If the brightness is too high in step 14, in step 16 it is determined whether digital control of the display device is available. If so, in step 18, the brightness of the display device is reduced and the operation returns to step 12. If digital control is not available at step 16, then at step 20, the end points of the LUT are proportionally reduced and operation continues to step 12. If the brightness is not too high, in step 22, color temperature determination is made for the white point. If the color temperature is not correct, in step 30, the end points of the LUT are changed by adjusting the RGB of the display device according to the white point. If the color temperature of the white point is correct, in step 34, the gray scale is measured in increments from zero percent black to full scale or one hundred percent white. Gray color can be generated when the RGB signals are increased. The gray lamp is a series of zero to full scale colors. Each new color, or incremental value of RGB, is slightly brighter than the last value. Equivalent gray lamps are calculated using a CIELAB color model using component parameters (L *). L * accounts for nonlinearity in human visual systems and helps linearize these nonlinear brightness / signal perceptions. In step 36, the present invention maps the gray scale linearity with the lightness function L *. Step 38 sets the LUT according to the resulting values of the mapped gray scale and stores the results. The endpoints of the LUT are corrected to scalar values using white points, so that the overall color difference is less than 0.2 units, CIELAB ΔE * ab. The LUT is adjusted until the desired white point values of 0% to 100% white are obtained. Step 40 measures, evaluates and corrects the final gray ramp linearity until errors are less than 0.2 units, CIELAB ΔE * ab. In step 42, an RGB color solid is measured and an ICC profile is determined according to the gamut map. A gamut map is a color cube representing obtainable colors that can be generated by a device such as a printer or display device. These three-dimensional color spaces or maps, which often represent device dependent color gamuts, are different, and thus, a gamut-mapping algorithm to facilitate mapping from gamut colors when moving image data between devices with different color gamuts. This is necessary. In step 44, the ICC profile and gamut mapping is stored. For efficiency, the preferred embodiment measures 33 gray steps between 0% black and 100% white, representing full scale rather than possible integer points of 0 to 100 in step 34. The 33 points correspond only to the approximate number of discernible differences in the component values L * of CIELAB. In a typical LUT, there are 256 (0 to 255) dots between 0% black and 100% white. The values derived from these calibration procedures are stored in the LUT so that the input signal to the display device is modified, thus greatly reducing errors in the display devices. The display device is characterized or profiled by measuring a three-dimensional color volume, which spans an RGB cube. An RGB cube is a representation of the RGB color gamut in the RGB color space. The cube is configured as a right coordinate system with XYZ that maps directly to RGB. The corners of the cube are primarys; Red (R), green (G), and blue (B) are shown. RGB cubes are shown in FIG. 4. Black is shown at the bottom, rear corner with R = 0%, G = 0% and B = 0%. White is shown as R = 100%, G = 100% and B = 100%. For illustrative purposes, the number 1 is used to represent a full-scale signal, which can also be assigned a value 255 on the hex scale. Data from the spectrometer or color system is stored in the LUT. In step 42, the resulting measurements are converted to an RGB-> L * a * b *-RGB table. Additionally, in step 42, a standard ICC display profile is created or edited according to the RGB-> L * a * b *-RGB table. The LUT is added to the ICC profile to provide full characterization of the display at the moment of step 43. In addition, the user of the system can specify to calibrate the display device using low brightness, thereby facilitating viewing of images on other display devices of low quality and / or brightness capabilities. If so, step 12 to step 30 are repeated. This reduction in brightness can be achieved by repeatedly reducing the white end of the video lookup table while maintaining the desired color of the illuminant, or the display device can be changed via programmatic means such as the DCC 2ci protocol by VESA. In the case, the brightness of the display is temporarily reduced while maintaining the desired correlated color temperature of the illuminant through gain controls. The resulting new luminance values are added as additional information in the ICC profile.

In many applications, such as for proofing sessions of digital images, new settings for display devices are needed. Thus, the desired luminance is selected and the resulting ICC profile is associated with the proof session or task. When this task is viewed sequentially, previous characterization results are retrieved and loaded. Verification displays a set of grays and colors on the display device, measures the luminance output of the display device with a spectrometer or color system, and measures the results using an RGB ⇒ L * a * b * insertion table in the ICC profile. This is done by comparing the original measurements derived by calculating L * a * b * values. Standardized error measurements, called CIELAB ΔE * ab or CIELAB ΔE94, are used to compare magnitudes and to evaluate the visual impact of chrominances.

In other applications, it is desirable to simulate a CMYK print from a printing press or digital proof by displaying the corresponding digital image. In this case, the spectrometer measures a set of 300 to 2000 color patches. ICC profiles are generated from this data. A set of tables of L * a * b * ⇒ CMYK ⇒ L * a * b * is generated and forms the basis of the resulting ICC printer profile for each device. This profile is selected in the viewing application and is linked to the ICC display profile of the display device. Thus, any CMYK value displayed is converted to L * a * b * values, and furthermore can be converted to display RGB values. Color accuracy also depends on the gamut of the display device.

In addition, second or subsequent display verification may be performed by using a set of CMYK colors. The values for the CMYK color set are converted through the SWOP profile, which is first converted to CIELAB values and then to display RGB values. The SWOP profile is a recommended set of procedures for preparing proofing and printing for web offset publications. Verification of the printing conditions defined in this way ensures that both the creator and the printer of the proof will print the job as it is printed. The CYMK profile is selected in the viewing application and is associated with the ICC display profile of the display device. Thus, any displayed CMYK values can be converted to L * a * b * values and further converted to display RGB values. The resulting RGB patches are displayed, measured and compared with the previous set of measurements from the reference display. The differences in the resulting CIELAB ΔE * ab values determine how well the current display setup simulates standard SWOP printing conditions.

Once the first display device is calibrated, the characterization information is sent to the second or subsequent display device, thereby allowing the gain of the characterization information of the first display device to the second or subsequent display device. Thereafter, the computer readable instructions at the second or subsequent display device can inform the first display device whether the second or subsequent display device can use the characterization information from the first display device.

Referring to FIG. 2, in step 50, characterization information is generated or retrieved from the first display device. In step 52, the characterization information {STF (VD1) (λ)} is then prepared for transmission to the second or subsequent display device. In step 54, the characterization is sent to a second or subsequent display device. The second or subsequent display device determines whether it can use the characterization information from the first display device. In this case, the spectral transfer function of the first video display device matches the spectral transfer function of the second video display device, whereby STF (VD1) (λ) = STF (VD2) (λ). The second or subsequent display device may not have sufficient capabilities to display all the images correctly using the characterization information of the first display device. Thus, in step 56, it is determined whether the second or subsequent display device can use the first display device characterization information. If so, in step 58, the second or subsequent display device can use the characterization information to display subsequent images. If the second or subsequent display cannot use the characterization information, at step 60, the user of the second or subsequent display device is notified of the inability or limit. Thereafter, the second or subsequent user may decide to ignore the notification, and in step 64 subsequent images may be displayed. However, the viewing of such images on an inaccurate display device may result in inaccurate color. If the user does not wish to ignore the notification, the display calibration may be selected using the white point or luminance settings provided by the first display device as described herein. The user of the second or subsequent display device can notify the user of the first display device of this modality. If the second or subsequent display user is unable to duplicate the characterization of the first display device, then at step 66, the user of the first device may modify the characteristics of the first device and thus the second or The user of subsequent devices will be able to view appropriately and accurately as displayed.

In an alternative embodiment, the characterization information (FIG. 3) is attached to the displayed images 72 such that the characterization information is moved along the image file to the second or subsequent display device. Characterization information as well as display characteristics may be associated with the files for transmission to the second or subsequent display devices. The writer of the electronic image or other electronic document uses the computer 72 to generate the computer readable file 72. This file is displayed by the writer for viewing on the display 76, where the display 76 is controlled by the writer's video card 48. The visual appearance of this file is determined by the gamma, white point, and profile on the artist's computer 74. Thus, the writer creates a file with specific display characteristics and characterizations, thus achieving the desired file appearance for the viewer. Thus, the writer's monitor 76 and the writer's video card 78 may have certain settings for display characteristics and characterizations used to determine the appearance of the file. Display characteristics or characteristics are represented as a set of computer readable information shown as display information 70 that may be associated with a file. When a file is sent to the recipient, display or characterization information associated with the file may be sent to the recipient along with the file. Thus, display characteristics or characterizations are associated with the file and are available to any subsequent recipient viewer upon receiving the file from the writer.

The recipient will receive file 72 using recipient computer 80. The file is displayed on the receiver monitor 82 controlled by the receiver video card 84. However, receiver monitor 82 and receiver video card 84 may not necessarily include the appropriate display settings or characterizations that indicate display characteristics intended for the file by the writer. Thus, a recipient viewer who wants to view a file in the same manner as the author intended would not have the appropriate display characteristics or characteristics for the receiver video card or monitor. To remedy this problem, computer readable instructions embodied in the computer readable medium of the recipient computer 80 read the display information 70 associated with the file 72, the video card 84 and the recipient video monitor. The recipient's display settings and profile for 82 can be adjusted to provide the true color of the image as intended by the writer. Thus, the recipient views the image with the appropriate video card and monitor settings, helping the recipient view the same display information as produced by the writer.

Upon receiving the display or characterization information 70, the set of computer readable instructions will determine whether the receiver video card or monitor settings need to be adjusted. If adjustments are needed in accordance with the display information, various adjustment methods may be used. In one embodiment, the adjustments can be performed automatically by simply computer readable instructions of the recipient computer without notifying the recipient. In this case, the computer readable instructions store the original display characteristics of the receiver video card and monitor, adjust them according to the received display information, and restore the original display characteristics when the file is no longer viewed by the receiver. have. Moreover, computer readable instructions notify the recipient viewer that the data on the recipient video card and monitor need to be modified according to the receiving display characteristics, and may ask the recipient viewer if these modifications are desired to be implemented. If so, modifications are implemented and the file with these modifications is viewed.

In another embodiment, the computer readable instructions have instructions for calibrating the display device on a sector by sector. When manufactured, display devices may not have a constant brightness or output over the entire screen area. Thus, the display device is segmented into grating regions, each grating can be calibrated.

Referring to Fig. 6, this aspect of the present invention is described in more detail. In step 100, luminance is selected, and as described herein, a standard calibration and ICC profile for the display device is generated. Thereafter, in step 102, the display device is divided into a plurality of grid regions, such as an 8x8 grid. In step 104, it is determined whether all grating areas have been measured. If all the grating regions have been measured, the lowest luminance of each grating region becomes the maximum target luminance for the display device as determined in step 106. After the target luminance is selected, the grating is presented to the user.

In step 104, if all the grating sectors have not been measured, in step 110, the subsequent grating area to be measured is measured with the display measuring device and generates RGB values. In step 112, RGB values are converted from 16 bits per color format, dithered through an error diffusion process, resulting in an 8 bit result. Subsequently at step 114, the measured grid area is scaled from the grid area to the entire area of the display device. Referring to FIG. 5, an 8x8 grid with illustrated 64 grid regions is shown.

Many of the details set forth herein are intended to facilitate understanding of the invention and are not intended to limit the scope of the invention. Accordingly, the disclosure of embodiments of the invention is intended to illustrate the scope of the invention and is not limiting. The scope of the invention should be limited only to the extent required by the appended claims.

Claims (19)

In a system for generating characterization information for a first display device for use with a second display device, Computer readable media in communication with the first display device; And Initialize lookup table values indicative of default luminance levels of the first display device, measure the output of the first display device according to the initialized lookup table values, and adjust a gray ramp according to the measurement outputs. Determine, map L * of the CIELAB color model of the gray lamp and the first display device, adjust the lookup table values according to the gray ramp mapping and L *, measure RGB color map information, and And a set of computer readable instructions embodied in the computer readable media for determining an ICC profile according to the gray lamp and the RGB color map information. The computer-readable medium of claim 1, wherein the computer readable instructions transmit the ICC profile of the first display device to the second display device, such that the second display device can display images using the ICC profile. Characterization information generation system comprising: instructions for causing a disposition. The computer-readable medium of claim 1, wherein the computer readable instructions determine whether the lookup table values represent a brightness level that exceeds a predetermined level, and wherein the lookup table values exceed a brightness level that exceeds a predetermined level. And instructions for decreasing the brightness level of a first display device. The computer-readable instructions of claim 1, wherein the computer readable instructions determine whether a color temperature at a white point associated with the lookup table values is correct, and modify the lookup table values according to the color temperature of the white point if the color temperature is correct. And characterized in that it comprises instructions. The method of claim 1, wherein the computer readable instructions comprise instructions for determining a gamut map of the first display device and including the gamut map in the ICC color profile. Device. The computer-readable medium of claim 1, wherein the computer readable instructions store the ICC profile in computer readable storage media, subsequently retrieve the stored ICC profile of the first display device, and use the retrieved ICC profile. And verify the retrieved ICC profile by comparing the measured brightness of the display device with the measurements used when initially generating the retrieved ICC profile. The computer readable medium of claim 1, wherein the computer readable instructions generate CMYK information by measuring color patches of the first display device, generate CMYK ICC profile information from the color patch measurements, and And instructions for determining an L * a * b * -CMYK-L * a * b * table from the measurements indicative of characterization information. The computer-readable medium of claim 1, wherein the readable instructions associate the characterization information with an image file, and transmit the image file and the associated characterization information to the second display device, thereby characterizing information of the first display device. Is transmitted together with the image information to be displayed. In a system for using characterization information from a first display device, Computer readable media in communication with the second display device; And Receive characterization information indicative of color characterization of the first display device, determine whether the second display device can use the characterization information, and display the characterization information for displaying images on the second display device. A system for utilizing characterization information comprising a set of computer readable instructions embodied in the computer readable media for use. 10. The computer-readable medium of claim 9, wherein the computer readable instructions include instructions to modify characteristics of the second display device when the second display device is unable to use the received characterization information of the first display device. A system for using the characterization information. 10. The computer-readable medium of claim 9, wherein the computer readable instructions generate a notification to a user when the second display device cannot use the reception characterization information, such that the second display device may use the reception characterization information. And instructions that the user is notified of being absent. 12. The computer-readable medium of claim 11, wherein the computer readable instructions calibrate the second display device when the second display device is not available and use the characterization information after the second display device is calibrated. And instructions for determining if it can be. In a system for calibrating a first display device having at least one lookup table, Computer readable media in communication with the first display device; And Initialize at least one lookup table of the first display device to default values according to a predetermined white point, measure the first display device output using a display measurement device, until desired white point values are obtained Modify the at least one lookup table according to the measured output, generate a gray lamp by mapping gray values from the first display device measurements to L * of a CIELAB color model, and at least one lookup table Adjust the color depth; measure an RGB color volume of the first display device; determine a gamut map of the first display device; and measure the measured RGB color volume, the gray lamp, the at least one lookup table, and the To generate the ICC color profile according to the gamut map A first display device calibration system comprising a set of computer readable instructions embodied in computer readable media. 14. The computer program product of claim 13, wherein the computer readable instructions associate the ICC color profile with a particular job and store the ICC profile associated with the particular job for subsequent retrieval, such that the particular job is subsequently added. Or instructions that may be subsequently used by the ICC profile when retrieved for inspection. The computer-readable medium of claim 13, wherein the computer readable instructions send the ICC color profile to a second display device, such that the second display device uses the ICC color profile of the first display device for display of images. And instructions to enable the first display device calibration system. The computer-readable medium of claim 13, wherein the computer readable instructions store the ICC color profile of the first display device, retrieve the ICC color profile of the first display device, and gray colors on the first display device. Display the set, measure the first display device with the display measurement device, and compare the measured values from the display measurement device with the ICC color profile to validate the retrieved ICC profile of the first display device. And a command to: a first display device calibration system. The computer-readable medium of claim 13, wherein the computer readable instructions store the ICC color profile of the first display device, retrieve the ICC color profile of the first display device, and at least one using the retrieved ICC color profile. Display a CMYK image of the device, measure color patches with the display measurement device according to the displayed CMYK image, convert the measurements from the color patch measurements into RGB information, and display the display according to the converted RGB information. Measuring color patches, and comparing the measurements of the CMYK color patches with the RGB color patches to verify the retrieved ICC color profile. In a system for generating characterization information for a first display device for use with a second display device, Computer readable media; And Initialize lookup table values of the first display device; Segment the first display device into a plurality of grating regions; Measure at least one output of the grating regions; Determine a gray lamp according to the measurements; Map L * of the gray lamp and the CIELAB color model; Adjust the lookup table values according to the gray ramp mapping; And a set of computer readable instructions embodied in the computer readable media for determining an ICC color profile according to the gray lamp and the adjusted lookup table values. The set of computer readable instructions includes instructions for measuring an RGB color map for at least one of the grid regions, and determining an ICC color profile according to the RGB color map for at least one of the grid regions. Characterized information generation system, characterized in that.

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