JP2004056574A - Image processor, image processing method and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor capable of performing color matching with high accuracy by calculating color matching accuracy by objective judgement standards based on a human visual characteristic, also verifying the color matching by the objective judgement standards based on the human visual characteristic in each of different color conversion contents and appropriately updating a profile and to provide its method and its medium. <P>SOLUTION: In this present invention, a printer profile corresponding to a color conversion method is used to prepare image data of color patches, and an image output device 3 uses the image data of the color patches and prints the color patches on a recording medium and outputs the recording medium with the color patches printed thereon. A colorimeter 20 measures the color of each of the color patches recorded on the recording medium, and matching accuracy calculating part 8 uses the measurement data of measurement results to calculate the accuracy (CRI) of color matching. A matching accuracy determining part 9 compares the CRI with a preset threshold TH, determines whether the accuracy of the color matching is good or bad and notifies determination results. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image processing device, an image processing method, and a storage medium.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, with the spread of personal computers, an image is input as electronic data using an image input device such as a digital camera or a color scanner, and the image is displayed and confirmed using an image display device such as a CRT or an LCD. Editing, processing, correction, and the like are performed according to the application, and an image is output by an image output device such as a color printer. Recently, the use of directly outputting an image captured by a digital camera to a color printer without displaying it on a color monitor has been increasing. Further, there is a usage method that does not require an image input device, in which a CG image created on a computer is output by a color printer.
[0003]
As described above, when an image is handled between different image input / output devices such as a digital camera, a color scanner, a color monitor, and a color printer, the color reproduction characteristics and the color reproduction range of each device are different. Thus, a technique called a color management system (hereinafter, CMS) for matching color reproduction between different image processing apparatuses has appeared. The CMS includes a device profile describing the color reproduction characteristics of each image processing apparatus, a color matching method for performing color conversion, and the like. In order to realize consistent color reproduction between the image processing apparatuses, it is necessary to improve the accuracy of the device profile and the color matching method, and accordingly, the device profile is appropriately updated.
[0004]
Here, as the color conversion method, there are a plurality of methods according to the content of the image, the purpose of the color conversion, and the like. For example, a method of matching the monitor display with the printer output, a method of converting the print output to be desirable, and a method of converting the print output as vivid as possible and using the printer's color gamut as widely as possible. there were. Further, among the above color conversion methods, there is a color conversion method using a corresponding color in an output color signal corresponding to an input color signal.
[0005]
[Problems to be solved by the invention]
However, in the above-described conventional example, the updating of the device profile is not always performed in an appropriate case.For example, in the case of matching the monitor with the printer, for example, in the case of matching between the display color on the color monitor and the color printer, Compared with the output result, it is performed when it is determined that it is necessary, and it is not clear whether the profile should be updated or not. Furthermore, the judgment criteria were not quantified because they were subjective and ambiguous in that judgments were made based on human appearance. Japanese Patent Laying-Open No. 11-232073 discloses updating of a device profile for improving matching accuracy between color image processing apparatuses, but also discloses updating of a device profile visually by a user. The criteria for updating were not clear and not quantified.
[0006]
On the other hand, in some cases, the determination as to whether or not to update may be made objectively. However, in the case of the monitor matching as described above, attention has simply been paid to the color difference between the colorimetric value of the color monitor display color and the colorimetric value of the color output color of the color printer. Therefore, in a color conversion method for matching a light source color displayed on a color monitor or the like with an object color output on a color printer or the like, the appearance of each color is different, and even if the colorimetric values are matched, the same color is obtained. There is a problem that the accuracy of color conversion cannot be accurately determined because a criterion corresponding to human color appearance is not used. Further, in the case of a method of converting a printed matter preferably, there is a problem that it is difficult to quantify the subjective content of preference, and it is not possible to accurately determine the accuracy of color conversion.
[0007]
The present invention has been made in view of the above problems, and has as its object to provide an image processing apparatus, an image processing method, and a storage medium that require color matching accuracy based on objective judgment criteria based on human visual characteristics. I do.
[0008]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem, and it is possible to accurately verify color conversion accuracy for each color conversion content, appropriately update a device profile, and perform image processing that can perform color conversion with high accuracy. An object is to provide an apparatus, a method thereof, and a medium therefor.
[0009]
[Means for Solving the Problems]
In order to achieve an object of the present invention, for example, an image processing apparatus of the present invention has the following configuration.
[0010]
That is, data of a first color group including at least one or more colors and each color obtained by outputting each color of the first color group by the image output device, wherein each color is the first color. Storage holding means for storing and holding each color of the color group and data of a second color group constituted by each color having a predetermined relationship in association with each other;
Data indicating a color group obtained by outputting the input color group by the image output device is input from the outside, and the data and the correspondence corresponding to the input color group stored and held in the storage unit are stored. Calculation means for calculating a lightness error, a saturation error, and a hue error using the data of the color group and calculating a color reproduction index of color matching using these errors;
It is characterized by having.
[0011]
Also preferably,
The image output device, a profile storage holding unit that stores and holds a profile of each device including an image display device,
Based on the average value, a notification unit that determines whether to update the profile of any one of the devices stored and held in the profile storage unit and notifies the determination result is provided. Features.
[0012]
Preferably, the apparatus further comprises updating means for updating any one of the profiles of the devices.
[0013]
Preferably, the apparatus further comprises a transmission unit for transmitting the profile updated by the updating unit to an external device.
[0014]
In order to achieve the object of the present invention, for example, an image processing method of the present invention has the following configuration.
[0015]
That is, data of a first color group including at least one or more colors and each color obtained by outputting each color of the first color group by the image output device, wherein each color is the first color. Each color of the color group and data of a second color group composed of each color having a predetermined relationship are stored in a memory in association with each other,
Data indicating a color group obtained by outputting the input input color group by the image output device is externally input, and the data and a corresponding color group corresponding to the input color group stored and held in the memory , An error of lightness, an error of saturation, and an error of hue are obtained, and further, a color reproduction index of color matching is obtained by using these errors.
[0016]
Also preferably,
The image output device, a profile of each device including an image display device is stored and held in a memory,
A notification step of determining whether to update the profile of any of the devices stored in the memory based on the average value, and reporting a determination result. .
[0017]
Preferably, the apparatus further comprises an updating step of updating any one of the profiles of the devices.
[0018]
Preferably, the method further comprises a transmitting step of transmitting the profile updated in the updating step to an external device.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail according to preferred embodiments with reference to the accompanying drawings.
[0020]
[First Embodiment]
<Basic configuration of image processing device>
FIG. 1 is a block diagram illustrating a functional configuration of the image processing apparatus according to the present embodiment and peripheral devices thereof. Reference numeral 1 denotes an image processing apparatus main body, 2 denotes an image display device, which is constituted by a CRT, an LCD, or the like, and displays an image. An image output device 3 prints an image on an image recording medium such as paper or OHP. In the present embodiment, the image output device 3 is treated as a printer. However, the device is not limited to a printer as long as it has a function of printing an image on the image recording medium.
[0021]
Reference numeral 4 denotes an interface (I / F) unit for connecting the image display device 2 to the image processing device 1, and 5 denotes a color input from the image input device 17, a color displayed on the image display device 2, and an image output device 3. A color matching processing unit 6 for performing color matching with the color output by the image processing unit 6; and an image processing unit 6 for performing various image processing such as gradation conversion processing on the image output to the image output device 3.
[0022]
Reference numeral 7 denotes a corresponding color / permissible value storage unit for each color conversion in which a corresponding color for each color conversion and its permissible value (the details of the corresponding color for each color conversion and its permissible value will be described later) are stored. A color matching accuracy calculating unit 9 for obtaining the accuracy of color matching by the method; a color matching accuracy determining unit 9 for determining the color matching accuracy using the result of the accuracy calculated by the color matching accuracy calculating unit 8; A profile creating / updating unit 11 for creating and updating device profiles to be used (profiles such as a printer profile, a monitor profile, and a scanner / digital camera profile to be described later). A user inputs various instructions to the image processing apparatus 1 by the user. Operation unit.
[0023]
12, a paper setting unit for setting the type of output paper used in the image output device 3, 13 an I / F unit for connecting the image output device 3 to the image processing device 1, and 14 a temporary unit for performing data processing. A data buffer 15 for storing data, a monitor profile storage unit 15 for storing a monitor profile of the image display device 2 or the like for each color conversion method, and 16 a printer profile for the image output device 3 or the like for each color conversion method. A printer profile storage unit 17, an image input device such as a scanner or a digital camera capable of inputting an image as electronic data to the image processing device 1, and 18 an image input device 17 for connecting the image input device 17 to the image processing device 1 An I / F unit 19 is a scanner that stores a profile of the image input device 17 such as a scanner or a digital camera for each color conversion method. - a digital camera profile storage unit.
[0024]
Reference numeral 20 denotes a colorimeter for measuring the color of each color patch printed on the recording medium output from the image output device 3. Reference numeral 21 denotes an I / F unit for connecting the colorimeter 20 to the image processing apparatus 1.
[0025]
<Overall processing>
In the following, a color patch according to the printer profile according to the specified color conversion is output to the image output device 3, the output color is read by the result measured by the colorimeter 20, and the captured color is designated as the designated color. A difference (corresponding to the difference will be described later, and this difference is referred to as color matching accuracy) from the corresponding color corresponding to the color conversion is determined, and whether the printer profile should be updated according to the accuracy is determined. An image processing method for presenting such information will be described. In the following, a printer profile is used as a profile to be updated. However, the present invention is not limited to this. For example, a monitor profile may be used.
[0026]
FIG. 2 is a flowchart of the main processing of the image processing. FIG. 8 shows a configuration example of a GUI displayed on the image display device 2 for inputting execution of each process described later. Hereinafter, a process of obtaining the accuracy of color matching and creating and updating a printer profile according to the obtained accuracy will be described with reference to FIGS.
[0027]
First, the user designates and selects one of the check buttons 814a, 814b, and 814c using the operation unit 11 (the color conversion method corresponding to the black circle is the selected color conversion method). Thereby, the accuracy of the color matching in the selected color conversion method is obtained below. The selection of the color conversion method is not limited to these three. Therefore, in step S200, the selected color conversion method is set as one to be used in the following processing.
[0028]
Next, in step S201, pressing of the patch output button 804 by the user using the operation unit 11 is detected, and the image of the color patch is obtained from the printer profile storage unit 16 using the printer profile corresponding to the color conversion method set in step S200. Data is created and output to the data buffer 4. The image output device 3 prints a color patch on a recording medium such as paper or OHP using the image data of the color patch, and outputs it. In the present embodiment, six color patches of R, G, B, C, M, and Y are used as color patches, but the number is not limited to this.
[0029]
Next, in step S202, the color of each color patch recorded on the recording medium by the colorimeter 20 is measured. Next, in step S203, pressing of the measurement data read button 805 by the user using the operation unit 11 is detected, and the measurement data Dn (where n is an index indicating each color (patch), Then, 1 ≦ n ≦ 6) is input to the data buffer 14. In this embodiment, the measurement result is a CIELAB value determined by CIE (International Commission on Illumination).
[0030]
Next, in step S204, pressing of the accuracy calculation button 806 by the user using the operation unit 11 is detected, and the matching accuracy calculation unit 8 calculates the accuracy of color matching using the measurement data D. Although details of the process in step S204 will be described later, in this step, a color reproduction index CRI of color matching is obtained as the accuracy of color matching.
[0031]
Next, in step S205, the matching accuracy determination section 9 compares the color reproduction index CRI with a preset threshold TH to determine whether the color matching accuracy is good or not. The result of the determination is displayed in an area 807. In the area 807, a numerical value indicating the accuracy of the color matching and character information indicating whether or not the accuracy is acceptable are displayed. The details of the determination processing in this step will be described later. Next, in step S206, the matching accuracy determination section 9 determines whether or not the judgment result is acceptable (determined by comparing the color reproduction index CRI with the threshold value TH).
[0032]
If not, the printer profile should be updated. Therefore, in step S207, the press of the button 813 for instructing the update of the device profile is accepted, and the update can be performed. If it is detected that the user has pressed the profile update button 813 using the operation unit 11, the process proceeds to step S208, where the profile creation / update unit 10 creates the latest printer profile. 16 is updated to the created latest printer profile. The details of the latest printer profile creation process will be described later.
[0033]
In step S209, it is determined again whether or not the user has pressed the re-verification button 815 using the operation unit 11 to perform the color matching accuracy using the updated printer profile. If so, the process proceeds to step S200; otherwise, the process ends.
[0034]
<Calculation of color matching accuracy>
FIG. 3 is a flowchart showing details of the process in which the color matching accuracy calculation section 8 calculates the accuracy of color matching in step S204. The details of the process for obtaining the accuracy of color matching will be described below with reference to the flowchart.
[0035]
First, in step S301, the number of colors n for calculating color matching accuracy is initialized to one. Next, in step S302, the nth corresponding color data Pn and the permissible value data Tn (1 ≦ n) registered in the table corresponding to the color conversion method selected and set in step S200 from the corresponding color / permissible value storage unit 7 ≦ 6).
[0036]
FIG. 5 shows a configuration example of a table for each color conversion method. Each table is provided for each color conversion method, and is used to realize different color reproducibility. For example, the table 1 is used for a first color reproduction that performs visually faithful color reproduction on the image display device 2.
[0037]
In each table, corresponding color data Pn and allowable value data Tn corresponding to patches of six colors are registered. Other items in the table will be described with reference to FIG. FIG. 4 shows an a * b * plane in the CIELAB color space. The front side of the drawing is defined as a positive L direction, and the back direction of the drawing is defined as a negative L direction.
[0038]
The original color ORn (○) indicates, for example, the color displayed on the image display device 2, and the corresponding color Pn (例 え ば) is output from the image output device 3 that performs the best color matching with the original color ORn, for example. Indicates the color Pn to be used. That is, when the original color is recorded on the image recording medium by the image output device 3 and the recorded color is judged to be the same as the original color by subjective evaluation, the recorded color corresponds to the original color. Corresponding color.
[0039]
TnLp and TnLm indicate allowable ranges (TnLp is a plus-side allowable value and TnLm is a minus-side allowable value) when the original color ORn and the corresponding color Pn are matched with respect to saturation. TnCp and TnCm indicate allowable ranges (TnCp is a positive side allowable value, TnCm is a negative side allowable value) when the original color ORn and the corresponding color Pn are matched with respect to saturation, and TnHp and TnHm are the same. , The allowable range where the original color ORn and the corresponding color Pn match with respect to the hue (TnHp is a plus side allowable value, and TnHm is a minus side allowable value).
[0040]
The corresponding color Pn and the permissible values TnLp, TnLm, TnCp, TnCm, TnHp, TnHm corresponding to the original color ORn are determined in advance by a subjective evaluation experiment between the monitor display color and the print color, as shown in FIG. It is assumed that the corresponding table data is stored in the corresponding color / permissible value storage unit 7 for each color reproduction.
[0041]
Of course, it is needless to say that the corresponding color and the allowable value may be set for each image output device or each output sheet, and may be appropriately used. Here, PnL, PnC, and PnH in FIG. 5 are colorimetric values LCH of Pn in the polar coordinate system, and are converted from CIELAB values using the following equations (1) to (3).
[0042]
L * = L * (1)
Cab * = √ ((a *) × (a *) + (b *) × (b *)) (2)
Hab = arctan (b * / a *) (3)
Returning to FIG. 3, in step S303, of the measurement data D written in the data buffer 14 in step S203, the n-th measurement data Dn is read from the data buffer 14, and the above equations (1) to (3) are calculated. Is used to calculate the polar coordinate system color values DnL, DnC, and DnH. In step S304, the brightness DnL of the n-th color patch is compared with the brightness PnL of the n-th corresponding point. If DnL ≧ PnL, the process proceeds to step S305, and the brightness accuracy Le is calculated.
Le = (DnL-PnL) / TnLp
Is calculated. That is, a value obtained by normalizing the difference between the brightness DnL of the nth color patch and the brightness PnL of the nth corresponding point with the allowable value TnLp on the plus side of the brightness is calculated. Therefore, only when the value Le obtained by this calculation is 0 ≦ Le ≦ 1, it is permissible that the brightness DnL of the nth color patch matches the brightness PnL of the nth corresponding point.
[0043]
On the other hand, if DnL <PnL as a result of the comparison in step S304, the process proceeds to step S306, and the brightness accuracy Le is adjusted.
Le = (PnL-DnL) / TnLm
Is calculated. That is, only when the value Le calculated by this calculation is 0 ≦ Le ≦ 1, it is acceptable that the brightness DnL of the n-th color patch matches the brightness PnL of the n-th corresponding point.
[0044]
In step S307, the saturation DnC of the n-th color patch is compared with the saturation PnC of the n-th corresponding point. If DnC ≧ PnC, the process proceeds to step S308, and the saturation accuracy Ce is calculated.
Ce = (DnC-PnC) / TnCp
Is calculated. That is, a value obtained by normalizing the difference between the saturation DnC of the nth color patch and the saturation PnC of the nth corresponding point by the allowable value TnCp on the plus side of the saturation is calculated. Therefore, only when the value Ce by this calculation is 0 ≦ Ce ≦ 1, it is acceptable that the saturation DnC of the nth color patch matches the saturation PnC of the nth corresponding point.
[0045]
On the other hand, if DnC <PnC as a result of the comparison in step S307, the process proceeds to step S309, in which the saturation accuracy Ce is reduced.
Ce = (PnC-DnC) / TnCm
Is calculated. That is, only when the value Ce by this calculation is 0 ≦ Ce ≦ 1, it is acceptable that the saturation DnC of the n-th color patch matches the saturation PnC of the n-th corresponding point.
[0046]
In step S310, the hue DnH of the n-th color patch is compared with the hue PnH of the n-th corresponding point, and if DnH ≧ PnH, the process proceeds to step S311 to set the hue accuracy He to
He = (DnH-PnH) / TnHp
Is calculated. That is, a value obtained by normalizing the difference between the hue DnH of the n-th color patch and the hue PnH of the n-th corresponding point by the allowable value TnHp on the plus side of the hue is calculated. Therefore, only when the value He by this calculation is 0 ≦ He ≦ 1, it is acceptable that the hue DnH of the n-th color patch matches the hue PnH of the n-th corresponding point.
[0047]
On the other hand, if DnH <PnH as a result of the comparison in step S310, the process proceeds to step S312, and the hue accuracy He is reduced.
He = (PnH-DnH) / TnHm
Is calculated. That is, only when the value He by this calculation is 0 ≦ He ≦ 1, it is acceptable that the hue DnH of the n-th color patch matches the hue PnH of the n-th corresponding point.
[0048]
As described above, Le, Ce, and He obtained by the above processing are errors when the maximum allowable value is set to 1 when matching is seen by a human, and therefore, for each of the lightness direction, the saturation direction, and the hue direction. It can be treated as a value equivalent to the characteristics of the human eye.
[0049]
Next, in step S313, using the error Le in the lightness direction, the error Ce in the saturation direction, and the error He in the hue direction, a color reproduction index CRIn, which is an evaluation amount representing the degree of color matching when viewed by a human, is calculated as follows. Calculate based on the formula.
[0050]
CRIn = √ (Le × Le + Ce × Ce + He × He)
This CRIn indicates the accuracy of color matching between the color of the nth color patch and the nth corresponding color. Next, in step S314, the obtained CRIn is written to the data buffer 14. In step S315, all the above processes are performed on all the color patches, it is determined whether or not CRIn has been obtained for all of the color patches (whether or not n = 6). If is obtained, the process shown in FIG. 3 is terminated, and the process proceeds to step S205. On the other hand, if n <6, the process proceeds to step S316, n is updated by adding 1, and the process from step S302 is performed.
<Color matching accuracy determination>
FIG. 6 is a flowchart of a process in which the color matching accuracy determination unit 9 determines whether the color matching accuracy is good or not using the CRIn in the above step S205.
[0051]
First, in step S601, variables CRIs and n used below are initialized to 0 and 1, respectively. Then, in step S602, CRIn is read from the data buffer 14, and added to the variable CRIs in step S603. In step S604, it is determined whether or not CRIn for all n has been added to CRIs (whether or not n = 6). If n <6, the process proceeds to step S609; Is updated by adding 1, to Steps S602 and S603.
[0052]
On the other hand, if n = 6, the process proceeds to step S605, and the value obtained by dividing CRIs by n (= 6) is substituted for the variable CRI. That is, the variable CRI indicates an average value of all CRIns, and this embodiment uses the CRI as a color reproduction index. In step S606, the CRI is compared with a predetermined threshold value TH, and if CRI <TH, that is, the average value of the error in the lightness direction, the error in the saturation direction, and the error in the hue direction for all the color patches is determined to be a predetermined value. If it is smaller than the value, the error between the color of each patch and its corresponding color is small (the degree of color matching when viewed by a human is high), so the process proceeds to step S607, and the result of the accuracy determination is determined. "Passed". That is, “pass” is displayed in the area for displaying the determination result in the area 807, and the pass is notified.
[0053]
On the other hand, when CRI ≧ TH, that is, when the average value of the error in the lightness direction, the error in the saturation direction, and the error in the hue direction for all the color patches is equal to or more than a predetermined value, the color of each patch and its corresponding Since the error with the corresponding color is large (the degree of color matching when viewed by a human is low), the process proceeds to step S608, and the result of the accuracy determination is “fail”. That is, “fail” is displayed in the area for displaying the determination result in the area 807 to notify the failure. In both cases of step S607 and step S608, the obtained color reproduction index CRI is displayed in the area for displaying the accuracy in the area 807.
[0054]
In the present embodiment, the notification method of the accuracy determination result is displayed as characters such as “pass” and “fail”. However, the present invention is not limited to this. For example, “pass”, “ It may be expressed as an image representing “fail” or a sound.
[0055]
Although not shown in the flowchart, when the user presses the detail button 808 using the operation unit 11, the GUI illustrated in FIG. 9 is displayed on the image display device 2. The GUI in FIG. 7 displays matching accuracy, that is, CRIn, for each color of each patch.
[0056]
<Latest profile creation>
FIG. 7 is a flowchart showing the details of the process in which the profile creation / update unit 10 updates the printer profile to the latest one in step S208. The process of updating the printer profile to the latest one will be described below in detail with reference to the flowchart.
[0057]
In step S701, it is detected that the user has pressed the patch output button 809 using the operation unit 11, and in step S200, data of a color patch for profile creation corresponding to the color selection method selected and set in step S200 is created. Output to 3. The image output device 3 prints and outputs a color patch on a recording medium based on the data. Although the number of colors of the color patches to be output is not particularly limited, for example, 729 color patches of a combination of 9 steps for each color of RGB are output.
[0058]
In step S702, the color of each color patch recorded on the recording medium is measured by the colorimeter 20. When it is detected in step S703 that the reading of the measurement data read 810 is detected, the measurement data, which is the measurement result, is stored in the data buffer 14. To enter. In this embodiment, the measurement result is a CIELAB value determined by CIE (International Commission on Illumination). Next, in step S203, the press of the measurement data read button 805 by the user using the operation unit 11 is detected, and the measurement data D is written to the data buffer 14.
[0059]
In step S704, pressing of the profile creation button 811 by the user using the operation unit 11 is detected, and a printer profile corresponding to the color conversion method selected and set in step S200 is created according to a predetermined format. The user can also input a desired profile name in the file name window 812 using the operation unit 11.
[0060]
As described above, by verifying the accuracy of the color matching using the corresponding color Pn corresponding to the original color OR and the allowable range Tn, the color matching accuracy based on an objective criterion based on human visual characteristics. Can be verified and the profile can be updated appropriately.
[0061]
[Second embodiment]
FIG. 10 shows the functional configuration of the image processing apparatus according to the present embodiment, and also shows the configuration with peripheral devices. Reference numeral 1001 denotes a main body of the image processing apparatus according to the present embodiment, to which a sensor (sensor unit 1004) for performing color measurement can be connected. The image processing apparatus according to the present embodiment is a portable (portable) image processing apparatus such as a PDA or a notebook computer.
[0062]
An external image processing apparatus 1002 connected to the image processing apparatus 1001 is generally a desktop computer such as a PC or a workstation, and holds various device profiles similarly to the image processing apparatus 1001. The image processing apparatus 1001 of the present embodiment transmits a new profile created by performing the same processing as in the first embodiment to the external image processing apparatus 1002. The image processing apparatus 1002 receives the transmitted profile and updates the received profile. Hereinafter, the image processing apparatus 1001 and the processing performed by the image processing apparatus 1001 will be described. In the following, a profile to be updated will be described as a printer profile, but the present invention is not limited to this. For example, a monitor profile may be used.
[0063]
An image output apparatus 1003 prints an image on an image recording medium such as paper or OHP. In this embodiment, the image output device 1003 is treated as a printer, but is not limited to a printer as long as it has a function of printing an image on the image recording medium. Reference numeral 1004 denotes the sensor unit, and reference numeral 1005 denotes a communication interface unit for performing data communication between the image processing apparatus 1001 and the image processing apparatus 1002.
[0064]
Reference numeral 1006 denotes a measurement data holding unit 1006 and 1007 for holding measurement data by the sensor unit 1004. Corresponding colors for each color conversion and their permissible values (the details of the corresponding colors for each color conversion and their permissible values will be described later) are stored. A color / permissible value storage unit corresponding to each color conversion, 1008 is a color matching accuracy calculation unit for obtaining color matching accuracy, and 1009 is a color matching accuracy determination using the accuracy result calculated by the color matching accuracy calculation unit 1008. A color matching accuracy discriminating unit 1010 is a profile creating / updating unit that creates and updates a device profile (a profile such as a printer profile, a monitor profile, and a scanner / digital camera profile) used for color matching.
[0065]
Reference numeral 1011 denotes an operation / display unit that displays images and character information and can input various instructions in a touch panel format. Reference numeral 1012 denotes a sensor control unit 1012 that controls the sensor unit 1004. A data buffer 1014 for temporarily storing data, a monitor profile storage unit 1014 storing a monitor profile for each color conversion method, and a printer 1015 storing a printer profile for the image output device 1003 or the like for each color conversion method. This is a profile storage unit.
[0066]
<Overall processing>
FIG. 11 is a flowchart of main processing of image processing performed by the image processing apparatus according to the present embodiment having the above configuration. In the flowchart shown in FIG. 11, each process from step S1101 to step S1109 is almost the same as each process from step S200 to step S209, and in step S1102, in the present embodiment, The difference is that the color of the color patch on the recording medium is measured using the sensor unit 1004. Therefore, description of each process from step S1100 to step S1109 will be omitted. In the present embodiment, it is assumed that the screen displayed on the operation / display unit 1011 displays the GUI shown in FIG.
[0067]
In step S1110, the printer profile newly created in step S1108 is transmitted to the image processing apparatus 1002 via the communication interface unit 1005. The image processing apparatus 1002 updates the held printer profile to the transmitted printer profile.
[0068]
As described above, by using the handy-type image processing device with the sensor unit for color measurement, it is possible to use the image processing device 1002 to perform color matching accuracy based on objective judgment criteria based on human visual characteristics. It is possible to easily perform the verification of the image processing and appropriately update the profile. The image processing apparatus 1001 is held by a service person or the like, and the image processing apparatus 1002 can be externally provided to the image processing apparatus 1002 based on the human visual characteristics. It is possible to verify the color matching accuracy based on a basic criterion, transmit the result of updating the profile as appropriate, and update the profile held by the image processing apparatus 1002.
[0069]
[Third Embodiment]
FIG. 12 shows a functional configuration of a server-side image processing apparatus and a client-side image processing apparatus (hereinafter, an image processing server). The image processing apparatus according to the present embodiment transmits the measurement data to the image processing server, receives the latest profile created by the image processing server using the measurement data, and updates the received profile. On the other hand, the image processing server obtains the color matching accuracy using the received measurement data, and if the accuracy is not acceptable, creates a new profile and transmits it to the image processing device. Hereinafter, the image processing apparatus and the image processing server and the processing performed by them will be described. In the following, a profile to be updated will be described as a printer profile, but the present invention is not limited to this. For example, a monitor profile may be used.
[0070]
Reference numeral 1201 denotes an image processing server having the following configuration. Reference numeral 1204 denotes a communication interface unit used for performing data communication between the image processing server 1201 and the image processing device 1202; 1205, a measurement data storage unit for storing measurement data transmitted from the image processing device 1202; The corresponding color / permissible value storage unit for each color conversion, in which the corresponding color and its permissible value (details of the corresponding color for each color conversion and its permissible value will be described later) are stored. A matching accuracy calculating unit 1209 performs a color matching accuracy determination using the result of the accuracy calculated by the color matching accuracy calculating unit 1208. A color matching accuracy determining unit 1206 includes a device profile (printer profile, described later) used for color matching. Monitor profile, scanner / digital camera profile A profile generator of making profile) such as yl.
[0071]
Reference numeral 1210 denotes an operation / display unit capable of displaying images and character information and inputting various instructions in a touch panel format, 1212 a data buffer for temporarily storing data for data processing, and 1213 a monitor. A monitor profile storage unit 1210 stores a profile for each color conversion method. A printer profile storage unit 1214 stores a printer profile of the image output device 1203 or the like for each color conversion method.
[0072]
An image processing apparatus 1202 is connected to the image processing server 1201 via a network such as the Internet or a LAN. An image output device 1203 is connected to the image processing device 1202 via the I / F unit 1215, and prints an image on an image recording medium such as paper or OHP. Reference numeral 1216 denotes a color matching processing unit which performs a color matching process between a color displayed on the image display device 1226 and a color output from the image output device 1203. Reference numeral 1217 denotes a gradation conversion process for an image output to the image output device 1203. An image processing unit that performs various image processing such as.
[0073]
Reference numeral 1218 denotes a paper setting unit for setting the type of output paper used in the image output apparatus 1203. Reference numeral 1219 denotes a profile update for updating a device profile (a profile such as a printer profile, a monitor profile, and a scanner / digital camera profile described later) used for color matching. Department. Reference numeral 1220 denotes an operation / display unit capable of displaying images and character information and inputting various instructions in a touch panel format, 1221 a communication interface unit for performing data communication with the image processing server 1201, 1222 an image A monitor profile storage unit that stores a monitor profile of the display device 1226 for each color conversion method, and a printer profile storage unit 1223 that stores printer profiles of the image output device 1203 and the like for each color conversion method.
[0074]
Reference numeral 1224 denotes an image buffer for temporarily storing image data to be output to the image output device 1203. Reference numeral 1225 denotes an I / F unit for connecting to the image display device 1226. Reference numeral 1226 denotes an image display device, which is configured by a CRT, an LCD, or the like, and displays an image. Reference numeral 1228 denotes a colorimeter which measures the color of each color patch printed on the recording medium output from the image output device 1203. Reference numeral 1227 denotes an I / F unit for connecting the colorimeter 1228 to the image processing device 1202.
[0075]
<Overall processing>
FIG. 13 is a flowchart of main processing performed by the image processing apparatus and the image processing server having the above configuration. The processes performed by the image processing apparatus 1202 from step S1301 to step S1303 are the same as the processes from step S200 to step S202, and thus description thereof is omitted. In the present embodiment, it is assumed that the screen displayed on the operation / display units 1220 and 1210 displays the GUI shown in FIG.
[0076]
In step S1304, the data measured by the colorimeter 1228 is transmitted to the image processing server 1201 via the communication interface unit 1202. When the image processing server 1201 receives the measurement data in step S1351, it registers it in the measurement data storage unit 1205 in step S1352, and writes the measurement data to the data buffer 1212 in step S1353.
[0077]
Each process from step S1354 to step S1358 is almost the same as each process from step S204 to step S208, except that the latest printer profile is created by the profile creation unit 1206. Therefore, description of each process from step S1354 to step S1358 will be omitted. Next, in step S1359, a printer profile corresponding to the color conversion method selected and set in step S1301 is registered as the latest printer profile in the printer profile storage unit 1214. In step S1360, the latest printer profile created via the communication interface unit 1204 is transmitted to the image processing apparatus 1202.
[0078]
In step S1305, the image processing apparatus 1202 receives the measurement data. In step S1306, the profile updating unit 1219 converts the printer profile according to the color conversion method selected and set in step S1301 in the printer profile storage unit 1223 into the received printer profile. Update.
[0079]
In step S1361, the image processing server 1201 transmits data indicating the result of the color matching (data indicating whether the color matching has passed or failed, and data indicating the obtained accuracy) via the communication interface unit 1204, and the image processing apparatus 1202 Receives these data in step S1307.
[0080]
As described above, even when the image output device and the device (image processing server) for obtaining the accuracy of color matching are present at different positions (particularly at remote positions), an objective judgment criterion based on human visual characteristics. Color matching accuracy. It is easy to update the profile appropriately.
[0081]
[Fourth embodiment]
In the above embodiment, the profile is updated by updating the profile (printer profile) of the image output device. However, the profile may be updated by updating the profile of the image input device or the profile (monitor profile) of the image display device. That is, in order to enhance the accuracy of color matching, the profile of the image output device, the image input device, or the image display device may be appropriately updated. Further, instead of updating the profile, the color matching method may be changed. Of course, it goes without saying that the update of the profile and the change of the color matching method may be combined.
[0082]
In this case, a button for updating a monitor profile and the like other than the printer profile is provided.
[0083]
In the above embodiment, the color reproduction index CRI is obtained by calculating the color reproduction index CRIn of each color patch using the lightness error, the saturation error, and the hue error, and further calculating the average value of all CRIn. Although the reproduction index CRI was determined, the present invention is not limited to this. In addition, for example, for each color patch, the average value of the lightness error, the average value of the saturation error, and the average value of the hue error are obtained, and a threshold value is set for each of the average values. May be performed, and a pass / fail judgment may be made.
[0084]
[Fifth Embodiment]
In the above embodiment, the accuracy of color matching between the corresponding color corresponding to the color displayed on the image display device and the color obtained by outputting the color displayed on the image display device to the image output device is required. However, in addition, for example, connecting the image processing device and the image output device, if the color output by the image output device does not match the user's preference, input the desired color of the user to the image processing device, Color matching between a color corresponding to the input color and a color obtained by measuring the color output by the image output device with a colorimeter may be obtained. Then, depending on the accuracy of the color matching, the result of the pass / fail of the accuracy may be displayed on the GUI as described in the first embodiment, and the profile of the printer may be performed.
[0085]
As described above, when the color displayed and output by the image output device or the image display device is not the color desired by the user, the user is allowed to input the desired color, and The accuracy of color matching with the displayed and output colors may be determined, and the profile may be updated according to the result.
[0086]
As a method of selecting a corresponding color corresponding to a desired color, for example, a color that matches the desired color the most may be searched for from a plurality of corresponding colors, and a color corresponding to this color may be used.
[0087]
[Other embodiments]
The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), but may be a device including one device (for example, a copying machine, a facsimile machine, etc.). May be applied.
Further, an object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and a computer (or CPU or MPU) of the system or apparatus to store the storage medium. Needless to say, this can also be achieved by reading out and executing the program code stored in the.
[0088]
In this case, the program code itself read from the storage medium realizes the function of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.
[0089]
As a storage medium for supplying the program code, for example, a floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM, or the like is used. I can do it. When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also an OS (Operating System) running on the computer based on the instruction of the program code. It goes without saying that a case where a part of the actual processing is performed and the function of the above-described embodiment is realized by the processing is also included.
Further, after the program code read from the storage medium is written into a memory provided on a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. It goes without saying that a CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.
[0090]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain color matching accuracy based on an objective criterion based on human visual characteristics. In addition, since color matching accuracy can be verified for each color conversion content based on objective judgment criteria based on human visual characteristics and the profile can be updated as appropriate, image processing that enables accurate color matching can be performed. An apparatus, a method thereof, and a medium thereof can be provided.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a functional configuration of an image processing apparatus according to a first embodiment of the present invention and showing peripheral devices thereof.
FIG. 2 is a flowchart of main processing of image processing performed by the image processing apparatus according to the first embodiment of the present invention.
FIG. 3 is a flowchart illustrating details of a process in which a color matching accuracy calculation unit 8 obtains color matching accuracy in step S204.
FIG. 4 is a diagram showing an a * b * plane in a CIELAB color space.
FIG. 5 is a diagram illustrating a configuration example of a table for each color conversion method.
FIG. 6 is a flowchart of a process in which the color matching accuracy determination unit 9 determines whether color matching accuracy is good or bad using the CRIn in step S205.
FIG. 7 is a flowchart illustrating the details of a process in which the profile creation / update unit updates the printer profile to the latest one in step S208.
FIG. 8 is a diagram showing a configuration example of a GUI displayed on the image display device 2.
FIG. 9 is a diagram illustrating a display example of a GUI for displaying matching accuracy, that is, CRIn, for each color of each patch displayed on the image display device 2.
FIG. 10 is a block diagram showing a functional configuration of an image processing apparatus according to a second embodiment of the present invention, and showing a configuration with peripheral devices thereof.
FIG. 11 is a flowchart of main processing of image processing performed by the image processing apparatus according to the second embodiment of the present invention.
FIG. 12 is a block diagram illustrating a functional configuration of a server-side image processing apparatus and a client-side image processing apparatus (hereinafter, an image processing server) according to a third embodiment of the present invention.
FIG. 13 is a flowchart of main processing performed by an image processing apparatus and an image processing server according to a third embodiment of the present invention.

Claims (22)

Data of a first color group including at least one or more colors and each color obtained by outputting each color of the first color group by an image output device, wherein each color is the first color group Storage holding means for storing and holding in association with each color of the second color group data constituted by each color having a predetermined relationship,
Data indicating a color group obtained by outputting the input color group by the image output device is input from the outside, and the data and the correspondence corresponding to the input color group stored and held in the storage unit are stored. Calculating a lightness error, a saturation error, and a hue error using the data of the color group; and calculating means for obtaining a color reproduction index of color matching using these errors. Image processing device. The image processing apparatus according to claim 1, wherein the storage unit stores and holds the data of the first color group and the data of the second color group for each color conversion method. The calculation means is based on a difference in brightness using data indicating a color group obtained by outputting the input color group by the image output device and data of a corresponding color group corresponding to the input color group. Value, a value based on the difference in saturation, a value based on the difference in hue, a value of the square root of the sum of squares of each value is obtained for each color, and the value of the square root obtained for each color is further obtained. The image processing apparatus according to claim 1, wherein an average value is obtained as a reproduction index of the color matching. Furthermore,
The image output device, a profile storage holding unit that stores and holds a profile of each device including an image display device,
Based on the average value, a notification unit that determines whether to update the profile of any one of the devices stored and held in the profile storage unit and notifies the determination result is provided. The image processing apparatus according to claim 1, wherein: 5. The image processing apparatus according to claim 4, wherein when the average value is larger than the predetermined threshold value, the notification unit notifies that a profile of one of the devices is updated. 6. apparatus. The image processing apparatus according to claim 4, wherein the notifying unit further notifies the value of the square root for each color. The image processing apparatus according to claim 1, further comprising an updating unit configured to update any one of the profiles of each of the devices. The image processing apparatus according to claim 7, further comprising a transmission unit configured to transmit the profile updated by the updating unit to an external device. Data of a first color group including at least one or more colors and each color obtained by outputting each color of the first color group by an image output device, wherein each color is the first color group Is stored in a memory in association with each color of the second color group data constituted by each color having a predetermined relationship.
Data indicating a color group obtained by outputting the input input color group by the image output device is externally input, and the data and a corresponding color group corresponding to the input color group stored and held in the memory An image processing method comprising: determining a lightness error, a saturation error, and a hue error using the data of (1) and (2), and further calculating a color reproduction index of color matching by using these errors. An image processing apparatus having image processing means for converting an input image signal into an output image signal,
The image processing unit includes a plurality of color conversion units, an accuracy calculation unit that calculates the accuracy of the color conversion,
An image processing apparatus comprising: an accuracy determination unit configured to determine a magnitude of a precision result calculated by the precision calculation unit and a preset threshold value. The image processing apparatus according to claim 10, further comprising: a color adjustment setting unit configured to set a color adjustment based on a determination result of the accuracy determination unit. The image processing apparatus according to claim 11, wherein the color adjustment setting unit includes a device characteristic information updating unit that updates device characteristic information of the image device. The device characteristic information updating unit uses the changed device characteristic information to calculate an accuracy of the color conversion, and a magnitude of the accuracy result calculated by the accuracy calculating unit and a preset threshold value. The image processing apparatus according to claim 12, further comprising: an accuracy determining unit configured to determine the image quality. The image processing apparatus according to claim 10, wherein the accuracy calculation unit is a unit that performs each of the plurality of color conversions. The accuracy calculating means may be a means for calculating using a corresponding color in the output image signal corresponding to the input image signal set in advance, a permissible value thereof, and the color-converted output image signal. The image processing apparatus according to claim 10, wherein: The accuracy calculation unit is a unit that calculates a difference based on a visual characteristic between a corresponding color in the output image signal corresponding to the preset input image signal and the color-converted output image signal. The image processing apparatus according to claim 15, wherein: 16. The image processing device according to claim 15, wherein a value is set for each corresponding color in the output image signal as the allowable value used by the accuracy calculation unit. 16. The image processing apparatus according to claim 15, wherein the allowable value used in the accuracy calculation unit is a value that is set in advance for each hue, saturation, and lightness and reflects a visual characteristic. 16. The image processing apparatus according to claim 15, wherein the corresponding color or the allowable value used in the accuracy calculation unit is set for each of the plurality of color conversions. The plurality of color conversion means is means for converting the input image signal into the corresponding output image signal so as to visually faithfully reproduce an image displayed on a monitor, and is more visually compared with the color conversion means. Means for converting the output image signal corresponding to a preferred color into at least one of the means for converting the input image signal into the output image signal so as to use the color gamut of the output device as vivid as possible The image processing apparatus according to claim 10, wherein: An image processing method having an image processing step of converting an input image signal into an output image signal,
The image processing step includes a plurality of color conversion steps, an accuracy calculation step of calculating the accuracy of the color conversion,
An image processing method, comprising: an accuracy determination step of determining the magnitude of an accuracy result calculated in the accuracy calculation step and a preset threshold value. In image processing, which is a recording medium for recording an image processing program and has an image processing function of converting an input image signal into an output image signal,
The image processing function includes a plurality of color conversion functions, an accuracy calculation function for calculating the accuracy of the color conversion, and an accuracy determination for determining the magnitude of an accuracy result calculated by the accuracy calculation function and a preset threshold value. A recording medium for recording a program for realizing a function.

Images