JP2002209117A - Image processing system, its image processing method and picture processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing system, its image processing method and an image processor for correcting the influence of reflected light on the displaying surface of a display device when printing out a display color on the display device faithfully by a printer. SOLUTION: A user sets a monitor black level under observed environment by a black level setting part 107. A black level correction part 106 estimates a color to be displayed on a monitor under the observed environment, and a color mapping part 102 gives color processing so that the same color hue is reproduced at the monitor and at the printer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image processing system, an image processing method, and an image processing apparatus for realizing similar color reproduction in a connected display device and printing device.

[0002]

2. Description of the Related Art In general, in order to faithfully print a color displayed on a color monitor by a computer with a color printer, a color processing apparatus having a configuration shown in FIG. 8 is used, for example. In the figure, the monitor simulation unit 81 refers to the monitor profile 84 and refers to the signal value [R
m, Gm, Bm] to estimate the CIE tristimulus values (colorimetric values) [Xm, Ym, Zm] of the color displayed on the monitor. The color mapping unit 82 outputs a CIELAB (colorimetric value) [Lp of a color suitable for the device user's intention from among colors reproducible by the printer as a print output color of the CIE tristimulus values [Xm, Ym, Zm]. *, ap *, bp *]. The printer simulation unit 83 refers to the printer profile 85 describing the color reproduction characteristics of the printer,
A printer signal value [Rp, Gp, Bp] for printing the above CIELAB [Lp *, ap *, bp *] is estimated.

[0003] By such a series of processes, a printer signal value [Rp, Gp, Bp] corresponding to the monitor signal value [Rm, Gm, Bm] is obtained, and a color matching the color on the monitor can be printed. it can.

[0004] Here, there is a problem that a sufficient match cannot be obtained depending on the lighting conditions because the color appearance is actually changed by the observation illumination. In order to solve this problem, in recent years, techniques for correcting the influence of observation illumination have been proposed. For example, a method has been proposed in which tristimulus values of a reflection original under typical illumination are mutually converted by a linear function, and generally good matching is possible even under different illuminations.

[0005]

The above-mentioned prior art is intended to correct the influence of illumination on a reflection original, and the monitor is not affected by the observation light source. I consider it to be.

However, actually, the signal values [Rm, Gm, Bm]
And the CIE tristimulus values (colorimetric values) [Xm, Ym, Zm] of the colors displayed on the monitor in response to this, due to the effect of the reflection on the monitor surface (monitor surface reflection), It changes according to the observation illumination. Therefore, under a condition other than a predetermined condition (generally under darkness), printing with a color that exactly matches the color appearance on the monitor cannot be performed.

[0007] In particular, the reflection of illumination light on the monitor tube surface is
Significantly affects the appearance of low brightness and high saturation colors. In FIG.
The relationship between monitor light emission luminance and lightness at low lightness is schematically shown. According to the figure, it can be seen that a slight change in luminance due to reflected light on the tube surface greatly affects lightness having a high correlation with color appearance.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made in consideration of the above-described problems, and has been made in consideration of the above-described circumstances. It is an object to provide a processing system, an image processing method thereof, and an image processing device.

[0009]

In order to achieve the above object, the present invention has the following arrangement.

That is, an image processing system in which a display device and a printing device are connected to an image processing device, wherein the image processing device has environment setting means for setting parameters related to the display device in an observation environment; Display color estimating means for estimating a color to be displayed on the display device under the viewing environment based on the parameters, and the display device and the printing device for the display color estimated by the display color estimating means. And color processing means for performing color processing so as to reproduce similar colors.

For example, the observation environment is an observation illumination environment.

[0012] For example, the parameter indicates an influence of reflection of observation illumination on a display surface of the display device.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below in detail with reference to the drawings.

<First Embodiment> FIG. 1 is a diagram showing a system configuration in which this embodiment is implemented. A computer 201 stores image data, inputs parameters, performs various calculations, and controls the system. A monitor used for displaying image data and a user interface held in the computer 201; and 203, a color printer (hereinafter, printer) for printing image data on a recording medium.

FIG. 2 shows the inside of the computer 201.
FIG. 2 is a block diagram illustrating a configuration for realizing color processing according to the embodiment. In the figure, the monitor simulation unit 81 refers to the monitor profile 104 describing the color reproduction characteristics of the monitor 202, and obtains the signal value [Rm, G
m, Bm], the color CI displayed on the monitor 202 in the dark.
E Estimate tristimulus values (colorimetric values) [Xm, Ym, Zm].

The black level setting unit 107 outputs a monitor signal value [Rm, G
The CIE tristimulus value [X0, Y0, Z0] (black level) at [m, Bm] = [0, 0, 0] is received from the user via an operation unit (not shown).
The details of the method of setting the black level will be described later. The black level correction unit 106 uses the black level [X0, Y0, Z0] and the CIE tristimulus values [Xm, Ym, Zm] under the dark corresponding to the monitor display signal [Rm, Gm, Bm], The CIE tristimulus values [Xe, Ye, Ze] of the color on the monitor under observation illumination are estimated.

The color mapping unit 102 outputs the CIE tristimulus value [Xe, Ye, Ze] as a print output color from among colors reproducible by the printer 203 and CIELAB of a color suitable for the intention of the device user.
(Colorimetric value) [Lp *, ap *, bp *] is obtained. As a detailed configuration, the color mapping unit 102 has a white point conversion unit 1021 that compensates for a difference between a white point (for example, D65) displayed on the monitor 202 and a white point (for example, D50) at the time of printing by the printer 203.
And XYZ / L * a * b to calculate CIELAB using white on monitor 202
* Includes a conversion unit 1022 and a color gamut compression unit 1023 that compensates for the difference in color reproduction range between the monitor 202 and the printer 203.

The printer simulation unit 103 includes a printer profile 1 describing the color reproduction characteristics of the printer 203.
Referring to 05, a printer signal value [Rp, Gp, Bp] for printing the above CIELAB [Lp *, ap *, bp *] is estimated.

With the above configuration, the color signal [Rm, Gm, Bm] of each pixel constituting the color image displayed on the monitor 202 is
The monitor simulation unit 101 converts the CIE tristimulus values [Xm, Ym, Zm] under darkness, and then the black level correction unit 106 converts them into CIE tristimulus values [Xe, Ye, Ze] under observation illumination. . The present embodiment is characterized in that the CIE tristimulus values [Xe, Ye, Ze] under observation illumination are used as inputs to the color mapping unit 102.

The CIE tristimulus values [Xe, Ye, Ze] are matched by the color mapping unit 102 to C
The data is converted into IELAB [Lp *, ap *, bp *], and then converted into a printer signal value [Rp, Gp, Bp] by the printer simulation unit 103.

The monitor signal value [Rm,
Gm, Bm], and a printer signal value [Rp, Gp, Bp] corresponding to the color on the monitor 202 can be printed by the printer 203.

Here, the details of the processing in the black level setting section 107 will be described with reference to the flowchart of FIG.

First, in the observation environment, a monitor signal value [Rm, Gm, Bm] = [0, 0, 0] is displayed on the monitor 202 (S301).
The CIE tristimulus value is measured with a radiance meter or the like (S302). The CIE tristimulus values [X0, Y0, Z0] obtained as the measurement result are the tristimulus values of the tube surface reflection on the monitor 202. Next, the CIE tristimulus values [X0, Y0, Z0] obtained in step S302 are set as a black level using a black level setting user interface (UI) (S303).

FIG. 4 shows a screen example of the black level setting UI.
The UI will be described. In the screen shown in FIG.
An X setting unit for CIE tristimulus values, 42 is the same Y setting unit, 43 is the same Z setting unit, 44 is a setting button, and 45 is a cancel button. On this screen, the cursor 46 can be arbitrarily moved by the user. Input the black levels [X0, Y0, Z0].

When the setting button 44 is pressed, the input values of X0, Y0, and Z0 are set, and the set values are used by the black level correction unit 106 thereafter. on the other hand,
When the cancel button 45 is pressed, the input is ignored, and the previous setting value is used in the black level correction unit 106. The initial setting value of the black level is, for example, [X0, Y0, Z0]
= [0,0,0], and if the set value is used as it is, printing is performed with a color that matches the monitor under the darkness.

The black level correction unit 106 receives the CIE tristimulus values [Xm, Ym, Zm] in the dark corresponding to the monitor display signal [Rm, Gm, Bm] from the monitor simulation unit 101, and sets the black level setting unit. Using the black level [X0, Y0, Z0] under observation illumination set in 107, based on the following equation (1), the CIE tristimulus value [X
e, Ye, Ze].

Xe = Xm + X0 Ye = Ym + Y0 (1) Ze = Zm + Z0 [Xe, Ye, Ze] is output to the color mapping unit 102.

As described above, according to the present embodiment,
A user inputs a black level under observation illumination, that is, a tristimulus value of a monitor tube surface reflection, and estimates a monitor display color (CIE tristimulus value [Xe, Ye, Ze]) under observation illumination based on the tristimulus value. By using as input for color mapping,
It is possible to print a color that matches a monitor under observation illumination.

The color mapping is not limited to the one shown in FIG. 2. If the printer profile corresponds to three stimulus values, the processing of the color mapping unit and the print simulation unit may be performed collectively. It does not matter.

<Second Embodiment> Hereinafter, a second embodiment according to the present invention will be described.
An embodiment will be described.

FIG. 5 is a block diagram showing a configuration for realizing the second embodiment, and corresponds to FIG. 2 in the first embodiment described above. And the black level correction unit 506 refers to the monitor profile 504.

The monitor profile 504 shown in FIG. 5 holds, in addition to the monitor color reproduction characteristics under darkness, the tristimulus value of monitor tube surface reflection as a black level under general illumination. Here, as general lighting, for example, 500 lx, 100 l of high color rendering day white fluorescent lamp (5000K) and white fluorescent lamp (4200K)
0lx, 1500lx, 2000lx are assumed.

The illumination selection unit 507 includes a monitor profile 504
Is presented to the user by the illumination selection UI, and one condition most suitable for the actual observation environment is selected. The lighting selection UI is implemented as, for example, a pull-down list or a radio button.

The black level correction unit 506 converts the black level under the illumination selected by the illumination selection unit 507 into a monitor profile.
504, and using the black level [X0, Y0, Z0] and the CIE tristimulus values [Xm, Ym, Zm] in the dark corresponding to the monitor display signal [Rm, Gm, Bm] under observation illumination. Estimate the CIE tristimulus values [Xe, Ye, Ze] of the colors on the monitor at. This estimate is
This is performed based on equation (1) shown in the first embodiment.

The monitor simulation unit 501, the color mapping unit 502, and the printer simulation unit 50
3. The printer profile 505 performs the same processing as the configuration shown in FIG. 2 in the first embodiment described above.

As described above, according to the second embodiment, the tristimulus values of the monitor tube reflection under typical illumination are stored in the monitor profile, and from this illumination list, the conditions most suitable for the observation environment are stored. By allowing the user to select, it is possible to estimate the monitor display color under observation illumination and print a color that matches this.

Third Embodiment Hereinafter, a third embodiment according to the present invention will be described.
An embodiment will be described.

The configuration for realizing the third embodiment is the same as that shown in FIG. 2 shown in the first embodiment, except that the black level setting unit 107 is provided with a plurality of patches for confirming the black level. The image is test-printed by the printer 203, and the user selects a patch that matches the black level confirmation color displayed on the monitor 202 in the test print image, and sets the black level based on the result. .

Then, the black level correction unit 106 generates the CIE tristimulus under darkness corresponding to the black level [X0, Y0, Z0] set by the black level setting unit 107 and the monitor display signal [Rm, Gm, Bm]. Using the values [Xm, Ym, Zm], the CIE tristimulus values [Xe, Ye, Ze] of the color on the monitor under observation illumination are estimated. This estimate also
This is performed based on equation (1) shown in the first embodiment.

Hereinafter, a black level setting unit 107 according to the third embodiment will be described.
Will be described in detail.

First, in the black level confirmation image to be test-printed, a printer print color that matches a color on a monitor under general illumination is arranged in a patch shape with respect to one or more black level confirmation colors. Things. For example, 500l of high color rendering neutral white fluorescent lamp (5000K) and white fluorescent lamp (4200K)
Under each illumination of x, 1000 lx, 1500 lx, and 2000 lx, the printing color of the printer 203 corresponds to the case where the black level confirmation color [Rm, Gm, Bm] = [128, 0, 0] is displayed on the monitor 202. 9 is a patch image showing the following. That is, the printer 20 performs black level correction and color mapping based on the tristimulus values [X0, Y0, Z0] of the monitor tube surface reflection indicating the black level of the monitor 202 under a plurality of predetermined illuminations.
The patch image is output on a recording medium as a print result in 3.

FIG. 6 is a block diagram showing a detailed configuration of the black level setting unit 107 in the third embodiment. In the figure, reference numeral 601 denotes a confirmation image holding unit, 602 denotes a black level data holding unit, 603 denotes a data input UI unit, and 604 denotes a setting data holding unit.

The confirmation image holding unit 601 stores the above-described black level confirmation image for test printing. The black level data holding unit 602 stores a black level [X0, Y0, Z0] corresponding to each patch of the black level confirmation image, that is, under each illumination. The data input UI unit 603 displays the above-described black level confirmation color [Rm, Gm, Bm] on the monitor 202, and selects the monitor 20 from the patches of the printed black level confirmation image.
2. Let the user select the one that best matches the display color above. The setting data holding unit 604 stores the black level corresponding to the patch selected by the user in the data input UI unit 603 as the black level [X0, Y0, Z0] that most closely matches the current viewing environment.

FIG. 7 shows an example of a screen in the data input UI unit 603, and the UI will be described. In the figure, 701
Denotes a confirmation color display unit, 702 denotes a patch number setting unit, 703 denotes a confirmation image print button, 704 denotes a setting button, and 705 denotes a cancel button.

On this screen, the cursor 706 can be arbitrarily moved by the user. When the confirmation image print button 703 is pressed via the cursor 706 or an operation button (not shown), a black level confirmation image for test printing is displayed. Is a printer 20
Printed out in 3. The confirmation color display section 701 displays the black level confirmation color [Rm, Gm, Bm]. The user can select the black level confirmation color displayed on the confirmation color display section 701 from among the patches of the printed confirmation image. The patch of the color that best matches [Rm, Gm, Bm] is detected, and the patch number is set in the patch number setting unit 702.

The patch number setting section 702 is implemented as, for example, a pull-down list, and can select a batch number added to each patch of the printed black level confirmation image or “no black level correction”.

When the setting button 704 is pressed, a black level value [X0, Y0, Z0] corresponding to the set patch number is set in the setting data holding unit 604. Thereafter, the set value is set to the black level correction unit. Used in 106. On the other hand, if the cancel button 705 is pressed, the input is ignored, and the setting data holding unit 604 holds the previous setting value as it is. When “no black level correction” is selected in the patch number setting unit 702, the black level [X0, Y0, Z0] = [0, 0, 0]
Is set in the setting data holding unit 604, and by using this, printing is performed in a color matching the monitor under the darkness.

As described above, according to the third embodiment, a color patch corresponding to the monitor display color under typical illumination is test-printed by the printer, and the user can best match the observation illumination based on the printing result. By selecting the patch that is used, it is possible to estimate the monitor display color under observation illumination and print a color that matches this.

In the third embodiment, an example in which a black level confirmation image is test-printed has been described. For example, a printed matter of a black level confirmation image is prepared in advance, and a black level image displayed on a monitor is prepared based on the printed matter. The comparison with the level confirmation color may be performed.

Also, an example has been described in which a color matching the black level confirmation color displayed on the monitor is selected from a plurality of test-printed patches. It is also possible to configure so as to select a color that matches the level confirmation color.

[0051]

Another embodiment of the present invention is to accurately obtain a color displayed on a monitor by considering the influence of illumination, that is, reflection on a monitor tube surface, in color processing of monitor matching. Yes, and therefore does not depend on the configurations of the color mapping unit and the printer simulation unit in the above embodiments.

In each of the above embodiments, examples have been described in which the influence of observation illumination is corrected using the CIE tristimulus values at the black level [Rm, Gm, Bm] = [0, 0, 0]. , [0,0,0], or a value other than CIE tristimulus values, such as CIELAB, may be used.

Another 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,
Needless to say, the present invention is also achieved by a computer (or a CPU or an MPU) of the system or the apparatus reading and executing the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

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, RO
M or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) Do some of the actual processing,
It goes without saying that a case where 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 in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, The CPU provided in the function expansion board or function expansion unit performs part or all of the actual processing,
It goes without saying that a case where the function of the above-described embodiment is realized by the processing is also included.

[0058]

As described above, according to the present invention, it is possible to correct the influence of the reflected light on the display surface of the display device when the display color on the display device is faithfully printed out by the printing device. . Therefore, printing with the same color as the display color on the display device can be performed regardless of the lighting conditions.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an image processing system according to the present invention.

FIG. 2 is a block diagram showing a configuration for realizing color processing in first and third embodiments according to the present invention.

FIG. 3 is a flowchart illustrating processing in a black level setting unit according to the first embodiment.

FIG. 4 is a diagram illustrating a screen example of a black level input UI according to the first embodiment.

FIG. 5 is a block diagram showing a configuration for realizing color processing in a second embodiment.

FIG. 6 is a block diagram illustrating a detailed configuration of a black level setting unit according to a third embodiment.

FIG. 7 is a diagram illustrating a screen example of a data input UI according to a third embodiment.

FIG. 8 is a block diagram illustrating a configuration of a conventional color processing device that converts a monitor display color into a print color.

FIG. 9 is a diagram schematically illustrating a relationship between light emission luminance and brightness of a monitor.

[Explanation of symbols]

 201 Computer 202 Monitor 203 Color printer 41 X input section 42 Y input section 43 Z input section 44 Setting button 45 Cancel button 46 Cursor 701 Confirmation color display section 702 Patch number setting section 703 Confirmation image print button 704 Setting button 705 Cancel button 706 Cursor

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B057 AA11 BA23 BA25 CA01 CA08 CA12 CA16 CB01 CB08 CB12 CB16 CE17 CE18 CH11 CH18 DA16 DA17 5C077 LL12 LL19 MM27 MP08 PP31 PP32 PP36 PP37 PP66 PP74 PQ08 PQ12 PQ22 TT01 SS05 SS06 SS06 SS06 HB05 HB08 HB11 KA20 LA31 LB02 MA01 MA10 MA11 MA17 MA19 NA03 NA21 PA03 PA05

Claims (16)

[Claims] 1. An image processing system in which a display device and a printing device are connected to an image processing device, the image processing device comprising: environment setting means for setting parameters relating to the display device in an observation environment; Display color estimating means for estimating a color to be displayed on the display device under the observation environment based on the parameters, and the display device and the printing device for the display color estimated by the display color estimating means. And a color processing means for performing color processing such that a similar color is reproduced. 2. The image processing system according to claim 1, wherein the observation environment is an observation illumination environment. 3. The image processing system according to claim 2, wherein the parameter indicates an influence of reflection of observation illumination on a display surface of the display device. 4. The image processing system according to claim 3, wherein the parameter is set for each color component constituting a display color on the display device. 5. The image processing system according to claim 4, wherein the parameter is a colorimetric result of a reference color displayed on the display device in the observation environment. 6. The image processing system according to claim 5, wherein the reference color is black. 7. The image processing system according to claim 5, wherein the parameter is manually set by a user in the environment setting unit. 8. The display color estimating unit adds each color component value set as the parameter to each component of a color signal to be displayed on the display device,
The image processing system according to claim 4, wherein the display color is estimated. 9. The environment setting means, holding means for holding the parameters in advance for a plurality of observation environments, selection means for selecting any of the plurality of observation environments,
2. The image processing system according to claim 1, further comprising: setting parameters according to the observation environment selected by the selection unit. 10. The image processing system according to claim 9, wherein the holding unit describes a color reproduction characteristic of the display device, and is a profile referred to by the color processing unit. 11. The environment setting means includes: display means for displaying a predetermined reference color on the display means; and a plurality of color patches estimated as display colors under a plurality of observation environments based on the reference color. A printing unit that causes the printing unit to print and output; and a setting unit that sets a parameter based on a patch having a tint closest to a reference color displayed on the display unit among the patches of the printed plurality of colors. The image processing system according to claim 1, wherein: 12. An image processing apparatus connected to a display device and a printing device, comprising: environment setting means for setting parameters related to the display device in an observation environment; A display color estimating unit for estimating a color displayed on the display device, and a similar color tone is reproduced in the display device and the printing device for the display color estimated by the display color estimating unit. And a color processing means for performing color processing on the image. 13. A setting step of setting a black level of a display device under an observation environment, and a display color estimation step of estimating a color displayed on the display device under the observation environment based on the set black level. And a color processing step of performing color processing on the display color estimated by the display color estimating means so that the same color is reproduced in the display device and the printing device. Image processing method. 14. An image processing method used when an image displayed on a display device is output by another output device, wherein the input image data is converted into tristimulus values using a profile corresponding to the display device. And adding a tristimulus value indicating a black level in an observation environment when observing the displayed image to the tristimulus value, and adding a profile of an output device to the sum of the tristimulus values. An image processing method, comprising: performing a conversion process according to 15. A program executed in an image processing apparatus connected to a display device and a printing device, the program comprising: a code for an environment setting step for setting parameters relating to the display device in an observation environment; The display color estimating step of estimating a color to be displayed on the display device under the observation environment, and a display color estimated by the display color estimating means. A code for a color processing step of performing color processing so that a similar color is reproduced. 16. A recording medium on which the program according to claim 15 is recorded.