JP2003006629A - System for preparing color characteristic profile of monitor screen for image output and display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a profile expressing the color characteristics (RGB value and Lab value or the like) of a monitor screen for output and display of an unknown profile readily in a short time without requiring and expensive colorimeter. SOLUTION: This system is provided with a step for inputting color chart electronic image data to the computer of a monitor M of the unknown profile and reading the data, step for outputting and displaying a chart image on the monitor M, step for photographing and recording the chart image outputted and displayed on the monitor M by an electronic camera C of a known profile, step for inputting photographed electronic image data to the computer of another monitor MO and reading the data, step for outputting and displaying a chart photographed image PGS on the screen of the monitor MO, and step for outputting and recording the color component value of the chart photographed image PGS by using a program for color component value output and display processing packaged in this monitor MO and on the basis of the known color characteristic profile of the camera C, the color characteristic profile of the monitor M of color value-color component value, with which the color component value and the color value are made correspondent, is prepared.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to color transfer between various devices such as a monitor for image output display connected to a computer such as a digital camera, a video camera, a desktop personal computer or a notebook personal computer, a scanner or a printer. That is, the present invention relates to a system for creating a device color characteristic profile for realizing color management, and particularly to a monitor color characteristic profile creating system.

[0002]

2. Description of the Related Art As a conventional method for creating a monitor profile showing the color characteristics of a monitor screen for displaying a color image of a personal computer, a color image displayed on the monitor screen is directly measured with a colorimeter. Was there.

As described above, the method of measuring the color characteristics of the monitor screen whose profile is unknown by using the colorimeter to create the monitor profile is good in accuracy, but the colorimeter itself is expensive. Therefore, it lacks versatility,
It was difficult for anyone to easily create a monitor profile.

When a color image displayed on a monitor screen is measured by a colorimeter, a color image based on a color chart, for example, is used.
A plurality of block-shaped color patches having different color values (XYZ values, Lab values) are regularly arranged, and a plurality of color patches are sequentially measured and recorded using a colorimeter. It was necessary, and it took a considerable amount of time to measure colors per monitor.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a color characteristic of an output display monitor screen whose device profile of one or a plurality of devices is unknown in a short time easily without requiring an expensive colorimeter. The purpose is to create a profile representing (RGB value or Lab value), and the device profile is output and displayed on the monitor screen based on the color characteristics of the color image on the monitor screen taken by a known digital camera or video camera. It is to realize the creation of a color characteristic profile in color display of an image at low cost.

[0006]

The invention according to claim 1 of the present invention is, as shown in FIGS. 1, 2 and 3, (1) color values (XYZ values having different color characteristics such as hue and brightness). Or Lab
A color chart P in which a plurality of color patches p of known values are divided into blocks and arranged and displayed (see FIG. 1A).
Recording medium Pd on which electronic image data of
Computer 1 for connecting the color chart electronic image data from the reference image) to a computer image output display color monitor M (see FIG. 1B) whose color characteristic profile is unknown.
And (2) a color chart image PG is displayed on the screen of the monitor M (see FIG. 1B) based on the read color chart electronic image data Pd. Color chart image output display stage,
(3) The color chart image PG output and displayed on the screen of the monitor M is photographed by a digital camera or a video camera C whose color characteristic profile is known, and the photographed data is recorded as color chart photographed electronic image data PdS ( A computer for connecting the color chart photographing / recording stage shown in FIG. 1B) and (4) the color chart photographing electronic image data PdS photographed and recorded to a computer image output display color monitor MO different from the monitor M. 11, a color chart photographing electronic image data reading step using an image processing program, and (5)
The color chart photographed electronic image data Pd read in
A color chart photographed image output display stage for outputting and displaying the color chart photographed image PGS on the screen (see FIG. 1B) of the monitor MO based on S, and (6) the color outputted and displayed on the screen of the monitor MO. Each color patch photographed image pgS in the chart photographed image PGS
The color component values (R, G, B values: 0 to 255 for each) are output as the color component values of the monitor output image mounted on the monitor MO (R, G, B values). A color component value output display step of outputting and recording using an output display processing program, and (7) the digital camera or video camera C
Corresponding to the output display color component values (R, G, B values) of each color patch photographed image pgS, which is output and displayed on the monitor MO 1 based on the known color characteristic profile PFC (see FIG. 2). Color value (XYZ value or L
ab value), and a correspondence table TM (see FIG. 3) of color value-color component value in which the output display color component value and the color value are associated with each other.
And a monitor color characteristic profile creating step of creating a color characteristic profile of the monitor M whose color characteristic profile is unknown.

The invention according to claim 2 of the present invention is the color characteristic profile creating system for a monitor according to claim 1, wherein, as shown in FIGS. 3 and 4, after the step of creating the color characteristic profile of the monitor. In (1), the known color value (XYZ value or Lab value) of each color patch p in the created color value-color component value correspondence table TM (see FIG. 3) and the corresponding color Output display color component values (R, G, B values) for each patch photographed image pgS
A color value that may exist between each color value based on
Interpolation color value-interpolation color component value calculation step, which is obtained by calculating, by interpolation calculation, color component values that may exist between the output display color component values corresponding to the color values, and (2) interpolation calculation The interpolated color value-interpolated color component value obtained by the above is added between each color value and the output display color component value of the color value-color component value correspondence table TM (see FIG. 3). A color characteristic profile PFM of the monitor M whose color characteristic profile consisting of a value-color component value correspondence table ATM is unknown.
(Refer to FIG. 4) A monitor color characteristic profile creating step, which comprises:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a monitor color characteristic profile creating system of the present invention will be described in detail below.

FIG. 1A is a front view of a color chart for creating a color characteristic profile. In the color chart P, a plurality of color patches p having different color characteristics such as hue and brightness are divided into blocks. The color patches p are displayed in an array, and each color patch p has a color value [XYZ value (x +
y + z = 1)], or Lab value [L axis; brightness, a axis;
Red-based hue (+ a) to Cyan-based hue (-a), b
Axis: Yellow hue (+ b) to Blue hue (-
b)] is known.

1 (b) to 1 (e) are system block diagrams for creating a color characteristic profile of a monitor, and M is for displaying a computer image output connected to the computer 1 such as a personal computer whose color characteristic profile is unknown. A color monitor (output screen), C is a digital camera or digital video camera for photographing whose color characteristic profile is known, and D
Is a recording medium for recording electronic image data photographed by the camera, and MO is another color monitor (output screen) for computer image output display connected to the computer 11 such as a personal computer.

The color monitor MO may have a known or unknown color characteristic profile, and the color component values (R, G, B values) of the monitor output image are sent to the computer 11 connected thereto. The program software for color component value output display processing for output display is installed. The color component values (R, G, B values) are the R (red) color, G (green) color, and B (blue) color pixels (pixels) of the image output and displayed on the monitor output screen. The color display output value of) is represented by 8 bits, and (28
) = 256 gradations (0 to 255).

In the system of the present invention, the color chart P is recorded on the recording medium (CD-RO) as shown in FIG.
M, flexible disk, computer memory, etc.)
The electronic image data Pd of the color chart P recorded as the electronic image data is used.

A system according to claim 1 of the present invention is shown in FIG.
The system block diagram of (a) to (e) and the system flowchart of FIG. 2 will be described in detail below.

<S1> First, the color image of the color chart P shown in FIG. 1A is converted into electronic image data as shown in FIG.
For the computer 1 connected to the computer image output display color monitor M having an unknown color characteristic profile from the recording medium on which the color chart electronic image data Pd shown in FIG.
d is input and read using an image processing program.

<S2> Next, based on the read color chart electronic image data Pd, the color chart image PG
Is displayed on the screen of the monitor M whose color characteristic profile is unknown.

<S3> Next, the color chart image PG output and displayed on the screen of the monitor M is shown in FIG.
Photographed by a digital camera or a video camera C whose color characteristic profile shown in FIG.

<S4> The photographed digital image data is used as color chart photographed electronic image data PdS in FIG.
The data is once recorded in an appropriate recording medium D (CD-ROM, flexible disk, computer memory, etc.) shown in (d).

<S5> Subsequently, the color chart photographed electronic image data PdS recorded on the recording medium D is displayed on another computer image output display color monitor MO shown in FIG. It is input and read into the computer 11 to be connected using an image processing program.

<S6> The color chart photographed image PGS is output and displayed on the screen of the monitor MO based on the read color chart photographed electronic image data PdS.

<S7> Next, the color component values (R, R) for each color patch photographed image pgS in the color chart photographed image PGS output and displayed on the screen of the monitor MO.
G and B values: 0 to 255 for each color component value (R, R of the monitor output image mounted on the computer 11 of the monitor MO).
G and B values) are output using a color component value output display processing program for output display. Then, each color patch photographed image pgS (for example, patch numbers 1 to 228)
Each time, the output color component values (R, G, B values) are recorded manually or in the memory of the computer 11 or in its output means (printer or the like).

<S8> Subsequently, the display color component values (R, G, B values) for each color patch photographed image pgS output and displayed on the monitor MO are recorded (pairing).
The color value (XYZ value or Lab value) to be obtained is obtained based on the known color characteristic profile PFC (color characteristic table) of the digital camera or the video camera C shown in FIG.

<S9> Next, the display color component values (R, G, B values) of each color patch photographed image pgS (for example, patch numbers 1 to 228) and the corresponding color values (XYZ values). Or Lab value),
As shown in FIG. 5, a color value-color component value correspondence table TM is created, and this correspondence table TM is used as the color characteristic profile PFM of the monitor M whose color characteristic profile is unknown.

Next, the invention according to claim 2 of the present invention will be described in detail below with reference to the system flow chart of FIG. 3 and FIGS.

The system according to claim 2 is characterized by the system after the step <S9> of creating the correspondence table TM as the color characteristic profile PFM of the monitor M whose color characteristic profile is unknown in the system. Is.

<S10> Color value created as shown in FIG.
Known color values (X) for each color patch p (patch numbers 1 to 228) in the color component value correspondence table TM.
YZ value or Lab value) and the output display color component values (R, G, B values) corresponding to the corresponding (pairing) color patch photographed image pgS, which may exist between the respective color values. A color value and a color component value that can exist between the output display color component values corresponding to the color value are calculated by interpolation calculation (or a graph of an interpolation curve), and the interpolation color value-the interpolation color Calculate the component values.

<S11> Next, the interpolation color value-interpolation color component value obtained by the interpolation calculation is added between each color value and the output display color component value in the color value-color component value correspondence table TM. Are recorded, and the patch numbers of the color patches p (for example, 228 patch patterns; patch numbers 1 to 228) are interpolated and subdivided into appropriate numbers, and the interpolated color values (XYZ Value or Lab value) -color component value (R, G, B value) corresponding table ATM color characteristic profile PF of the unknown color characteristic profile PF of the monitor M
Create M.

As shown in FIG. 6, the color characteristic profile PFM of the monitor M consisting of the interpolated correspondence table ATM is obtained by further subdividing 228 color patches p from patch numbers 1 to 228 into color patches. The virtual number N of p is 32768 of patch numbers 1 to 32768.
It is virtually divided into individual pieces. This is the number N = 323 = 32768 by the combination of three colors when the color component values of R (red) color, G (green) color, and B (blue) color are set to 32 gradations, respectively. is there.
The virtual number N can be set appropriately as needed.

Further, as shown in FIG. 6, header information or the like may be displayed above the color characteristic profile PFM of the monitor M.

[0029]

The system of the present invention is a color chart photographed image obtained by photographing a color chart image output and displayed on a monitor whose profile is unknown with an electronic camera (digital camera, video camera, etc.) whose color characteristic profile is known. Based on the data (digital data), a color chart captured image is output and displayed on the output screen of another monitor, and the color component values (R, G) of the monitor output image mounted on the computer connected to the monitor that has output and displayed. , B values) are output and displayed, and the color component values (R, G, B values) of the output color chart photographed image are output and displayed for confirmation. By recording and associating (pairing) with the color values of the known color characteristic profile of the electronic camera, the color characteristics of the monitor whose profile is unknown are recorded. Can create a profile, without the need for conventional such expensive optical colorimeter, with a small effort, at low cost, there is an effect that it is possible to create a color characteristic profile of the monitor.

[Brief description of drawings]

FIG. 1A is a front view of a color chart image recorded on a recording medium on which color chart electronic image data used in the system of the present invention is recorded, and FIGS.
Is a system block diagram for explaining the system of the present invention.

FIG. 2 is a system flowchart illustrating a system of the present invention.

FIG. 3 is a system flowchart illustrating a system of the present invention.

FIG. 4 is a known color characteristic profile of an electronic camera used in the system of the present invention.

FIG. 5 is a color characteristic profile of a monitor created by the system of the present invention.

FIG. 6 is an interpolated color characteristic profile of a monitor created by the system of the present invention.

[Explanation of symbols]

P ... Color chart p ... Color patch Pd ... Color chart electronic image data PG ... Color chart image pg ... Color patch image M ... Profile unknown monitor PdS ... Color chart photographed image data C ... Electronic camera D ... Color chart photographed image Data recording medium MO ... Monitor PGS on which a program for color component value output display processing is installed ... Color chart shot image pgS ... Color patch shot image PFC ... Camera color characteristic profile TM ... Color value-color component value correspondence table ATM ... Interpolated Color value-color component value correspondence table PFM ... Monitor color characteristic profile 1, 11 ... Computer

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 9/64 H04N 1/46 ZF term (reference) 5B057 AA20 CA01 CB01 CE17 CE20 CH07 5C066 AA01 BA20 CA06 EB01 EC01 EE04 GA01 GA32 HA02 JA01 KE04 5C077 LL11 MP08 PP32 PP36 PQ23 SS07 TT10 5C079 HA15 HB01 HB08 HB11 LB01 MA04 MA17 NA03 PA05 5C082 AA19 AA27 BA34 CA12 CB06 DA51 DA87 MM04 MM09

Claims (2)

[Claims] 1. (See FIGS. 1, 2, and 3) (1) Color values (XYZ) having different color characteristics such as hue and brightness.
A color chart P (FIG. 1) in which a plurality of color patches p whose known values or Lab values) are known are divided into blocks and arranged and displayed.
Recording medium Pd recording electronic image data (see (a))
The color chart electronic image data from (see FIG. 1B) is connected to the computer image output display color monitor M (see FIG. 1B) whose color characteristic profile is unknown by using the image processing program in the computer 1. The step of reading the color chart electronic image data to be read, and (2) the color chart image PG based on the read color chart electronic image data Pd is displayed on the screen of the monitor M (FIG. 1).
(B)) A color chart image output display stage for output and display on the screen, and (3) digital camera or video camera C with a known color characteristic profile for the color chart image PG output and displayed on the screen of the monitor M. Photographed at, and the photographed data is the color chart photographed electronic image data P
A color chart photographing / recording step of recording as dS (see FIG. 1B), and (4) the color chart photographing electronic image data PdS photographed and recorded, which is different from the monitor M, for displaying a computer image output color monitor MO. A color chart photographed electronic image data reading step using an image processing program to a computer 11 connected to the color chart photographed electronic image data PdS based on the read color chart photographed electronic image data PdS.
A color chart photographed image output display step of outputting and displaying GS on the screen of the monitor MO (see FIG. 1B), and (6) each color in the color chart photographed image PGS output and displayed on the screen of the monitor MO. Color component values (R, G, B values: 0 to 0 for each patch photographed image pgS)
255) for outputting and displaying the color component values of the monitor output image mounted on the monitor MO 1 (R, G, B).
(Value) Output and recording of color component values using an output display processing program, and (7) Known color characteristic profile PFC of the digital camera or video camera C.
(See FIG. 2), the color value (XYZ value or XYZ value corresponding to the output display color component value (R, G, B value) for each color patch photographed image pgS output and displayed on the monitor MO 1 is recorded. Lab value), and a correspondence table T of color value-color component value in which the output display color component value and the color value are associated with each other.
A monitor color characteristic profile creating system comprising: a monitor color characteristic profile creating step of creating a color characteristic profile of the monitor M having an unknown color characteristic profile M (see FIG. 3). 2. (Refer to FIGS. 3 and 4) After the step of creating a color characteristic profile of the monitor,
(1) Correspondence table TM of the created color value-color component value
(See FIG. 3), known color values (XYZ values or Lab values) for each color patch p and corresponding output display color component values (R, G, B values) for each color patch photographed image pgS. Based on, the color value that can exist between the color values and the color component value that can exist between the output display color component values corresponding to the color value are calculated by interpolation calculation. Interpolation color value-interpolation color component value calculation step, and (2) the interpolation color value-interpolation color component value obtained by the interpolation calculation, in each of the color value-color component value correspondence table TM (see FIG. 3). In addition to the color value and the output display color component value, a color characteristic profile PFM (see FIG. 4) of the monitor M whose color characteristic profile is unknown, which is composed of the interpolated color value-color component value correspondence table ATM, is created. Monitor color characteristic profile creation stage The color characteristic profile creating system for a monitor according to claim 1, wherein the system comprises: