JP2000287093A - Image processing unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow a user to simply and accurately discriminate the need for updating of a conversion characteristic of an image processing unit, that is used to convert image data into image forming data. SOLUTION: A test chart 40 by which propriety of an updated conversion characteristic can visually be identified is generated (printed), when the image processing unit is started or the image processing unit receives a command from a user. This test chart 40 consists of a character pattern and a background pattern, the character pattern is printed in a medium tone color using black (K) ink, and the background pattern is printed in the same medium tone color as that of the character pattern by adjusting blending three ink colors in total C(cyan), M(magenta), and Y(yellow). As a result, when the conversion characteristic used by the image processing unit at printing is deviated from an optimum value, characters appear on the printed test chart 40, and the user can discriminate the propriety of the updated conversion characteristic at a glance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for forming an image on a predetermined recording medium such as recording paper by outputting image forming data to an image forming apparatus such as a printer.

[0002]

2. Description of the Related Art Conventionally, in an image processing apparatus of this type, when an image forming apparatus such as a printer forms a desired image, the image data is set in advance according to the image forming characteristics of the image forming apparatus. The conversion characteristic data is used to convert the data into image formation data (image formation data), which is output to the image forming apparatus.

Further, if the conversion characteristic data used for converting image data into image forming data is fixed,
Due to a change in image forming characteristics of the image forming apparatus due to a change in the use environment or the like, an image formed by the image forming apparatus may have a different color from an image to be formed.

Therefore, in the conventional image processing apparatus, a colorimetric test chart is formed on the image forming apparatus in order to make the conversion characteristic data correspond to the image forming characteristic of the image forming apparatus. It is also known that the gradation characteristic of the image is measured using a colorimeter and the conversion characteristic data can be updated based on the colorimetric data obtained by the measurement and the image data of the test chart (for example, And Japanese Patent Publication No. 2755300).

In order to make the conversion characteristic data always correspond to the image forming characteristic of the image forming apparatus, a program for setting (updating) the conversion characteristic data is provided immediately after the image processing apparatus is started. And forcing the user to set the conversion characteristic data by executing this program.

[0006]

However, when updating the conversion characteristic data, the user sets the recording medium on the colorimeter or operates the colorimeter to use the colorimeter to read the image. A test chart formed on a storage medium such as paper by the forming apparatus must be measured. For this reason, as described above, if the user is forced to perform the setting operation of the conversion characteristic data, the user is forced to perform a complicated operation, and the work efficiency is reduced. There is.

On the other hand, in an image processing apparatus that updates the conversion characteristic data in accordance with a command from the user, the user can perform setting work as needed, so that the burden on the user can be reduced. It is very difficult for the user to appropriately determine whether the setting operation should be performed, and as a result, the setting operation tends to be neglected. If this operation is neglected, a desired image cannot be formed on the storage medium, and as a result, the work efficiency of the user will be reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and allows a user to easily determine whether or not to update conversion characteristic data used by an image processing apparatus to convert image data into image forming data. It is another object of the present invention to enable accurate and accurate determination.

[0009]

Means for Solving the Problems, Embodiments of the Invention, and Effects of the Invention In order to achieve the above object, the image processing apparatus according to the first aspect of the present invention provides an image processing apparatus for transmitting image data to an external image forming apparatus. Conversion means for converting the image forming data into image forming data corresponding to the characteristic, conversion characteristic storing means for storing conversion characteristic data used by the converting means for converting the image data, and the image forming apparatus An image processing apparatus for forming a color image on an image forming apparatus capable of forming a color image on a recording medium using a plurality of image forming materials of different colors. Test data storage means for storing test data used to form a test chart used for visual evaluation in the image forming apparatus, according to an external command, Test data output means for converting the test data into image forming data based on the conversion characteristic data, and outputting the test data to the image forming apparatus. The image forming material or the image forming material is distributed by changing the distribution of the image forming material for each of the plurality of regions.

As described above, in the image processing apparatus of the present invention (claim 1), the test data output means allows the user to visually evaluate whether or not the conversion characteristic data needs to be updated by an external command. Is formed on the image forming apparatus. Further, this test chart is obtained by changing the image forming material or the distribution of each image forming material for each of a plurality of image forming areas on the recording medium on which the image forming apparatus forms images in a predetermined pattern. It is a color scheme.

Therefore, according to the image processing apparatus of the present invention, the user visually checks the color arrangement pattern of the test chart formed by the image forming apparatus to determine whether or not the conversion characteristic data needs to be updated. The setting work of the conversion characteristic data using the colorimeter can be performed only when necessary. In addition, in order to determine whether or not the conversion characteristic data needs to be updated, it is only necessary to input a command for forming a test chart in the image forming apparatus. There is no reduction in efficiency.

Here, the test chart for visually evaluating the user may be formed so as to determine the degree of color approximation of each region by visual evaluation. As described in 3, each region may be divided by a predetermined pattern in which a character or a symbol is made into a graphic. Further, by combining these, each region is divided by a predetermined pattern in which a character or a symbol is made into a graphic. It may be formed to determine the degree of color approximation.

[0013] In particular, when the user is to determine the degree of color approximation, the test data is stored in a single image forming area on the recording medium in a predetermined pattern. It is preferable that the image forming material or the distribution of each image forming material is changed for each of the areas divided into the image forming data to form the same halftone color.

That is, for example, an image forming apparatus such as a color printer is provided with four color inks of K (black) color ink, C (cyan) color ink, M (magenta) color ink, and Y (yellow) color ink. There is a material that forms a color image on a recording medium using an image forming material such as. Also, C, M, Y
It is widely known that, by mixing or overcoating on a recording medium, the same color as K or a color close to K can be formed. Then, the test chart is formed by a K color pattern formed by the K color ink and a mixed color pattern formed by the C, M, and Y inks, and furthermore, the test chart is arranged such that respective boundaries of the patterns are in contact with each other. And K,
When the used amount of any one of the C, M, and Y color inks changes, a difference (color difference) appears in the colors between the patterns. Such a color difference can be sufficiently confirmed by the user himself / herself. Further, in the case of the test chart including the K color pattern and the two color patterns of C, M, and Y as described above, if each of these patterns is set to the halftone color, the slight variation of the image forming apparatus can be prevented. , The color difference between the patterns becomes large.

For this reason, if the test data used to form the test chart for visual evaluation in the image forming apparatus is configured as described in claim 4, the user can perform the test after the formation. From the chart, the necessity of updating the conversion characteristic data can be very easily and reliably visually evaluated.

On the other hand, the formation of such a test chart in the image forming apparatus is performed not only by applying an external command as in claim 1, but also by the test data output means as in claim 5. The test data may be output from the output unit to the image forming apparatus even when the power of the apparatus is turned on.

With this configuration, the test chart can be formed at all times when the image processing apparatus is started up. Therefore, when a desired image is to be formed immediately after the image processing apparatus is started up, the image forming apparatus can be used. It is possible to prevent problems such as color abnormalities that occur when an image is formed in an unstable state.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a main block diagram of a personal computer 2 according to an embodiment to which the present invention is applied.

This personal computer (hereinafter referred to as PC)
The computer unit 4 which is the main body of the CPU 2 is a CPU 1
0, ROM 12, RAM 14, and HDD (hard disk drive) 16. The HDD 16
Is connected to the CP via the bus 18 and the interface 20.
U10, ROM 12, and RAM 14 are connected. The interface 18 is connected to the bus 18 of the computer unit 4.
2, a keyboard 30, a mouse 32, and a monitor 3
4, a printer 36 as an image forming apparatus, and a colorimeter 38
And are connected.

In accordance with an external command, the HDD 16
Any image data is converted into data for image formation (image formation data) based on preset conversion characteristic data, output to the printer 36, and the image to be printed on predetermined recording paper by the printer 36. Various programs to be executed by the CPU 10, such as a test chart forming process for causing the printer 36 to print a test chart for causing the user to evaluate the necessity of the formation process and the update of the conversion characteristic data, are stored. Also, the HDD 16 has
Conversion characteristic data and image data (test data) of the test chart necessary for the CPU 10 to execute the image forming process and the test chart forming process are also stored together with the corresponding programs.

In this embodiment, the HDD 16 functions as the conversion characteristic data storage unit and the test data storage unit according to the first aspect, and the CPU 10 executes the image forming processing program stored in the HDD 16. Thereby, the functions as the conversion unit and the output unit according to the first aspect are realized.

Here, the printer 36 has K (black ink), C
This is a known color printer capable of forming an image on a recording medium using four colors of inks (cyan), M (magenta), and Y (yellow). The test data stored in the HDD 16 is transmitted to the printer 36. This is for printing a test chart 40 set as shown in FIG.

That is, in this embodiment, the test chart 40
As shown in FIG. 2, a predetermined character pattern, for example, “Calibration” is set in advance, and the test data sends the character pattern to the printer 36 in a predetermined image forming area on the recording sheet ( (In the frame shown in FIG. 2). This test data is obtained by painting a character pattern using K ink so as to have a halftone color (K50%: gray), and a portion other than the character serving as the background of the character pattern (hereinafter referred to as a background pattern). Is set to be painted in the same color as the character pattern using the respective inks of C, M, and Y. That is, by outputting image forming data obtained by converting the test data based on the image conversion data to the printer 36, the test chart 4 is printed on a predetermined recording sheet.
When 0 is printed and the test chart 40 is printed normally, the character pattern corresponding to the test chart 40 cannot be determined from the appearance.

Incidentally, such test data can be set, for example, as follows. First, using the K ink in the reference printer 36, a halftone (hereinafter referred to as K5) is printed on a recording medium.
0%) square pattern (for example, 2m in length and width)
m), and the K50% pattern is color-measured with a colorimeter, and colorimetric data CK50 represented by the XYZ color system (CIE 1931 color system) = (X ₅₀ , Y ₅₀ , Z ₅₀ ) Ask for.

Further, in a pattern having the same size as the K50% pattern, W (white: the color of the recording medium), C
(Cyan) ink color, M (magenta) ink color, Y (yellow) color, 3C (C, M, Y ink laminated) color, R
A (red) color, a G (green) color, and a B (blue) color are formed. Then, each pattern is measured with a colorimeter, and X
Each colorimetric data Cw, Cc, Cm, Cy, C3c, Cr, C expressed in the YZ color system (CIE 1931 color system)
g and Cb are determined.

Each of the obtained colorimetric data is represented by Cw
= (Xw, Yw, Zw), Cc = (Xc, Yc, Z
c), Cm = (Xm, Ym, Zm), Cy = (Xy, Y
y, Zy), C3c = (X3c, Y3c, Z3c), C
r = (Xr, Yr, Zr), Cg = (Xg, Yg, Z
g), Cb = (Xb, Yb, Zb).

By the way, while the character pattern is K50%, the background pattern is formed by laminating C, M, and Y inks and has the same color as K50%. Therefore,
Each color C, M, Y used to form a background pattern
The ink amounts are InkC, InkM, and InkY (however, 0 ≦ InkC, InkM, InkY ≦ 1, 1 is the maximum ink ejection, and 0 is no ink ejection).

In the background pattern, W (white: that is, the color of the recording medium) color, C (cyan) ink color, M (magenta) ink color, Y (yellow) color, and 3C (C, M,
Y ink layer), R (red), G (green), B (blue)
The area ratio of each color is defined as aw, ac, am, ay, a3c,
Expressed as ar, ag, ab.

The unknown is the area ratio a of each color of the background pattern.
w, ac, am, ay, a3c, ar, ag, ab,
Each ink amount InkC, Ink used in the background pattern
Since these are M and InkY, these unknowns can be obtained by solving simultaneous equations composed of the following equations (1) to (11).

[0030]

(Equation 1)

Aw, ac, am, ay, a3c, a are obtained by solving the simultaneous equations (1) to (11).
If r, ag, ab, InkC, InkM, and InkY are used, a background pattern can be formed in the same color as the K50% pattern.

Next, the test chart forming process executed by the CPU 10 will be described with reference to the flowchart shown in FIG. Note that a program for executing the test chart forming process is stored in the HDD 16 as one of the start programs of the PC 2 so as to be started first when the PC 2 is started. For this reason, the test chart forming process is always executed immediately after the PC 2 is started, and is also executed when the user instructs the execution of this process as needed.

As shown in FIG. 3, when this processing is started, first in S100 (S represents a step), the HDD
The test data is read from the data 16, converted into data for image formation (image formation data) based on the conversion characteristic data, output to the printer 36, and waits until the output of the data is completed in S 110. , And performs processing as test data output means.

According to this processing, the printer 36 prints the test chart on the recording paper set in advance, and the user can determine whether the print result is good or not, and further, the conversion characteristic data currently set. It can be visually determined whether or not the update is necessary. Therefore, when the completion of data output is confirmed in S110, in S120, a message for the user to input the result of the visual evaluation of the test chart, for example, a message such as "Do you want to perform calibration?" Is displayed on the monitor 34.

In step S130, the user operates the mouse 32 or the keyboard 30 in accordance with the message to wait for a command to update the conversion characteristic data. When it is instructed that the data is good and the update of the conversion characteristic data is unnecessary, the process is terminated. On the other hand, when the print result of the test chart is poor and the user inputs an instruction to update the conversion characteristic data, the process shifts to S140, executes the update processing of the conversion characteristic data, and ends the processing.

In the updating process of the conversion characteristic data, image forming data for printing a colorimetric test chart is output to a printer 36 in accordance with a command from a user.
A colorimetric test chart is printed on a predetermined recording sheet. Thereafter, the user sets the printed colorimetric test chart on the colorimeter 38 and sends the colorimetric test chart from the colorimeter 38. When the colorimetric data is input, a conversion corresponding to the current characteristics of the printer 36 is performed based on the colorimetric data and the image forming data of the colorimetric test chart. The characteristic data is obtained and HDD1
The conversion characteristic data in step 6 is rewritten.

As described above, in this embodiment, the PC 2
The test chart forming process is executed at the time of start-up or in response to a command from the user, and a test chart for visually confirming the necessity of updating the conversion characteristic data (in other words, calibration) is printed on the printer 36. It is made to let. Further, this test chart divides a predetermined image forming area on a recording sheet into a plurality of sections along a character pattern corresponding to a preset character string, and divides the character pattern and the background pattern into image forming materials. Is changed so that the same halftone color is obtained by changing the ink distribution.

For this reason, in the test chart after printing, if the printing result is good, the character pattern and the background pattern cannot be discriminated from each other.
The character string appears to be raised due to the color difference between the character pattern and the background pattern. Therefore, the user can judge whether or not the conversion characteristic data needs to be updated at a glance of the print result of the test chart, and performs the setting operation of the conversion characteristic data using the colorimeter 38 only when necessary. Will be able to do it. Further, it is only necessary to visually check the test chart printed by the printer 36 to determine whether or not the conversion characteristic data needs to be updated, and there is no need to perform a complicated operation such as a setting operation of the conversion characteristic data. Thus, the burden on the user can be reduced and the work efficiency of the user can be improved.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various embodiments can be adopted. For example, in the above embodiment, the test chart is described as being composed of a character pattern composed of a character string such as “Calibration” and a background pattern. However, the test chart is not limited to characters, but may be a combination of various symbols or marks, or a specific pattern. May be formed.

In the above embodiment, when printing the test chart on the printer 36, different inks are used for each pattern so that the character pattern and the background pattern have the same color, However, it is sufficient that each pattern such as a character and a background constituting the test chart can be visually judged as to whether or not the printing state is good. Therefore, the patterns may be printed in different colors.

In the above embodiment, the case where the function as the image processing apparatus of the present invention is incorporated in the personal computer 2 which outputs image forming data to the printer 36 and forms an image on a predetermined recording sheet has been described. But,
The function as the image processing apparatus of the present invention may be incorporated in the image forming apparatus itself such as a printer or a copying machine.

[Brief description of the drawings]

FIG. 1 is a main block diagram of a personal computer according to an embodiment.

FIG. 2 is an explanatory diagram showing a test chart.

FIG. 3 is a flowchart illustrating a test chart forming process.

[Explanation of symbols]

2 PC (personal computer), 4 computer section, 10 CPU, 12 ROM, 14 RAM, 1
6 HDD, 18 bus, 20, 22 interface, 30 keyboard, 32 mouse, 34 monitor
36: printer, 38: colorimeter, 40: test chart.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C262 AA24 AB11 AC07 BA17 EA07 EA08 EA12 FA13 5C077 LL12 LL17 MM27 MP08 PP33 PP37 PP38 PQ22 SS03 TT05 5C079 HA18 HB03 KA04 KA18 MA01 MA10 NA27 NA29 PA03

Claims (5)

[Claims] A conversion unit configured to convert image data into image formation data corresponding to an image formation characteristic of an external image forming apparatus; and a conversion characteristic data used by the conversion unit to convert the image data. An image capable of forming a color image on a recording medium using a plurality of image forming materials of different colors, comprising: a conversion characteristic storage unit for performing the conversion, and an output unit for outputting the image forming data to the image forming apparatus. In an image processing apparatus for forming a color image in a forming apparatus, test data storage means for storing test data used by a user to form a test chart used for visual evaluation in the image forming apparatus, and an external command Test data output to convert the test data into image forming data based on the conversion characteristic data and output the image data to the image forming apparatus. The test chart is a test chart in which one image forming area on the recording medium is divided into a plurality of parts by a predetermined pattern, and the image forming material or the distribution of the image forming materials is changed. An image processing apparatus, characterized in that: 2. The image processing apparatus according to claim 1, wherein the test chart determines the degree of color approximation for each of the regions by the visual evaluation. 3. The test chart according to claim 1, wherein, in the test chart, each of the areas is divided by a predetermined pattern representing a character or a graphic in order to identify the character or the graphic by the visual evaluation. 3. The image processing device according to 2. 4. The test data, for each of the areas,
The image processing according to any one of claims 1 to 3, wherein the setting is such that the same halftone color is formed by changing the distribution of the image forming materials or each image forming material. apparatus. 5. The test data output means, in addition to an external command, when the power of the image processing apparatus is turned on.
The image processing apparatus according to claim 1, wherein the test data is output from the output unit to the image forming apparatus.