JP2000032267A - Image processing method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processing method capable of flexibly coping with the characteristics of input and output images in the case of obtaining optimum images by using an arithmetic expression and an image processor capable of processing the various kinds of the input and output images at a low cost without increasing the circuit scale of an arithmetic means and a storage means. SOLUTION: Image data X are inputted to a first multiplier 2, a first subtractor 5 and a first adder 6. A constant generator 1 generates a1, a2 and a3 and respectively supplies them to the first multiplier 2, the first subtractor 5 and the first adder 6. The first multiplier 2 outputs a product a1.X, the first subtractor 5 outputs the difference (X-a2) and the first adder 6 outputs the sum (X+a3). A second multiplier 3 outputs the product a1.X.(X-a2), a divider 4 outputs the quotient a1.X.(X-a2)/(X+a3) and a second adder 7 outputs computed data Y1[=X+a1.X.(X-a2)/(X+a3)].

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 an image-related apparatus such as a TV or a VTR, an image-related apparatus such as a personal computer, and a printing apparatus such as a scanner or a printer. Related to the device.

In particular, image conversion processing for freely correcting the gradation characteristics of video data or image data by gradation calculation, and image data expressed in three colors of red / green / blue in three colors of yellow / magenta / cyan. A color conversion method and apparatus for performing data processing for converting print data represented by four inks including ink or black, or data processing for converting sensor data of a scanner into red / green / blue color separation data. It is about.

[0003]

2. Description of the Related Art First, an image information processing apparatus conventionally used in a display system of an information processing apparatus such as a computer will be described. FIG.
1 is an example of a conventional gradation processing apparatus disclosed in Japanese Patent Application Laid-Open No. 7-9072. 100 is a refresh pattern memory for storing image information as digital values, 101 is a table select circuit, and 102 is an R for storing arbitrary gradation correction information.
An AM (random access memory) 103 is a control unit for controlling the table select circuit 101 and the RAM 102.

This image information processing apparatus operates as follows. The RAM 102 has a plurality of correction tables, and each table stores correction data in advance. In the refresh pattern memory 100, digital image data X composed of a large number of pixel data constituting one screen is transferred from a computer main body (not shown) as image density information and is sequentially stored. The image data X read from the refresh pattern memory 100 is converted into composite address data having a function of selecting a correction characteristic by a table selection circuit 101, and data to be corrected Y corresponding to the image data X is obtained by table conversion in the RAM 102. Can be Note that the control unit 103 generates conversion characteristic selection data and the like, and the table selection circuit 101 and the RAM 1
02 timing control is performed.

[0005] In a normal image data configuration, the density of an image is expressed by 8 to 10 bits. Therefore, in order to execute one correction characteristic by table conversion, if it is 8 bits, 256 bytes (hereinafter abbreviated as B)
In the case of 10 bits, a memory capacity of 1 KB (kilobyte) is required. Therefore, the refresh pattern memory 100 has a 1200 gate scale with 8 bits,
A 10-bit RAM is realized by a 3000-gate RAM. Further, if the RAM is changed to the ROM, it can be realized with 400 gates and 700 gates, but the correction characteristics cannot be changed according to the image information.

Here, the image data includes not only image data for expressing a still image, but also video data for expressing a moving image, and these are hereinafter collectively referred to as image data.

As another conventional example relating to the tone conversion method and apparatus, Japanese Patent Publication No. Hei 3-81346 discloses a color image display method, Japanese Patent Publication No. Hei 4-41551 discloses a color density correction apparatus, and Japanese Patent Publication No. Japanese Patent Laying-Open No. 57-9072 discloses an image information processing apparatus.

FIG. 62 is a block diagram showing an embodiment of a conventional tone conversion device. In the drawing, reference numeral 104 denotes a density table to which a luminance signal Y read from a color original is input; 105, a density correction table; 106a to 106c, logarithmic converters to which color separation data (R, G, B) are input; 107a-c are adders, respectively.

This gradation conversion device operates as follows. A correspondence table between the luminance signal Y and the document density is obtained experimentally in advance, and the correspondence table is stored in the density table 104.
Thus, the density data Din of the input document corresponding to the luminance signal Y is obtained from the density table 104. In the density correction table 105, a correction amount α corresponding to the density data Din of the input document is obtained.

On the other hand, the color separation data (R, G, B) is obtained by scanning the input document, and the image data (R, G, B) color-separated into red, green, and blue. ) Are density data (D
r, Dg, Db). These density data are added to the correction amount α and the adders 107a to 107c to output density correction data (DR, DG, DB).

These red, green, and blue image data are also
The density correction table 105 has 8 to 10 bits, and the density correction table 105 requires a memory capacity of 256 B to 1 KB to execute one density correction characteristic by table conversion.

By the way, with respect to image data obtained from a color original of this type, it is necessary to perform not only gradation conversion processing but also color conversion processing for printing an optimum image. This is because image quality is deteriorated due to color mixing in the spectral characteristics of the ink and non-linearity in the transfer characteristics of the print, which are caused by the fact that the ink used for printing is not a pure color. Therefore, a color conversion technique is indispensable for correcting the image quality deterioration and outputting a print image having good color reproducibility to a printing press.

Conventionally, two systems of a color conversion technology, a matrix operation system and a table conversion system, have been developed. In the matrix operation method, the following expression (27) is used as a basic operation expression.

[0014]

(Equation 25)

Here, i = 1 to 3 and j = 1 to 3,
Y, M and C are print data, R, G and B are image data,
(Aij) is a color conversion coefficient matrix.

By the way, with a simple linear operation according to the equation (27), it is not possible to easily realize a good conversion characteristic that only compensates for the non-linearity in the transfer characteristic of the print for the print data.

A method of improving the color conversion characteristics is disclosed in, for example, Japanese Patent Publication No. 2-30226 (hereinafter, referred to as Japanese Patent Publication No. 2-30226), and employs the following matrix operation equation (28).

[0018]

(Equation 26)

Here, i = 1 to 3 and j = 1 to 10, Y, M, and C are print data, R, G, and B are image data, N is a constant, and (Dij) is a color conversion coefficient matrix. It is. .

In the matrix operation of this equation (28),
Since image data in which an achromatic component and a color component are mixed is directly used, mutual interference of calculations occurs. That is, changing one color conversion coefficient (matrix operator) affects not only the component or hue of interest.
For this reason, there is a problem that it is not easy to correct the deterioration of the image quality due to the color mixing property of the ink and to realize a good conversion characteristic.

One solution to this problem is disclosed in
No. 4,717,174 discloses a color conversion method. FIG. 63 is a block diagram showing an example of a conventional color conversion device. In the figure, 108 is a minimum value calculator, 10
9 is a subtractor, 110 is a coefficient generator, 111 is a matrix calculator, 112 is a ROM, and 113 is a synthesizer.

This color conversion device operates as follows.
The minimum value calculator 108 receives image data R, G, and B expressed in three colors of red, green, and blue for each pixel of interest.
The minimum value α of the two image data is output. Subtractor 109
Subtracts the difference between the image data and the minimum value from the subtraction data R1, G
1, and output as B1. This minimum value α corresponds to the achromatic component of the image data, and the subtraction data R1, G1, and B1 each correspond to the color component. The matrix calculator 111 receives the subtraction data and the coefficient generated by the coefficient generator 110, performs a matrix calculation represented by Expression (28), and outputs color ink data Ya, Ma, and Ca. R
The OM 112 outputs achromatic ink data Yb, Mb, and Cb by table conversion using the minimum value α as an input. The synthesizer 113 calculates the sum of the color component and the achromatic color component for each ink, so that Ya + Yb, Ma + Mb, C
a + Cb are output as print data Y, M, and C for yellow, magenta, and cyan, respectively.

According to this color conversion method, it is possible to eliminate the mutual interference of the operations generated between the color components and the achromatic color components. However, the mutual interference of the operations that occur between the hues in the color components remains unresolved.

On the other hand, according to the color conversion method based on the table conversion as shown in FIGS. 61 and 62, image data expressed in red, green and blue is input to a conversion table, and R
The print data Y,
M and C can be obtained. In this method, since any conversion characteristics can be adopted, there is an advantage that color conversion with excellent color reproducibility can be executed.

However, with a simple configuration in which print data Y, M, and C are stored for each combination of image data R, G, and B as a conversion table, the memory requires a large capacity of about 400 Mbits. Therefore, for example,
In the color conversion device disclosed in Japanese Patent Publication No. 0, a method for reducing the memory capacity is described, but the memory capacity still reaches about 5 Mbit. Therefore, this table conversion method requires a large-capacity memory for each conversion characteristic.
It was difficult to achieve SI, and it was not possible to flexibly respond to changes in printing conditions such as the use of another ink.

[0026]

As described above, the conventional image processing method and apparatus can perform only the gradation processing or the color conversion processing of the characteristic stored in advance in the table conversion means. For this reason, (A) gamma characteristic processing unique to video-related equipment, (B) matching (unification) of gradation characteristics among video-related equipment, image-related equipment, and printing-related equipment, (C) image contrast characteristics There has been a problem that the gradation characteristics cannot be arbitrarily changed in response to various requirements such as a gradation process corresponding to a human visual sensitivity characteristic and a preference.

Further, in order to realize various gradation characteristics, the memory capacity increases in proportion to the number of characteristics.
There is also a problem that becomes a hindrance factor when storing in I.

There is another problem that it is difficult to realize the same function by software.

Similarly, in the conventional color conversion method or color conversion apparatus, each hue cannot be independently corrected (corrected) depending on the matrix operation method. For this reason, there is a problem that mutual interference of calculations occurs between the hues, so that it is difficult to set a color conversion coefficient, and there is a problem that good conversion characteristics cannot be realized in all hues.

On the other hand, the color conversion method using the table conversion has a problem that a large-capacity memory is required similarly to the gradation correction, and a problem that the conversion characteristics cannot be flexibly changed.

The present invention has been made in order to solve the above-mentioned problems, and an image processing method capable of flexibly coping with the characteristics of an input image and an output image when obtaining an optimum image using an arithmetic expression. The purpose is to provide.

Another object of the present invention is to provide an image processing apparatus capable of processing various types of input and output images at a low cost without simultaneously increasing the circuit scale of the arithmetic means and the storage means. To provide.

In particular, when the operation target data Y is output by a gradation operation with the image data X as an input, an arbitrary gradation can be set according to the characteristics of the image or the user's preference only by changing the coefficient of the function operation. It is an object of the present invention to provide an image processing method and apparatus which can realize characteristics, can be easily formed into an LSI, and can execute the same processing by both hardware and software.

Further, image data R, G, B, etc. expressed in three colors of red, green, and blue are subjected to color conversion processing for each pixel,
Print data C, M, Y represented by four to four ink colors
, The six hue regions of the image data R, G, B and the print data Y, M, C are independently corrected (corrected).
It is another object of the present invention to provide an image processing method and apparatus capable of flexibly changing a conversion characteristic by a matrix operation and performing color conversion without requiring a large-capacity memory.

[0035]

According to a first aspect of the present invention, there is provided an image processing method for outputting data Y to be operated on by performing a gradation operation with image data X as an input. Setting a functional expression including at least two of a quadratic term, a tertiary term, or a multiplication / division term; and outputting the operand data Y based on the functional equation. And

According to a second aspect of the present invention, in the image processing method according to the first aspect, the operated data Y is a combination of the image data X and the constant a
Using 1, a2 and a3, Y = X + a1 · X · (X−a2) / (X + a3) (1) or Y = X · {1 + a1 · (X−a2) / (X + a3)} (2) It is characterized by being expressed.

According to a third aspect of the present invention, there is provided the image processing method according to the second aspect, wherein the image data X is input and the processing for outputting the operated data Y by the gradation operation is executed by a program. A) generating constants a1, a2, and a3; (B) obtaining difference (X-a2) and sum (X + a3) from image data and the constant;
(C) a step of obtaining a modification amount a1 · X · (X−a2) / (X + a3) from the image data, the difference and the sum, and the constant, and (D) an operation data Y from the image data and the modification amount.
, And

According to a fourth aspect of the present invention, there is provided an image processing method according to the second aspect, wherein the processing for outputting the operated data Y by a gradation operation using the image data X as an input is executed by a program. A) generating constants a1, a2, and a3; (B) obtaining difference (X-a2) and sum (X + a3) from image data and the constant;
(C) a step of obtaining a correction coefficient 1 + a1 · (X−a2) / (X + a3) from the image data, the difference and the sum, and the constant, and (D) a step of obtaining the operand data Y from the image data and the correction coefficient. It is characterized by having.

According to a fifth aspect of the present invention, in the image processing method according to the first aspect, the operation target data Y is obtained by using the image data X and the constants a1, a2, a3, and a4, so that Y = X + a1 · X · ( X−a2) · (X−a3) / (X + a4) (3) or Y = X · {1 + a1 · (X−a2) · (X−a3) / (X + a4)} (4) It is characterized by the following.

According to a sixth aspect of the present invention, there is provided an image processing method according to the fifth aspect, wherein the processing of outputting the operated data Y by a gradation operation using the image data X as an input is executed by a program. A) Constants a1, a2, a3,
generating a4, (B) obtaining a difference (X-a2), (X-a3) and a sum (X + a4) from the image data and the constant, and (C) using the image data, the difference and the sum and the constant. Modification amount a1, X, (X-a2), (X-a
3) obtaining (X + a4); (D) obtaining data Y to be operated on from image data and the modification amount;
It is characterized by having.

According to a seventh aspect of the present invention, there is provided an image processing method according to the fifth aspect, wherein a process for outputting the operated data Y by a gradation operation using the image data X as an input is executed by a program. A) Constants a1, a2, a3,
generating a4, (B) obtaining a difference (X-a2), (X-a3) and a sum (X + a4) from the image data and the constant, and (C) modifying coefficient 1 + a1 from the difference and the sum and the constant.・ (X-a2) ・ (X-a3) / (X +
a4), and (D) a step of calculating the operated data Y from the image data and the modification coefficient.

In the image processing method according to the present invention, the data to be operated Y described in claim 1 is a combination of the image data X and the constant a.
Using 1, a2, a3, a4, and a5, Y = X + a1.X. (X-a2) + a3.X. (X-a2). (X-a4) / (X + a5) (5) or Y = X · {1 + a1 · (X−a2) + a3 · (X−a2) · (X−a4) / (X + a5)} (6)

According to a ninth aspect of the present invention, there is provided an image processing method according to the eighth aspect, wherein the processing of outputting the operated data Y by a gradation operation using the image data X as an input is executed by a program. A) Constants a1, a2, a3,
generating a4, a5, (B) the difference (X-a2), (X-a4) and the sum (X + a) from the image data and the constant.
5C), (C) a modification amount a1, X, (X-a2) + a3 from the image data, the difference and the sum, and the constant.
A step of obtaining X · (X−a2) · (X−a4) / (X + a5); and (D) a step of obtaining data Y to be operated on from image data and the amount of modification.

According to a tenth aspect of the present invention, there is provided an image processing method according to the eighth aspect, wherein a process for outputting the data to be operated Y by a gradation operation using the image data X as an input is executed by a program. A) Constants a1, a2, a
(B) generating a difference (X−a2), (X−a4) and a sum (X) from the image data and the constant.
+ A5); (C) modifying coefficient 1 + a1 · (X−a2) + a3 · (X
−a2) · (X−a4) / (X + a5); and (D) a step of calculating the operated data Y from the image data and the modification coefficient.

The image processing method according to the eleventh aspect is characterized in that the converted data Y according to the first aspect is obtained by converting the image data X into a constant a
By using 1, a2, and a3, Y = X-a1.X. (X-a2). (X-a3) (7) or Y = X..SIGMA.1-a1. (X-a2). (X −a3)｝ (8)

According to a twelfth aspect of the present invention, there is provided the image processing method according to the eleventh aspect, wherein the image data X is input and the converted data Y is output by a gradation calculation using a program. A) Constants a1, a2, a
(B) determining the differences (X-a2) and (X-a3) from the image data and the constants;
(C) A modification amount a1 · from the image data, the difference, and the constant.
A step of obtaining X · (X−a2) · (X−a3);
(D) obtaining data to be converted Y from the image data and the amount of modification.

According to a thirteenth aspect of the present invention, there is provided an image processing method according to the eleventh aspect, wherein a process of outputting converted data Y by a gradation operation using the image data X as an input is executed by a program. A) Constants a1, a2, a
(B) determining the differences (X-a2) and (X-a3) from the image data and the constants;
(C) From the difference and the constant, the modification coefficient 1−a1 · (X−
a2) · (X−a3); and (D) a step of obtaining converted data Y by multiplying the image data by the modification coefficient.

According to a fourteenth aspect of the present invention, in the image processing method according to the first aspect, the converted data Y is obtained by using the image data X and the constants a2, a3, a4, and a5, and Y = XX- ( X−a3) · {a4 · (X−a2) + a5 · | X−a2 |} (9) or Y = X · [1− (X−a3) · ｛a4 · (X−a2) + a5 · | X−a2 |｝] (10)

According to a fifteenth aspect of the present invention, there is provided an image processing method according to the fourteenth aspect, wherein a process for outputting converted data Y by a gradation operation with the image data X as an input is executed by a program. A) Constants a2, a3, a
(B) differences (X-a2), (X-a3) and absolute values | from the image data and the constants.
X-a2 |, and (C) a modification amount X · (X−) from the image data, the constant, the difference, and the absolute value.
a3) ｛{a4 ・ (X-a2) + a5 ・ | X-a2｝
, And (D) a step of obtaining the converted data Y from the image data and the amount of modification.

According to a sixteenth aspect of the present invention, there is provided an image processing method according to the fourteenth aspect, wherein a process for outputting converted data Y by a gradation operation with the image data X as an input is executed by a program. A) Constants a2, a3, a
(B) differences (X-a2), (X-a3) and absolute values | from the image data and the constants.
(C) modifying coefficient 1− (X−a3) · ｛a4 · from the constant, the difference, and the absolute value.
(X−a2) + a5 · | X−a2 |｝, and (D) a step of obtaining converted data Y by multiplying the image data by the modification coefficient.

According to a seventeenth aspect of the present invention, in the image processing method according to the first aspect, the data to be converted Y according to the first aspect uses the image data X, the threshold value h, and the constants a1, a2, a3, a4, and a5.
When X ≦ h, Y = X−a1 · X · (X−h) · (X−a3) (11) When X> h, Y = X−a2 · (X−h) · (X− a4) · (X−a5) (12)

An image processing method according to an eighteenth aspect of the present invention is the image processing method according to the seventeenth aspect, wherein the processing for outputting the converted data Y by a gradation operation with the image data X as an input is executed by a program. A) Threshold h and constant a
Generating 1, a2, a3, a4, a5;
(B) The difference between the image data, the threshold value, and the constant (X
-H), (Xa3), (Xa4), (Xa5), (C) comparing the image data with the threshold, and (D) comparing the image data. From the constant and the difference, when X ≦ h, a
1 · X · (X−h) · (X−a3), when X> h, a
2. A step of obtaining a modification amount of (Xh). (X-a4). (X-a5); and (E) a step of obtaining conversion target data Y from image data and the modification amount. And

According to a nineteenth aspect of the present invention, in the image processing method according to the first aspect, the converted data Y is output by performing a gradation operation with the image data X as an input. Data X, threshold h and constant a
By using 1, a2 and a3, when X ≦ h, Y = X−a1 · X · (X−h) (13) When X> h, Y = X−a2 · (X−h) · (X-a3)... (14)

According to a twentieth aspect of the present invention, there is provided an image processing method according to the nineteenth aspect, wherein a process for outputting converted data Y by a gradation operation with the image data X as an input is executed by a program. A) Threshold h and constant a
(B) differences (X-h), (X-a) between image data, the threshold value, and the constant.
3) determining (C) comparing the image data with the threshold value; (D) according to the comparison result of the image data, from the constant and the difference, when X ≦ h, a1 X. (Xh), when X> h, a2. (X
-H) a step of obtaining a modification amount of (X-a3);
(E) obtaining the converted data Y from the image data and the modification amount.

The image processing method according to the twenty-first aspect is the second, fifth, eighth, eleventh, fourteenth, and fourteenth aspects of the present invention.
20. The data Y to be converted by the gradation operation using the image data X according to claim 17 or 19 as an input.
Is characterized by realizing a plurality of gradation conversion characteristics by changing a constant or a threshold value unique to each functional expression.

The image processing method according to claim 22 is the image processing method according to claim 3, claim 4, claim 6, claim 7, claim 9, claim 10, claim 12, claim 13, claim 15, 21. An image processing method according to claim 16, wherein the processing for outputting converted data Y by a gradation operation using the image data X as an input is executed by a program. The method includes a step of changing a constant or a numerical value of a threshold value unique to the equation, and realizes a plurality of gradation conversion characteristics.

According to a twenty-third aspect of the present invention, in the image processing method, the data Y to be operated on by the gradation operation with the image data X as an input.
In the image processing method for outputting the image data X, a step of setting a function expression including a logarithmic term of the image data X, and a step of outputting the operated data Y based on the function expression,
It is characterized by having.

According to a twenty-fourth aspect of the present invention, the image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel, and the three ink colors of cyan, magenta, and yellow are obtained. (A) generating complementary color data Ci, Mi, Yi from image data R, G, B in an image processing method for outputting print data C, M, Y represented by
(B) a step of obtaining the following minimum value α and maximum value β from the complementary color data: α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3; j = 1 to 3 (Fij) is i = 1 to 3; j = 1 to 12 (E) By a matrix operation according to the following equation (15) Obtaining print data C, M, Y;

[Equation 27] It is characterized by having.

According to a twenty-fifth aspect of the present invention, the matrix operation of the step (E) according to the twenty-fourth aspect is performed by the following equation (1).
It is characterized in that it is executed by the following equation (16) instead of 5).

[Equation 28]

According to a twenty-sixth aspect of the present invention, the matrix operation of the step (E) according to the twenty-fourth aspect is performed by the following equation (1).
In place of 5), the following equation (17) or this equation (17)
In which the (r + c) term is replaced with a (g + m) term or a (b + y) term.

(Equation 29)

According to a twenty-seventh aspect of the present invention, the image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel, and the three ink colors of cyan, magenta, and yellow are obtained. (A) generating complementary color data Ci, Mi, Yi from image data R, G, B in an image processing method for outputting print data C, M, Y represented by
(B) a step of obtaining the following minimum value α and maximum value β from the complementary color data: α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3; j = 1 to 3 (Fij) is i = 1 to 3; j = 1 to 14 (E) The matrix operation expression of the following expression (18) Obtaining print data C, M, and Y by

[Equation 30] It is characterized by having.

According to a twenty-eighth aspect of the present invention, the matrix operation of step (E) according to the twenty-seventh aspect is performed by the following equation (1).
It is characterized in that it is executed by the following equation (19) instead of 8).

(Equation 31)

A method according to a twenty-ninth aspect is a method according to the twenty-seventh aspect, wherein the matrix operation of step (E) according to the twenty-seventh aspect is represented by the following equation (1).
In place of 8), the following equation (20) or this equation (20)
In which the (r + c) term is replaced with a (g + m) term or a (b + y) term.

(Equation 32)

The method according to claim 30 is the method according to claim 24,
The sensor data Rin, Gin, Bin represented by three colors of red, green, and blue according to any one of claims 25, 26, 27, 28, and 29, for each pixel. After performing color conversion processing, the color separation data Rout, Gou
In the image processing method for outputting t and Bout, the image data C, M, and Y in the step (A) or the generated complementary color data Ci, Mi, and Yi are converted into sensor data Rin,
Gin, Bin, and the color separation data Rout, Gout, Bout are obtained in the step (E).

According to a thirty-first aspect of the present invention, image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel, and are converted into four colors of cyan, magenta, yellow, and black. Print data C, M, Y, represented by ink colors
In the image processing method for outputting K, (A) a step of generating complementary color data Ci, Mi, and Yi from image data R, G, and B; and (B) a step of obtaining the following minimum value α and maximum value β from the complementary color data: , Α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) a step of dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Ei
(Eij), i = 1 to 3, j = 1 to 3 (Fij), i = 1 to 3, j = 1 to 12 (F) The following equation (Fij) 21) obtaining print data C, M, and Y by matrix operation according to 21);

[Equation 33] It is characterized by having.

A method according to claim 32 is characterized in that the matrix operation of step (F) according to claim 31 is performed by the following equation (2).
It is characterized in that it is executed by the following equation (22) instead of 1).

(Equation 34)

A method according to a thirty-third aspect is characterized in that the matrix operation in the step (F) according to the thirty-first aspect is performed by the following equation (2).
In place of 1), the following equation (23) or this equation (23)
In which the (r + c) term is replaced with a (g + m) term or a (b + y) term.

(Equation 35)

According to a thirty-fourth aspect, the image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel, and are converted into four colors of cyan, magenta, yellow, and black. Print data C, M, Y, represented by ink colors
In the image processing method for outputting K, (A) a step of generating complementary color data Ci, Mi, and Yi from image data R, G, and B; and (B) a step of obtaining the following minimum value α and maximum value β from the complementary color data: , Α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) a step of dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Ei
(Eij), i = 1 to 3, j = 1 to 3 (Fij), i = 1 to 3, j = 1 to 14 (F) The following equation (F) 24) a step of obtaining print data C, M, Y by a matrix operation formula of

[Equation 36] It is characterized by having.

A method according to a thirty-fifth aspect of the present invention is a method according to the thirty-fourth aspect, wherein the matrix operation of step (F) is performed by the following equation (2).
It is characterized in that it is executed by the following equation (25) instead of 4).

(37)

A method according to a thirty-sixth aspect is characterized in that the matrix operation in the step (F) according to the thirty-fourth aspect is performed by the following equation (2).
In place of 4), the following equation (26) or this equation (26)
In which the (r + c) term is replaced with a (g + m) term or a (b + y) term.

(38)

In the image processing apparatus according to the present invention, the data Y to be operated on by the gradation operation with the image data X as an input.
Means for setting a function formula including at least two of a first-order term, a second-order term, or a third-order term, and a multiplication / division term of the image data X; Means for outputting operation data Y.

An image processing apparatus according to a thirty-eighth aspect of the present invention is an image processing apparatus according to the thirty-seventh aspect, wherein data to be operated on is output by a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2 and a3; (B) difference (X-a2) and sum (X + a) from image data and the constants
(C) means for calculating (a) a modification amount a1 · X · (X−a2) / (X + a) from the image data, the difference and the sum, and the constant;
3), and (D) means for calculating the operated data Y from the image data and the amount of modification.

An image processing apparatus according to a thirty-ninth aspect is the image processing apparatus according to the thirty-seventh aspect, wherein the operated-data Y is output by a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2 and a3; (B) difference (X-a2) and sum (X + a) from image data and the constants
(C) means for obtaining the correction coefficient 1 + a1 · (X−a2) / (X +) from the image data, the difference and the sum, and the constant.
a3), and (D) means for calculating the operated data Y from the image data and the modification coefficient.

The image processing apparatus according to claim 40 is the image processing apparatus according to claim 37, wherein the operation target data Y is output by a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2, a3, a4;
(B) The difference (X-a2), (X
(C) means for calculating the sum (X + a4) and the sum (X + a4);
Means for calculating (X-a2) · (X-a3) / (X + a4); (D) the data Y to be operated on from the image data and the modification amount
And means for determining

The image processing apparatus according to claim 41 is the image processing apparatus according to claim 37, which outputs the data Y to be operated by performing a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2, a3, a4;
(B) The difference (X-a2), (X
(C) a modification coefficient 1 + a1 · (X−a2) from the difference and the sum and the constant;
A means for calculating (X-a3) / (X + a4); and (D) means for calculating data Y to be operated on from image data and the modification coefficient.

The image processing apparatus according to claim 42 is an image processing apparatus according to claim 37, which outputs the data Y to be operated by performing a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2, a3, a4, a5, (B) difference (X-a2) from image data and the constants,
Means for calculating (X-a4) and the sum (X + a5); (C) a modification amount a1 · X from the image data, the difference and the sum, and the constant;
· (X-a2) + a3 · (X-a2) · (X-a4) /
(D) means for calculating (X + a5), and (D) means for calculating the operated data Y from the image data and the amount of modification.

An image processing apparatus according to a thirty-seventh aspect is an image processing apparatus according to the thirty-seventh aspect, wherein data to be operated on is output by a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2, a3, a4, a5, (B) difference (X-a2) from image data and the constants,
Means for calculating (X-a4) and the sum (X + a5); (C) modifying coefficient 1 + a1 · (X-a) from the difference and the sum and the constant;
2) + a3 · (X-a2) · (X-a4) / (X + a
5), and (D) means for calculating the operated data Y from the image data and the modification coefficient.

The image processing apparatus according to claim 44 is the image processing apparatus according to claim 37, wherein the converted data Y is output by a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2 and a3; (B) differences (X-a2) and (X-a3) between image data and the constants
(D) means for calculating a modification amount a1, X, (X-a2), (X-a3) from image data, the difference and the constant, and (D) conversion data from the image data and the modification amount. Means for obtaining Y.

An image processing apparatus according to a forty-fifth aspect of the present invention is an image processing apparatus according to the thirty-seventh aspect for outputting converted data Y by performing a gradation operation with the image data X as an input.
(A) means for generating constants a1, a2 and a3; (B) differences (X-a2) and (X-a3) between image data and the constants
(C) modifying coefficient 1 from the difference and the constant.
Means for determining -a1 · (X−a2) · (X−a3),
(D) means for obtaining the converted data Y by multiplying the image data by the modification coefficient.

The image processing apparatus according to claim 46 is the image processing apparatus according to claim 37, wherein the converted data Y is output by a gradation operation using the image data X as an input.
(A) means for generating constants a2, a3, a4, a5;
(B) The difference (X-a2), (X
-A3) and means for determining the absolute value | X-a2 |
(C) A modification amount X · (X−a3) · ｛a4 · (X−a2) + a5 from the image data, the constant, the difference, and the absolute value.
. | X-a2 |}, and (D) means for obtaining the converted data Y from the image data and the amount of modification.

The image processing apparatus according to claim 47 is the image processing apparatus according to claim 37, wherein the converted data Y is output by a gradation operation with the image data X as an input.
(A) means for generating constants a2, a3, a4, a5;
(B) The difference (X-a2), (X
-A3) and means for determining the absolute value | X-a2 |
(C) From the constant, the difference, and the absolute value, a modification coefficient 1− (X−a3) · ｛a4 · (X−a2) + a5 · | X−a
2 |｝, and (D) means for obtaining the transformed data Y by multiplying the image data by the modification coefficient.

The image processing apparatus according to claim 48 is the image processing apparatus according to claim 37, wherein the converted data Y is output by a gradation operation with the image data X as an input.
(A) Threshold value h and constants a1, a2, a3, a4, a5
(B) differences (Xh), (Xa3), (Xa) from the image data, the threshold value and the constant.
4), means for obtaining (X-a5), (C) means for comparing the magnitude of the threshold with the image data, and (D) X from the constant and the difference according to the comparison result of the image data. ≤
When h, a1 · X · (X−h) · (X−a3), X>
When h, a2ａ (Xh) ・ (Xa4) ・ (Xa
5) a step of obtaining a modification amount, and (E) means for obtaining data to be converted Y from image data and the modification amount.

An image processing apparatus according to claim 49 is an image processing apparatus according to claim 37, wherein the converted data Y is output by a gradation operation using the image data X as an input.
(A) means for generating a threshold value h and constants a1, a2, and a3; (B) means for obtaining differences (Xh) and (Xa3) from image data, the threshold value, and the constant; (C) means for comparing image data with the threshold value, (D)
According to the comparison result of the image data, from the constant and the difference, when X ≦ h, a1 · X · (X−h), and when X> h, a2 · (X−h) · (X− a3) a step of obtaining a modification amount; and (E) means for obtaining data to be converted Y from image data and the modification amount.

The image processing apparatus according to claim 50 is the image processing apparatus according to claim 38, claim 39, claim 40, claim 41, claim 42, claim 43, claim 44, claim 45, and claim 4.
6. An image processing apparatus according to any one of claims 47, 48, and 49, which outputs converted data Y by a gradation operation with the image data X as an input, wherein each function expression has There is provided a means for changing a constant or a numerical value of a threshold value, and realizes a plurality of gradation conversion characteristics.

An image processing apparatus according to claim 51, wherein (A) means for selecting image data and address data, and (B) writing, in the image processing apparatus for outputting converted data Y by table conversion of image data X Means for switching the transfer direction of data and read data; (C) writable memory means; (D) means for generating write data by function operation; (E) means for generating the address data; Means for controlling each of the operations (A) to (E).

The image processing apparatus according to the fifty-second aspect is characterized in that the data Y to be operated on by the gradation operation with the image data X as an input.
An image processing apparatus that outputs a function expression including a logarithmic term of the image data X, and a unit that outputs the operated data Y based on the function expression. .

The image processing apparatus according to claim 53 is characterized in that:
Image data R, G, and B represented by three colors of green and blue are subjected to color conversion processing for each pixel, and print data C, M, and Y represented by three ink colors of cyan, magenta, and yellow are output. In the image processing apparatus, (A) image data R,
Means for generating complementary color data Ci, Mi, Yi from G and B, (B) means for obtaining the following minimum value α and maximum value β from the complementary color data, α = MIN (Ci, Mi, Yi), β = MAX ( Ci,
(Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3, j = 1 to 3 (Fij) is i = 1 to 3 and j = 1 to 12 (E) The matrix operation expression of the following expression (15) Means for obtaining print data C, M, Y by

[Equation 39] It is characterized by having.

An image processing apparatus according to a 54th aspect is characterized in that the matrix operation of the means (E) according to the 53rd aspect is executed by the following equation (16) instead of the equation (15). .

(Equation 40)

An image processing apparatus according to a thirty-fifth aspect of the present invention provides the image processing apparatus according to the fifty-third aspect, wherein the matrix operation of the means (E) is replaced by the following equation (17) or
7) The (r + c) term is replaced with the (g + m) term or (b + y)
It is characterized in that it is executed by replacing the term.

[Equation 41]

An image processing apparatus according to claim 56, wherein:
Image data R, G, and B represented by three colors of green and blue are subjected to color conversion processing for each pixel, and print data C, M, and Y represented by three ink colors of cyan, magenta, and yellow are output. In the image processing apparatus, (A) image data R,
Means for generating complementary color data Ci, Mi, Yi from G and B, (B) means for obtaining the following minimum value α and maximum value β from the complementary color data, α = MIN (Ci, Mi, Yi), β = MAX ( Ci,
Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3, j = 1 to 3 (Fij) is i = 1 to 3 and j = 1 to 14 (E) The matrix operation expression of the following expression (18) Means for obtaining print data C, M, Y by

(Equation 42) It is characterized by having.

An image processing apparatus according to a 57th aspect is characterized in that the matrix operation of the means (E) according to the 56th aspect is executed by the following equation (19) instead of the equation (18). .

[Equation 43]

The image processing apparatus according to claim 58 uses the following equation (20) instead of the equation (18) in the matrix operation of the means (E) according to claim 56, or this equation (2).
The (r + c) term of (0) is replaced with the (g + m) term or (b + y)
It is characterized in that it is executed by replacing the term.

[Equation 44]

The image processing apparatus according to claim 59, wherein the red, green, and blue colors according to any one of claims 53, 54, 55, 56, 57, and 58 are provided. Sensor data Rin, Gin, Bi expressed in three colors
n is subjected to color conversion processing for each pixel, and color separation data Rou
In the image processing apparatus that outputs t, Gout, and Bout, the image data C, M, and Y of the means (A) or the generated complementary color data Ci, Mi, and Yi are converted into sensor data R.
in, Gin, and Bin, and the means (E) obtains the color separation data Rout, Gout, and Bout.

An image processing apparatus according to claim 60 is characterized in that
Image data R, G, and B represented by three colors, green and blue, are subjected to color conversion processing for each pixel to obtain cyan, magenta, yellow,
Print data C represented by four black ink colors,
In an image processing apparatus that outputs M, Y, and K, (A) means for generating complementary color data Ci, Mi, and Yi from image data R, G, and B, and (B) the following minimum value α and maximum value from complementary color data: means for determining β, α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) means for dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Eij)
(Eij) is i = 1 to 3, j = 1 to 3 (Fij) is i = 1 to 3, j = 1 to 12 (F) The following equation (21) Means for obtaining print data C, M, Y by a matrix operation formula of

[Equation 45] It is characterized by having.

An image processing apparatus according to claim 61 is characterized in that the matrix operation of means (F) according to claim 60 is executed by the following equation (22) instead of equation (21). .

[Equation 46]

The image processing apparatus according to claim 62 uses the following formula (23) instead of formula (21), or the formula (2), instead of the formula (21).
3) The (r + c) term is replaced with the (g + m) term or (b + y)
It is characterized in that it is executed by replacing the term.

[Equation 47]

The image processing apparatus according to claim 63 is characterized in that:
Image data R, G, and B represented by three colors, green and blue, are subjected to color conversion processing for each pixel to obtain cyan, magenta, yellow,
Print data C represented by four black ink colors,
In an image processing apparatus that outputs M, Y, and K, (A) means for generating complementary color data Ci, Mi, and Yi from image data R, G, and B, and (B) the following minimum value α and maximum value from complementary color data: means for determining β, α = MIN (Ci, Mi, Yi), β = MAX (Ci,
(Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) means for dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Eij)
(Eij) is i = 1-3, j = 1-3 (Fij) is i = 1-3, j = 1-14 (F) The following equation (24) Means for obtaining print data C, M, Y by a matrix operation formula of

[Equation 48] It is characterized by having.

An image processing apparatus according to a sixty-fourth aspect is characterized in that the matrix operation of the means (F) according to the sixty-third aspect is executed by the following equation (25) instead of the equation (24). .

[Equation 49]

The image processing apparatus according to claim 65 uses the following formula (26) instead of the formula (24) or the formula (2) instead of the formula (24).
6) The (r + c) term is replaced with the (g + m) term or (b + y)
It is characterized in that it is executed by replacing the term.

[Equation 50]

An image processing apparatus according to claim 66 is characterized in that:
In an image processing apparatus that performs color conversion processing on image data R, G, and B expressed in three colors of green and blue for each pixel and outputs print data, (A) color conversion processing for print data is performed in three colors Means for selecting either conversion or four-color conversion; (B) means for selecting use or non-use of a nigori removal function in color conversion processing; and (C) use or non-use of a fine adjustment function for achromatic components. (D) means for selecting the setting of a constant corresponding to the fine adjustment function, (E) means for selecting the setting of the constant corresponding to the division function, and (F) setting of the operation coefficient corresponding to a plurality of ink sets. , And at least one selection means.

An image processing apparatus according to claim 67, which performs color conversion processing on image data for each pixel and outputs print data, display data, color separation data, or other types of image data. (A) means for converting image data R, G, and B represented by three colors of red, green and blue into print data; (B) image data R and G represented by three colors of red, green and blue , B to display data; (C) means to convert image data from the sensor into color separation data or image data R, G, B expressed in three colors of red, green, and blue; (D) Means for converting the first type of image data into second type of image data; (E) means for converting the first type of print image data into the second type of print image data; F) The image data for the first type of color separation is
Means for converting into image data for color separation of the type (G)
Converting at least one of the means for converting the color reproduction characteristics in a combination of at least three types of data of color separation data, image data, print data, and display data into unified or matched color reproduction characteristics; It is characterized by having.

An image processing apparatus according to claim 68, wherein a specific processing characteristic is selected from a plurality of processing characteristics, image processing is performed on the image data, and data Y to be operated is output. Means for selecting the processing characteristics based on the characteristics of the input device and the characteristics of the output device, a conversion function according to the selected processing characteristics, and means for changing and setting numerical values of various constants of the conversion function, It is characterized by having. The image processing device according to claim 69, which is used as an input of a selected first device, or performs processing on input image data X output from the first device, and In an image processing apparatus for generating converted data Y used as an input of the second apparatus, each corresponding to a different combination of the first apparatus and the second apparatus,
A memory means for storing a plurality of processing characteristics for directly converting the input image data X into the converted data Y; and further comprising a memory means for storing a plurality of processing characteristics in accordance with a selected first device and a second device. Selecting means for selecting one of the plurality of processing characteristics stored in the means, and the input image data X and the converted image data based on the selected single processing characteristic according to the selecting means. Means for changing and setting one of a conversion function and a constant for a single-step conversion between data Y. The image processing device according to claim 70 is the image processing device according to claim 69, wherein
Is a display device or an image reading device.

[0103]

According to the image processing method of the first aspect, the primary component, the secondary component, and the multiplication / division component can be given to the gradation characteristics by the primary term, the quadratic term, and the multiplication / division term.

According to the image processing method of the second aspect,
The constant a2 determines the value of the image data X that satisfies Y = X, and the constants a1 and a3 determine the amount of change in the operated data Y from the image data X. Therefore, if the constants a1, a2, and a3 are changed, gradation processing with arbitrary characteristics can be executed.

According to the image processing method of the third aspect,
Image data X and modification amount a1.X. (X-a2) / (X +
3. The data Y to be operated on is obtained by adding a3).
Can be executed by a program.

According to the image processing method of the fourth aspect,
Image data X and modification coefficient ｛1 + a1 · (X−a2) /
(X + a3)} to obtain the operand data Y by multiplication,
The function operation according to claim 2 can be executed by a program.

According to the image processing method of the fifth aspect,
The constants a2 and a3 determine the value of the image data X where Y = X, and the constants a1 and a4 determine the amount of change of the data Y to be operated from the image data X. Therefore, constants a1, a2, a
By changing 3 and a4, gradation processing with arbitrary characteristics can be executed.

According to the image processing method of the sixth aspect,
The image data X and the modification amounts a1, X, (X-a2), (X-
a3) / (X + a4) is obtained to obtain the operated data Y, and the function operation according to claim 5 can be executed by a program.

According to the image processing method of the seventh aspect,
Image data X and modification coefficient ｛1 + a1 · (X−a2) ·
The data to be operated Y is obtained by multiplication of (X−a3) / (X + a4), and the function operation according to claim 5 can be executed by a program.

According to the image processing method of the eighth aspect,
The constants a2 and a4 determine the value of the image data X where Y = X, and the constants a1, a3 and a5 determine the amount of change of the operated data Y from the image data X. Therefore, constants a1, a
By changing 2, a3, a4, and a5, gradation processing with arbitrary characteristics can be executed.

According to the image processing method of the ninth aspect,
Image data X and modification amount ｛a1 · X · (X−a2) + a3
X · (X−a2) · (X−a4) / (X + a5)} is obtained to obtain the operated data Y, and the function operation according to claim 8 is executed by a program.

According to the image processing method of the present invention, the image data X and the modification coefficient ｛1 + a1 · (X−a2)
+ A3. (X-a2). (X-a4) / (X + a5)}
To obtain the operated data Y, and execute the function operation according to claim 8 by a program.

According to the image processing method of the present invention, the value of the image data X where Y = X is determined by a2 and a3. Also, the magnitude of the change of the converted data Y from the image data X is determined by a1. Therefore, a1, a
The gradation conversion characteristic is determined by three constants, 2 and a3.

According to the image processing method of the twelfth aspect, the image data X and the modification amount a1.X. (X-a2).
Data X to be operated is obtained by subtracting (X-a3), and the function operation according to claim 11 is executed by a program.

According to the image processing method of the thirteenth aspect, the image data X and the modification coefficient ｛1−a1 · (X−a2)
The data to be operated on is obtained by multiplication of (X−a3)}, and the function operation according to claim 11 is executed by a program.

According to the image processing method of the present invention, the value of the image data X where Y = X is determined by a2 and a3. Further, assuming that 0 <a2 <a3, the magnitudes of changes of the converted data Y from the image data X in the area of X <a2 and the area of X> a2 are a4-a5 and a4, respectively.
4 + a5. Therefore, a2, a3, a
The gradation conversion characteristic is determined by four constants of 4, a5.

According to the image processing method of the fifteenth aspect, the image data X and the modification amount X · (X−a3) · ・ a4 ·
The data Y to be operated is obtained by subtracting (X-a2) + a5 · | X-a2 |｝, and the function operation according to claim 14 is executed by a program.

According to the image processing method of the present invention, the image data X and the modification coefficient [1− (X−a3) · ｛a
4 · (X−a2) + a5 · | X−a2 |｝] to obtain the operand data Y, and the function operation according to claim 14 is executed by a program.

According to the image processing method of the present invention, the value of the image data X where Y = X is determined by h, a3, a4 and a5. Also, the magnitude of the change of the converted data Y from the image data X in the area of X <h and the area of X> h is determined by a1 and a2, respectively. Therefore, the gradation conversion characteristic is determined by the six constants h, a1, a2, a3, a4, and a5.

According to the image processing method of the eighteenth aspect, when the image data X and X ≦ h, a1 · X · (X−
h) · (X−a3), when X> h, a2 · (X−h)
The operation data Y is obtained by subtracting the (X-a4) and (X-a5) from the modification amount, and the function operation according to claim 17 is executed by a program.

According to the image processing method of the nineteenth aspect, the value of the image data X where Y = X is determined by h and a3. Also, the magnitude of the change of the converted data Y from the image data X in the area of X <h and the area of X> h is determined by a1 and a2, respectively. Also, the magnitude of the change of the converted data Y from the image data X in the area of X <h and the area of X> h is determined by a1 and a2, respectively. Therefore, the gradation conversion characteristic is determined by the four constants h, a1, a2, and a3.

According to the image processing method of the twentieth aspect, when image data X and X ≦ h, a1 · X · (X−
h), when X> h, a2 · (X−h) · (X−a3)
The arithmetic operation data Y is obtained by subtraction from the modification amount, and the function operation according to claim 19 is executed by a program.

According to the image processing method of the twenty-first aspect, the constants or functions of the functions of the second, fifth, eighth, eleventh, fourteenth, fourteenth, and seventeenth aspects are defined. By changing the numerical value of the threshold value, it is possible to freely adjust the gradation conversion characteristics according to tastes and image characteristics.

According to the image processing method described in claim 22, claims 3, 4, 6, 6, 7, 9, 10, 12, 13, and 13. 1
A plurality of gradation conversion characteristics can be realized by changing the constant of the function or the numerical value of the threshold value and executing the program by a program according to claim 16, claim 18, or claim 20.

According to the image processing method of the twenty-third aspect, the function operation expression for gradation conversion can be calculated by an approximate value of logarithmic operation. Since the visibility characteristics of humans can be approximated by logarithmic characteristics, it is suitable, for example, for gradation processing of color separation data in a scanner device.

According to the method of the twenty-fourth aspect, in step (B), the minimum value α is determined as the achromatic component of the print data, and is separated from the color component of the print data in step (C). Depending on the step, matrix operators α, c, m, y, r,
g and b are obtained. Then, by the matrix operation in step (E), the operation of the ideal ink without color mixture in the first term is performed, and the correction (modification) operation on the ink with color mixture in the second term is performed, and the achromatic component is calculated in the third term. Are added. Also, c in the second term
The multiplication term such as * m corrects the curvature of a specific hue in the xy chromaticity diagram, and furthermore, c * m / (c +
A multiplication / division term such as m) corrects rotation of a specific hue in the xy chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the method of the twenty-fifth aspect, in the matrix operation of the step (E) of the twenty-fourth aspect, a square root operation is executed instead of the multiplication / division.

According to the method of claim 26, in the matrix operation of step (E) of claim 24, the denominator of the multiplication / division is replaced by (r + c), (g + m) or (b + y). Calculations are performed.

According to the method of the twenty-seventh aspect, in step (B), the minimum value α is obtained as an achromatic component of the print data, and is separated from the color component of the print data in step (C). Depending on the step, matrix operators α, c, m, y, r,
g and b are obtained. Then, by the matrix operation of step (E), the calculation of the ideal ink without color mixture is performed in the first term, and the calculation of the achromatic component data by α, α * α is performed in the second term. Fine adjustment of the ink data is performed. Also, c in the second term
The multiplication term such as * m corrects the curvature of a specific hue in the xy chromaticity diagram, and furthermore, c * m / (c +
A multiplication / division term such as m) corrects rotation of a specific hue in the xy chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the method of the twenty-eighth aspect, in the matrix operation of the step (E) of the twenty-seventh aspect, a square root operation is executed instead of the multiplication / division.

According to the method of claim 29, in the matrix operation of step (E) of claim 27, the denominator of the multiplication / division is replaced by (r + c), (g + m) or (b + y). Calculations are performed.

According to the method of the thirtieth aspect, the image data R, G, B are the sensor data Cin, Min, Yin
And the print data C, M, and Y are the color separation data Rout, G
out and Bout, and the same color conversion is performed.

According to the method of the twenty-first aspect, in step (B), the minimum value α is obtained as an achromatic component of the print data, and is separated from the color component of the print data in step (C). D) determines the proportion of black ink used for achromatic printing, and these steps yield the matrix operators α, c, m, y, r, g, b of the matrix operation expression. Then, by the matrix operation in step (F), the first
The calculation of the ideal ink without color mixture in the term is performed, and the correction (modification) calculation for the ink with color mixture is performed in the second term, and the data of the achromatic component is added in the third term. The multiplication term such as c * m in the second term is xy
In the chromaticity diagram, a curve of a specific hue is corrected, and a multiplication / division term such as c * m / (c + m) is xy
This is to correct the rotation of a specific hue in the chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the method described in Item 32, in the matrix operation in Step (F) described in Item 31, an operation of a square root is executed instead of the multiplication / division.

According to a thirty-third aspect, in the matrix operation of the step (F) according to the thirty-first aspect, the denominator of the multiplication / division is replaced with (r + c), (g + m) or (b + y). Calculations are performed.

According to the method of claim 34, in step (B), the minimum value α is determined as an achromatic component of the print data, and is separated from the color component of the print data in step (C). D) determines the proportion of black ink used for achromatic printing, and these steps yield the matrix operators α, c, m, y, r, g, b of the matrix operation expression. Then, by the matrix operation in step (F), the first
In the term, the calculation of the ideal ink without color mixture is performed, and in the second term, the calculation of the data of the achromatic component by (α-K), (α-K) * (α-K) is performed. The data is fine-tuned. Also, c in the second term
The multiplication term such as * m corrects the curvature of a specific hue in the xy chromaticity diagram, and furthermore, c * m / (c +
A multiplication / division term such as m) corrects rotation of a specific hue in the xy chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the method described in Item 35, in the matrix operation in Step (F) described in Item 34, a square root operation is executed instead of the multiplication / division.

According to a thirty-sixth aspect, in the matrix operation of the step (F) according to the thirty-fourth aspect, the denominator of the multiplication / division is replaced with (r + c), (g + m) or (b + y). Calculations are performed.

According to the image processing apparatus of the present invention, the first-order component, the second-order component and the multiplication / division term make the first-order component,
The next component and the multiplication / division component can be respectively applied to the gradation characteristics.

According to the apparatus of the thirty-eighth aspect, the image data X and the modification amount a1.X. (X-a2) / (X + a3)
The data Y to be operated is obtained by the addition of .function., And the function operation according to claim 37 can be executed.

According to the apparatus of the thirty-ninth aspect, the image data X and the modification coefficient ｛1 + a1 · (X−a2) / (X + a
3) The operand data Y is obtained by multiplication of｝.
7 can be performed.

According to the apparatus described in Item 40, the image data X and the modification amounts a1, X, (X-a2), (X-a3)
/ (X + a4) is obtained to obtain the operated data Y,
The function operation according to claim 37 can be performed.

According to the apparatus of the twenty-first aspect, the image data X and the modification coefficient ｛1 + a1 · (X−a2) · (X−a
3) The data Y to be operated on is obtained by multiplication of / (X + a4)}, and the function operation according to claim 37 can be executed.

According to the apparatus of the present invention, the image data X and the correction amount ｛a1 · X · (X−a2) + a3 · X ·
The operation data Y is obtained by adding (X−a2) · (X−a4) / (X + a5)}, and the function operation according to claim 37 is executed.

According to the apparatus of claim 43, the image data X and the modification coefficient ｛1 + a1 · (X−a2) + a3 ·
The operation data Y is obtained by multiplying (X−a2) · (X−a4) / (X + a5)}, and the function operation according to claim 37 is executed.

According to the device of the forty-fourth aspect, the image data X and the modification amounts a1, X, (X-a2), (X-a3)
The data Y to be operated is obtained by subtraction of the above, and the function operation according to claim 37 is executed.

According to the device of the forty-fifth aspect, the image data X and the modification coefficient ｛1−a1 · (X−a2) · (X−a
3) The operand data Y is obtained by multiplication of｝.
The function operation described in 7 is executed.

According to the device of the forty-sixth aspect, the image data X and the modification amount X · (X−a3) · ｛a4 · (X−a
2) The data Y to be operated is obtained by subtracting + a5 · | X−a2 |｝, and the function operation according to claim 37 is executed.

According to the apparatus of claim 47, the image data X and the modification coefficient [1− (X−a3) · Ｘa4 · (X−
a2) + a5 · | X−a2 |｝] to obtain the operated data Y, and execute the function operation according to claim 37.

According to the device of the forty-eighth aspect, when image data X and X≤h, a1.X. (Xh). (X
-A3), when X> h, a2 · (X−h) · (X−a)
4) The data Y to be operated is obtained by subtracting the modification amount of (X-a5), and the function operation according to claim 37 is executed.

According to the device of the forty-ninth aspect, when the image data X and X ≦ h, a1 × X (X−h), X>
At the time of h, the operation data Y is obtained by subtracting the modified amount of a2 · (X−h) · (X−a3), and the function operation according to claim 37 is executed.

According to the image processing apparatus described in claim 50, claim 38, claim 39, claim 40, or claim 4
1, Claim 42, Claim 43, Claim 44, Claim 4
A plurality of gradation conversion characteristics can be realized by changing a constant or a numerical value of a threshold value inherent to the function formula of claim 5, claim 46, claim 47, claim 48, or claim 49.

According to the image processing apparatus of the twenty-first aspect, gradation conversion of an arbitrary characteristic can be performed by table conversion using a memory capacity corresponding to one characteristic, and a multiplier, a divider, and the like can be used. Faster conversion than when used. Note that the memory capacity is fixed, and every time the gradation characteristic is changed, a process of storing the data to be operated obtained in advance by the function operation of the present invention is required.

According to the image processing apparatus of the present invention, the function operation expression for gradation conversion can be calculated by an approximate value of logarithmic operation. Since the visibility characteristics of humans can be approximated by logarithmic characteristics, it is suitable, for example, for gradation processing of color separation data in a scanner device.

According to the apparatus of claim 53, in the means (B), the minimum value α is determined as an achromatic component of the print data, and separated from the color component of the print data by the means (C). By means, a matrix operator α, c, m, y, r, g, b of a matrix operation expression is obtained. By the matrix operation of the means (E), the operation of the ideal ink without color mixture in the first term is performed, and the correction (modification) operation for the ink with color mixture in the second term is performed, and the achromatic component is calculated in the third term. Are added. The multiplication term such as c * m in the second term corrects the curvature of a specific hue in the xy chromaticity diagram, and the multiplication / division term such as c * m / (c + m) is xy This is to correct the rotation of a specific hue in the chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the apparatus of claim 54, in the matrix operation of the means (E) of claim 53,
Instead of multiplication and division, a square root operation is executed.

According to the apparatus of claim 55, in the matrix operation of the means (E) of claim 53,
The denominator of multiplication / division is (r + c), (g + m) or (b +
The calculation is executed by the replacement of y).

According to the apparatus of claim 56, in the means (B), the minimum value α is obtained as an achromatic component of the print data, and separated from the color component of the print data by the means (C). By means, a matrix operator α, c, m, y, r, g, b of a matrix operation expression is obtained. By the matrix operation of the means (E), the operation of the ideal ink without color mixture is performed in the first term, and the calculation of the achromatic component data by α, α * α is performed in the second term. Fine adjustment of the ink data is performed. The multiplication term such as c * m in the second term corrects the curvature of a specific hue in the xy chromaticity diagram, and the multiplication / division term such as c * m / (c + m) is xy This is to correct the rotation of a specific hue in the chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the apparatus of claim 57, in the matrix operation of the means (E) of claim 56,
Instead of multiplication and division, a square root operation is executed.

According to the apparatus of claim 58, in the matrix operation of the means (E) of claim 56,
The denominator of multiplication / division is (r + c), (g + m) or (b +
The calculation is executed by the replacement of y).

According to the device of the fifty-ninth aspect, the image data R, G, B are converted into the sensor data Cin, Min, Yin.
The print data C, M, and Y are converted to the color separation data Rout, G
out and Bout, respectively.
Color separation data can be obtained from sensor data using filters for C, M, and Y.

According to the apparatus of the present invention, in the means (B), the minimum value α is obtained as an achromatic component of the print data, and is separated from the color component of the print data by the means (C). D) determines the proportion of black ink used for achromatic printing, and by these means, the matrix operators α, c,
m, y, r, g, b are obtained. By means of the matrix operation of the means (F), the operation of the ideal ink without color mixture in the first term is performed, and the correction (modification) operation on the ink with color mixture in the second term is performed. Are added. The multiplication term such as c * m in the second term corrects the curvature of a specific hue in the xy chromaticity diagram.
A multiplication / division term such as (c + m) corrects rotation of a specific hue in the xy chromaticity diagram. Thereby, RG
Achromatic data and six hue data are generated from the B image data, and each hue can be independently corrected (modified).

According to the apparatus of claim 61, in the matrix operation of the means (F) according to claim 60,
Instead of multiplication and division, a square root operation is executed.

According to the apparatus of claim 62, in the matrix operation of the means (F) according to claim 60,
The denominator of multiplication / division is (r + c), (g + m) or (b +
The calculation is executed by the replacement of y).

According to the apparatus of claim 63, in the means (B), the minimum value α is obtained as an achromatic component of the print data, and is separated from the color component of the print data by the means (C). D) determines the proportion of black ink used for achromatic printing, and by these means, the matrix operators α, c,
m, y, r, g, b are obtained. Then, by the matrix operation of the means (F), the operation of the ideal ink without color mixture in the first term is changed to (α−K),
The calculation of the achromatic component data by (α-K) * (α-K) is performed, and the fine adjustment of the achromatic component ink data is performed. The multiplication term such as c * m in the second term corrects the curvature of a specific hue in the xy chromaticity diagram, and the multiplication / division term such as c * m / (c + m) is xy This is to correct the rotation of a specific hue in the chromaticity diagram. Thereby, achromatic color data and six hue data are generated from the RGB image data, and each hue can be independently corrected (corrected).

According to the apparatus of claim 64, in the matrix operation of the means (F) of claim 63,
Instead of multiplication and division, a square root operation is executed.

According to the apparatus of claim 65, in the matrix operation of the means (F) of claim 63,
The denominator of multiplication / division is (r + c), (g + m) or (b +
The calculation is executed by the replacement of y).

According to the image processing apparatus of the present invention, a general-purpose color conversion function can be realized by preparing various color conversion modes and selectively using a plurality of functions.

According to the image processing apparatus of claim 67, a general-purpose color conversion function can be realized with a small amount of arithmetic means using a memory capacity corresponding to one characteristic.

According to the image processing apparatus of the present invention, a specific processing characteristic is selected from a plurality of processing characteristics based on the characteristics of the input device, the characteristics of the output device, and the overall characteristics to be realized. Image processing can be performed on the image data. According to the image processing apparatus of claim 69, the first
It is possible to select a specific processing characteristic from among a plurality of processing characteristics according to the characteristics of the device or the characteristics with the input image data, the characteristics of the second device, and the overall characteristics to be realized, and perform optimal image processing. it can. Further, since the input image data X is directly converted into the converted data Y, an error due to the conversion can be reduced. According to the image processing apparatus of claim 70, when the first device is a display device or an image reading device, the first
It is possible to select a specific processing characteristic from among a plurality of processing characteristics according to the characteristics of the device or the characteristics with the input image data, the characteristics of the second device, and the overall characteristics to be realized, and perform optimal image processing. it can.

[0171]

[Embodiment 1] FIG. 1 is a block diagram showing a configuration of a gradation processing apparatus according to one embodiment of the present invention. In the figure, 1 is a constant generator, 2 is a first multiplier, 3 is a second multiplier, 4 is a divider, 5 is a first subtractor, 6 is a first adder, 7 is a second adder. Is an adder. Note that the constant generator 1
It includes means and functions for freely changing the constants generated in response to external inputs. In the following description,
The constants a1, a2, etc. are simply referred to as a1, a2, etc.

Next, the operation of the gradation processing apparatus of FIG. 1 will be described. The input image data X is input to a first multiplier 2, a first subtractor 5, and a first adder 6. The constant generator 1 generates a1, a2, and a3, and supplies them to the first multiplier 2, the first subtractor 5, and the first adder 6, respectively. The first multiplier 2 outputs the product a1 · X. First
Subtractor 5 outputs the difference (X-a2). The first adder 6 outputs the sum (X + a3). Second multiplier 3
Outputs the product a1.X. (X-a2). Divider 4
Outputs the quotient a1.X. (X-a2) / (X + a3).

The second adder 7 outputs the operation data Y1 represented by the equation (1). Y1 = X + a1 · X · (X−a2) / (X + a3) (1)

The right-hand side of the equation (1) is the linear term of the first term and the second term.
Term. The correction term relates to the amount of modification from the linear term, and the maximum value is determined by a1, and the input value at which the amount of modification is maximum is determined by the constant a3. The amount of modification is X = 0, X =
It becomes zero at a2.

FIG. 2 is a diagram showing input / output characteristics of the gradation processing apparatus of FIG. In the figure, the horizontal axis indicates the input density value of the image data X, and the vertical axis indicates the output density value of the operated data Y1, and their correspondence is shown as an input / output conversion curve. Here, a2 = Xmax (the maximum value of the image data X), and FIG.
FIG. 6B shows the case where a3 <−a2. The solid line is a1 <0, the broken line is a1> 0, and the straight line is a1 = 0.

FIG. 3 is a diagram showing another input / output characteristic of the gradation processing apparatus of FIG. This is an example of input / output characteristics expressed by a function operation of Y1 = Y1max · {(X / Xmax) to the γ-th power)} where Y1max is the maximum value of the operated data Y1, and what is called γ (gamma) The characteristic is a function approximation. In the figure, a2 = Xmax, and FIG.
In the case of 2.2, FIG. 6B shows the case of γ = 2.2.

Here, the solid line represents the approximation characteristic by the equation (1),
The dashed line is the theoretical value. When the image data X is 8 bits, a
2 = 255, and the characteristic of FIG.
7, a3 = 30, and the characteristic of FIG.
8, a3 = -1895 is adopted. Note that gamma (γ) and “gradation” are used as synonyms.

FIG. 4 is a diagram showing still another input / output characteristic of the gradation processing apparatus of FIG. This gradation processing is an example in which another gamma characteristic is approximated, where a2 = Xmax, FIG. 6A shows the case where γ = 1 / 3.0, and FIG.
3.0. The solid line is the approximate characteristic according to the equation (1), and the broken line is the theoretical value. Each approximation characteristic is a2 =
255, (A) expresses a1 = −0.67, a3 = 18,
(B) adopts numerical values of a1 = −2.5 and a3 = −553.

Here, as typical gamma characteristics, γ = 1 / 2.2 and γ used for gamma correction and inverse gamma correction
= 2.2, and γ = 1/3 and γ = 3, which are used for the conversion of the L ^* a ^* b ^* color system to the brightness characteristic L ^* and the inverse conversion, have been described. However, the expression (1) can also approximate an arbitrary characteristic for gamma characteristics other than those described above by appropriately using the numerical values of a1, a2, and a3.

The equation (1) can be transformed as follows: Y1 = XＸ {1 + a1 ・ (X-a2) / (X + a3)} (2)

This is because the image data X and the modification coefficient ｛1 + a
1 · (X−a2) / (X + a3)} indicates that the data is the operated data Y1. The configuration for realizing the function operation of Expression (2) can be realized by modifying the gradation processing device of FIG.

Embodiment 2 FIG. FIG. 5 is a block diagram showing a configuration of a gradation processing apparatus according to another embodiment of the present invention. In the second embodiment, 8 is a third multiplier and 9 is a second subtractor. The other configuration blocks are the same as those of the gradation processing device of the first embodiment (FIG. 1).

Next, the operation of the gradation processing apparatus shown in FIG. 5 will be described. The input image data X is supplied to a first multiplier 2, a first subtractor 5, a second subtractor 9, and a first adder 6. The constant generator 1 generates a1, a2, a3, a4 and supplies them to the first multiplier 2, the first subtractor 5, the second subtractor 9, and the first adder 6, respectively. The first multiplier 2 outputs the product a1 · X. The first subtractor 5 and the second
Subtractor 9 outputs the difference (X-a2) and (X-a3), respectively. The first adder 6 outputs the sum (X + a4). The second multiplier 3 and the third multiplier 8 each have a product a1 ·
X · (X−a2) and a1 · X · (X−a2) · (X−a
3) is output. The divider 4 calculates the quotient a1 · X · (X−a
2) Output (X-a3) / (X + a4).

The second adder 7 outputs the operation data Y2 expressed by the following equation (3). Y2 = X + a1 · X · (X−a2) · (X−a3) / (X + a4) (3)

The right side of the equation (3) includes a linear term and a correction term. The correction term is related to the amount of modification from the linear term. A4 determines the input value at which the amount of modification is maximum, and a1 is the maximum value
Decides. The modification amounts are X = 0, X = a2, X = a3
And the sign is reversed before and after a2.

FIG. 6 is a diagram showing input / output characteristics of the gradation processing apparatus of FIG. This input / output characteristic indicates that the relationship between the image data X and the operated data Y2 is an S-shaped characteristic. In FIG. 6, a3 = Xmax, and FIG.
Shows a case where a4> 0, and FIG. 13B shows a case where a4 <−a3. The solid line is a1> 0, the broken line is a1 <0,
The straight line is the case where a1 = 0.

FIG. 7 is a diagram showing another input / output characteristic of the gradation processing apparatus of FIG. FIG. 8 is a diagram showing still another input / output characteristic of the gradation processing device of FIG. Each of these input / output characteristics shows a non-S-shaped processing characteristic.

In FIG. 7, (A) shows a2 = a3 =
In the case of Xmax, a4> 0, FIG.
Xmax, where a4 <−a3. In FIG.
FIG. 4A shows a case where a2 = 0, a3 = Xmax, and a4> 0, and FIG. 4B shows a2 = 0, a3 = Xmax, and a4 <−.
This is the case of a3. The solid line is a1> 0, and the broken line is a1
<0, the straight line is the case where a1 = 0.

As described above, complex input / output characteristics can be realized by the function operation of equation (3).

Equation (3) can be transformed as follows: Y2 = XＸ {1 + a1 ・ (X−a2) ・ (X−a3) / (X + a4)} (4) The image data X and the modification coefficient {1 + a1ａ (X
−a2) · (X−a3) / (X + a4)} indicates that the converted data Y2 is obtained. The configuration for realizing Expression (4) can be realized by modifying this gradation processing device (FIG. 5).

Embodiment 3 FIG. FIG. 9 is a block diagram showing a configuration of a gradation processing apparatus according to Embodiment 3 of the present invention. The third embodiment is configured to cyclically perform the function operation of the equation (1). Here, reference numeral 10 denotes a DFF (D-type flip-flop circuit) for temporarily storing operation data;
And 13 are first, second and third selectors, respectively. The other blocks are the same as those described above, and are denoted by the same reference numerals and will not be described.

Next, the operation of the gradation processing apparatus shown in FIG. 9 will be described. The input image data X is supplied to a first adder 6, a second adder 7, and a second selector 12, respectively.
The constant generator 1 generates a1, -a2, and a3, and outputs a1 to the third selector 13, and -a2, a3 to the first selector 11
To supply.

First, the second selector 12 outputs image data X, and the third selector 13 outputs a1. The first multiplier 2 outputs the product a1 · X. The DFF 10 temporarily stores this product.

Next, the second selector 12 selects the DFF 10
And outputs the product a1 · X output by. The first adder 6
The sum (X-a2) of -a2 output from the first selector 11 and the image data X is output. The third selector 13 outputs the sum. The first multiplier 2 calculates the product a1 · X · (X−a
2), and the DFF 10 temporarily stores the product.

Further, the first adder 6 outputs the sum (X + a3) of a3 output from the first selector 11 and image data X. The divider 4 calculates the quotient a1 · X · (X−a2) / (X + a) of the product a1 · X · (X−a2) and the sum (X + a3).
3) is output. The second adder 7 calculates the sum of the image data X and the quotient by using the operand data Y1 represented by Expression (1).
Output as

The hardware scale of the gradation processing device of FIG. 9 can be smaller than that of the gradation processing device of the first embodiment (FIG. 1).
For example, the multiplier has 500 gates, the divider has 700 gates, the adder has 50 gates, the selector has 20 gates, and the DFF has
Is 40 gates, 1850 in total in the first embodiment, and 1400 in total in the third embodiment. Therefore,
The gradation processing device of the first embodiment (FIG. 1) is suitable for high-speed processing, and the gradation processing device of the third embodiment is suitable for cost reduction.

The gradation processing apparatus according to the third embodiment can be modified such that the first adder 6 and the second adder 7 are integrated. The constant generator 1 can be easily realized by a microcontroller (microcomputer) or hardware logic.

Further, in the gradation processing apparatus of the third embodiment, the configuration for outputting the operated data Y1 expressed by the equation (1) has been described. However, the configuration corresponds to the equations (2), (3) and (4). With respect to such a configuration, it is possible to design the same concept.

Embodiment 4 FIG. FIG. 10 shows Embodiment 4 of the present invention.
FIG. 4 is an input / output characteristic diagram of the gradation processing device showing the above. The input / output characteristics are such that the input data Y3
Is expressed by the following arithmetic expression (5). Y3 = X + a1.X. (X-a2) + a3.X. (X-a2). (X-a4) / (X + a5) (5)

Hereinafter, the first, second, and third terms will be referred to as Y3
1, Y32, Y33, and the operated data Y3 = Y3 =
The description will be made as Y31 + Y32 + Y33.

In the figure, Y31 is the first term on the right side of the equation (5), Y32 is the second term, Y33 is the third term, and Y3 is the third term.
Shows an example of the total input / output characteristics of Expression (5). When the image data X is 8 bits, a2 = 255, and here, a1 =
-0.003, a3 = -0.01, a4 = 128, a5
= 50 is adopted.

Here, the right side of equation (5) comprises a linear term Y31 and two correction terms Y32 and Y33, and the sum of the three terms determines the gradation characteristic. The correction term Y32 represents the secondary component and the correction term Y3
3 can independently modify the (third-order / first-order) component, and the sum (Y
32 + Y33) is the amount of modification from the linear term. Thus, equation (5) can realize more complicated input / output characteristics.

The gradation processing by the equation (5) can be performed by adding a quadratic term calculating means to the gradation processing apparatus of the second embodiment (FIG. 5) or by using the gradation processing method of the thirteenth embodiment (described later). FIG.
This can be achieved by adding a quadratic term calculation step in 4).

Further, the above equation (5) can be modified as follows: Y3 = X ｛{1 + a1 ・ (X-a2) + a3 ・ (X-a2) ・ (X-a4) / (X + a5)｝ (6) . The function operation of this equation (6) is also performed by the equation (5).
Can be realized by modifying the gradation processing device that realizes the function operation of

Embodiment 5 FIG. FIG. 11 shows Embodiment 5 of the present invention.
FIG. 3 is a block diagram illustrating a configuration of a gradation conversion device. In the figure, 14 is a first preprocessor, 1 is a constant generator, 2
Is a first multiplier, 3 is a second multiplier, 15 is a third multiplier, and 5 is a subtractor.

Next, the operation of the gradation processing device will be described. The image data X is transmitted to the first pre-processor 14 and the second
Are input to the multiplier 3 and the subtractor 5. The constant generator 1 is
Generate constants a1, a2 and a3 and supply them to other blocks as shown in the figure. The first preprocessor 14 calculates the difference (Xa
2), (X-a3) is output. The first multiplier 2 outputs the product (X-a2) · (X-a3). The second multiplier 3 outputs the product a1 · X. The third multiplier 15 outputs the product a1.X. (X-a2). (X-a3).

The subtractor 5 outputs the converted data Y4 by the function operation of the equation (7). Y4 = X-a1.X. (X-a2). (X-a3) (7)

The right side of the equation (7) is composed of the first linear term and the second correction term. The correction term relates to the amount of modification from the linear term, and its maximum value is determined by the constant a1. This modification amount becomes zero when X = 0, X = a2, and X = a3, and the sign is reversed before and after that.

FIG. 12 is a diagram showing input / output characteristics of the gradation conversion device of FIG. This figure shows the input / output characteristics of the image data X and the converted data Y4, which are S-shaped characteristics. In the figure, the solid line is a1> 0, the broken line is a1 <0,
The straight line is the case where a1 = 0.

FIG. 13 is a diagram showing another input / output characteristic of the gradation converter of FIG. This shows a non-S-shaped conversion characteristic. FIG. 7A shows a case where a2 = a3 = the maximum value of image data, and FIG. 7B shows a case where a2 = 0 and a3 = a3 = image data. This is the case with the maximum value. Here, the solid line is a1>
0, the broken line is a1 <0, and the straight line is a1 = 0. By substituting the actual image data (R, G, B) for X in equation (7), the data to be converted (R1, G1, B1) can be obtained.

The above equation (7) can be decomposed as follows: Y4 = X ＝ {1−a1 · (X−a2) · (X−a3)} (8) This equation (8) is obtained by modifying the correction coefficient ｛1−a1 ·
This shows that the converted data Y4 is obtained by multiplying the image data X by (X−a2) · (X−a3)}, and this embodiment can be easily designed by a circuit designer.

Embodiment 6 FIG. FIG. 14 shows Embodiment 6 of the present invention.
FIG. 3 is a block diagram illustrating a configuration of a gradation conversion device. In the figure, reference numeral 16 denotes a second preprocessor, and 17 denotes a fourth multiplier. The other building blocks are the same as those described above.

The operation of the gradation processing device will be described. The image data X is input to the second pre-processor 16, the first multiplier 2 and the subtracter 5. The constant generator 1 has a constant a
2, a3, a4 and a5 are generated and supplied to each block as shown. The second preprocessor 16 is obtained by adding an absolute value circuit to the first preprocessor 14, and calculates a difference (X−a3),
(X-a2) and the absolute value | X-a2 | The first multiplier 2 outputs the product X · (X−a3). The second multiplier 3 outputs the product a4 · (X−a2). Third multiplier 15 outputs product a5 · | X−a2 |. The adder 103 outputs a4 · (X−a2) + a5 · | X−a2 |. The fourth multiplier 17 calculates the product X · (X−a3) ·
{A4 · (X−a2) + a5 · | X−a2 |} is output.

The subtractor 5 outputs the converted data Y5 by the function operation of the following equation (9). Y5 = XX · (X−a3) · {a4 · (X−a2) + a5 · | X−a2 |} (9)

FIG. 15 is a diagram showing the input / output characteristics of the gradation converter of FIG. The right side of the operand data Y5 (Equation (9)) includes a linear term and a correction term, and X ≦ a2
, Y5 = X− (a4-a5) · X · (X−a2) · (X−
a3) When X> a2, Y5 = X− (a4 + a5) · X · (X−a2) · (X−
a3)

Therefore, the relationship between the image data X and the converted data Y5 has an S-shaped conversion characteristic as shown in FIG. In the figure, the ratio of the modification amount at X <a2 and the modification amount at X> a2 is (a4-a5) :( a4 + a5), and the conversion characteristic can be changed by the ratio of a4 and a5.

Expression (9) can be decomposed into image data and modification coefficients as follows. Y5 = X. [1- (X-a3). {A4. (X-a2) + a5. | X-a2 |}] (10)

This formula can also be easily realized by slightly modifying the gradation processing device of the sixth embodiment (FIG. 14).

Embodiment 7 FIG. FIG. 16 shows Embodiment 7 of the present invention.
FIG. 3 is a block diagram illustrating a configuration of a gradation conversion device. In the figure, 18 is a threshold generator, 19 is a third pre-processor, 11, 12 and 13 are first, second and third selectors, respectively, and the other blocks are described above. It is the same as the one.

Next, the operation of the gradation converter of FIG. 16 will be described. The image data X is input to the third preprocessor 19, the third selector 13, and the subtractor 5. The threshold generator 18 and the constant generator 1 provide a threshold h and variables a1, a
2, a3, a4, a5, and the threshold value h and the variable a
3, a4, and a5 are stored in the third preprocessor 19 as variables a1, a
2 to the second selector 12. Third preprocessor 19
Are the differences (Xh), (Xa3), (Xa4), (X
-A5) and the comparison data SL are output. Comparison data SL
Is the result of comparing the magnitudes of X and h.
When X> h, logic H is output. The first selector 1 outputs SL =
L represents Xh and Xa3, and SL = H represents Xa4 and Xa.
5 is output. The first multiplier 2 calculates the product (X−h) · (X
-A3) or (X-a4) · (X-a5) is output.
The second selector 12 selects a1 when SL = L and a when SL = H
2 is output. The third selector 13 outputs X when SL = L,
Xh is output when SL = H. The second multiplier 3 calculates the product a
1 × or a2 × (X−h) is output. The third multiplier 15 outputs the product a1 · X · (X−h) · (X−a3) or a2 · (X−h) · (X−a4) · (X−a5).

The subtractor 5 calculates the following equations (11) and (12)
The converted data Y6 is output by the function operation of. X ≦ h
, Y6 = X-a1.X. (X-h). (X-a3) (11) When X> h, Y6 = X-a2. (X-h). (X-a4). (X-a5) ... (12)

The equations (11) and (12) also include a linear term and a correction term, and the relationship between the image data X and the converted data Y6 is an S-shaped input / output characteristic. Equations (11), (1
In 2), the modification amount when X ≦ h and the modification amount when X> h are determined by a1 and a2, respectively.

FIG. 17 is a diagram showing input / output characteristics of the gradation conversion device of FIG. The feature of these equations (11) and (12) is that, as shown in FIG. 17, even if h, a1, a2, and a4 are fixed, the S-shaped shape can be freely changed by the value of a3 or a5. There is a point that can be. FIG. 4A shows a3 = 0,
In the case of a5 = a4, (B) is the case of a3 = a4, a5 = 0, and (C) is the case of a3 = a5 = h.

Embodiment 8 FIG. FIG. 18 shows Embodiment 8 of the present invention.
FIG. 3 is a block diagram illustrating a configuration of a gradation conversion device. The gradation processing apparatus according to the eighth embodiment has the simplest block configuration among the embodiments described so far. Each block is the same as described above.

Next, the operation of the gradation converter shown in FIG. 18 will be described. The image data X is input to the third preprocessor 19, the second selector 12, and the subtractor 5. The threshold generator 18 and the constant generator 1 provide a threshold h and a constant a1,
a2 and a3 are generated, and the threshold value h and the constant a3 are supplied to the third preprocessor 19, and the constants a1 and a2 are supplied to the third selector 13. The third preprocessor 19 outputs the differences (Xh), (Xa3) and the comparison data SL. This comparison data S
L is the same as in the embodiment of FIG. Second selector 12
Outputs X when SL = L and X-a3 when SL = H.
The first multiplier 2 calculates the product X · (X−h) or (X−h) ·
(X-a3) is output. The third selector 13 selects SL =
A1 is output with L and a2 is output with SL = H. The second multiplier 3 calculates the product a1 · X · (X−h) or a2 · (X−h)
Output (X-a3).

The subtractor 5 calculates the following equations (13) and (14)
The converted data Y7 is output by the function operation of. X ≦ h
When Y7 = X-a1.X. (X-h) (13) When X> h, Y7 = X-a2. (X-h). (X-a3) ... (14)

FIG. 19 is a diagram showing input / output characteristics of the gradation conversion device of FIG. The feature of these equations (13) and (14) is that they have an S-shaped conversion characteristic as shown in FIG. As a result, a reduction in the circuit scale of the gradation conversion device and an improvement in the processing speed can be expected.

Embodiment 9 FIG. FIG. 20 shows Embodiment 9 of the present invention.
FIG. 3 is a block diagram illustrating a configuration of a gradation conversion device. According to the configuration of the gradation conversion device, the function operation expression (7) in the fifth embodiment can be realized by one multiplier.
In the figure, reference numeral 14 denotes a DFF for temporarily storing data. Other blocks are the same as those described so far, and are denoted by the same reference numerals and will not be described.

Next, the operation of the gradation converter of FIG. 20 will be described. The image data X is input to the subtracter 5. The constant generator 1 generates constants a1, a2, a3,
The constant a1 is assigned to the second selector 12, and the constants a2 and a3 are assigned to the first selector.
Is supplied to the selector 11. Storage data P of DFF10
Sets the initial state of P = 0. Under this condition, the subtractor 5 inputs the image data X and the storage data P selected by the first selector 11, and outputs the difference B = X−P = X.
The second selector 12 selects a1 and selects the selected data A =
a1 is output. The first multiplier 2 outputs the product a1 · X. The DFF 10 temporarily stores this product as P.

Next, the first selector 11 outputs a2, and the second selector 12 outputs stored data P. At this time, A = P. Since the subtractor 5 outputs B = X−a2, the product of the first multiplier 2 is a1 × X (X−a
2). This is also temporarily stored in the DFF 10.

Next, the first selector 11 outputs a3, and the second selector 12 outputs stored data P. The output of the subtracter 5 is B = X−a3, and the product is a1 · X ·
(Xa2) · (Xa3). This is also DFF10
To be stored temporarily. The stored data P is stored in the first selector 1
1 and the subtraction data B of the subtractor 5 is B = X-a1.X. (X-a2). (X-a3). This equation becomes equation (7) when B is replaced with Y4.

In general, the circuit scale of the image multiplier is several hundred gates, but the device of the fifth embodiment (FIG. 11) has about 2K gates, whereas the device of the ninth embodiment has about 1K gates, which is half. become. However, the circuit configuration of FIG. 20 is based on the cyclic operation method, and the processing speed is slow.

In the ninth embodiment, the configuration for realizing the equation (7) has been described. However, the equations (9), (11),
(12) and equations (13) and (14),
Circuits of the same concept can be easily designed.

Embodiment 10 FIG. FIG. 21 is a block diagram showing a configuration of a gradation processing apparatus according to Embodiment 10 of the present invention. The configuration of this gradation conversion apparatus is characterized in that gradation processing can be performed at an extremely high speed. Here, 24 is a fixed capacity memory, 25 is a bidirectional buffer, 26 is an address generator, 27 is a conversion data generator, and 28 is a controller. Others are the same as those described so far, and are omitted.

Next, the operation of the gradation processing apparatus shown in FIG. 21 will be described. The address generator 26 generates data 0, and this data is output from the first selector 11 and supplied to the address terminal of the memory 24. The converted data generator 17 generates converted data Y corresponding to the image data X = 0, and supplies the converted data Y to the data terminal of the memory 24 through the bidirectional buffer 25. In this state, the controller 28 outputs a write pulse to the memory 24, and writes the converted data Y to the address 0. Similarly, the conversion data at the address 1 is written in the memory 24. The same processing is performed at address 25
The execution is sequentially performed up to the address 5, and the storage of the conversion data corresponding to the 8-bit input is completed in the memory 24.

Next, the first selector 11 sets the image data X
The bidirectional buffer 25 is set by the controller 28 to a mode for outputting the converted data Y. In this state, if image data X is sequentially input, converted data Y is obtained by table conversion. This memory 24 can use an ultra-high-speed SRAM, and can perform processing at 50 MHz or more. The processing speed of the apparatus of the first embodiment (FIG. 1) is limited to about 30 MHz in a general-purpose LSI manufacturing process.

Here, the conversion data generator 27 generates the data to be converted using the arithmetic expressions (1) and (2) or the expressions (3) and (4), but high-speed processing is not required. Therefore, the circuit configuration of the third embodiment (FIG. 9) can be adopted. Further, the address generator 26, the conversion data generator 27, and the controller 28 can realize the same function by a microcomputer or the like by using software processing.

Embodiment 11 FIG. FIG. 22 is a block diagram showing a configuration of a gradation conversion apparatus according to Embodiment 11 of the present invention. The configuration of this gradation conversion apparatus is characterized in that gradation processing can be executed at an extremely high speed using a fixed-capacity memory. Here, 24 is a memory, 25 is a bidirectional buffer, 26 is an address generator, 27 is a conversion data generator, and 28 is a controller. Other blocks are the same as those described so far, and will not be described.

Next, the operation of the gradation processing apparatus shown in FIG. 22 will be described. The address generator 26 first generates data 0. This data is supplied to the second selectors 12a to 12a.
and is supplied to the address terminals of the memories 24a to 24c. The conversion data generator 27 generates conversion data corresponding to the image data X = 0, and outputs the conversion data to the memory 24 through the bidirectional buffers 25a to 25c.
a to 24c are supplied to the data terminals. In this state, the controller 28 outputs the write pulse to each of the memories 24a to 24a.
4c, and stores the converted data at address 0 in memory 2
Write to 4a to 24c. Similarly, the conversion data at the address 1 is written into the memories 24a to 24c. Such processing is sequentially performed up to the address 255, and the storage of the conversion data corresponding to the 8-bit input is completed in the memories 24a to 24c.

Thereafter, the second selectors 12a to 12c are set to the mode for inputting image data (R, G, B), and the bidirectional buffers 25a to 25c are set to the data to be converted (R1, G
1, B1) is set by the controller 28. In this state, if image data is sequentially input,
Data to be converted (R1, G1, B1) is obtained by table conversion. The memories 24a to 24c are high-speed SRAMs, and can perform real-time conversion processing up to several tens of MHz.

Here, the conversion data generator 27 generates the data to be converted using the arithmetic expressions (7) to (12). However, since high-speed processing is not required, the circuit configuration of the ninth embodiment (see FIG. 20) can be adopted. Further, the address generator 26, the conversion data generator 27, and the controller 28 can realize the same function by a microcomputer or the like by using software processing.

When the apparatus of the fifth embodiment (FIG. 11) is applied to RGB image data, the number of gates is about 6,000. On the other hand, the 256B SRAM is equivalent to 1200 gates. In the device of the eleventh embodiment, the circuit configuration shown in FIG. 20 is used, and about 5000 gates are used, and a CPU prepared for realizing another function is used. By doing so, the circuit can be compressed to about 4000 gates. Further, by changing the constant of the conversion data generator 27, an arbitrary conversion characteristic can be realized.

Embodiment 12 FIG. FIG. 23 is a flowchart showing a gradation processing method according to Embodiment 12 of the present invention.
Referring to FIG. 23, as an example of the gradation conversion program, a procedure for performing the function operation of Expression (1) by software will be described.

In the step (23a) (hereinafter, the step is omitted), the total number N of pixels to be processed is input.
In (23b), a1, a2, and a3 are stored (hereinafter abbreviated as storage) in respective registers (hereinafter, registers are omitted) R1, R2, and R3. In (23c), the image data X is input and stored in R0. In (23d), R
The difference of 0-R2 is stored in R4. In (23e), R0
The sum of + R3 is stored in R5. In (23f), R0 *
The product of R1 is stored in R6. (23g), R4 * R
The product of 6 is stored in R7. In (23h), R7 / R5
Is stored in R8. In (23i), the sum of R0 + R8 is stored in R9. At (23j), the contents of R9 are output as the operated data Y1. In (23k), N-
1 is performed. In (231), the continuation of the process is determined. When continuing, the process jumps to (23c), and when not continuing, the process ends. Note that (23a) includes a function of freely changing the numerical values of a1, a2, and a3 by an external input.

Embodiment 13 FIG. FIG. 24 is a flowchart showing a gradation processing method according to Embodiment 13 of the present invention.
Referring to FIG. 24, as an example of the gradation conversion program, a procedure for performing the function operation of Expression (3) by software will be described.

In step (24a), the total number N of pixels to be processed is input. In (24b), a1, a2, a3, and a4 are stored in R1, R2, R3, and R4, respectively. In (24c), the image data X is input and stored in R0. (24
In d), the difference of R0-R2 is stored in R5, the difference of R0-R3 is stored in R6, and the sum of R0 + R4 is stored in R7. (24
In e), the product of R0 * R1 is stored in R8 and the product of R5 * R6 is stored in R9.

In (24f), the product of R8 * R9 is calculated as R10
To memorize. (24g), the quotient of R10 / R7 is R1
1 is stored. In (24h), the sum of R0 + R11 is R
12 is stored. In (24i), the contents of R12 are output as data Y to be operated on. At (24j), processing of N-1 is performed. At (24k), the continuation of the process is determined. When the continuation is performed, the process jumps to (24c). When the process is not continued, the process is terminated. Note that (24a) includes a function of freely changing the numerical values of a1, a2, a3, and a4 by an external input.

The embodiments 12 and 13 shown in FIGS. 23 and 24 are based on the arithmetic expression (1) or (3), respectively. The flowchart of FIG.
It can be easily realized by deforming 2 and 13.

Embodiment 14 FIG. FIG. 25 is a flowchart showing a gradation processing method according to Embodiment 14 of the present invention.
Referring to FIG. 25, as an example of the gradation conversion program, a procedure for performing the function operation of Expression (7) by software will be described.

In the step (25a) (hereinafter, the step is omitted), the total number N of pixels to be processed is input.
In (25b), the constants a1, a2, and a3 are temporarily stored in registers R1, R2, and R3, respectively (hereinafter, abbreviated as storage). In (25c), the image data X is input and stored in a register R0 (hereinafter, register is omitted). (25
In d), the processing result of R0-R2 is stored in R4.
In (25e), the processing result of R0-R3 is stored in R5.

In (25f), R4 and R5 are multiplied (hereinafter, indicated by *), and the product is stored in R6. In (25g), the product of R0 * R1 is stored in R7. In (25h), the product of R6 * R7 is stored in R8. In (25i), the product of R0-R8 is stored in R9. In (25j), the contents of R9 are output as converted data Y4.
At (25k), processing of N-1 is performed. In (25m), the continuation of the process is determined. When continuing, the process jumps to (25c), and when not continuing, the process ends.

Embodiment 15 FIG. FIG. 26 is a flowchart showing a gradation processing method according to Embodiment 15 of the present invention.
Referring to FIG. 26, as an example of the gradation conversion program, a procedure for performing the function operation of Expression (9) by software will be described.

In step (26a), the total number N of pixels to be processed is input. In (26b), constants a2 to a5 are stored in R1, to R4, respectively. In (26c), the image data X is input and stored in R0. (26d)
The difference between R0-R1 is R5, the absolute value of R5 is R6, and R0
-Store the difference of R2 in R7. In (26e), the product of R3 * R5, R4 * R6 and R0 * R7 is R
8, R9 and R10.

In (26f), the sum of R8 + R9 is calculated as R11
To memorize. (26g), the product of R10 * R11 is R
12 is stored. In (26h), the difference between R0 and R12 is stored in R13. In (26i), R13 is output as converted data Y5. At (26j), processing of N-1 is performed. At (26k), continuation of the process is determined. When continuing, the process jumps to (26c), and when not continuing, the process ends.

Embodiment 16 FIG. FIG. 27 is a flowchart showing a gradation processing method according to Embodiment 16 of the present invention.
Referring to FIG. 27, as an example of the gradation conversion program, a procedure for performing the function calculation of equations (11) and (12) by software will be described.

In (27a), the threshold value h and the constants a1,
And a5 are stored in R1 to R6. (27b)
Then, the image data X is input and stored in R0. (27
In c), the magnitudes of R0 and R1 are compared, and when R0> R1, the process jumps to (27f). In (27d), R0
-Store the difference between R1 and R0-R4 in R7 and R8. (2
7e), the product of R0 * R2 and R7 * R8 is calculated as R10
And stored in R11.

In (27f), R0-R1 and R0-R5
And the difference between R0-R6 is stored in R7, R8 and R9, respectively.
(27g), the product of R3 * R7 and R8 * R9 is R10
And stored in R11. In (27h), R10 * R11
Is stored in R12. In (27i), R0-R1
The difference of 2 is stored in R13. In (27j), R13 is output as converted data Y6. At (27k), continuation of the process is determined. When continuing, the process jumps to (27b), and when not continuing, the process ends.

Embodiment 17 FIG. FIG. 28 is a flowchart showing a gradation processing method according to Embodiment 17 of the present invention.
Referring to FIG. 28, as an example of the gradation conversion program, a procedure for performing the function calculation of Expressions (13) and (14) by software will be described.

In (28a), the threshold value h and the constants a1,
a2 and a3 are stored in R1, R2, R3 and R4. (2
In 8b), the image data X is input and stored in R0.
In (28c), the difference between R0-R1 and R0-R4 is stored in R5 and R6. In (28d), the magnitudes of R0 and R1 are compared, and when R0> R1, the process jumps to (28f). In (28e), the product of R0 * R5 and R2 * R7 is stored in R7 and R8, respectively.

In (28f), R5 * R6 and R3 * R7
Are stored in R7 and R8, respectively. (28g)
The difference between 0 and R8 is stored in R9. In (28h), R9
Is output as converted data Y7. (28i)
Then, the continuation of the processing is determined. When continuing (28b)
Jumps to and terminates the process if not continued.

In the twelfth to seventeenth embodiments, a modification in which the order of steps is partially changed and a modification in which the number of registers is reduced can be performed. For example, this type of transformation
The step (23f) in the embodiment of FIG. 23 is a modification that is inserted between steps (23c) and (23d) to partially change the order of the steps and a modification that reduces the number of registers. Further, for example, as a modification in which some steps are pre-processed before a branch instruction, steps (27f) and (27g) in the sixteenth embodiment are inserted between steps (27b) and (27c). Is possible. Also, the number of registers can be reduced by using multiplexed registers.

Embodiment 18 FIG. FIG. 29 is an input / output characteristic diagram of a gradation processing apparatus according to Embodiment 18 of the present invention. Here, this is an example of an approximate characteristic when the data to be operated represented by Expression (1) is approximately realized by applying logarithmic operation.

The following equation (29) was used as the logarithmic equation. Y8 = Ymax · {log (X + 1) / log (Xmax + 1)} (29)

Here, when the input data X and the output data Y8 are 8 bits, a2 = Xmax = Ymax = 255, and approximate characteristics are a1 = -0.79 and a3 = 10. Further, in the drawing, the solid line indicates the approximate characteristic according to the equation (1), and the broken line indicates the theoretical value according to the equation (12). This logarithmic operation is often performed on the color separation data inside the scanner device.

Embodiment 19 FIG. FIG. 30 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 19 of the present invention.
The nineteenth embodiment corresponds to the conventional color conversion apparatus (FIG. 63), and the same reference numerals as in FIG. 63 denote the same parts.

In the figure, 30 is a complementer, 31 is an αβ calculator, 33 is a hue data calculator, 34 is a polynomial calculator,
110 is a coefficient generator, 111 is a matrix calculator, 1
13 is a synthesizer.

FIG. 31 shows a polynomial operation unit 34 shown in FIG.
FIG. 3 is a block diagram showing an example of the configuration of FIG. In the figure, 35
Is a zero remover, 36 and 37 are multipliers, 38 and 39 are adders, and 40 and 41 are dividers.

Next, the operation of the color conversion apparatus shown in FIG. 30 will be described. The complementer 30 receives the image data R, G, and B as input, and performs complement processing of one's complement to obtain complementary color data Ci, Mi, and Yi.
Is output. The αβ calculator 31 outputs a maximum value β and a minimum value α of the complementary color data and an identification code S for specifying each data. At this time, β = MAX (Ci, Mi, Y
i), α = MIN (Ci, Mi, Yi), and can be easily configured using a magnitude comparison circuit and a selector circuit.

The hue data calculator 33 calculates the complementary color data C
i, Mi, Yi and their maximum value α and minimum value β are input, and r = β-Ci, g = β-Mi, b = β-Yi and y = Yi-α, m = Mi-α, c = The six hue data r, g, b, y, m, and c are output by the subtraction processing of Ci-α. These six hue data have a property that at least two of them become zero.

Next, the operation of the polynomial operator 34 will be described with reference to FIG.
1 will be described. The zero eliminator 35 receives the hue data r, g, b, y, m, c and the identification code S as input, and outputs two non-zero data in the hue data r, g, b to Q1, Q2.
2, and two non-zero data in the hue data y, m, c are output as P1, P2. Multipliers 36 and 3
7 are the product T3 = Q1 * Q2 and the product T1 = P1 * P
2 is output. The adders 38 and 39 respectively add the sum Q1 +
Q2 and the sum P1 + P2 are output. The dividers 40 and 41 are
The quotient T4 = T3 / (Q1 + Q2) and the quotient T2 = T1 respectively
/ (P1 + P2) is output. These polynomial data T
1, T2, T3, and T4 are polynomial operators 34 (FIG. 31).
Output.

On the other hand, in FIG. 30, the coefficient generator 110 generates a matrix coefficient U (Fij) composed of polynomial data and a calculated matrix coefficient U (Fij) and a fixed coefficient based on the information of the identification code S. . here,
In (Eij), i = 1 to 3 and j = 1 to 3, and in (Fij), i = 1 to 3 and j = 1 to 12. The matrix calculator 111 calculates the hue data y, m, c and the polynomial data T
A matrix operation is performed using 1, T2, T3, T4 and a coefficient U as inputs, and the operation result of the following equation (30) is output as color ink data C1, M1, and Y1.

[0272]

(Equation 51)

Here, (Eij) is i = 1 to 3, j =
1 to 3 and (Fij) are i = 1 to 3 and j = 1 to 12
It is.

FIG. 32 is a block diagram showing an example of the configuration of the matrix calculator 111 shown in FIG. This matrix calculator 111 can be configured using a calculation block having the same or the same function as the calculation means described so far.

The matrix calculator 111 operates as follows. The multipliers 36, 37, 42 to 44 form the hue data c, the polynomial data T 1 to T 4 and the coefficients (Ei
j) and (Fij) are input and the product of each is output. The adders 38, 39, 45, and 46 receive the product and the sum thereof and output the sum as the color ink data C1. In the configuration example of the matrix calculator 111 of FIG. 32, if m and y are input to the multiplier 36 instead of the hue data c, the matrix calculation of the color ink data M1 or Y1 is executed.

In the coefficient generator 110, the polynomial data and the calculated matrix coefficient U (Fij) and the fixed coefficient matrix coefficient U (Eij) have coefficient values corresponding to the respective hue data c, m or y. Is used. That is, if three matrix calculators configured as shown in FIG. 32 are used in parallel, high-speed matrix calculation can be performed.

The synthesizer 113 outputs the color ink data C1, M
1, Y1 and achromatic color data α, and print data C,
M and Y are output. Therefore, an arithmetic expression for obtaining these print data C, M, and Y is given by the following expression (15).
Is represented by

[0278]

(Equation 52)

Here, (Eij) is i = 1 to 3, j =
1 to 3 and (Fij) are i = 1 to 3 and j = 1 to 12
It is.

It should be noted that the difference between each operation term in the equation (15) and the number of operation terms in the conventional matrix operation method is that the conventional method discloses an operation method for each pixel excluding zero data. In contrast, equation (15) discloses a general equation for a pixel set. Therefore, in the polynomial data of the above equation (15), 12 data can be reduced to 4 valid data for one pixel. This reduction is achieved by cleverly utilizing the properties of hue data.

The combination of valid data changes according to the image data of the pixel of interest, and all polynomial data is valid for all image data. There is an advantage that the number of times of multiplication for one pixel is smaller than the arithmetic expression of Expression (28).

FIG. 33 is a schematic diagram of hue data used in a matrix operation expression. This figure (A) thru | or (F)
Are six hues and hue data y, m, c, r,
6 schematically shows the relationship between g and b, and each hue data is related to three hues.

FIG. 34 is a schematic diagram of a multiplication term used in a matrix operation expression. These figures (A) to (F) show six hues and multiplication terms r * g, g * b, b * r, y, respectively.
It schematically shows the relationship among * m, m * c, and c * y, and it can be seen that the relationship is related to a specific hue.

For example, if W is a constant, y for red
= M = W, c = 0, so r = W, g = b = 0.
Therefore, y * m = W * W, and the other five terms are all zero. That is, for red, only y * m is a valid quadratic term. Similarly, c * y for green, m * c for blue,
Only g * b for cyan, b * r for magenta, and r * g for yellow are valid secondary terms.

Equations (30) and (15) above include a primary multiplication / division term valid for only one of each hue. The multiplication / division terms are r * g / (r + g), g * b / (g + b), b *
r / (b + r), y * m / (y + m), m * c / (m +
c), c * y / (c + y), and has the property of the first order term. For example, if W is a constant, y = m for red
= W, c = 0, so r = W, g = b = 0. At this time, m * y / (m + y) = W / 2, and the other five terms are all zero. Therefore, for red, only m * y / (m + y) is a valid first order term. Only one multiplication / division term is valid for other hues. If the numerator and denominator are zero, the first-order term is zero.

Table 1 below shows the relationship between the six hues and effective operation terms.

[0287]

[Table 1]

Here, the color conversion apparatus according to the nineteenth embodiment will be specifically described according to an actual application example.

FIG. 35 is an xy chromaticity diagram illustrating a characteristic example in which the color conversion apparatus of FIG. 30 is applied to a sublimation dye ink.
For example, the effect of applying the color conversion apparatus of the nineteenth embodiment to the calculation of the ink data of the sublimation dye used in the color video printer is shown on the xy chromaticity diagram. In the figure, broken lines indicate target characteristics of six hues, and solid lines indicate measurement results of print samples.

FIG. 35A shows a matrix coefficient (Ei
FIG. 11 is an xy chromaticity diagram when j) is set as shown in the following equation (31), and the coefficients of the matrix coefficients (Fij) are all zero. This condition corresponds to a case where color conversion is not performed.

[0291]

(Equation 53)

FIG. 35B shows a matrix coefficient (Fi
x when the numerical value shown in Table 2 below is used for the coefficient of j)
It is a y chromaticity diagram.

[0293]

[Table 2]

In this case, since the coefficients relating to the multiplication term are all set to 0, the correction is performed only by the multiplication / division term. The multiplication / division term has the effect of rotating the hue on the chromaticity diagram, thereby correcting the low chroma portion (center portion).
In FIG. 35B, the low chroma portion approaches the target characteristic, but deviates from the target characteristic in the middle to high chroma portions.

In the xy chromaticity diagram of FIG. 35 (C), the coefficient values shown in Table 3 below are set for each coefficient value of the matrix coefficient (Fij). That is, this is a graph in the case where correction is performed using all multiplication terms and multiplication / division terms.

[0296]

[Table 3]

The multiplication term has the function of correcting the characteristic curve on the xy chromaticity diagram, thereby correcting the middle to high chroma portion. In FIG. 35 (C), the target characteristics and the measurement results match well for the six hues. Thus, equation (3)
0) and Expression (15) can independently correct each hue. Since Equations (30) and (15) include the quadratic terms, the non-linearity of the print can be corrected.

Embodiment 20 FIG. FIG. 36 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 20 of the present invention.
This color conversion device has a function of removing a turbid component (achromatic component included in the color ink data) included in the color ink data and a function of finely adjusting the achromatic component ink data.
This is added to the color conversion apparatus of the nineteenth embodiment (FIG. 30). In the figure, reference numeral 47 denotes a nigori operation unit, reference numeral 48 denotes an achromatic color adjuster, and the other parts are denoted by the same reference numerals as those in FIG.

FIG. 37 is a block diagram of a configuration example of the nigori operation unit shown in FIG. Of the respective calculation means of the nigori calculator 47, the same reference numerals as those described above denote the corresponding calculation means, and reference numeral 50 denotes a calculation controller.

The color converter of the twentieth embodiment operates as follows. The color ink data C1, M1, and Y1 obtained by the calculation of the equation (30) are obtained by using the αβ
It is input to the calculator 32. Then, the color ink data C
The maximum value H and the minimum value L of 1, M1 and Y1 are extracted. The arithmetic controller 50 receives the maximum value and the minimum value as inputs, and when the minimum value L is positive (> 0), the L and the multiplication coefficient J (= H / (H− L)), and when L is zero or negative (≦ 0), L = 0 and J = 1 are output.

The subtractor 49 calculates the color ink data C1, M
1, Y1 and a conditional minimum value L are input, and the difference C6 = C
1-L, M6 = M1-L and Y6 = Y1-L are output.
Multipliers 36, 37 and 42 provide the differences C6, M6,
Y6 and the multiplication coefficient J are input, and the respective products are output as nigori removal data C5, M5, and Y5.

The general formula of this nigori operation is the following formula (3)
It can be expressed as 2).

[0303]

(Equation 54)

If the discontinuity of data occurring between pixels is allowed, the multiplication coefficient can be set to J = 1. In that case, the difference C6, M
6, Y6 are output as the nigori removal data C5, M5, Y5. As a result, even if the three multipliers 36, 37, and 42 are deleted, unnecessary turbid components can be removed.

Next, the function of finely adjusting the ink data of one achromatic component in the color conversion apparatus according to the twentieth embodiment will be described. The achromatic color adjuster 48 calculates the minimum value α as the achromatic data and the constant U1 (d1, d2, d3, d4, d
5, d6) to perform the calculation of the following equation (33).

[0306]

[Equation 55]

The result of this calculation is the achromatic color ink data C
2, M2, and Y2 are output to the synthesizer 113.

FIG. 38 shows the achromatic operation unit 48 shown in FIG.
It is a block diagram of an example of 1 structure. A constant U1 input to the achromatic color adjuster 48 for performing the operation of the equation (33) is generated by the coefficient generator 110. Multipliers 36a, 37a
And 42a output the products d4 * α, d5 * α, d6 * α. The adders 38, 39, and 45 respectively calculate the sum d4 * α
+ D1, d5 * α + d2, d6 * α + d3.
The multipliers 43, 44, and 51 output the calculation result of Expression (33), and finish fine adjustment of the quadratic function. Note that d4 = d5
= D6 = 0, the achromatic ink data C2, M
2 and Y2 are linear functions, and the achromatic operation unit 4
8 can be simplified.

By this fine adjustment, standard black, reddish black, bluish black and the like can be selected for printing, and a print image suitable for the user can be output by slightly changing the constant value.

In the color conversion apparatus according to the twentieth embodiment (FIG. 36), the sum C = C5 + C2 and M = M5 + M
2. Output Y = Y5 + Y2 as print data C, M, Y. Note that the nigori removal function and the fine adjustment function are independent of each other, and when only the former function is used, the print data C, M, and Y are C = C5 + α, M = M5 + α, and Y =
Y5 + α, and when only the latter fine adjustment function is used, C = C1 + C2, M = M1 + M2, and Y = Y1 + Y
It becomes 2.

Embodiment 21 FIG. FIG. 39 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 21 of the present invention.
Here, the corresponding circuits are indicated by the same reference numerals as those of the color conversion apparatus of FIG. 30. In addition to the elimination of the synthesizer 113, the polynomial operator 34 and the matrix operator 11
1 processing circuit is expanded. Details of these points will be described later.

This color conversion device is configured to realize the function operation of the following equation (18).

[0313]

[Equation 56]

Here, (Eij) is i = 1 to 3, j =
1 to 3 and (Fij) are i = 1 to 3 and j = 1 to 12
It is.

This equation (18) is obtained by integrating the functions of the equations (30) and (33) in the color conversion apparatus of the nineteenth embodiment (FIG. 30).

To execute this operation, one multiplier is added to the polynomial operation unit of the nineteenth embodiment (FIG. 31) to add the product α *
is output and the matrix computing unit of the nineteenth embodiment (FIG. 3)
2) adding two multipliers and two adders to the linear term d
The processing circuit may be extended so as to output a product such as 1 * α and the square term d4 * α * α and to add all data.

According to the equation (18), the sum of the corrected (modified) color ink data and the finely adjusted achromatic color ink data can be output. Note that the turbidity removal function cannot be used in the color conversion apparatus according to the twenty-first embodiment. When the turbidity removal function is required, the color conversion device of Example 20 (FIG. 36)
It is good to adopt.

In the above, the color conversion for obtaining the print data of three inks from the image data has been described. Next, in addition to cyan, magenta, and yellow, the image data is black (hereinafter, referred to as black).
Four-color conversion for converting print data of four inks including “K” will be described.

Embodiment 22 FIG. FIG. 40 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 22 of the present invention.
Here, corresponding circuits are indicated by the same reference numerals as those of the color conversion apparatus in FIG. 30, and 52 is a divider.

Next, the characteristic processing of this color conversion apparatus will be described. The αβ calculator 32 calculates the image data R,
The minimum value α of the complementary color data Ci, Mi, Yi generated from G and B is obtained in the same manner as in the case of the three-color conversion. Divider 52
Divides the minimum value α into black print data K and residual data (α−K). The print data K is directly output and used for printing with black ink. The residual data (α-K) is equivalent to achromatic data, is used for black printing produced by combining three inks of Y, M, and C, and is input to the polynomial calculator 34 and the matrix calculator 111. The polynomial calculator 34 outputs the product T5 = (α-K) * (α-K). The matrix calculator 111 calculates T5 and α-
Using K, print data C, M, and Y are obtained by the operation of the following equation (24). These C, M, Y, and K are output as print data.

[0321]

[Equation 57]

Here, in (Eij), i = 1 to 3 and j =
1 to 3 and (Fij), i = 1 to 3 and j = 1 to 14.

The color conversion apparatus according to the nineteenth embodiment (FIG. 30)
Is also possible, and this arithmetic expression is represented by the following expression (21).

[0324]

[Equation 58]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

Next, a method of dividing the minimum value α by a function operation will be described. The division formula of the quadratic function is the minimum value α
Using the print data K and the constants n and p, it can be expressed by the general formula of K = α−n * α * (p−α). Here, the constant n determines the maximum separation from the linear division, and p is equal to the maximum value of the input data. That is, the second term on the right side has a separation amount of zero when α = 0 and α = n.

The division formula of the cubic function is expressed by the general formula of K = α−n * α * (p−α) * (α + q) using the minimum value α, the ink data K, and the constants n, p, and q. it can.

FIG. 41 is a block diagram of a configuration example of the divider 52 shown in FIG. In the figure, 36, 37, 4
2 is a multiplier, 38 is an adder, 49 and 55 are subtractors, 53
Is a selector, and 54 is a constant generator.

The divider 52 operates as follows. The multiplier 36 outputs the product n * α. Subtractor 49
Outputs the difference (p−α). The adder 38 calculates the sum α + q
Is output. The multiplier 37 outputs the product n * α * (p−α). The selector 53 receives two data of the sum α + q and the numerical value = 1 generated by the constant generator 54 as input, and outputs any one of the data corresponding to the function selection signal.

When the output data of the selector 53 is the sum α + q, the multiplier 42 outputs the product n * α * (p−α) * (α + q)
Is output. When the output data is numerical value = 1, the product n
* Α * (p-α) is output. The output of the multiplier 42 is α
-K. The output of the subtractor 55 becomes K. In this way, the print data K and the residual data α-K are obtained.

FIGS. 42A and 42B are diagrams showing examples of characteristics obtained by dividing achromatic data used by the color conversion apparatus shown in FIG. 40 by a functional expression. The function selection signal input from the outside to the selector 53 is a selection signal of a quadratic function or a cubic function. In the case of FIG. 42 (A), the quadratic function is monotonic, whereas in the case of FIG. 42 (B), the cubic function can realize complicated division characteristics.

Also, print data K obtained by a function operation of a computer is stored in a memory in advance, K is obtained by table conversion using a minimum value α as an input, and a difference between the minimum value and K is output. And the splitter 52 can be realized similarly. According to this configuration, the scale of hardware can be reduced. For example, in the configuration of the divider shown in FIG. 41, about 2,000 gates are required, but it can be reduced to about 500 gates. That is,
When the division characteristic is 3 or less, the table conversion method is advantageous. Further, there is an effect that a complicated division characteristic which cannot be realized by the above quadratic function or cubic function can be realized.

Embodiment 23 FIG. FIG. 43 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 23 of the present invention.
Here, corresponding circuits are indicated by the same reference numerals as those of the color conversion apparatus of FIG. 36, and 56 is a conversion controller. The conversion controller 56 includes a divider 52, a coefficient generator 1
10, connected to the arithmetic operation unit 47 and the achromatic color adjuster 48, and predetermined data is input or set to each block.

The color conversion apparatus has a function of freely selecting a color conversion processing mode.
There are the following modes (A) to (F). (A) Selection mode of three-color conversion and four-color conversion (B) Selection mode of using or not using nigori removal function (C) Selection mode of using or not using the function of finely adjusting achromatic components (D) Selection mode of what kind of fine adjustment function to use (E) Selection mode of division function and setting of corresponding constants (F) Selection of plural ink sets and setting mode of matrix coefficient

The following is a brief description of these modes. (A) is a three-color conversion if black print data output from the divider 52 is processed as K 変 換 0. Otherwise, the operation is a four-color conversion operation. (B) shows the operation controller 50 used in the nigori operation unit (FIG. 37) of the twentieth embodiment.
If the output of L is set to L≡0 and J≡1, the processing will not use the nigori removal function. (C) is a mode in which the adjustment function is not used by setting the coefficients output from the coefficient generator 110 to d1 to d3≡1 and d4 to d6≡0. (D)
Coefficients output from the coefficient generator 110 are standard black coefficients,
This can be realized by selectively setting a reddish black coefficient and a bluish black coefficient. In (E), one of the functions can be selected by the function selection signal of the divider 52. It can also be realized by previously writing table conversion data with arbitrary characteristics in the memory. The function (A) can also be realized by this method.

(F) shows that the ink discriminator provided in the conversion controller 56 specifies one of a plurality of ink sets, and the coefficients (Eij) and (Fij) corresponding to the specified ink set.
Is instructed to the coefficient generator, a plurality of inks can be freely selected and used.

The ink can be identified by a method of reading an identification mark pre-processed on the ink ribbon by an optical or magnetic means, or a method of manually setting using an interface between the apparatus and a person. There is.

As described above, only by adding the conversion controller 56, various functions or desired performance can be easily realized, and the flexibility of color conversion can be greatly improved. It should be noted that a general-purpose 8-bit CPU is sufficient for the conversion controller 56, and does not significantly increase the cost.

Embodiment 24 FIG. FIG. 44 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 24 of the present invention.
This color conversion device is the same as the color conversion device of the nineteenth embodiment (FIG. 30).
And the matrix calculator 111 in
Is reduced in circuit scale. Here, circuits corresponding to those of the color conversion apparatus of FIG. 30 and the polynomial operation unit of FIG. 31 are indicated by the same reference numerals, 57 is a first multiplexer, 58 is a second multiplexer, and 59 is a cumulative multiplier. It is a vessel.

An operation characteristic of this color conversion device will be described. The input image data is decomposed into six hue data, achromatic data, and an identification code S as in FIG. The zero remover 35 outputs valid data Q1, Q2, P1,
P2 is output. The first multiplexer 57 performs time division multiplexing of P1 and P2 or Q1 and Q2. The multiplier 36 calculates the product P1
* P2 or Q1 * Q2 is output. The adder 38 calculates P
1 + P2 or Q1 + Q2 is output. The divider 40
P1 * P2 / (P1 + P2) or Q1 * Q2 / (Q1
+ Q2) is output. Second multiplexer 58
Is the hue data c, m, y, the product P1 * P2 or Q1 *
Q2 and the multiplication / division data from the divider 40 as inputs,
They are time-division multiplexed.

FIG. 45 is a diagram for explaining the outline of time-division calculation in the color conversion apparatus of FIG. FIG.
(B) and (C) respectively show color ink data C1 and M
It is a multiplexing example in the operation of 1, Y1. FIG.
(D) is an example of multiplexing of coefficients.

The first multiplexer 57 is switched at the position Z shown in the figure so that the operation can be performed smoothly.
The accumulative multiplier 59 is calculated by the equation (30) in the nineteenth embodiment.
Is performed in a time-division manner to obtain color ink data C1. The color ink data M1 and Y1 are sequentially obtained by a similar operation. The synthesizer 113 has C = C1 + α, M = M1 + α, Y
= Y1 + α is sequentially output.

If the achromatic data is input to the second multiplexer 58 and the coefficient generator 110 is modified to generate the corresponding multiplication coefficient = 1, the synthesizer 113 can be eliminated.

As described above, by performing the time division operation using the multiplexer, the circuit scale of the color conversion apparatus according to the nineteenth embodiment can be greatly reduced. For example, assuming that the circuit scales of the multiplier and the divider are five hundred gates and six hundred gates, respectively, the color converter of the nineteenth embodiment (FIG. 30) has a scale of 10,000 gates or more. Is the color conversion device of Embodiment 24 (FIG. 4).
In 4), it can be made 3,000 gates or less. Therefore, in a color conversion device that employs the YMC face-sequential printing method, such as a color video printer, a configuration like the color conversion device of this Embodiment 24 (FIG. 44) is suitable.

The arithmetic expression for color conversion is not limited to the arithmetic expression (30) and the arithmetic expression (15) in the nineteenth embodiment, and other arithmetic expressions can be employed. For example, a multiplication / division term in Table 4 below may be used instead of the multiplication / division term in the operation expression (30).

[0346]

[Table 4]

Note that the denominator of the multiplication / division term in Table 4 is (g +
Even if it is changed to m) or (b + y), it becomes an equation equivalent to the arithmetic expression (30) in the nineteenth embodiment.

In addition, the arithmetic expression (30) in the nineteenth embodiment is obtained.
When the multiplication / division term in Table 4 is employed instead of the multiplication / division term, the following equation (34) is used.

[0349]

[Equation 59]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

In this case, the arithmetic expression for obtaining the print data is:
The operation expression is as shown in the following expression (17).

[0352]

[Equation 60]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

Also, the arithmetic expression (30) in the nineteenth embodiment is used.
In place of the multiplication / division term, the square root of the multiplication term can be adopted, and the arithmetic expression at this time is as follows:

[0355]

[Equation 61]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

In this case, the arithmetic expression for obtaining the print data is as shown in the following expression (16).

[0358]

(Equation 62)

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

FIG. 46 is a schematic diagram for explaining the difference in the operation terms of the matrix operation formula in the color conversion apparatus of FIG. FIG. 7A shows data y * c / (r) for each hue.
+ C) is schematically shown, and changes linearly in the yellow to green and green to cyan regions. FIG. 6B schematically shows the size of the data y * c / (y + c). Compared to FIG.
The data increases in the green to cyan area. That is, y
The effect of y * c / (y + c) on yellow-green and green-cyan areas is greater than * c / (r + c).

[0361] Also, FIG. 47C schematically shows the size of the data √ (y * c). Here, in each of the yellow to green and green to cyan regions, the value becomes even larger, and the influence of the color conversion is large. Therefore, it is necessary to select an operation term according to the required characteristics for color conversion.

Also, the arithmetic expression (18) in the twenty-first embodiment
If the multiplication / division terms in Table 4 are used instead of the multiplication / division terms in (1), the operation expression for obtaining the print data is the operation expression shown in the following expression (20).

[0363]

[Equation 63]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
14.

In addition, the operation expression (24) in the twenty-second embodiment
When the multiplication / division terms in Table 4 are employed instead of the multiplication / division terms in (2), the operation equation for obtaining the print data is the following equation (26).

[0366]

[Equation 64]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
14.

In addition, the arithmetic expression (21) in the twenty-second embodiment
If the multiplication / division terms in Table 4 are employed instead of the multiplication / division terms in (2), the operation equation for obtaining the print data is the following equation (23).

[0369]

[Equation 65]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

Also, the arithmetic expression (18) in the twenty-first embodiment
If the square root of the multiplication term is adopted instead of the multiplication / division term, the operation expression for obtaining the print data is the operation expression shown in the following expression (19).

[0372]

[Equation 66]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
14.

Also, the operation expression (24) in the twenty-second embodiment
If the square root of the multiplication term is used instead of the multiplication / division term, the operation expression for obtaining the print data is the operation expression shown in the following expression (25).

[0375]

[Equation 67]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
14.

In addition, the arithmetic expression (21) in the twenty-second embodiment
If the square root of the multiplication term is adopted instead of the multiplication / division term, the operation expression for obtaining the print data is the operation expression shown in the following expression (22).

[0378]

[Equation 68]

Here, in (Eij), i = 1 to 3, j
= 1 to 3 and (Fij), i = 1 to 3 and j = 1 to
Twelve.

Embodiment 25 FIG. FIG. 47 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 25 of the present invention.
In the figure, corresponding circuits are indicated by the same reference numerals as those of the color conversion apparatus of the twenty-fourth embodiment (FIG. 44), and 19 is a square root device. This color conversion apparatus is configured to process the arithmetic expression (33) in the twentieth embodiment by a time division operation.

The operation of this color conversion apparatus is similar to that of Embodiment 24 except that the outputs が (Q1 * Q2) and √ (P1 * P2) of the square rooter 60 are used.
The operation is the same except for the multiplication / division term of the color conversion device (FIG. 44), and the description is omitted.

The arithmetic expression (15) in the nineteenth embodiment is obtained.
May be used in place of the multiplication / division term.

[0383]

[Table 5]

FIGS. 48 (A) to (E) are schematic diagrams for explaining the difference in the operation terms of the matrix operation formula in the color conversion apparatus of FIG.

The multiplication / division terms in Table 5 have the following effects according to the ratio between the variables s and t. For example, the multiplication / division term y * c / (s2 * y + t2 * c) in the green hue is shown in FIG.
As shown in FIG. 8, yellow to yellow according to the ratio of s2 to t2.
The effect on the green region is different from the effect on the green-cyan region. FIG. 48A shows s2: t2 = 4:
1, FIG. 48 (B) shows the case where the ratio is set to 2: 1, FIG. 48 (C) shows the case where the ratio is set to 1: 1, FIG. 48 (D) shows the case where the ratio is set to 1: 2, and FIG.

The same applies to the other five hues. In addition, the color conversion device that realizes this function formula is also the color conversion device of the nineteenth embodiment (FIG. 30) and the color conversion device of the twenty-fourth embodiment (FIG. 4).
It can be easily realized with reference to 4).

The operation used by the nigori operation unit 47 is as follows.
If the minimum value H of the color correction data has a positive value, any method may be used as long as at least one of the color correction data is subtracted to 0 using H. For example, when H> 0, a practically sufficient effect can be obtained by subtracting the minimum value H from data not equal to the maximum value L in the color correction data.

Embodiment 26 FIG. FIGS. 49 to 52 are flowcharts showing a color conversion method according to a twenty-sixth embodiment of the present invention. This color conversion program is expressed as a flowchart for performing the color conversion processing of the equation (15) by software. In step a of FIG. 49, the coefficient (Eij) is set in registers R0 to R8 built in the CPU. ing.

In step b, the coefficient (Fij) is set in the registers R9 to R44. The suffix c such as the coefficient (F1 c) in step b indicates a hexadecimal number. In step c, the image data R, G, and B for one pixel are stored in registers R50, R51, and R52, respectively. In step d, each of the image data R, G,
A one's complement process is performed on B, and the result is stored in registers R53, R54, and R55 as complementary color data.

In step e, the minimum value α of the complementary color data is obtained and stored in the register R56, and the minimum value is identified and the numerical values 0, 1, and 2 are set in the register R57.
This will be described later in detail with reference to a subroutine (FIG. 53). In step f, hue data c, m, and y are obtained and stored in registers R58, R59, and R60. In step g, the maximum value β is obtained and stored in the register R61, and numerical values 0, 1, and 2 for identifying the maximum value are set in the register R62. This will be described later in detail with reference to a subroutine (FIG. 54).

In the step h of FIG. 50, the hue data r,
g and b are obtained and stored in registers R63, R64 and R65, respectively. At steps i1 and i2, the register R5
A conditional jump is performed by the numerical value of 7. Step j
In 1 to j3, data obtained by removing zeros from the hue data c, m, and y are stored in registers R66 and R67 as P1 and P2.

At steps k1 and k2, the register R62
A conditional jump is performed by the numerical value of. Step l1
In steps l3 to l3, the data obtained by removing the zeros in the hue data r, g, b are stored in registers R68 and R69 as Q1 and Q2. In step m, the product P1 * P2 and Q1 * Q2 and the sum P1 + P2 and Q1 + Q2 are calculated and the register R7
0, R71, R72, and R73. Also, quotients T2 and T4 are obtained from the product and the sum, and
4 and stored in R75.

In steps n1 and n2 of FIG. 51, a conditional jump is performed using the identification value of the minimum value. In steps o1 to o3, coefficients (F
ij) is stored in the registers R76 to R81. The coefficients actually used are selected based on the hue data. In steps p1 and p2, a conditional jump is performed based on the identification value of the maximum value. In steps q1 to q3, coefficients (Fij) corresponding to the respective conditions are stored in registers R82 to R87. The coefficients actually used are selected based on the hue data.

In step r of FIG. 52, the coefficient (Eij)
And hue data c, m, y are subjected to a matrix operation, and the results are stored in registers R90, R91, R92.
In step s, a matrix operation of the coefficient (Fij) and the multiplication term and the multiplication / division term is performed, and the result is stored in the register R9.
3. Store in R94 and R95. At step t, the calculation results at steps r and s are respectively added, and
96, R97, and R98 have color ink data C1, M1, and Y
Stored as 1.

In step u, the color ink data C1, M
1 and Y1 are corrected. This will be described later in detail with reference to a subroutine (FIG. 55). In step v, the achromatic component is adjusted. This will be described later in detail with reference to a subroutine (FIG. 56). In step w, a final ink data output process is performed. This will be described later in detail with reference to a subroutine (FIG. 57).
In step x, when performing the same processing for the next pixel, the process jumps to point D. If not, the process ends.

Each of FIGS. 53 to 57 is a flowchart of a subroutine for executing the color conversion method of the twenty-sixth embodiment.

FIG. 53 shows the subroutine for setting the sign of the minimum value in detail. The procedure for storing the minimum value in the register R56 and setting the identification value in R57 is shown. In step ea, the complementary color data is stored in the register R56, and the numerical value (00H) is stored in the register R57.
At step eb, the conditional jump is performed by comparing the complementary color data stored in the register R56 with another complementary color data. In step ec, another complementary color data is stored in the register R
56, and the numerical value (01H) is stored in the register R57. In step ed, the complementary color data stored in the register R56 is compared again with another complementary color data, and a conditional jump is performed. In step ee, a conditional jump is performed by comparing the first complementary color data with another complementary color data. In step ef, the minimum complementary color data is stored in the register R56, and the numerical value (02H) is stored in the register R5.
7 is stored.

FIG. 54 shows the subroutine for setting the sign of the maximum value in detail. The procedure for storing the maximum value in the register R61 and setting the identification value in R62 is shown. In step ga, the hue data is stored in the register R61, and the numerical value (00H) is stored in the register R62.
At step gb, the hue data stored in the register R61 is compared with another hue data, and a conditional jump is performed. In step gc, the first hue data is compared with yet another hue data to perform a conditional jump. In step gd, another hue data is stored in the register R61, and a numerical value (01H) is stored in the register R62. At step ge, the hue data stored in the register R61 is compared again with another hue data, and a conditional jump is performed. In step gf, the maximum hue data is stored in the register R61, and the numerical value (02H) is stored in the register R6.
Stored in 2.

FIG. 55 shows details of the subroutine for nigori correction. In step ua, the minimum value of the color ink data is stored in the register R99. Step u
In b, the maximum value of the color ink data is stored in the register R100. In step uc, the registers R101, R1
02 and R103 are stored with the color ink data. In this step, data when no nigori correction is performed is set in a register in advance, which is effective in simplifying the floater. In step ud, it is determined whether or not to perform nigori correction. In step ue, the multiplication coefficient J is obtained, and the result is stored in the register R105. Step uf
Then, the minimum value is subtracted from the color ink data, and the respective results are stored in registers R106, R107, and R108. In step ug, the ink data that has been subjected to the lag correction is obtained using the data stored in steps ue and uf, and is stored in the registers R101, R102, and R103 as lag removal data.

FIG. 56 shows details of the subroutine for achromatic color adjustment. At step va, one of a linear function and a quadratic function is selected and jumped. Step vb
Then, the adjustment coefficients d1, d2, and d3 of the linear function are stored in the registers R111, R112, and R113. Step v
In c, the achromatic data is multiplied by the adjustment coefficient, and the adjusted data is stored in the registers R120, R121, and R122. In step vd, the adjustment coefficients d1 to d6 of the quadratic function are stored in the registers R111 to R116.
In step ve, a quadratic function adjustment operation is performed, and the adjusted data is stored in the registers R120, R121, and R122. In this manner, the achromatic data can be adjusted, and a desired black can be selected from reddish black, standard black, bluish black, and the like. If no adjustment is made, a linear function may be selected and the adjustment coefficient may be set to d1 = d2 = d3 = 1.

FIG. 57 shows details of the subroutine of the output processing. At step wa, the nigori removal data and the achromatic color adjustment data are added, and the sum is added to the register R13.
0, R131 and R132. At step wb, the data in the registers R130, R131, R132 is output from predetermined ports as print data C, M, Y.

As described above, the color conversion by the operation formula (15) realized in the color conversion apparatus according to the nineteenth embodiment can be similarly executed in the calculation by software processing.
Further, other function operations can be similarly realized by software processing.

Embodiment 27 FIG. FIG. 58 is a block diagram showing a color conversion apparatus which is Embodiment 27 in which the invention is applied to a scanner apparatus. Here, corresponding circuits are indicated by the same reference numerals as those of the color conversion apparatus of FIG.

This color conversion apparatus is obtained by removing the complementer 30 from the color conversion apparatus of the nineteenth embodiment, and is assumed to be applied to color conversion of color separation data from a scanner. Many recent color scanners use a CCD line sensor with a color filter. In this type of scanner apparatus, there are many line sensors using R, G, and B filters. However, there is a problem that such a color filter cannot freely set light transmission characteristics. For this reason, it is necessary to convert the color of the output signal of the sensor to obtain an image signal for display.

Therefore, in this color conversion apparatus, the output signal of the sensor is digitized to obtain the sensor data Rin, Gi.
n and Bin are input. This type of data is assumed as an input to the color conversion device of FIG.
On the other hand, the output of this color conversion device is the color separation data Rou.
t, Gout, and Bout. Under these conditions, Example 1
If the data processing is executed in the same manner as in the color conversion apparatus 9 (FIG. 30), corrected (modified) color separation data is obtained. This color separation data is the image data itself.

Also, there is a sensor using a C filter, an M filter, and a Y filter as a color filter. In this case, the color conversion apparatus of the nineteenth embodiment (FIG. 30) is used, and the sensor data Ci is used instead of the image data R, G, and B.
If n, Min, and Yin are input and the print data C, M, and Y are output as color separation data Rout, Gout, and Bout, color conversion can be similarly performed.

Therefore, in order to execute various color conversions, a direct output mode and an inverted output mode of input data are added to the complementer 30 of the color conversion apparatus of the nineteenth embodiment (FIG. 30). By transforming so that either one can be selected, a general-purpose color conversion function can be realized. These color converters are
It can be easily realized by using an EX-OR logic circuit or the like.

The color conversion device of the present invention can be widely applied to realize various conversion functions as described below. (1) Function to convert image data to print data (2) Function to convert image data to display data (3) Function to convert sensor data to color separation data or image data (4) First image data to (5) Function of converting first print data to second print data (6) Function of converting first color separation data to second color separation data (7) Color A function to unify or match the color reproduction characteristics of at least three data of decomposition data, image data, print data, and display data

The function (1) is suitable for outputting print data to a color printer or a color video printer. The function (2) is suitable for outputting display data having been subjected to color reproduction correction to a standard image monitor, a liquid crystal type or a CRT type projector, or the like. The function of (3) is
It is suitable for outputting sensor data from a color scanner as color separation data or image data. The function (4) is suitable for data conversion between an NTSC image and a Hi-Vision image. The function (5) is suitable for data conversion between a commercial printing press and a simple printing press. The function (6) is suitable for a process of converting color separation data again into good color separation data. The function (7) is suitable for unifying or matching color reproduction characteristics in an image processing personal computer, an electronic publishing press, and the like. Further, it can be used not only for the device itself but also for an integrated system.

Embodiment 28 FIG. FIG. 59 is a block diagram showing a configuration of an image processing apparatus according to Embodiment 28 of the present invention. In the following, the gamma characteristic of the input image data is
in, γ for gradation processing, Γout for gamma characteristic of output device
It is defined and explained.

FIG. (A) shows the case of an image device that outputs image data of Γin = 1, and FIG.
Video devices that output 2.2 image data are classified.

In the transmission of video data of the NTSC system, C
In order to compensate for the intrinsic characteristic Γout = 2.2 of the RT display, compensation by the gamma characteristic of に よ る in = 1 / 2.2 is performed on the image transmission side. That is, a scanner device is a typical image device in the drawing, and a TV device is a typical video device.

In the figure, reference numeral 61 denotes an image device, 62 denotes a video device, 63 denotes a gradation processing device, 64 denotes a CRT display, and 65 denotes a CRT display.
Is a PDP (plasma display panel) display,
66 is an LCD display, and 67 to 71 are gradation processing devices having first to fifth gradation characteristics.

The CRT display 64 shown in FIG.
* Γ * Γout = 1, the gradation processing device 67 of γ = 1 / 2.2 is required. The PDP display 65 displays {out =
1 and can be displayed directly. The LCD display 66 requires a non-linear gradation processing device 69 as shown.

[0415] The CRT display 64 of FIG.
Since * γ * Γout = 1, direct display is possible. PDP
The display 65 requires a gradation processing device 70 of γ = 2.2. Further, the LCD display 66 requires a gradation processing device 71.

[0416] As another type of image output device, there is a video printer device, which is often designed with a gradation characteristic of $ out = 1, and performs gradation processing similar to that of the PDP display 65.

In the above description, the total gradation characteristic 階 調 in * γ
* Γout = 1, that is, in the case of an image processing apparatus on the premise of faithful image transmission, other total gradation characteristics may be required.

For example, among the lightness characteristics taking into account the human luminosity characteristics, there is the L ^* a ^* b ^* color system recommended by the International Commission on Illumination (CIE) in 1976, which most closely matches human perception. This lightness L ^* is proportional to the 1/3 power of the luminance data of γ = 1 representing the luminance component of the video data, and has a gradation characteristic of γ = 1/3.

[0419] Accordingly, in the total gradation characteristic taking into account such visibility characteristics, if Γin * γ * Γout = 1/3, a real image with a sense of existence can be displayed or printed. In the case of gamma-corrected luminance data of Γin = 1 / 2.2, γ =
An operation of 2.2 / 3 = 1 / 1.36 is required.

FIG. 60 is a block diagram showing a modified configuration of the image processing apparatus according to the twenty-eighth embodiment of the present invention.
Here, γ = 1 / 6.6, γ = 1/3, γ = 2.2 /
3 and the LCD display 66 require higher-order gradation processing. FIG. 3A shows a case of an image device that outputs image data of Γin = 1, and FIG. 2B shows a case of a video device that outputs image data of Γin = 1 / 2.2. I have. In the figure, reference numerals 72 to 76 denote sixth to tenth gradation processing devices. Other points are the same as those described above, and the details are omitted.

[0421] The CRT display 64 of FIG.
* Γ * Γout = １ ／ The gradation processing device 72 of γ = 1 / 6.6 is required. The PDP display 65 indicates that γ = 1
A 階 調 gradation processor 73 is required. LCD display 6
6 requires a non-linear gradation processor 74.

The CRT display 64 shown in FIG.
A 階 調 gradation processor 73 is required. PDP display 6
5 requires a gradation processing device 75 of γ = 2.2 / 3,
The LCD display 66 requires a gradation processing device 76.

However, the calculation such as γ = 1 / 6.6 is 2
A lot of non-appearance data is generated for input image data of 56 gradations, resulting in false contours, which degrades image quality. Therefore, there is a demand for gradation processing in which the visibility characteristics and the number of input bits of image data are harmonized.

Further, the gradation processing of the S-shaped characteristic has a feature that the contrast characteristic is increased and a visually excellent image can be output. The arithmetic expression (4) is effective for this gradation processing.

The gamma characteristic of a CRT display is
It has been reported by academic societies that the range of 1.5 <、 out <4 is satisfied, and 1/4 <γ <1 /
A gradation characteristic of 1.5 or 2.2 / 4 <γ <2.2 / 1.5 is required.

Furthermore, color matching between the image-related equipment, the video-related equipment, and the printing-related equipment, which has a problem of gradation reproducibility and color reproducibility, is also becoming a problem, and the gradation characteristics of each device are unified. Processing is required.

As described above, a gradation processing method using a function operation is effective in responding to various requests for gradation processing, and the present invention provides one solution.

Also, according to the input / output characteristics specific to the device,
Since gradation processing can be executed flexibly, appropriate gradation processing can be executed for any system configuration. Note that a plurality of function operation expressions can be selectively used in the same device according to the purpose.

Further, the present invention relates to image data of RGB color system used in personal computers and the like, luminance data and color difference data used in video equipment, yellow Y / magenta M / cyan C used in printing equipment. / Black Bk color system can be applied to gradation processing.

[0430]

The image processing method and apparatus according to the present invention are configured as described above, and have the following effects.

According to the image processing method of the first aspect, the operated data Y is a first-order term, a second-order term, or a third-order term of the image data X.
By adopting a function operation expression expressed using at least two of the following terms or multiplication and division terms,
Two or more primary components, secondary components, and multiplication / division components can be given to gradation characteristics, the same function can be realized by both hardware and software, and several constants are changed. Only with this, an arbitrary gradation characteristic can be realized.

According to the image processing method of the second aspect, the data Y to be operated is obtained by using the image data X and the constants a1, a2, and a3, Y = X + a1.X. (X-a2) / (X + a3) or Y = X · ｛1 + a1 · (X−a2) / (X + a
3) Since the function operation expression expressed by｝ is adopted, the gradation
A next component and a (secondary / first-order) multiplication / division component can be given, and furthermore, arbitrary gradation characteristics can be flexibly realized only by changing the values of a1, a2 and a3.

According to the image processing method of claim 3, (A)
Generating constants a1, a2 and a3; (B) difference (X-a2) and sum (X + a) from image data X and the constant;
3C), and (C) a modification amount a1 · X · (X−a2) / (X) from the image data, the difference and the sum, and the constant.
+ A3), and (D) a step of calculating the operated data Y from the image data and the modification amount, so that the function operation is executed by a program, and a1, a2, a
By simply changing the numerical value of 3, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing method of the fourth aspect, (A)
Generating constants a1, a2 and a3; (B) difference (X-a2) and sum (X + a) from image data X and the constant;
3C); (C) modifying coefficient 1 + a1 · (X−a2) / from the image data, the difference and the sum, and the constant;
Since (D +) the step of obtaining (X + a3) and the step of (D) obtaining the operated data Y from the image data and the modification coefficient, a function operation is executed by a program, and a1, a
By simply changing the numerical values of 2 and a3, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing method of the fifth aspect, the operated data Y is the same as the image data X and the constants a1, a2, a3, a
Y = X + a1.X. (X-a2). (X-a3) / (X
+ A4) or Y = X ｛1 + a1 ・ (X-a2) ・ (X-a
3) Since the function operation expression represented by / (X + a4)｝ is adopted, the gradation characteristic has 1
A next component and a (third-order / first-order) multiplication / division component can be provided, and furthermore, an arbitrary gradation characteristic can be flexibly realized only by changing the values of a1, a2, a3, and a4.

According to the image processing method of claim 6, (A)
Generating constants a1, a2, a3, a4;
(B) a difference (X-a2) between the image data X and the constant,
(X-a3) and sum (X + a4);
(C) A modification amount a1, X, (X-a2), (X-a3) / (X + a4) from the image data, the difference and the sum, and the constant.
, And (D) a step of calculating the operation target data Y from the image data and the amount of modification, so that the function operation is executed by a program, and a1, a2, a3, a4
It is possible to flexibly realize an arbitrary gradation characteristic only by changing the numerical value of.

According to the image processing method of the present invention, (A)
Generating constants a1, a2, a3, a4;
(B) a difference (X-a2) between the image data X and the constant,
(X-a3) and sum (X + a4);
(C) From the image data, the difference and the sum, and the constant, the modification coefficient 1 + a1 · (X−a2) · (X−a3) / (X + a)
4), and (D) a step of calculating the operation target data Y from the image data and the modification coefficient.
By simply changing the numerical values of 3 and a4, an arbitrary gradation characteristic can be flexibly realized.

[0438] According to the image processing method of the eighth aspect, the operated data Y is the image data X and the constants a1, a2, a3, a
Y = X + a1 · X · (X−a2) + a3 · X · (X−a
2) · (X−a4) / (X + a5) or Y = X · ｛1 + a1 · (X−a2) + a3 · (X
−a2) · (X−a4) / (X + a5)}.
A second component, a second component, and a (third / first) multiplication / division component can be given, and further, a1, a2, a3, a4
By simply changing the value of a5, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing method of the ninth aspect, (A)
Generating constants a1, a2, a3, a4, and a5; (B) calculating a difference (X-a
2), a step of obtaining a sum (X + a5) and (X-a4); (C) a modification amount a1 · X · (X−a2) + a3 · X · (X−a2) from the image data, the difference and the sum, and the constant; )
A step of calculating (X−a4) / (X + a5),
(D) Since the method includes a step of obtaining the operation target data Y from the image data and the modification amount, the function operation is executed by a program, and only by changing the numerical values of a1, a2, a3, a4, and a5, an arbitrary floor is obtained. Tone characteristics can be flexibly realized.

According to the image processing method of the tenth aspect,
(A) a step of generating constants a1, a2, a3, a4, and a5; and (B) a difference (X−a) between the image data X and the constant.
2) calculating (X-a4) and the sum (X + a5); (C) modifying coefficients a1, (X-a2) + a3, (X-a2) and (X) from the image data, the difference and the sum, and the constant;
-A4) / (X + a5), and (D) a step of calculating the operation target data Y from the image data and the amount of modification.
Just by changing the numerical values of a1, a2, a3, a4, a5,
Arbitrary gradation characteristics can be flexibly executed.

According to the method of the eleventh aspect, a primary component and a tertiary component can be given to the gradation characteristic by an operation mainly based on multiplication and addition, and furthermore, only by changing the values of a1, a2 and a3 Thus, an arbitrary gradation characteristic can be realized more flexibly.

According to the method of the twelfth aspect, the amount of modification to the image data is changed by the numerical values of a1, a2, and a3, and a function operation for realizing an arbitrary gradation characteristic can be executed by a program.

According to the method of claim 13, the modification coefficient of the image data is changed by the numerical values of a1, a2, and a3.
A function operation for realizing an arbitrary gradation characteristic can be executed by a program.

According to the method of the fourteenth aspect, a primary component and two types of tertiary components can be given to the gradation characteristics by an operation mainly comprising multiplication and addition.
By simply changing the values of a4 and a5, an arbitrary gradation characteristic can be realized more flexibly.

According to the method of the fifteenth aspect, it is possible to change the amount of modification to the image data by the numerical values of a1, a2, and a3 and execute a function operation for realizing an arbitrary gradation characteristic by a program.

According to the method of the sixteenth aspect, the modification coefficient of the image data is changed by the numerical values of a1, a2, and a3.
A function operation for realizing an arbitrary gradation characteristic can be executed by a program.

According to the method of the seventeenth aspect, a primary component and two tertiary components selected on the basis of the threshold value h are given to the gradation characteristic by an operation mainly based on multiplication and addition. And a1, a2, a3, a4, a5
By simply changing the value of, arbitrary gradation characteristics can be realized more flexibly.

According to the method of the eighteenth aspect, the amount of modification to the image data is determined by the threshold value h and a1, a2, a3, a4.
By changing the numerical value of a5, a function calculation for realizing an arbitrary gradation characteristic can be executed by a program.

According to the method of the nineteenth aspect, a primary component and two tertiary components selected on the basis of the threshold value h are given to gradation characteristics by an operation mainly based on multiplication and addition. Further, by simply changing the values of a1, a2, and a3, an arbitrary gradation characteristic can be realized more flexibly.

According to the twentieth aspect, the amount of modification to image data is changed by the threshold value h and the numerical values of a1, a2 and a3, and a function operation for realizing an arbitrary gradation characteristic is performed by a program. I can do it.

According to the image processing method of the twenty-first aspect, by varying the value of the constant of each function expression, it is possible to flexibly execute gradation processing with arbitrary characteristics.

According to the image processing method of the twenty-second aspect, there is provided a step of changing the numerical value of the constant of each function expression, and it is possible to execute gradation processing of an arbitrary characteristic.

According to the image processing method of the twenty-third aspect, the function operation expression for gradation conversion can be calculated by an approximate value of logarithmic operation. Therefore, it is suitable for, for example, gradation processing of color separation data in a scanner device.

According to the image processing method of the twenty-fourth aspect, achromatic data and six hue data are generated from the image data.
A color conversion process capable of independently correcting (modifying) each hue is realized by a new matrix operation expression. Therefore, the image data R, represented by three colors of red, green, and blue,
G, B, etc. are subjected to color conversion processing for each pixel, color ink data and achromatic color data α are added, and when print data C, M, Y expressed by three ink colors are output, the There is no mutual interference of calculations between colors and hues, so the six hue regions of image data R, G, B and print data Y, M, C can be corrected independently, and the conversion characteristics by matrix calculation can be flexibly changed. it can.

According to the twenty-fifth aspect, the achromatic color data α is similarly added to the color ink data color-converted for each pixel by a new matrix operation formula including a calculation of the square root of the hue data. Print data C, M, and Y expressed by three ink colors are output. Again,
Since no mutual interference occurs between the components and between the hues, the image data R, G, B and the print data Y, M, C
Can be independently corrected, and the conversion characteristics by the matrix operation can be flexibly changed.

According to the twenty-sixth aspect, the color conversion processing is performed for each pixel by a new matrix operation formula including a multiplication / division term using any one of the hue data (r + c), (g + m) and (b + y) as a denominator. The achromatic color data α is similarly added to the color ink data thus obtained, and print data C, M, and Y expressed by three ink colors are output. Also in this case, there is no mutual interference in the operation between the components and between the hues, so that the image data R, G, B and the print data Y,
The six hue regions of M and C can be independently corrected, and the conversion characteristics by matrix operation can be flexibly changed.

According to the image processing method of the twenty-seventh aspect, image data R, G, and B represented by three colors of red, green, and blue are further provided.
Are subjected to color conversion processing for each pixel, and print data C, M, and Y in which the ink data of the achromatic color data α are represented by three ink colors that are finely adjusted are output. In this case, there is no mutual interference in the operation between the components and the hues, so that the six hue regions of the image data R, G, B and the print data Y, M, C can be corrected independently, and Conversion characteristics by calculation can be flexibly changed.

According to the method of the twenty-eighth aspect, the print data in which the ink data of the achromatic color data α is similarly represented by three ink colors finely adjusted by a new matrix operation formula including the operation of the square root of the hue data C, M, and Y are output. In this case as well, since there is no mutual interference in the operation between each component and between the hues, the six hue regions of the image data R, G, B and the print data Y, M, C can be corrected independently, and the matrix Conversion characteristics by calculation can be flexibly changed.

According to the method of claim 29, the achromatic color data α is similarly obtained by a new matrix operation formula including a multiplication / division term having any one of the hue data (r + c), (g + m) and (b + y) as a denominator. Print data C, which is expressed by three ink colors obtained by finely adjusting the ink data of
M and Y are output. Also in this case, no mutual interference occurs between the components and the hues, so that the image data R,
The six hue regions of G and B and the print data Y, M and C can be independently corrected, and the conversion characteristics by the matrix operation can be flexibly changed.

According to the method of the thirtieth aspect, the image data R, G, B are converted into the sensor data Cin, Min, Yin.
The print data C, M, and Y are converted to the color separation data Rout, G
By substituting out and Bout respectively, C
The color separation data can be obtained from the sensor data using the filters for M, Y, and Y.

According to the image processing method of the thirty-first aspect, image data R, G, and R represented by three colors of red, green, and blue are further provided.
When color conversion processing is performed on each pixel such as B, the minimum value α of the complementary color data is added to the print data K and the residual data α−K, whereby the image data is converted into cyan, magenta, yellow, and black. Can be converted into print data composed of four inks. In addition, when the color ink data and the residual data α-K are added to output print data C, M, Y, and K represented by four ink colors, the mutual interference of the operation between each component and between the hues is obtained. Does not occur, the image data R, G, B and print data Y, M, C, K
One hue region can be corrected independently, and the conversion characteristics by matrix operation can be flexibly changed.

According to the method of the thirty-second aspect, by adding a process of dividing the minimum value α of the complementary color data into the print data K and the residual data α-K, the image data can be converted into cyan, magenta, yellow, and black. It can be converted to print data consisting of four inks. Also, the residual data α-K is similarly added to the color ink data color-converted for each pixel by a new matrix operation expression including the square root operation of the hue data, and the print data represented by four ink colors is obtained. C, M, Y, and K are output. Again,
Since no mutual interference occurs between the components and between the hues, the image data R, G, B and the print data Y, M,
The seven hue regions of C and K can be independently corrected, and the conversion characteristics by matrix operation can be flexibly changed.

According to the method of the thirty-third aspect, by adding the process of dividing the minimum value α of the complementary color data into the print data K and the residual data α-K, the image data can be converted into cyan, magenta, yellow and black. It can be converted to print data consisting of four inks. Also, the hue data (r +
c) The residual data α-K is similarly converted to the color ink data color-converted for each pixel by a new matrix operation formula including a multiplication / division term having any of (g + m) or (b + y) as a denominator. The print data C, M, Y, and K represented by the four ink colors are output. Also in this case, there is no mutual interference in the operation between the components and between the hues, so that the image data R, G, B and the print data Y,
The seven hue regions of M, C, and K can be independently corrected, and the conversion characteristics by the matrix operation can be flexibly changed.

[0464] According to the image processing method of the thirty-fourth aspect, image data R, G, B expressed in three colors of red, green and blue are further provided.
Are subjected to color conversion processing for each pixel, the ink data of achromatic data is finely adjusted by the residual data α-K, and print data C, M, Y, and K represented by four ink colors are output. In this case as well, since there is no mutual interference in the operation between the components and the hues, the seven hue regions of the image data R, G, B and the print data Y, M, C, K can be corrected independently. Further, the conversion characteristics by the matrix operation can be flexibly changed.

According to the method of claim 35, the ink data of the achromatic color data is similarly fine-tuned by the residual data α-K by the new matrix operation formula including the calculation of the square root of the hue data. Print data C, M, Y, and K to be expressed are output. Again,
Since no mutual interference occurs between the components and between the hues, the image data R, G, B and the print data Y, M,
The seven hue regions of C and K can be independently corrected, and the conversion characteristics by matrix operation can be flexibly changed.

According to the method of the thirty-sixth aspect, the residual data α− is similarly obtained by a new matrix operation formula including a multiplication / division term having any one of the hue data (r + c), (g + m) and (b + y) as a denominator. The ink data of achromatic data is finely adjusted by K, and print data C, M, Y, and K expressed by four ink colors are output. Also in this case, there is no mutual interference in the operation between the components and between the hues, so that the image data R, G, B and the print data Y,
The seven hue regions of M, C, and K can be independently corrected, and the conversion characteristics by the matrix operation can be flexibly changed.

According to the image processing apparatus of the present invention, the operated data Y is represented by using at least two of the first-order, second-order, third-order, and multiplication / division terms of the image data X. By providing means for executing a function operation expression, two or more components of a primary component, a secondary component, and a multiplication / division component can be given to the gradation characteristic. It is easy, and an arbitrary gradation characteristic can be realized only by changing several constants.

According to the image processing apparatus of the thirty-eighth aspect, the hardware scale is fixed at the time of performing the function operation for obtaining the data to be operated Y from the modification amount a1 · X · (X−a2) / (X + a3). Further, by simply changing the numerical values of a1, a2, and a3, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing apparatus of the thirty-ninth aspect, the hardware scale is fixed at the time of performing the function operation for obtaining the operated data Y from the modification coefficient 1 + a1 · (X−a2) / (X + a3). By simply changing the numerical values of a1, a2, and a3, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing apparatus of the fortieth aspect, the modification amount a1.X. (X-a2). (X-a3) / (X + a
In performing the function operation for obtaining the operation target data Y from 4), the hardware scale is fixed, and a1, a
By simply changing the numerical values of 2, a3 and a4, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing apparatus of claim 41, the modification coefficient 1 + a1 · (X−a2) · (X−a3) / (X + a
In performing the function operation for obtaining the operation target data Y from 4), the hardware scale is fixed, and a1, a
By simply changing the numerical values of 2, a3 and a4, an arbitrary gradation characteristic can be flexibly realized.

According to the image processing apparatus of claim 42, the modification amount a1.X. (X-a2) + a3.X. (X-a2).
When performing a function operation to obtain the data Y to be operated on from (X−a4) / (X + a5), the hardware scale is fixed, and further, by changing the numerical values of a1, a2, a3, a4, and a5, The gradation characteristics can be flexibly realized.

According to the image processing apparatus of the forty-third aspect, the modification coefficient 1 + a1 · (X−a2) + a3 · (X−a2) ·
When performing a function operation to obtain the data Y to be operated on from (X−a4) / (X + a5), the hardware scale is fixed, and further, by changing the numerical values of a1, a2, a3, a4, and a5, The gradation characteristics can be flexibly realized.

[0474] According to the apparatus of claim 44, the hardware scale is fixed when executing the function operation.
By changing the amount of modification to the image data by the numerical values of a1, a2, and a3, an arbitrary gradation characteristic can be realized more flexibly.

[0475] According to the apparatus of claim 45, when performing the function operation, the hardware scale is fixed.
By changing the modification coefficient of the image data by the numerical values of a1, a2, and a3, an arbitrary gradation characteristic can be realized more flexibly.

According to the device of claim 46, the hardware scale is fixed at the time of executing the function operation.
By changing the amount of modification to the image data by the numerical values of a1, a2, and a3, an arbitrary gradation characteristic can be realized more flexibly.

According to the forty-seventh aspect, when performing the function operation, the hardware scale is fixed.
By changing the modification coefficient of the image data by the numerical values of a1, a2, and a3, an arbitrary gradation characteristic can be realized more flexibly.

According to the device of claim 48, when performing the function operation, the hardware scale is fixed.
The amount of modification to the image data is determined by threshold values h, a1, a2,
By changing the values of a3, a4, and a5, arbitrary gradation characteristics can be realized more flexibly.

[0479] According to the device of claim 49, when performing the function operation, the hardware scale is fixed.
The amount of modification to the image data is determined by threshold values h, a1, a2,
An arbitrary gradation characteristic can be realized more flexibly by changing the numerical value of a3.

According to the image processing apparatus of the fiftyth aspect, the provision of the means for varying the numerical values of the constants of the respective functional expressions allows the gradation processing of any characteristic to be performed flexibly.

According to the image processing apparatus of claim 51, means for selecting image data and address data, means for switching the transfer direction of write data and read data, writable memory means, and a function arithmetic expression of the present invention Since there are provided a means for generating the write data, a means for generating the address data, and a means for performing overall control, gradation conversion of an arbitrary characteristic is performed by table conversion using a memory capacity necessary for one characteristic conversion. Can be performed, and faster conversion can be performed than when a multiplier or a divider is used.

According to the image processing apparatus of the present invention, the function operation expression for gradation conversion can be calculated by an approximate value of logarithmic operation. Therefore, it is suitable for, for example, gradation processing of color separation data in a scanner device.

According to the image processing apparatus of the present invention, achromatic data and six hue data are generated from the image data.
A color conversion process capable of independently correcting (modifying) each hue is realized by a new matrix operation expression. Therefore, the image data R, represented by three colors of red, green, and blue,
In a case where G, B, and the like are subjected to color conversion processing for each pixel and print data C, M, and Y expressed by three ink colors are output,
6 of image data R, G, B and print data Y, M, C
One hue region can be independently corrected, the conversion characteristics by matrix operation can be flexibly changed, and a large-capacity memory is not required.

According to the device of the fifty-fourth aspect, similarly, achromatic color data α is added to the color ink data color-converted for each pixel by a new matrix operation formula including the operation of the square root of the hue data. Then, print data C, M, and Y expressed by three ink colors are output. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the device of the thirty-fifth aspect, a new matrix operation formula including a multiplication / division term having any one of the hue data (r + c), (g + m), and (b + y) as a denominator allows a color to be calculated for each pixel. Similarly, achromatic color data α is added to the converted color ink data, and print data C, M, and Y expressed by three ink colors are output. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the apparatus of claim 56, image data R, G, B and the like expressed in three colors of red, green and blue are subjected to color conversion processing for each pixel, and the achromatic color data α Print data C, M, and Y represented by three ink colors whose ink data is finely adjusted are output. By finely adjusting the achromatic color, standard black, bluish black, reddish black and the like can be selected. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the apparatus of the present invention, the ink data of the achromatic color data α is similarly represented by the finely adjusted three ink colors by a new matrix operation formula including the calculation of the square root of the hue data. Print data C, M,
Y is output. By finely adjusting the achromatic color, standard black, bluish black, reddish black and the like can be selected. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

[0488] According to the device of the fifty-eighth aspect, an achromatic color is similarly obtained by a new matrix operation formula including a multiplication / division term using any of the hue data (r + c), (g + m) or (b + y) as a denominator. The print data C, M, and Y are output in which the ink data of the data α is expressed by three ink colors finely adjusted. By finely adjusting the achromatic color, standard black, bluish black, reddish black and the like can be selected. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the device of the fifty-ninth aspect, the image data R, G, B are converted into the sensor data Cin, Min, Yin
The print data C, M, and Y are converted to the color separation data Rout, G
By substituting out and Bout respectively, C
The color separation data can be obtained from the sensor data using the filters for M, Y, and Y.

According to the apparatus of claim 60, image data R, G, and R represented by three colors of red, green, and blue are further provided.
When color conversion processing is performed on each pixel such as B, the minimum value α of the complementary color data is added to the print data K and the residual data α−K, whereby the image data is converted into cyan, magenta, yellow, and black. Can be converted into print data composed of four inks. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the apparatus of the thirty-first aspect, by adding a process of dividing the minimum value α of the complementary color data into the print data K and the residual data α−K, the image data can be converted into cyan, magenta, yellow, It can be converted to print data consisting of four black inks. Also, the residual data α-K is similarly added to the color ink data color-converted for each pixel by a new matrix operation expression including the square root operation of the hue data, and the print data represented by four ink colors is obtained. C, M, Y, and K are output. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the apparatus of claim 62, by adding a process of dividing the minimum value α of the complementary color data into the print data K and the residual data α-K, the image data can be converted into cyan, magenta, yellow, It can be converted to print data consisting of four black inks. In addition, the remaining color ink data is subjected to color conversion processing for each pixel by a new matrix operation formula including a multiplication / division term having any of the hue data (r + c), (g + m) or (b + y) as a denominator. The data α-K are added, and print data C, M, Y, and K represented by four ink colors are output.
In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the apparatus of claim 63, image data R, G, B, and the like expressed in three colors of red, green, and blue are subjected to color conversion processing for each pixel, and residual data α-K The fine adjustment of the ink data of the achromatic data is performed, and print data C, M, Y, and K expressed by four ink colors are output. By finely adjusting the achromatic color, standard black, bluish black, reddish black and the like can be selected. And LS
It is easy to implement I and does not require a large capacity memory.
The color conversion can be executed by correcting two hue regions independently.

According to the 64th aspect of the present invention, the ink data of the achromatic color data is similarly fine-tuned by the residual data α-K by the new matrix operation formula including the square root operation of the hue data. Print data C, M, Y, and K represented by colors are output. By finely adjusting the achromatic color, standard black, bluish black, reddish black and the like can be selected. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the device of the 65th aspect, the residual data is similarly obtained by a new matrix operation formula including a multiplication / division term having any one of the hue data (r + c), (g + m) and (b + y) as a denominator. The ink data of the achromatic data is finely adjusted by α-K, and print data C, M, Y, and K represented by four ink colors are output. By finely adjusting the achromatic color, standard black, bluish black, reddish black and the like can be selected. In addition, it is easy to implement an LSI, and color conversion can be executed by independently correcting six hue regions without requiring a large-capacity memory.

According to the image processing apparatus of the present invention, by preparing various color conversion modes and selectively using a plurality of functions, excellent color reproducibility can be obtained.
A general-purpose color conversion function can be realized.

According to the image processing apparatus of claim 67, a general-purpose color conversion function can be realized with a small amount of arithmetic means using a memory capacity corresponding to one characteristic.

According to the image processing apparatus of claim 68, a specific processing characteristic is selected from a plurality of processing characteristics based on the characteristics of the input device, the characteristics of the output device, and the overall characteristics to be realized. Image processing can be performed on the image data. Therefore, the contrast and color reproducibility of the output image can be adjusted to an optimum state, and a hard copy image with a three-dimensional effect can be obtained. According to the image processing apparatus described in claim 69, the characteristic of the first apparatus or the characteristic with the input image data, the characteristic of the second apparatus, and the processing characteristic specified from the plurality of processing characteristics in accordance with the overall characteristic to be realized. , And optimal image processing can be performed. Also,
Since the input image data X is directly converted to the converted data Y, errors due to the conversion can be reduced. According to the image processing apparatus of claim 70, when the first device is a display device or an image reading device, the characteristics of the first device or the characteristics with the input image data, the characteristics of the second device, In addition, it is possible to select a specific processing characteristic from among a plurality of processing characteristics according to the total characteristic to be realized, and perform optimal image processing.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a gradation processing apparatus according to an embodiment of the present invention.

FIGS. 2A and 2B are diagrams illustrating input / output characteristics of the gradation processing apparatus of FIG. 1;

FIGS. 3A and 3B are diagrams illustrating other input / output characteristics of the gradation processing apparatus of FIG. 1;

FIGS. 4A and 4B are diagrams illustrating still another input / output characteristic of the gradation processing apparatus of FIG. 1;

FIG. 5 is a block diagram showing a configuration of a gradation processing apparatus according to another embodiment of the present invention.

6A and 6B are diagrams showing input / output characteristics of the gradation processing device of FIG. 5, respectively.

7A and 7B are diagrams illustrating other input / output characteristics of the gradation processing device of FIG. 5;

8A and 8B are diagrams showing still another input / output characteristic of the gradation processing device of FIG. 5;

FIG. 9 is a block diagram illustrating a configuration of a gradation processing apparatus according to a third embodiment of the present invention.

FIG. 10 is an input / output characteristic diagram of a gradation processing apparatus according to a fourth embodiment of the present invention.

FIG. 11 is a block diagram illustrating a configuration of a gradation conversion apparatus according to a fifth embodiment of the present invention.

12 is a diagram illustrating input / output characteristics of the gradation conversion device in FIG. 11;

13A and 13B are diagrams showing other input / output characteristics of the tone conversion device of FIG. 11;

FIG. 14 is a block diagram illustrating a configuration of a gradation conversion apparatus according to a sixth embodiment of the present invention.

15 is a diagram illustrating input / output characteristics of the gradation conversion device in FIG.

FIG. 16 is a block diagram illustrating a configuration of a gradation conversion apparatus according to a seventh embodiment of the present invention.

FIGS. 17A to 17C are diagrams illustrating input / output characteristics of the gradation conversion device in FIG. 16;

FIG. 18 is a block diagram illustrating a configuration of a gradation conversion apparatus according to an eighth embodiment of the present invention.

19 is a diagram showing input / output characteristics of the gradation conversion device in FIG.

FIG. 20 is a block diagram illustrating a configuration of a gradation conversion apparatus according to a ninth embodiment of the present invention.

FIG. 21 is a block diagram illustrating a configuration of a gradation processing apparatus according to Embodiment 10 of the present invention;

FIG. 22 is a block diagram illustrating a configuration of a gradation conversion apparatus according to an eleventh embodiment of the present invention.

FIG. 23 is a flowchart illustrating a gradation processing method according to a twelfth embodiment of the present invention;

FIG. 24 is a flowchart illustrating a gradation processing method that is Embodiment 13 of the present invention.

FIG. 25 is a flowchart illustrating a gradation processing method that is Embodiment 14 of the present invention;

FIG. 26 is a flowchart illustrating a gradation processing method that is Embodiment 15 of the present invention.

FIG. 27 is a flowchart illustrating a gradation processing method that is Embodiment 16 of the present invention;

FIG. 28 is a flowchart illustrating a gradation processing method that is Embodiment 17 of the present invention;

FIG. 29 is an input / output characteristic diagram of a gradation processing apparatus according to Embodiment 18 of the present invention;

FIG. 30 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 19 of the present invention.

FIG. 31 is a block diagram illustrating a configuration example of a polynomial arithmetic unit illustrated in FIG. 30.

32 is a block diagram illustrating a configuration example of a matrix calculator illustrated in FIG. 30.

FIGS. 33A to 33F are schematic diagrams of hue data used in a matrix operation expression.

FIGS. 34A to 34F are schematic diagrams of multiplication terms used in a matrix operation expression.

FIGS. 35 (A) to (C) are xy chromaticity diagrams illustrating a characteristic example in which the color conversion device of FIG. 30 is applied to a sublimation dye ink.

FIG. 36 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 20 of the present invention.

FIG. 37 is a block diagram illustrating a configuration example of a nigori operation unit illustrated in FIG. 36.

FIG. 38 is a block diagram illustrating a configuration example of an achromatic operation unit illustrated in FIG. 36.

FIG. 39 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 21 of the present invention.

FIG. 40 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 22 of the present invention.

FIG. 41 is a block diagram illustrating a configuration example of a divider illustrated in FIG. 40.

FIGS. 42A and 42B are diagrams illustrating an example of characteristics obtained by dividing achromatic data used by the color conversion apparatus of FIG. 40 by a functional expression.

FIG. 43 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 23 of the present invention.

FIG. 44 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 24 of the present invention.

FIGS. 45A to 45D are diagrams illustrating an outline of time-division calculation performed by the color conversion apparatus of FIG. 44;

FIGS. 46A to 46C are schematic diagrams illustrating differences in operation terms of a matrix operation expression in the color conversion device of FIG. 44;

FIG. 47 is a block diagram illustrating a configuration of a color conversion apparatus that is Embodiment 25 of the present invention.

FIGS. 48A to 48E are schematic diagrams illustrating differences in operation terms of a matrix operation expression in the color conversion device of FIG. 47;

FIG. 49 is a part of a flowchart showing a color conversion method which is Embodiment 26 of the present invention.

FIG. 50 is a part of a flowchart showing a color conversion method which is Embodiment 26 of the present invention;

FIG. 51 is a part of a flowchart showing a color conversion method which is Embodiment 26 of the present invention;

FIG. 52 is a part of a flowchart showing a color conversion method which is Embodiment 26 of the present invention.

FIG. 53 is a flowchart of a subroutine for executing color conversion according to the twenty-sixth embodiment.

FIG. 54 is a flowchart of another subroutine for executing color conversion according to the twenty-sixth embodiment.

FIG. 55 is a flowchart of yet another subroutine for executing color conversion according to the twenty-sixth embodiment.

FIG. 56 is a flowchart of another subroutine for executing color conversion according to the twenty-sixth embodiment.

FIG. 57 is a flowchart of yet another subroutine for executing color conversion according to the twenty-sixth embodiment.

FIG. 58 is a block diagram showing a color conversion apparatus which is Embodiment 27 in which the invention is applied to a scanner apparatus.

FIG. 59 is a block diagram illustrating a configuration of an image processing apparatus that is Embodiment 28 of the present invention.

FIG. 60 is a block diagram showing a modified configuration of the image processing apparatus that is Embodiment 28 of the present invention.

FIG. 61 is a diagram showing an example of a conventional gradation processing device.

FIG. 62 is a diagram showing another example of a conventional tone conversion device.

FIG. 63 is a block diagram illustrating an example of a conventional color conversion device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 constant generator, 2 first multiplier, 3 second multiplier, 4 divider, 5 first subtractor, 6 first adder, 7 second adder, 8 third multiplier , 9 second subtractor, 10 DFF (D-type flip-flop circuit),
11 first selector, 12 second selector, 13 third
Selector, 14 first preprocessor, 15 third multiplier, 16 second preprocessor, 17 fourth multiplier, 18
Threshold generator, 19 third preprocessor, 24 memories, 25 bidirectional buffers, 26 address generators, 2
7 conversion data generator, 28 controller, 30 complementer,
31, 32 αβ calculator, 33 hue data calculator, 3
4 Polynomial arithmetic unit, 35 Zero remover, 36, 37, 4
2, 43, 44, 51 multipliers, 38, 39, 45, 4
6 adder, 40, 41 divider, 47 Nigori operator,
48 achromatic adjuster, 49, 55 subtractor, 50 operation controller, 52 divider, 53 selector, 54 constant generator, 56 conversion controller, 57 first multiplexer, 58 second multiplexer, 59 Cumulative multiplier, 60 square root, 61
Image equipment, 62 Video equipment, 63 Gradation processing device, 64
CRT (cathode ray tube) display, 65
PDP (plasma display panel) display, 6
6 LCD (Liquid Crystal Display) display, 67 first gradation processing device, 68 second gradation processing device, 69 third gradation processing device, 70 fourth gradation processing device, 71 th gradation processing device 5 gradation processing device, 72 sixth gradation processing device, 73 seventh gradation processing device, 74 eighth gradation processing device, 75 ninth gradation processing device, 76 first gradation processing device
0 gradation processing device, 100 refresh pattern memory, 101 table select circuit, 102 RAM (random access memory), 103 control unit, 104, density table, 105 density correction table, 106 logarithmic converter, 107 adder, 108 minimum value Calculator, 109
Subtractor, 110 coefficient generator, 111 matrix calculator, 112 ROM, 113 synthesizer.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Noriko Baba, Inventor 1 Baba Zujo, Nagaokakyo-shi, Kyoto Inside Mitsubishi Electric Corporation Image Systems Development Laboratory (72) Inventor Yoshiaki Okuno 1 Baba Zhou, Nagaokakyo-shi, Kyoto Mitsubishi Denki Inc.

Claims (70)

[Claims] 1. An image processing method for outputting operated data Y by gradation operation using image data X as input, wherein at least one of a first-order, second-order, or third-order term of the image data X, and a multiplication / division term An image processing method, comprising: setting a function formula including two terms; and outputting the operated data Y based on the function formula. 2. The data to be operated Y is calculated using the image data X and constants a1, a2, and a3 as follows: Y = X + a1 · X · (X−a2) / (X + a3) (1) or Y = X · The image processing method according to claim 1, wherein {1 + a1 · (X−a2) / (X + a3)} (2). 3. An image processing method for executing a process of outputting data to be operated Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2, a
(B) calculating the difference (X−a2) and the sum (X + a3) from the image data and the constant;
(C) a step of obtaining a modification amount a1 · X · (X−a2) / (X + a3) from the image data, the difference and the sum, and the constant, and (D) an operation data Y from the image data and the modification amount.
3. The step of obtaining
The image processing method according to 1. 4. An image processing method for executing a process of outputting operated data Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2, a
(B) calculating the difference (X−a2) and the sum (X + a3) from the image data and the constant;
(C) a step of obtaining a correction coefficient 1 + a1 · (X−a2) / (X + a3) from the image data, the difference and the sum, and the constant, and (D) a step of obtaining the operand data Y from the image data and the correction coefficient. The image processing method according to claim 2, further comprising: 5. The data to be operated Y is expressed as follows: Y = X + a1 · X · (X−a2) · (X−a3) / (X + a4) using the image data X and the constants a1, a2, a3 and a4. (3) or Y = X ｛{1 + a1 ま た は (X-a2) ・ (X-a3) / (X + a4)｝ (4)} (4) . 6. An image processing method for executing, by a program, a process of outputting operated data Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2, a
(B) generating a difference (X-a2), (X-a3) and a sum (X + a) from the image data and the constant.
4C), (C) modifying amounts a1, X, (X-a2), (X) from the image data, the difference and the sum, and the constant;
6. The image processing method according to claim 5, further comprising: (a) calculating (a) / (X + a4); and (D) calculating data Y to be operated on from the image data and the modification amount. 7. An image processing method for executing, by a program, a process of outputting operated data Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2, a
(B) generating a difference (X-a2), (X-a3) and a sum (X + a) from the image data and the constant.
(C) modifying coefficient 1 + a1 · (X−a2) · from the image data, the difference and the sum, and the constant;
(X−a3) / (X + a4), (D)
6. The image processing method according to claim 5, further comprising a step of obtaining data to be operated on from the modification coefficient. 8. The data Y to be operated is calculated by using the image data X and the constants a1, a2, a3, a4, and a5 as follows: Y = X + a1.X. (X-a2) + a3.X. (X-a2 ) · (X−a4) / (X + a5) (5) or Y = X · {1 + a1 · (X−a2) + a3 · (X−a2) · (X−a4) / (X + a5)} (6) The image processing method according to claim 1, wherein: 9. An image processing method for executing, by a program, a process of outputting operated data Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2, a
(B) generating a difference (X−a2), (X−a4) and a sum (X) from the image data and the constant.
+ A5), (C) a modification amount a1.X. (X-a2) + from the image data, the difference and the sum, and the constant.
a3.X. (X-a2). (X-a4) / (X + a5)
9. The image processing method according to claim 8, further comprising the step of: (D) obtaining the operated data Y from the image data and the modification amount. 10. An image processing method for executing, by a program, a process of outputting operated data Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2,
generating a3, a4, a5, (B) obtaining a difference (X-a2), (X-a4) and a sum (X + a5) from the image data and the constant, and (C) the difference, the sum and the constant Modification coefficient 1 + a1 · (X-a2) + a3 ·
9. The method according to claim 8, further comprising: (X-a2). (X-a4) / (X + a5), and (D) a step of calculating the operated data Y from the image data and the modification coefficient. Image processing method. 11. The data to be converted Y is image data X
Using the constants a1, a2, and a3, Y = X-a1.X. (X-a2). (X-a3) (7) or Y = X..SIGMA.1-a1. (X-a2) The image processing method according to claim 1, wherein (X-a3)｝ (8) is represented. 12. An image processing method for executing a process of outputting converted data Y by a gradation operation with image data X as an input, wherein (A) constants a1, a2,
generating a3, (B) obtaining differences (Xa2) and (Xa3) from the image data and the constant,
(C) A modification amount a1 · from the image data, the difference, and the constant.
A step of obtaining X · (X−a2) · (X−a3);
12. The image processing method according to claim 11, further comprising: (D) obtaining data to be converted Y from the image data and the modification amount. 13. An image processing method for executing a process of outputting converted data Y by a gradation operation with image data X as an input by a program, wherein (A) constants a1, a2,
generating a3, (B) obtaining differences (Xa2) and (Xa3) from the image data and the constant,
(C) From the difference and the constant, the modification coefficient 1−a1 · (X−
12. The image processing method according to claim 11, further comprising: a2) obtaining (X-a3); and (D) obtaining converted data Y by multiplying the image data by the modification coefficient. 14. The data to be converted Y
Using the constants a2, a3, a4, and a5, Y = XX− (X−a3) · {a4 · (X−a2) + a5 · | X−a2 |} (9) or Y = The image processing method according to claim 1, wherein X · [1− (X−a3) · {a4 · (X−a2) + a5 · | X−a2 |}] (10) . 15. An image processing method for executing a process of outputting converted data Y by a gradation operation with image data X as an input, wherein (A) constants a2, a3,
generating a4, a5, (B) obtaining differences (Xa2), (Xa3) and absolute value | Xa2 | from the image data and the constant, (C) image data, the constant, From the difference and the absolute value, a modification amount X · (X
−a3) · ｛a4 · (X−a2) + a5 · | X−a2
15. The image processing method according to claim 14, further comprising: a step of obtaining |｝; and (D) a step of obtaining converted data Y from the image data and the amount of modification. 16. An image processing method for executing a process of outputting converted data Y by a gradation operation using image data X as an input, wherein (A) constants a2, a3,
generating a4, a5; (B) obtaining a difference (X-a2), (X-a3) and an absolute value | X-a2 | from the image data and the constant; (C) calculating the difference between the constant and the difference. From the absolute value, the modification coefficient 1− (X−a3) · ｛a4
15. (X-a2) + a5. | X-a2 |｝, and (D) a step of obtaining transformed data Y by multiplying the image data by the modification coefficient. Image processing method. 17. The method according to claim 1, wherein the data to be converted Y is image data X
When X ≦ h using the threshold h and the constants a1, a2, a3, a4, and a5, Y = X−a1 · X · (X−h) · (X−a3) (11) X> 2. The image processing method according to claim 1, wherein when h, Y = X−a2 · (X−h) · (X−a4) · (X−a5) (12) 18. An image processing method for executing a process of outputting converted data Y by gradation operation with image data X as an input, wherein (A) threshold value h and constants a1, a2, a3, a4 Generating a, a5,
(B) The difference between the image data, the threshold value, and the constant (X
-H), (Xa3), (Xa4), (Xa5), (C) comparing the image data with the threshold, and (D) comparing the image data. From the constants and the difference, when X ≦ h, a1 · X · (X−h) · (X−a3), and when X> h, a2 · (X−h) · (X −a4) ・ (X
18. The image processing method according to claim 17, further comprising: (a) determining a modification amount; and (E) determining conversion target data Y from the image data and the modification amount. 19. An image processing method for outputting converted data Y by a gradation operation with image data X as input, wherein the converted data Y uses image data X, threshold value h, and constants a1, a2, and a3. When X ≦ h, Y = X−a1 · X · (X−h) (13) When X> h, Y = X−a2 · (X−h) · (X−a3) (X-a3) 14. The image processing method according to claim 1, wherein the image processing method is expressed as: 20. In an image processing method for executing a process of outputting converted data Y by a gradation operation with image data X as an input, (A) generating a threshold value h and constants a1, a2 and a3 (B) obtaining differences (Xh) and (Xa3) from the image data and the threshold and the constant; (C) comparing the image data with the threshold. (D) According to the comparison result of the image data, from the constant and the difference, when X ≦ h, a1 · X · (X−h), and when X> h,
20. The apparatus according to claim 19, further comprising: a step of calculating a modification amount of a2. (Xh). (X-a3); and (E) a step of calculating conversion target data Y from image data and the modification amount. Image processing method. 21. An image processing method for outputting converted data Y by a gradation operation with image data X as an input, wherein a plurality of gradations are changed by changing a constant or a threshold value unique to each functional expression. 20. The image processing method according to claim 2, wherein the conversion characteristic is realized. 22. In an image processing method for executing a process of outputting converted data Y by gradation operation with image data X as an input, changing a constant or a threshold value unique to each function expression. 4. The method according to claim 3, further comprising the step of: realizing a plurality of gradation conversion characteristics.
Claim 4, Claim 6, Claim 7, Claim 9, Claim 1
0, Claim 12, Claim 13, Claim 15, Claim 1
The image processing method according to any one of claims 18 to 20. 23. An image processing method for outputting operated data Y by gradation operation with image data X as input, comprising: setting a function expression including a logarithmic term of the image data X; Outputting the data Y to be operated. 24. Color conversion processing of image data R, G, and B represented by three colors of red, green, and blue for each pixel to obtain cyan,
In an image processing method for outputting print data C, M, and Y expressed by three ink colors of magenta and yellow,
(A) Complementary color data Ci, M from image data R, G, B
i, Yi; (B) finding the following minimum value α and maximum value β from the complementary color data; α = MIN
(Ci, Mi, Yi), β = MAX (Ci, Mi, Y
i) (C) a step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = β -Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3; j = 1 to 3 (Fij) is i = 1 to 3; j = 1 to 12 (E) By a matrix operation according to the following equation (15) A step of obtaining print data C, M, and Y; An image processing method comprising: 25. The image processing method according to claim 24, wherein the matrix operation in the step (E) is executed by the following equation (16) instead of the equation (15). (Equation 2) 26. The matrix operation of the step (E) is replaced by the following equation (17) instead of the equation (15), or the (r + c) term of the equation (17) is a (g + m) term or a (b + y) term. 25. The image processing method according to claim 24, wherein the image processing method is executed by replacing the above. (Equation 3) 27. Color conversion processing of image data R, G, and B represented by three colors of red, green, and blue for each pixel to obtain cyan,
In an image processing method for outputting print data C, M, and Y expressed by three ink colors of magenta and yellow,
(A) Complementary color data Ci, M from image data R, G, B
i, Yi, (B) a step of obtaining the following minimum value α and maximum value β from the complementary color data, α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3; j = 1 to 3 (Fij) is i = 1 to 3; j = 1 to 14 (E) The matrix operation expression of the following expression (18) Calculating print data C, M, and Y by An image processing method comprising: 28. The image processing method according to claim 27, wherein the matrix operation of the step (E) is executed by the following equation (19) instead of the equation (18). (Equation 5) 29. The matrix operation of the step (E) is replaced with the following equation (20) instead of the equation (18), or the (r + c) term of the equation (20) is replaced with a (g + m) term or a (b + y) term. 28. The image processing method according to claim 27, wherein the image processing method is executed by replacing the above. (Equation 6) 30. An image processing method for subjecting sensor data Rin, Gin, Bin represented by three colors of red, green, and blue to color conversion processing for each pixel and outputting color separation data Rout, Gout, Bout. The image data C, M, Y in the step (A) or the complementary color data C to be generated
i, Mi, Yi are converted to sensor data Rin, Gin, Bin
And in the step (E), the color separation data R
The image processing method according to any one of claims 24, 25, 26, 27, 28, or 29, wherein out, Gout, and Bout are obtained. 31. Image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel,
In an image processing method for outputting print data C, M, Y, and K represented by four ink colors of magenta, yellow, and black, (A) generating complementary color data Ci, Mi, and Yi from image data R, G, and B (B) a step of obtaining the following minimum value α and maximum value β from the complementary color data: α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) a step of dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Ei
(Eij), i = 1 to 3, j = 1 to 3 (Fij), i = 1 to 3, j = 1 to 12 (F) The following formula (F) 21) a step of obtaining print data C, M, Y by a matrix operation according to 21), An image processing method comprising: 32. The image processing method according to claim 31, wherein the matrix operation in the step (F) is executed by the following equation (22) instead of the equation (21). (Equation 8) 33. The matrix operation of the step (F) is replaced by the following equation (23) instead of the equation (21), or the (r + c) term of the equation (23) is replaced with a (g + m) term or a (b + y) term. 32. The image processing method according to claim 31, wherein the image processing method is executed by replacing the above. (Equation 9) 34. Image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel to obtain cyan,
In an image processing method for outputting print data C, M, Y, and K represented by four ink colors of magenta, yellow, and black, (A) generating complementary color data Ci, Mi, and Yi from image data R, G, and B (B) a step of obtaining the following minimum value α and maximum value β from the complementary color data: α = MIN (Ci, Mi, Yi), β = MAX (Ci,
Mi, Yi) (C) A step of generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum value and the maximum value: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) a step of dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Ei
(Eij), i = 1 to 3, j = 1 to 3 (Fij), i = 1 to 3, j = 1 to 14 (F) The following equation (F) 24) a step of obtaining the print data C, M, Y by the matrix operation formula of An image processing method comprising: 35. The image processing method according to claim 34, wherein the matrix operation in the step (F) is executed by the following equation (25) instead of the equation (24). [Equation 11] 36. The matrix operation of the step (F) is replaced with the following equation (26) instead of the equation (24), or the (r + c) term of the equation (26) is replaced with a (g + m) term or a (b + y) term. 35. The image processing method according to claim 34, wherein the image processing method is executed by replacing the image processing. (Equation 12) 37. An image processing apparatus for outputting operated data Y by a gradation operation with image data X as an input, wherein at least one of a first-order term, a second-order term, or a third-order term, and a multiplication / division term of the image data X is provided. An image processing apparatus comprising: means for setting a function expression including two terms; and means for outputting the operated data Y based on the function expression. 38. An image processing apparatus which outputs data Y to be operated by a gradation operation with image data X as input, wherein (A) means for generating constants a1, a2 and a3;
(B) means for calculating the difference (X-a2) and the sum (X + a3) from the image data and the constant; (C) the modification amount a1.X. (X-a2) / from the image data, the difference and the sum and the constant.
38. The image processing apparatus according to claim 37, further comprising: means for obtaining (X + a3); and (D) means for obtaining data Y to be operated on from image data and the amount of modification. 39. An image processing apparatus which outputs data to be operated Y by gradation operation with image data X as input, wherein (A) means for generating constants a1, a2, a3,
(B) means for calculating the difference (X-a2) and the sum (X + a3) from the image data and the constant; (C) the correction coefficient 1 + a1. (X-a2) from the image data, the difference and the sum and the constant.
38. The image processing apparatus according to claim 37, further comprising: means for calculating / (X + a3); and (D) means for calculating data Y to be operated on from image data and the modification coefficient. 40. An image processing apparatus which outputs data to be operated Y by gradation operation with image data X as input, (A) means for generating constants a1, a2, a3, a4; The difference (X-a2) from the constant,
Means for calculating (X-a3) and the sum (X + a4); (C) a modification amount a1 · X from the image data, the difference and the sum, and the constant;
4. A device for calculating (X-a2). (X-a3) / (X + a4), and (D) for calculating data Y to be operated on from image data and the modification amount.
8. The image processing device according to 7. 41. An image processing apparatus which outputs data to be operated Y by gradation operation with image data X as input, wherein (A) means for generating constants a1, a2, a3, a4; The difference (X-a2) from the constant,
Means for calculating (X-a3) and the sum (X + a4); (C) modifying coefficient 1 + a1. (X-a) from the difference and the sum and the constant;
2) means for determining (X-a3) / (X + a4),
38. The image processing apparatus according to claim 37, further comprising: (D) means for calculating the operated data Y from the image data and the modification coefficient. 42. An image processing apparatus which outputs data Y to be operated by a gradation operation with image data X as an input, wherein (A) means for generating constants a1, a2, a3, a4, a5; The difference between the data and the constant (X−a
2) means for calculating the sum (X + a5) with (X-a4),
(C) From the image data, the difference and the sum, and the constant, the modification amount a1 · X · (X−a2) + a3 · (X−a2) · (X−
38. The image processing apparatus according to claim 37, further comprising: means for calculating a4) / (X + a5); and (D) means for calculating data to be operated Y from image data and the amount of modification. 43. An image processing apparatus which outputs data Y to be operated by a gradation operation with image data X as input, (A) means for generating constants a1, a2, a3, a4, a5, (B) image The difference between the data and the constant (X−a
2) means for calculating the sum (X + a5) with (X-a4),
(C) From the difference and the sum and the constant, a modification coefficient 1 + a1 ·
(X-a2) + a3. (X-a2). (X-a4) /
38. The image processing apparatus according to claim 37, further comprising: means for obtaining (X + a5), and (D) means for obtaining data Y to be operated on from image data and the modification coefficient. 44. An image processing apparatus for outputting converted data Y by a gradation operation with image data X as input, wherein (A) means for generating constants a1, a2, a3,
(B) The difference (X-a2), (X
(C) a modification amount a1 · X · (X−a2) · (X−a) from the image data, the difference and the constant.
38. The image processing apparatus according to claim 37, further comprising: means for obtaining 3); and (D) means for obtaining converted data Y from the image data and the modification amount. 45. An image processing apparatus for outputting converted data Y by a gradation operation with image data X as input, wherein (A) means for generating constants a1, a2 and a3,
(B) The difference (X-a2), (X
(C) means for determining a modification coefficient 1-a1 · (X−a2) · (X−a3) from the difference and the constant, and (D) multiplication of image data and the modification coefficient. 38. The image processing apparatus according to claim 37, further comprising: means for obtaining conversion data Y. 46. An image processing apparatus for outputting converted data Y by a gradation operation with image data X as input, wherein (A) means for generating constants a2, a3, a4, a5; The difference from the above constant (X-a2),
Means for determining (X-a3) and the absolute value | X-a2 |
(C) A modification amount X · (X−a3) · ｛a4 · (X−a2) + a5 from the image data, the constant, the difference, and the absolute value.
38. The image processing apparatus according to claim 37, further comprising: means for obtaining .multidot..times..times..times..times..times..times..times..times..times..times..times..times..times..times..times..times. 47. An image processing apparatus for outputting converted data Y by a gradation operation with image data X as input, wherein (A) means for generating constants a2, a3, a4, a5; The difference from the above constant (X-a2),
Means for determining (X-a3) and the absolute value | X-a2 |
(C) From the constant, the difference, and the absolute value, a modification coefficient 1− (X−a3) · ｛a4 · (X−a2) + a5 · | X−a
38. The image processing apparatus according to claim 37, further comprising: means for obtaining 2 |｝, and (D) means for obtaining data Y to be converted by multiplying the image data by the modification coefficient. 48. An image processing apparatus for outputting converted data Y by a gradation operation with image data X as input, wherein (A) threshold value h and constants a1, a2, a3, a4
means for generating a5, (B) differences (Xh), (Xa3), (Xa) from the image data and the threshold value and the constant.
4), means for obtaining (X-a5), (C) means for comparing the magnitude of the threshold with the image data, and (D) X from the constant and the difference according to the comparison result of the image data. ≤
When h, a1 · X · (X−h) · (X−a3), X>
When h, a2ａ (Xh) ・ (Xa4) ・ (Xa
38. The image processing apparatus according to claim 37, further comprising: (5) a step of obtaining a modification amount; and (E) means for obtaining conversion target data Y from the image data and the modification amount. 49. An image processing apparatus for outputting converted data Y by a gradation operation with image data X as input, wherein (A) means for generating a threshold value h and constants a1, a2, and a3, and (B) Means for determining the difference (Xh), (Xa3) from the image data, the threshold value, and the constant;
(C) means for comparing the magnitude of the threshold with the image data; (D) the constant according to the comparison result of the image data;
From the above difference, when X ≦ h, a1 · X · (X−
h), when X> h, a2 · (X−h) · (X−a3)
38. The image processing apparatus according to claim 37, further comprising: a step of obtaining a modification amount; and (E) means for obtaining data to be converted Y from the image data and the modification amount. 50. An image processing apparatus for outputting converted data Y by gradation operation with image data X as input, comprising means for changing a constant or a threshold value unique to each function expression, 38, 39, 40, 41, 42, 43, 44, 45, 46, and 46, wherein gradation conversion characteristics are realized. The image processing device according to any one of claims 47, 48, or 49. 51. An image processing apparatus which outputs converted data Y by table conversion of image data X,
(A) means for selecting image data and address data,
(B) means for switching the transfer direction of write data and read data, (C) writable memory means,
(D) means for generating write data by a function operation,
An image processing apparatus comprising: (E) means for generating the address data; and (F) means for controlling each of the operations (A) to (E). 52. An image processing apparatus which outputs data to be operated Y by a gradation operation with image data X as input, means for setting a function expression including a logarithmic term of the image data X, based on the function expression. Means for outputting the data Y to be operated. 53. Image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel to obtain cyan,
In an image processing apparatus that outputs print data C, M, and Y expressed by three ink colors of magenta and yellow,
(A) Complementary color data Ci, M from image data R, G, B
means for generating i, Yi, (B) means for obtaining the following minimum value α and maximum value β from complementary color data, α = MIN (Ci, Mi, Yi), β = MAX (Ci,
(Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3, j = 1 to 3 (Fij) is i = 1 to 3 and j = 1 to 12 (E) The matrix operation expression of the following expression (15) Means for obtaining print data C, M, and Y by An image processing apparatus comprising: 54. The image processing apparatus according to claim 53, wherein the matrix operation of said means (E) is executed by the following equation (16) instead of equation (15). [Equation 14] 55. The matrix operation of the means (E) is replaced by the following equation (17) instead of the equation (15), or the (r + c) term of the equation (17) is replaced by the (g + m) term or the (b)
54. The image processing apparatus according to claim 53, wherein the image processing is executed by the one replaced with the term + y). (Equation 15) 56. Image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel,
In an image processing apparatus that outputs print data C, M, and Y expressed by three ink colors of magenta and yellow,
(A) Complementary color data Ci, M from image data R, G, B
means for generating i, Yi, (B) means for obtaining the following minimum value α and maximum value β from complementary color data, α = MIN (Ci, Mi, Yi), β = MAX (Ci,
(Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) Predetermined matrix coefficients (Eij) and (Fij)
(Eij) is i = 1 to 3; j = 1 to 3 (Fij) is i = 1 to 3; j = 1 to 14 (E) The matrix operation expression of the following expression (18) Means for obtaining print data C, M, and Y by An image processing apparatus comprising: 57. The image processing apparatus according to claim 56, wherein the matrix operation of said means (E) is executed by the following expression (19) instead of expression (18). [Equation 17] 58. The matrix operation of the means (E) is replaced by the following equation (20) instead of the equation (18), or the (r + c) term of the equation (20) is replaced by the (g + m) term or the (b)
57. The image processing apparatus according to claim 56, wherein the image processing is executed by the one replaced with the term + y). (Equation 18) 59. An image processing apparatus for performing color conversion processing on sensor data Rin, Gin, Bin expressed in three colors of red, green, and blue for each pixel and outputting color separation data Rout, Gout, Bout. The image data C, M, Y of the means (A) or the complementary color data Ci, M to be generated
i, Yi are replaced by sensor data Rin, Gin, Bin, and the color separation data Rout, G
The image processing apparatus according to any one of claims 53, 54, 55, 56, 57, or 58, wherein out and Bout are obtained. 60. Color conversion processing of image data R, G, and B expressed by three colors of red, green, and blue for each pixel to obtain cyan,
(A) Complementary color data Ci, Mi, and Yi are generated from image data R, G, and B in an image processing apparatus that outputs print data C, M, Y, and K represented by four ink colors of magenta, yellow, and black. Means for calculating the following minimum value α and maximum value β from the complementary color data: α = MIN (Ci, Mi, Yi), β = MAX (Ci,
(Mi, Yi) (C) Means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = Β-Yi y = Yi-α, m = Mi-α, c = Ci-α (D) means for dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient ( Eij)
(Eij) is i = 1 to 3, j = 1 to 3 (Fij) is i = 1 to 3, j = 1 to 12 (F) The following equation (21) Means for obtaining the print data C, M, Y by the matrix operation formula of An image processing apparatus comprising: 61. The image processing apparatus according to claim 60, wherein the matrix operation of said means (F) is executed by the following equation (22) instead of equation (21). (Equation 20) 62. The matrix operation of the means (F) is replaced by the following equation (23) instead of the equation (21), or the (r + c) term of the equation (23) is replaced by the (g + m) term or the (b)
61. The image processing apparatus according to claim 60, wherein the image processing is executed by the one replaced with the term + y). (Equation 21) 63. Image data R, G, and B represented by three colors of red, green, and blue are subjected to color conversion processing for each pixel,
(A) Complementary color data Ci, Mi, and Yi are generated from image data R, G, and B in an image processing apparatus that outputs print data C, M, Y, and K represented by four ink colors of magenta, yellow, and black. (B) means for calculating the following minimum value α and maximum value β from the complementary color data, α = MI
N (Ci, Mi, Yi), β = MAX (Ci, Mi, Y
i) (C) means for generating the following hue data r, g, b, y, m, c from the complementary color data and the minimum and maximum values: r = β-Ci, g = β-Mi, b = β -Yi y = Yi-α, m = Mi-α, c = Ci-α (D) means for dividing the minimum value α into print data K and residual data α-K, (E) a predetermined matrix coefficient (Eij)
(Eij) is i = 1 to 3, j = 1 to 3 (Fij) is i = 1 to 3, j = 1 to 14 (F) The following equation (24) Means for obtaining the print data C, M, Y by the matrix operation formula of An image processing apparatus comprising: 64. The image processing apparatus according to claim 63, wherein the matrix operation of said means (F) is executed by the following equation (25) instead of equation (24). (Equation 23) 65. The matrix operation of the means (F) is replaced by the following equation (26) instead of the equation (24), or the (r + c) term of the equation (26) is replaced by the (g + m) term or the (b)
64. The image processing apparatus according to claim 63, wherein the image processing is executed by the one replaced with the term + y). (Equation 24) 66. An image processing apparatus that performs color conversion processing on image data R, G, and B represented by three colors of red, green, and blue for each pixel and outputs print data. Means for selecting the color conversion processing to be either three-color conversion or four-color conversion, (B) means for selecting use or non-use of the nigori removal function in the color conversion processing, and (C) fine adjustment function for achromatic color components Means of choosing to use or not use
(D) means for selecting the setting of a constant corresponding to the fine adjustment function, (E) means for selecting the setting of the constant corresponding to the dividing function, and (F) selection of the setting of the operation coefficient corresponding to a plurality of ink sets. An image processing apparatus, comprising: at least one selecting means. 67. An image processing apparatus that performs color conversion processing on image data for each pixel and outputs print data, display data, color separation data, or other types of image data.
(A) Image data R, represented by three colors of red, green, and blue
Means for converting G and B into print data; (B) means for converting image data R, G and B expressed in three colors of red, green and blue into display data; and (C) image data from the sensor. Means for converting color-separated data or image data R, G, and B represented by three colors of red, green, and blue; (D) means for converting first-type image data into second-type image data ,
(E) means for converting the first type of image data for printing into the second type of image data for printing; (F) converting the first type of image data for color separation into the second type of color Means for converting into image data for separation, (G) unifying or matching color reproduction characteristics in a combination of at least three types of data among color separation data, image data, print data and display data. An image processing apparatus, comprising: at least one conversion unit. 68. An image processing apparatus which selects a specific processing characteristic from among a plurality of processing characteristics, performs image processing on image data, and outputs data to be operated Y, the characteristics of an input device and the characteristics of an output device. Means for selecting the processing characteristics based on, a conversion function formula according to the selected processing characteristics,
Means for changing and setting numerical values of various constants of the conversion function expression. 69. An input image data X which is used as an input of a selected first device or output from the first device, and is processed as an input of a selected second device. In the image processing apparatus for generating converted data Y to be used, each of which corresponds to a different combination of the first device and the second device, and directly converts the input image data X into the converted data Y Memory means for storing a plurality of processing characteristics of
Selecting means for selecting one of the plurality of processing characteristics stored in the memory means in accordance with the apparatus and the second apparatus; and selecting the single processing property in accordance with the selecting means. Means for changing and setting one of a conversion function and a constant for a single-step conversion between the input image data X and the converted data Y based on the input image data X and the converted data Y. 70. The image processing device according to claim 69, wherein the first device is a display device or an image reading device.