KR102061222B1 - Image processing apparatus and image processing method - Google Patents

Abstract

The method includes receiving color image data and gloss image data of an image, converting the color image data into a first printing discrepancy signal indicating a usage amount of a dark printing material having a relatively high density, and the first printing discretion signal Generating a second print quantity signal for exchanging the usage amount corresponding to the gloss image data with the usage amount corresponding to the light printing material having a relatively low density, and the second printing amount signal Converting the path decomposition data corresponding to each print scan of the image generating apparatus, and halftone processing on the path decomposition data to generate a print signal indicating an on-dot print position for each of the dark printing material and the light printing material. To overlap the on-dot of the light printing material in the printing scan of the image generating apparatus. Which includes generating the write signal.

Description

Image processing apparatus and image processing method {IMAGE PROCESSING APPARATUS AND IMAGE PROCESSING METHOD}

TECHNICAL FIELD The present invention generally relates to an image processing apparatus and an image processing method, and more particularly, to the control of gloss of an image to be generated.

When a dye ink using a dye which is easy to dissolve in water is used for the colorant, the colorant in the solvent penetrates into the fibers of the print medium, and the surface shape of the print medium is maintained even after the image is generated, and the gloss of the print medium itself is printed. It is maintained as the gloss of the image. However, dye molecules are easy to decompose by light, and printed images using dye inks tend to fade. In addition, when the printed matter using the dye ink is wet with water, bleeding occurs in the printed image because the dye molecules penetrating into the fiber dissolve in water.

In order to solve the problem of these dye inks, recently, the pigment ink using the pigment as a coloring material is used for image generation. Unlike the dyes present as molecules in the solvent, since the pigments are present in the solvent as particles having a size of several 10 nm to several micrometers, the use of the pigment ink makes it possible to obtain printed materials having high weather resistance. Although the pigment is hard to penetrate into the printing medium, it adheres to the surface of the printing medium and forms irregularities on the surface of the printing image, and the gloss of the printed matter using the pigment ink is different from the gloss of the printing medium itself. In addition, due to the properties of the resin used in the pigment ink and the pigment itself, the surface reflectance of the printed image using the pigment ink becomes larger than the printed image using the dye ink.

Moreover, the technique which acquires a decorative effect using the difference of gloss in printed matter is developed. For example, Japanese Laid-Open Patent Publication No. 2002-331708 discloses an invention in which the gloss is changed for each area or for each object to obtain a decorative effect. In recent years, the technique which tries to acquire a decorative effect by using the difference of gloss also in the printed matter using pigment ink is developed.

According to the technique described in Japanese Patent Laid-Open No. 2002-331708, based on the glossiness set for each object, the amount of transparent toner that is a gloss material is determined to obtain desired gloss. However, the control range of gloss is limited to the range which can be controlled only by the usage-amount of a gloss material. For example, glossiness cannot be controlled at all in the region where no gloss material is used.

Moreover, as a technique for controlling gloss, although not intended to obtain a decorative effect, Japanese Laid-Open Patent Publication No. 2010-284951 discloses printing of ink at the same position in a relatively high-gloss area of high gloss, thereby printing the surface of a printed image. Disclosed is an invention in which unevenness is increased to decrease gloss. However, according to this method, control such as increasing the gloss of the low-definition region, which tends to be relatively low, cannot be performed.

As described above, in the printed matter using the pigment ink, even when the decorative effect is to be obtained by using the difference in glossiness, a sufficient decorative effect cannot be obtained due to the limitation of the control range of the gloss.

Aspects of the present invention provide gloss control in printed matter.

The aspect of this invention is equipped with the following structures.

An image processing apparatus includes: an input unit configured to receive color image data and gloss image data of an image to be generated, and a first printing material amount indicating a usage amount of a dark print material having a relatively high density of the color image data; Among the usage amounts of the first color separation unit configured to convert the signal and the dark printing material indicated by the first print material amount signal, the usage amount corresponding to the gloss image data is applied to the light printing material having a relatively low density. A second color separation unit configured to generate a second printing discretion signal to be exchanged for a corresponding usage amount, a path separation unit configured to convert the second printing discretionary signal into path decomposition data corresponding to each print scan of the image generating apparatus; For each of the dark print material and the light print material, a print signal indicating a print position of on-dots is generated. Subjected to a halftone processing with respect to the decomposition pass data to, and a halftone processing unit configured to generate the print signals to generate the light-on-dot printing material overlapping in the printing scan of the image generating device.

The image processing apparatus includes an input unit configured to receive color image data and gloss image data of an image to be generated, and a feature printing material which reproduces the color image data in a usage amount of the basic color printing material and a color different from the basic color printing material. The first color separation unit configured to convert the first printing quantity signal indicating the usage amount and the usage amount corresponding to the gloss image data among the usage amounts of the feature printing material indicated by the first printing amount signal correspond to the characteristic printing material. A second color separation unit configured to generate a second print quantity signal for exchanging the usage amount corresponding to a plurality of basic color printing materials, and converting the second print quantity signal into path decomposition data corresponding to each print scan of the image generating apparatus; And a print path of on-dot for each of said primary color printing material and said characteristic printing material, Performing halftone processing on the path decomposition data to generate an output printing signal to generate overlapping on-dots of the plurality of primary color printing materials corresponding to the feature printing material in a print scan of the image generating apparatus; And a halftone processing unit configured to generate a print signal.

The image processing method includes receiving color image data and gloss image data of an image to be generated, converting the color image data into a first printing discretion signal indicating a usage amount of a dark printing material having a relatively high density, and Generating a second printing quantity signal in which the usage amount corresponding to the gloss image data is replaced with the usage amount corresponding to the light printing material having a relatively low density among the usage amounts of the dark printing material indicated by the printing quantity value signal; 2 converting the print quantity signal into path decomposition data corresponding to each print scan of the image generating apparatus, and generating the print signal representing the printing position on-dot for each of the dark printing material and the light printing material; Halftone processing is performed on the data, and the light printing material is used in the printing scan of the image generating apparatus. To generate a superposition of the dot-on includes generating the printing signal.

The image processing method is characterized by receiving color image data and gloss image data of an image to be generated, and using the color image data as the amount of primary color printing material and the amount of feature printing material for reproducing a color different from the primary color printing material. Converting into a first printing quantity signal and a usage amount corresponding to the gloss image data among the usage amounts of the feature printing material indicated by the first printing material signal correspond to a plurality of basic color printing materials corresponding to the feature printing material. Generating a second print quantity signal to be exchanged for the usage amount, converting the second print quantity signal to path decomposition data corresponding to each print scan of the image generating apparatus, and printing the primary color printing material and the feature printing material. Each time, halftone processing is performed on the path decomposition data to generate a print signal indicating a print position on the dot. And includes in the printing scan of the image generation device to generate the print signals to generate a superposition of the plurality of basic color printed material on a dot corresponding to the printing material characteristic.

According to an exemplary aspect of the present invention, it is possible to control the gloss of printed matter. For example, the gloss control range of a printed matter is extended, and a high decorative effect can be given by a printed matter.

Further aspects of the invention will be apparent from the following exemplary embodiments (with reference to the attached drawings).

1A, 1B, 1C, 1D, 1E, 1F, and 1G are diagrams schematically showing a state in which a print material of pigment is laminated on a printing medium.
Fig. 2 is a block diagram showing a configuration example of the image processing apparatus of the first embodiment.
3 is a diagram illustrating an example of a color separation table referred to by the first color separation processing unit.
4 is a block diagram showing an example of the configuration of an information processing apparatus.
5 is a flowchart for explaining processing for generating image generation data by the image processing apparatus.
6 is a diagram illustrating an example of a gloss control table referenced by the second color separation processing unit.
7A, 7B, and 7C are diagrams for describing path decomposition processing.
8A, 8B, and 8C are diagrams showing an example of a 4x4 dither matrix for halftone processing for quantizing path decomposition data of a K ″ signal into a 1-bit drive signal.
9 is a diagram showing a halftone processing result of path decomposition data having a K ″ value.
10A and 10B are diagrams for describing halftone processing of path decomposition data having a Gy ″ value.
11 is a block diagram showing an example of the configuration of the image processing apparatus of the second embodiment.
12A and 12B are views for explaining gloss control conversion and path decomposition processing.
Fig. 13 is a diagram showing a halftone processing result of the path decomposition data of the R ″ value.
FIG. 14 is a diagram showing a halftone processing result of path decomposition data having a Y "M" value.
15 is a block diagram showing a configuration example of an image processing apparatus of a third embodiment.
16A and 16B are diagrams illustrating the determination of the CL value and the path decomposition process.
17A and 17B are diagrams for describing halftone processing.
18 is a flowchart for explaining processing for generating image generation data by the image processing apparatus of the third embodiment.
19 is a block diagram showing a configuration example of an image processing apparatus of a fourth embodiment.
20A and 12B are views for explaining gloss control conversion and path decomposition processing.
21A and 12B are diagrams illustrating halftone processing of a Gy printing material.
22A and 22B are views for explaining halftone processing of the Lgy printing material.
Fig. 23 is a diagram showing the final dot layout of the BK printing material.

Hereinafter, an image processing apparatus and an image processing method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In addition, an Example does not limit this invention to a claim, and all the combinations of the structure demonstrated in an Example are not necessarily essential to the solution of this invention.

[summary]

1A, 1B, 1C, 1D, 1E, 1F, and 1G schematically show a state in which a printing material of pigment is laminated on a printing medium. FIG. 1A shows a state in which an image is generated by the printing material of black K in the entire area of the predetermined region. In the present embodiment, "area" represents the minimum unit in which dot on / off can be controlled.

FIG. 1B shows a state in which an image is generated by the combination of a K printing material and a Gly printing material. The reproduced color is as shown in Fig. 1A. In FIG. 1B, one layer of K printing material is formed in one area, while another layer of Gy printing material is laminated in another area. That is, as shown in Figs. 1A and 1B, the unevenness of the image surface of the predetermined area can be changed while reproducing the same color depending on the printing material used, the combination of the printing material, the amount of printing material used, and the stacking state of the printing material. .

Since the printing material itself has irregularities and the dot shape is almost circular when viewed from above, in the case shown in Fig. 1A, the surface of the image shown in Fig. 1A is not completely smooth, but relatively smooth. On the other hand, when shown in FIG. 1B, the thickness of the printing material layer in one area is different from the printing material layer in another area, and smoothness falls compared with the case shown in FIG. 1A. That is, the image shown in FIG. 1B has the same color as the image shown in FIG. 1A, but has a lower gloss than the image shown in FIG. 1A.

That is, the lower the gloss indicated by the gloss signal, the more dense printing material (hereinafter dark printing material) is replaced with the relatively less dense printing material (hereinafter light printing material), and the light printing material is overlapped with the color. By reproducing increases the unevenness of the surface of the image. This makes it possible to control the gloss.

Hereinafter, the lamination state of the printing material indicates in what order the printing material of what color and the printing material of what color are laminated. In addition, below, the coloring of the 1st printing material (for example, K printing material) of n layer (n is natural number), and the 2nd printing material of m layer (m is natural number, n <m) (for example, And a combination of printing materials that can be considered to have the same color development.

Moreover, it is also possible to use the 3rd printing material (for example, Light Gray (Lgy) printing material) with a density lower than a 1st and 2nd printing material. Of course, not only the combination of a black printing material but a combination of a cyan (C) printing material, a light cyan (Lc) printing material, and a magenta (M) printing material and a soft magenta (Lm) printing material is also available. Hereinafter, in order to simplify description, it demonstrates centering on the combination of K printing material and Gy printing material.

[First Embodiment]

[Configuration of the device]

2 is a block diagram showing an example of the configuration of the image processing apparatus 12 of the first embodiment. In FIG. 2, the input unit 101 displays color image data RGB indicating the color of each pixel of the image to be printed, and glossy image data GI indicating the gloss clarity of each pixel of the image to be printed. It receives from the information processing apparatus 11.

The input unit 101 performs resolution conversion in which the resolutions of the input data (color image data RGB and gloss image data GI) and the print resolution of the image generating device 13 are different, to match the resolutions of both. When the resolution of the input data is 600 ppi, the print resolution is 2400 dpi in the main scanning direction, and 1200 dpi in the sub-scanning direction, the input unit 101 converts the input data by, for example, resolution conversion such as a bicubic method. The data is converted into data of 2400 dpi in the main scanning direction and 1200 dpi in the sub scanning direction.

The color image data RGB and the gloss image data GI are data created, edited or processed by various applications running on the information processing apparatus 11 which is a computer device, and the color image data RGB is sRGB data, for example. The color image data RGB and the gloss image data GI are not limited to the information processing apparatus 11 but may be obtained from an image input device, a recording medium such as a memory card, a web site, or the like. As the input unit 101, a serial bus interface such as USB or a network interface such as wired or wireless LAN can be used.

The color matching unit 102 refers to the color matching table 103 having a lookup table (LUT) format, and outputs an R'G'B 'signal by mapping sRGB data to the entire color of the image generating device 13. . The R'G'B 'signal includes a signal of 8 bits each. As the color matching table 103, a plurality of tables corresponding to the type of printing medium and the purpose of image generation are prepared, and the user can select an appropriate table.

The first color separation processing unit 104 refers to the color separation table 105 in the LUT format, and converts the R'G'B 'signal output from the color matching unit 102 into the colorant amount signal CMYK. The color material amount signal CMYK represents the usage amount of cyan C, magenta M, yellow Y, and black K dark printing materials of the image generating device 13, and includes signals of 8 bits each. By the above process, color image data RGB is converted into print data CMYK.

For example, when the colorant amount signal CMYK is (0, 20, 100, 255), each dot of the CMYK colorant is printed with a probability of 0/255, 20/255, 100/255, and 255/255, respectively. In other words, in an image of the pixel number n, 0/255 x n C dots, 20/255 x n M dots, 100/255 x n Y dots, and 255/255 x n K dots are printed. For example, when the color-quantity signal CMYK of all 16x16 pixels (n = 256) is an image of (0, 20, 100, 255), 0 C dots, 20 M dots, 100 Y dots, and 256 K dots are printed.

3 shows an example of the color separation table 105 referred to by the first color separation processing unit 104. In the color separation table 105, for example, each of R'G'B 'is 0, 16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240, One of 17 values of 255 represents a grid point of 17 ³ = 4913. The colorant amount signal value (output value) corresponding to the R'G'B 'value (input value) of each grid point is stored in the color separation table 105.

The second color separation processing unit 106 receives the CMYK signal and the gloss image data GI output from the first color separation processing unit 104, and includes C 'including the signal value of the printing material obtained by lightening the CMYK signal based on the gloss image data GI. Convert to M'Y'K'LcLmGy signal. Although details will be described later, the second color separation processing unit 106 performs conversion in which the total value of the C'M'Y'K'LcLmGy signals becomes larger than the total value of the CMYK signals as the gloss value indicated by the gloss image data GI is lower. .

As mentioned above, in order to increase the unevenness | corrugation of the surface of a printed image, as the gloss reproduced is low, it is necessary to increase the number of lamination | stacking of a printing material. Therefore, as the gloss value is lowered, conversion is performed in which the usage amount of the dark printing material is replaced with the usage amount corresponding to the light printing material. Hereinafter, this conversion by the second color separation processing unit 106 will be referred to as "glossy control conversion".

The reason for performing two types of color separation processing of the first color separation processing unit 104 and the second color separation processing unit 106 is that no glossy control conversion is performed when no decorative printing is performed, that is, when no gloss image data GI is input. This is to use the CMYK signal as it is in the next process. In other words, when the gloss image data GI is not input, the second color separation processing unit 106 passes the CMYK signal.

The path decomposition unit 108 prints the C'M'Y'K'LcLmGy signal output from the second color separation processing unit 106 for each print scan of the image generating device 13 that performs multipath (multipath) printing. A path decomposition process assigned to the path). Details of the multipath printing will be omitted. Although details will be described later, in order to stack the same light printing material based on the gloss value in order to control the unevenness of the surface of the print image, it is necessary to print the same printing material in the same area, To realize.

Although the halftone processing unit 109 will be described later in detail, the halftone processing unit 109 performs a process of determining the dot layout for C _i M _i Y _i K _i Lc _i Lm _i Gy _i after the path decomposition processing, and prints the image generating apparatus 13. Drive data for driving each printing element of the head is generated.

The output data buffer 110 stores the drive data output from the halftone processing unit 109 as image generation data. The image generating data stored in the output data buffer 110 is output to the image generating apparatus 13 through the output unit 111 in synchronization with the image generating operation of the image generating apparatus 13. As the output unit 111, a general-purpose interface such as USB, eSATA, PCI, or PCIe (registered trademark) or a dedicated interface can be used.

[Image generating device and information processing device]

Although details of the configuration of the image generating device 13 are omitted, the image generating device 13 moves the print head vertically and horizontally with respect to the print medium, and prints a binary image of each color material indicated by the image generating data on the print medium. do. In addition, the image generating apparatus 13 adopts a multipass printing method for scanning an image on a print medium several times with a printhead to complete an image, and so-called printing operation for both a forward scan and a home scan of a printhead. Adopt bidirectional printing method. As described above, the image generating apparatus 13 can print-scan the same area of the print medium several times using the same printing material by using a plurality of printing elements.

4 is a block diagram showing an example of the configuration of the information processing apparatus 11. The CPU 171 uses the RAM 173 as a work memory, executes an OS and various programs stored in the ROM 172 and the storage unit 179, and executes (described later) each through the system bus 178. To control wealth.

The storage unit 179 is, for example, an HDD, an SSD, a flash memory, or the like connected to the system bus 178 via the SATA interface (I / F) 176. The general purpose I / F 175 is a serial bus interface such as USB. An input device 14 such as a mouse or a keyboard, an image generating device 13, a general purpose drive 17 for recording media, and the like are connected to the general purpose I / F 175. FIG.

The CPU 171 loads the program designated by the user through the input device 14 from the storage unit 179 into the RAM 173, executes the program, and is connected to the video card (VC) 174. A user interface is displayed at (16). The user selects, creates, and edits color image data and gloss image data input to the image processing apparatus 12 using the user interface. In addition, color image data and gloss image data, or data that is the basis of those image data, are stored in the recording medium of the storage unit 179 or the general-purpose drive 17.

The network interface card (NIC) 177 is a network interface for connecting the information processing apparatus 11 to a network 15 such as a wired LAN or a wireless LAN. Programs executed by the information processing apparatus 11, color image data and gloss image data, or data which is the basis of these image data may be stored in the server apparatus on the network.

The processing and functions of the image processing apparatus 12 can be realized by a printer driver for the image generating apparatus 13 executed by the information processing apparatus 11. Of course, the image processing apparatus 12 can also be provided in the image generating apparatus 13 as hardware. Alternatively, the input unit 101, the color matching unit 102, and the first color separation processing unit 104, which are part of the image processing apparatus 12, are realized by the printer driver, and the second color separation processing unit 106 or later is imaged as hardware. It is also possible to install in the generator 13.

[Image processing]

5 is a flowchart for explaining the generation processing of the image generation data by the image processing apparatus 12. The input unit 101 receives the color image data RGB and the gloss image data GI (step S501). The color matching unit 102 executes color matching processing for converting the input color image data RGB into color signals R'G'B 'depending on the image generating device 13 (step S502).

The first color separation processing unit 104 executes a first color separation processing for converting the color signal R'G'B 'into the printing discretion signal CMYK (step S503). The second color separation processing unit 106 converts the printing quantity signal CMYK into the printing quantity signal C'M'Y'K'LcLmGy including the signal value of the light printing material based on the input gloss image data GI. The process is executed (step S504).

The path decomposition unit 108 executes a path decomposition process for multipass printing the printing discretion signal C'M'Y'K'LcLmGy (step S505). The halftone processing unit 109 executes halftone processing for converting the result of the path decomposition process into drive data for driving each printing element of the image generating device 13 (step S506).

The output unit 111 outputs the image generation data stored in the output data buffer 110 to the image generation device 13 in synchronization with the image generation operation of the image generation device 13 (step S507). The image generation data is output in units such as the entire image or the bandwidth of the print scan. In addition, the process from step S501 to step S506 is repeatedly performed in pixel units.

[Second color separation processing unit]

As described above, the second color separation processing unit 106 includes the printing material amount signal C 'including the signal value of the printing material in which the color material amount signal CMYK output from the first color separation processing unit 104 is light based on the gloss image data GI. Convert to M'Y'K'LcLmGy. At that time, as the gloss value indicated by the gloss image data GI decreases, conversion is performed in which the total value of the C'M'Y'K'LcLmGy signals becomes larger than the total value of the CMYK signals. By increasing the number of laminations of the printing material, the unevenness of the surface of the printed image is increased, and the gloss reproduced by the printed image is reduced.

The gloss value is described using an image clarity value C which shows an image clarity test method of measuring the sharpness of an image reflected on a sample surface. In addition, in the following description, in order to avoid the confusion of the value C of the image clarity and the cyanide value C, the gloss value is described as GI. It is confirmed that it is possible to give a printed effect to the printed matter by changing the image sharpness, and the image sharpness can be controlled by controlling the unevenness of the surface of the printed image. In addition, indices indicating the degree of glossiness of the sample, such as reflective haze and specular image clarity, which are defined in the haze measuring method for measuring the degree of haze on the surface of the sample, are available.

Each of the above indexes is an index representing a different value when the unevenness of the surface of the printed image changes. However, among the above indicators, only the reflection haze is an index whose gloss is lowered as its value is increased. In the following, the gloss value in which the gloss becomes higher as the value thereof is increased will be described. Therefore, in the case of using the reflection haze, a process such as using an inverse is necessary. In addition, these indicators may not have a linear relationship with the glossiness which an image observer feels. Therefore, when the user generates the gloss image data GI, it is preferable to perform appropriate conversion based on the indicator used as the gloss value so that the relationship between the gloss value and glossiness can be intuitively understood.

6 shows an example of the gloss control table 107 referred to by the second color separation processing unit 106. The gloss control table 107 has five values for a combination of any one of nine values of 0, 32, 64, 96, 128, 160, 192, 224, 255, and one of CMYK values, for example, for each CMYK. The gloss value GI is defined and a lattice point of 9 ³ × 5 = 3645 is shown. As gloss value GI, 60, 55, 50, 45, 40 is prescribed, for example. Then, the color material quantity signal value (output value) corresponding to the CMYKGI value (input value) of each grid point is stored in the gloss control table 107.

For example, if the gloss value GI changes at CMYK = (0, 0, 0, 255), the output value changes, and as the GI value decreases, the usage amount of the K printing material is replaced with the usage amount corresponding to the Gy printing material. Gy increases. In addition, in this embodiment, although the laminated number of Gy printing material is demonstrated as two layers, this lamination number is considered in the process result of the 2nd color separation process part 106. As shown in FIG. If the value obtained by dividing the Gy value by 2 and the K 'value are added, the sum is 256 regardless of the gloss value GI. However, the sum totals 255 only when GI = 60 where Gy = 0.

If the input CMYKGI value is the value of the lattice point of the gloss control table 107, the second color separation processing unit 106 outputs the color material quantity signal C'M'Y'K'LcLmGy printed on the lattice point. In addition, if the input CMYKGI value is a value between the lattice points of the gloss control table 107, the second color separation processing unit 106 uses the color material amount signal by interpolation using the value printed on the lattice point surrounding the input value. Outputs C'M'Y'K'LcLmGy.

In the example shown in FIG. 6, the gloss reproduction range of the image generating device 13 is 40 ≦ GI ≦ 60. In other words, the gloss value exceeding the upper limit value (60 in the example shown in FIG. 6) and the gloss value below the lower limit value (GI <40 in the example shown in FIG. 6) are difficult to reproduce. In addition, when a non-reproducible gloss value is input, it is preferable that the application of the information processing apparatus 11 generate a warning.

When the non-reproducible GI value is input, the second color separation processing unit 106 performs the second color separation processing by clipping the GI value to an upper limit value or a lower limit value and setting the GI value within the gloss reproduction range. That is, when the GI value is less than or equal to the upper limit of the gloss reproduction range, the amount corresponding to the GI value can be replaced with the amount corresponding to the light printing material in the amount of the dark printing material indicated by the CMYK signal, and thus C'M'Y ' The total sum of the K'LcLmGy signal values becomes larger than the total sum of the CMYK signal values. The replacement of the usage amount is performed when the GI value is equal to or lower than the upper limit of the gloss reproduction range, and the exchange amount in the replacement of the usage amount increases with the decrease in the GI value.

An example in which the second color separation processing unit 106 uses a multidimensional LUT has been described. However, the second color separation processing unit 106 may perform the second color separation processing using the following formula.

if (Gl> 60) Gl = 60;

if (Gl <40) Gl = 40;

if (C <255) {

      C '= C-Wc × (Glm-Gl);

} else {

      C '= C + 1-Wc × (Glm-Gl);

}

if (C '> 255) C' = 255;

if (C '<0) C' = 0;

if (M <255) {

      M '= M-Wm × (Glm-Gl);

} else {

      M '= M + 1-Wm × (Glm-Gl);

}

if (M '> 255) M' = 255;

if (M '<0) M' = 0;

Y '= Y;

if (K <255) {

      K '= K-Wk × (Glm-Gl);

} else {

      K '= K + 1-Wk × (Glm-Gl);

}

if (K '> 255) K' = 255;

if (K '<0) K' = 0;

Lc = Nlc × Wc × (Glm-Gl);

Lm = Nlm × Wm × (Glm-Gl);

Gy = Ngy × Wk × (Glm-Gl); … (One)

Where Glm is the upper limit of the gloss reproduction range,

Wc, Wm, Wk are weight coefficients depending on the values of C, M, K,

Nlc, Nlm, and Ngy are lamination numbers.

The number of laminations (or usage) of the light printing materials which can colorize the printed matter which changed the lamination number (or usage amount) of the light printing material, and obtain almost the same concentration with respect to the usage amount of the dark printing materials, is K to Gy, and C to Lc. It is used as the lamination number of the light printing material at the time of exchanging from M to Lm. Or the lamination number can be acquired by the following formula from the side color value of the printed matter which printed each printing material one layer (or equivalent amount).

First, the reflectance R '(K) or R' (Gy) of an image printed on one layer (or equivalent) of a K printing material or a Gy printing material and printed on a print medium can be represented by the following equation.

R '(K) = R (K) x Rp;

R '(Gy) = R (Gy) x Rp; … (2)

Where R (K) is the reflectance of the K printing material alone,

R (Gy) is the reflectance of the Gy print group

Rp is the reflectance of the print medium itself.

In formula (2), since R '(K), R' (Gy) and Rp can be measured, reflectances R (K) and R (Gy) can be calculated. In addition, the reflectance R '(Gy_Ngy) when the Gy printing material is laminated Ngy times on a print medium can be represented by the following formula.

R '(Gy_Ngy) = R (Gy) ^Ngy x Rp; … (3)

Therefore, lamination number Ngy for obtaining R '(K) = R' (Gy_Ngy) is represented by a following formula.

Ngy = log {R (K)} / log {R (Gy)}; … (4)

In addition, what is necessary is just to set the natural number closest to Ngy computed by Formula (4) as lamination number. In addition, weight coefficients Wc, Wm, and Wk can be set by measuring the gloss value GI of the printed matter which changed the ratio (area ratio) which turns a dark printing material into a light printing material.

● Ly printing material

The above is based on the premise that the light yellow (Ly) printing material, which is a light printing material corresponding to the Y printing material, is not mounted on the image generating apparatus 13, and therefore, explanation was made assuming Y '= Y. The reason is that the concentration of the Y printing material is low, so that the Ly printing material is not generally used. However, since glossiness cannot be controlled in the areas of C = 0, M = 0, Y> 0, and K = 0, it is preferable to mount the Ly printing material in the image generating device 13. In this case, the exchange from Y value to Ly value follows the following formula.

if (Y <255) {

      Y '= Y-Wy × (Glm-Gl);

} else {

      Y '= Y + 1-Wy × (Glm-Gl);

}

      if (Y '> 255) Y' = 255;

      if (Y '<0) Y' = 0;

Ly = Nly x Wy x (Glm-Gl);

      if (Ly> 255) Ly = 255; … (5)

Where Glm is the upper limit of the gloss reproduction range,

Wy is the weight factor depending on the values of C, M, K,

Nly is the stacking number.

[Path Decomposition]

The path decomposition unit 108 performs a path decomposition process of sharing the C'M'Y'K'LcLmGy signal output from the second color separation processing unit 106 to each recording scan (path).

The multipath printing method will be described briefly. In the inkjet recording system, there is a line system in which a print head having a printing element corresponding to a printing range is used, and an image is printed by moving (sending paper) only the print medium in the sub-scanning direction. In addition, a serial system in which images are printed in sequence by using a printhead having fewer print elements than a line-type printhead, alternately repeating the movement of the printhead in the main scanning direction (print main scan) and paper feeding. There is this. "Print main scanning" means to move (scan) a carriage on which a print head is mounted with respect to a print medium, and "paper supply" is to supply print media by predetermined lengths in a direction orthogonal to the direction of a print main scanning.

By the array density and the number of printing elements of the printhead, the width of the area to be printed is determined by performing one printing main scanning. When an image is printed by one printing scan, the position at which the printing material reaches the printing medium is changed by the influence of manufacturing error of the printing element and the airflow generated around the printhead by the printing main scanning. As a result, a shaded line called "banding" is formed, which degrades image quality.

In order to alleviate the above problems and to improve image quality, a multipath recording method is adopted. In this embodiment, in order to control the unevenness | corrugation of the surface of a printed image, light printing material is laminated | stacked. Therefore, it is necessary to print the same printing material in the same area, and the multipass printing which implements this is performed by several print scans.

In the multipath recording method, an image is completed by several print main scans. Therefore, printable image generation data is not completely recorded by one printing main scanning. A path decomposition process will be described with reference to FIGS. 7A, 7B, and 7C. 7A shows an example of a printing rate table showing a printing rate for each print scan. The value of the C'M'Y'K'LcLmGy signal can be assigned to each print scan (pass) according to the print rate table. In other words, the value obtained by multiplying the signal value by the print rate is the amount of printing material used in each path.

In the case where the unit region of the rear halftone processing has 4 x 4 dots, for example, the number of gradations that can be reproduced by 4 x 4 dots is 16. In this case, the path decomposition unit 108 converts the C'M'Y'K'LcLmGy signal of each 8-bit color into a 4-bit signal of 0-15. Fig. 7B shows the result of converting the upper 4 bits of the K'Gy value (each 8 bits) after the second color separation process into a signal of each 4 bits.

FIG. 7C shows the path decomposition data assigned to each path based on the printing rate by converting the K " Gy " value converted into 4 bits, that is, the output from the path decomposition unit 108. As shown in FIG. The path decomposition unit 108 converts the C'M'Y'K'LcLmGy signal into C _i M _i Y _i K _i Lc _i Lm _i Gy _i which is path decomposition data of the i-th path.

The path decomposition unit 108 sequentially determines path decomposition data according to the print rate table from the first path, and performs processing similar to the error diffusion processing of propagating the redundant path to the next path. That is, the error (extra) in the target path is propagated to the next path, and the path decomposition data of the path is determined by the signal value obtained by adding the error and the printing rate of the next path. When the 4-bit signal value is 0xF = 15, the path decomposition unit 108 performs a path decomposition process with the signal value "16". 7B and 7C also show reference GI values, needless to say, that the GI values are not directly related to the processing of the path decomposition section 108.

[Halftone processing part]

The halftone processing unit 109 determines the dot layout corresponding to the path decomposition data C _i M _i Y _i K _i Lc _i Lm _i Gy _i . That is, the halftone processing unit 109 generates, for each printing material, a 1-bit print signal indicating the print position of the dot from the path decomposition data. This print signal is output as a drive signal (1 bit) of each printing element of the image generating device 13 through the output unit 111.

● dark printing material

8A, 8B, and 8C show an example of a 4 × 4 dither matrix for halftone processing that quantizes path decomposition data of a K ″ signal into a 1-bit drive signal. That is, the halftone processing unit 109 is illustrated in FIG. 8A. The dot layout of each pass of K printing material is determined using the dither matrices shown in Figs.

In the first pass, the halftone processing unit 109 is '1' as a print signal from the cell having the minimum value in the initial dither matrix (FIG. 8A) to the cell having the same value as the path decomposition data in sequence. '(Dot on)' is set, and '0' (dot off) is set as the print signal of another cell.

Then, the halftone processing unit 109 subtracts the path decomposition data of the first pass from the value of each cell of the dither matrix. If a cell having a value smaller than 0 appears, the halftone processing unit 109 adds 16 to the cell in order to maintain the cell value within the range of 1-16. 8B and 8C show updating of the dither matrix when the path decomposition data is "4", respectively.

In the second pass, the halftone processing unit 109 performs the same process as the first pass using the update dither matrix (Fig. 8C). By repeating this process for all the passes, the dot layout of each pass of the dark printing material is determined.

Fig. 9 shows the halftone processing results of the path decomposition data of the K ″ value shown in Fig. 7C. In Fig. 9, a cell printed with “K” corresponds to on-dot. Fig. 9 is a reference GI value. It goes without saying that the GI value does not directly relate to the processing of the halftone processing section 109.

● light printing materials

The halftone processing of the path decomposition data of the Gy "value will be described with reference to Figs. 10A and 10B. Fig. 10A is a 4 x 4 dither for halftone processing for quantizing the path decomposition data of the Gy" signal into a 1-bit drive signal. An example of a matrix is shown. That is, the halftone processing unit 109 determines the dot layout of each path of the Gy printing material by using the dither matrix shown in FIG. 10A.

In the first pass, the halftone processing unit 109, like the halftone processing of the dark printing material, has a '1' (as a print signal from a cell having a minimum value to a cell having a value equal to the path decomposition data in sequence. Dot on) and '0' as the print signal of another cell.

In the case of halftone processing of a dark printing material, the dither matrix is updated after the halftone processing of each pass. On the other hand, in the case of halftone processing of light printing materials, if the total number of passes is P and the number of stacked layers is N, after performing halftone processing corresponding to the number of passes int (P / N), the halftone processing unit 109 The dither matrix is initialized to enable lamination of light printing materials. By this initialization, the overlap of on-dots of the light printing material occurs in the printing scan of the image generating device 13.

For example, in the case of P = 4 and N = 2, after halftone processing of the second pass, the dither matrix is initialized, and overlapping of on-dots of light printing material occurs. In addition, in the case of P = 4 and N = 3, after halftone processing of the 1st, 2nd, and 3rd pass, a dither matrix is initialized and superimposition of on-dot of light printing material arises. By the initialization of the dither matrix, it is possible to again turn on a cell which has already been "on the dot", and it is possible to stack light printing materials at the same cell position.

Fig. 10B shows the halftone processing result of the path decomposition data of the Gy "value shown in Fig. 7C. In Fig. 10B, the cell printed with" G "corresponds to on-dot and the cell printed with" 2G "is Gy. The printing material corresponds to a dot having two layers, although Fig. 10B shows a reference GI value, needless to say that the GI value does not directly relate to the processing of the halftone processing section 109.

Comparing the final dot layout shown in Figs. 9 and 10B, it is understood that K dots and Gy dots are arranged exclusively. That is, according to gloss value GI, each K dot is exchanged with Gy dot of 2 layers. When the gloss value GI has the lowest value (GI = 40 in this example), the area ratio of K dots and the area ratio of Gy dots are the same, so that the K dots of the first layer and the Gy dots of the second layer are arranged in a checkerboard shape. As a result, the thickness of the printing material is different between the adjacent dots, and the unevenness (high level difference) of the surface of the printed image is maximum.

In the above, an example of four print scans (four passes) has been described. However, since two-layer light printing materials and one-layer dark printing materials need to be printed, an image can be generated even in two passes. In addition, even when four passes are used, light printing materials can be recorded in the same area in successive passes. However, irrespective of this, there are the following reasons of performing four-pass printing and not printing the printing material in the same area in a continuous path.

The printing material lands on the printing medium in a liquid state, and is gradually fixed on the printing medium as a solid by penetration of the solvent into the printing medium or evaporation in the air. In other words, the printing material immediately after the impact on the printing medium is in a wet state. Therefore, by giving a time difference to an impact, it waits for the fixation of the printing material which arrived at first, and reaches a printing material in the same area after that. This aims to prevent diffusion of the wet printing material and to laminate more bulky printing material.

As mentioned above, based on the input gloss image data GI, the usage amount of the dark printing material acquired by the color separation process of color image data is exchanged with the usage amount of the light printing material. Further, the dot layout of the soft printing material is determined so that the dots of the printing material overlap, and the unevenness of the surface of the printed image is controlled. Therefore, the lower the gloss value reproduced, the larger the area ratio which increases the unevenness of the surface of the printed image. As a result, desired glossiness reproduction in a printed image can be obtained.

Second Embodiment

The image processing apparatus and image processing method of the second embodiment according to the present invention will be described below. In addition, in 2nd Example, about the structure substantially the same as 1st Example, the same code | symbol may be attached | subjected and the detailed description may be abbreviate | omitted.

[summary]

In the first embodiment, the lower the gloss value reproduced based on the gloss image data GI is, the more the printing amount of the dark printing material is replaced with the usage amount corresponding to the lighter printing material, and the dot layout of the light printing material is determined so that the dots of the light printing material overlap. The method of controlling the unevenness of the surface of the printed image was explained.

The image generating apparatus 13 is a red (R) printing material, a blue (B) printing material, a green (G) printing material, or the like, in addition to the CMYK printing material (hereinafter, referred to as a basic color printing material). There may be a case where a printing material (hereinafter referred to as a characteristic printing material) called a characteristic is mounted. In the second embodiment, an example in which the present invention is applied to an image generating device 13 on which seven-color printing materials of CMYKRGB are mounted will be described.

The image generating apparatus 13 equipped with the basic color printing material and the characteristic printing material, the lower the gloss value to reproduce, exchanges the usage amount of the characteristic printing material with the usage amount corresponding to the CMY printing material and the dot of the CMY printing material so that the CMY printing material overlaps. By determining the layout, the unevenness of the surface of the printed image is controlled.

1C shows a state in which an image is formed in all areas of a predetermined area. FIG. 1D shows a state in which an image is formed by the R printing material of one layer and the superposition of the Y printing material and the M printing material. The reproduced color is the same as in the case of Fig. 1C. In the case shown in Fig. 1D, an area formed only of the R printing material and an area formed by lamination of the Y printing material and the M printing material are mixed, and the unevenness of the surface of the printed image increases and the gloss decreases.

[Configuration of the device]

11 is a block diagram showing an example of the configuration of the image processing apparatus 12 of the second embodiment. The first color separation processing unit 114 refers to the color separation table 115 and converts the R'G'B 'signal output from the color matching unit 102 into the colorant amount signal CMYKRGB. The color material amount signal CMYKRGB represents the usage amount of the basic color printing material of the image generating device 13 and the usage amount of the characteristic printing material. Each of the CMYKRGB signals is an 8-bit signal. By the above process, color image data RGB is converted into print data CMYKRGB.

The second color separation processing unit 116 receives the CMYKRGB signal and the gloss image data GI output from the first color separation processing unit 114, and converts the CMYKRGB signal to C'M'Y'KR'G 'based on the gloss image data GI. Convert to B 'signal. The second color separation processing unit 116 converts the sum value of the C'M'Y'KR'G'B 'signals to be larger than the sum value of the CMYKRGB signal. In other words, in order to increase the unevenness of the surface of the printed image as the gloss reproduced is lower, the second color separation processing unit 116 performs gloss control conversion by exchanging the usage amount of the RGB printing material with the usage amount corresponding to the CMY printing material.

The second color separation processing unit 116 refers to the gloss control table 117 to perform gloss control conversion. If the input CMYKRGBGI value is the value of the grid point of the gloss control table 117, the second color separation processing unit 116 outputs the color quantity signal C'M'Y'KR'G'B 'printed on the grid point. . Further, if the input CMYKRGBGI value is a value between the lattice points of the gloss control table 117, the second color separation processing unit 116 uses the color material amount signal C by interpolation processing using the value printed on the lattice point surrounding the value. Outputs 'M'Y'KR'G'B'

12A and 12B, gloss control conversion and path decomposition processing will be described. FIG. 12A shows a case in which red print data having a CMYKRGB value (0, 0, 0, 0, 255, 0, 0), that is, reproducible only by R printing material, is input to the second color separation processing unit 116. In this case, as shown in the second to fourth columns in the table shown in Fig. 12A, in the case of gloss value GI = 60, Y printing material and M printing material are not used, but as gloss value GI decreases, R Reduce the amount of printing material used. Then, the amount of use of the Y printing material and the M printing material which can reproduce red color by subtractive mixing is increased. Of course, in the case of red color which cannot be reproduced only by the R printing material, the result of the first color separation process is Y ≧ 0, M ≧ 0, K ≧ 0, and R <255. However, even in this case, as the gloss value GI decreases, the usage amount of the R printing material is decreased, and the usage amount of the Y printing material and the M printing material is increased.

Although not shown in FIG. 12A, when the result of the first color separation treatment indicates G = 255, the Y printing material and C capable of reproducing green color by subtractive mixing are reduced as the gloss value GI decreases. Increase the amount of printing material used. Similarly, when the result of the first color separation treatment indicates B = 255, and the like, as the gloss value GI decreases, the amount of use of the B printing material decreases, and the amount of use of the C printing material and the M printing material which can reproduce blue color by subtractive color mixing is reduced. Increase.

The path decomposition unit 118 performs a path decomposition process of assigning signal values of C'M'Y'KR'G'B output from the second color separation processing unit 116 to each print scan (path). Similarly to the first embodiment, the path decomposition section 118 uses the print rate table shown in Fig. 7A, and the unit area in the halftone processing section 119 has 4 x 4 dots. Therefore, the path decomposition unit 118 converts each 8-bit C'M'Y'KR'G'B 'signal into a 4-bit signal. The fifth to seventh columns in the table shown in FIG. 12A show the results of conversion from the upper 4 bits of the R'Y'M 'value (8 bits of each color) to the signal of 4 bits of each color after the second color separation processing.

Fig. 12B shows the path decomposition data assigned to each path based on the printing rate after the R " Y " M " value has been converted to 4 bits, and shows the output of the path decomposition section 118. The path decomposition section 118 , Converts the C'M'Y'KR'G'B 'signal to C _i M _i Y _i K _i R _i G _i B _i , which is path decomposition data of the i-th pass.

The halftone processing unit 119 determines the dot layout for C _i M _i Y _i K _i R _i G _i B _i after the path decomposition processing. That is, the halftone processing unit 119 generates one-bit print signal indicating the print position of the dot on the print material from the path decomposition data. In this process, Fig. 8A is used as the initial dither matrix for the feature printing material. 10A is also used as the initial dither matrix for the primary color printing material. However, unlike the first embodiment in which the same printing material is laminated, since different printing materials are laminated, the dither matrix is not initialized during halftone processing.

Fig. 13 shows the halftone processing results of the path decomposition data of the R ″ value shown in Fig. 12B. In Fig. 13, a cell printed with “R” corresponds to on-dot. Y printing material exchanged from the R printing material. The same cell is assigned to on dot for the and the M printing materials Fig. 14 shows the halftone processing result of the path decomposition data of Y " M " value shown in Fig. 12. In Fig. 14, " YM " The cells shown correspond to the on-dots of the Y printing material and the M printing material .. Figures 13 and 14 also show reference GI values, but it should be noted that the GI values are not directly related to the processing of the halftone processing unit 119. There is no.

Comparing the final dot layout shown in Figs. 13 and 14, it is understood that R dots and YM dots are arranged exclusively. That is, according to the gloss value GI, each R dot is exchanged for two layers of YM dots. If the gloss value GI has the lowest value (GI = 40 in this example), the area ratio of the R dots and the area ratio of the YM dots are the same, so that the R dots of the first layer and the YM dots of the second layer are arranged in a checkerboard shape. . As a result, the thickness of a printing material differs between adjacent dots, and the unevenness | corrugation (the height difference) of the surface of a printed image becomes the maximum.

In the above, in order to simplify description, the example which applies FIG. 7A as the printing rate table of all the printing materials was demonstrated. Therefore, the Y printing material and the M printing material are printed in the same area with the same number of passes. As described in the first embodiment, in order to obtain a difference in hit time between overlapping printing materials, a different printing rate table is used for each of the C printing material, Y printing material, and M printing material.

As described above, based on the input gloss image data GI, the usage amount of the characteristic printing material obtained by the color separation processing of the color image data is replaced with the usage amount of the CMY printing material. Further, the dot layout of the CMY printing material is determined so that the CMY printing material overlaps, and the unevenness of the surface of the printed image is controlled. Therefore, the lower the gloss value reproduced, the larger the area ratio which increases the unevenness of the surface of the printed image. This makes it possible to obtain desired gloss reproduction in the printed image.

If the process of step S503 in Fig. 5 is replaced by R'G'B '→ CMYKRGB, and the process of step S504 in Fig. 5 is replaced by CMYKRGB → C'M'Y'KR'G'B', then FIG. It becomes like the flowchart which shows the generation process of the image generation data of 2nd Example. Therefore, the flowchart showing the generation process of the image generation data of the second embodiment is omitted.

Third Embodiment

The image processing apparatus and image processing method of the third embodiment according to the present invention will be described below. In addition, in 3rd Example, about the structure substantially the same as 1st and 2nd Example, the same code | symbol is attached | subjected and the detailed description may be abbreviate | omitted.

[summary]

In the first and second embodiments, the replacement of the usage amount of the dark printing material into the usage amount of the light printing material, the usage amount of the characteristic printing material from the usage amount of the CMY printing material, the lamination of the soft printing material or the CMY printing material was described. The image generating apparatus 13 may be equipped with a substantially colorless transparent clear material in addition to the dark printing material (primary color printing material), the light printing material, and the characteristic printing material. In the third embodiment, an example in which the present invention is applied to the image generating apparatus 13 on which the CMYK four-color basic color printing material and the CL material are mounted will be described.

A clear material (hereinafter CL material) is mainly used as a gloss adjusting material for adjusting the gloss of printed matter, and is generally used for a purpose of increasing gloss. On the other hand, in the third embodiment, the lower the gloss reproduced, the more the amount of the CL material is used to increase the unevenness of the surface of the printed image. In addition, even if there are some colors and some blurs in CL material, it does not mind.

[Configuration of the device]

15 is a block diagram showing an example of the configuration of the image processing apparatus 12 of the third embodiment. The clear material adding unit (CL material adding unit) 126 receives the CMYK signal and the gloss image data GI output from the first color separation processing unit 104, determines the CL value based on the gloss image data GI, and CMYKCL Output the signal. The CL material adding unit 126 increases the CL value as the gloss value indicated by the gloss image data GI decreases. That is, as the gloss reproduced decreases, in order to increase the unevenness of the surface of the printed image, the amount of use of the CL material is increased.

The CL material adding unit 126 refers to the one-dimensional gloss control table 127 to determine the CL signal value. If the gloss value GI inputted is a recording value of the gloss control table 127, the CL material adding unit 126 outputs a CMYKCL signal to which the CL value corresponding to the gloss value GI is added. In addition, if the gloss value GI inputted is a value between the print values of the gloss control table 127, the CL material addition unit 126 will determine the CL value determined by interpolation processing using the print value with the gloss value sandwiched therebetween. Outputs a CMYKCL signal added with.

16A and 16B, the determination of the CL value and the path decomposition process will be described. FIG. 16A shows a case where CMYK values (0, 0, 0, 255), that is, black print data reproducible only with the K printing material, are input to the CL material adding unit 126. FIG. As shown in the second column in the table of Fig. 16A, the amount of the K printing material used is irrelevant to the gloss value GI. On the other hand, as shown in the third column, in the case of gloss value GI = 60, the CL material is not used, and as the gloss value GI decreases, the amount of the CL material used increases. In other words, while maintaining the CMYK signal value, as the gloss value GI decreases, the usage amount of CL printing material increases.

The path decomposition unit 128 performs a path decomposition process of allocating the CMYKCL signal value output from the CL material adding unit 126 to each print scan (path). Similarly to the first embodiment, the path decomposition section 128 uses the print rate table shown in Fig. 7A, and the unit area in the halftone processing section 129 has 4 x 4 dots. Therefore, the path decomposition unit 128 converts each 8-bit CMYKCL signal into a 4-bit signal. The fourth and sixth columns in the table shown in Fig. 16A show the results of conversion from the upper four bits of the KLC signal (each 8 bits) to the signals of each four bits.

Fig. 16B shows the path decomposition data assigned to each path based on the printing rate by the K " LC " value after conversion to 4 bits, and shows the output from the path decomposition unit 128. Figs. The path decomposition unit 128 converts the CMYKLC signal into C _i M _i Y _i K _i LC _i , which is path decomposition data of the i-th path.

The halftone processing unit 129 determines the dot layout for C _i M _i Y _i K _i CL _i after the path decomposition processing. In other words, the halftone processing unit 129 generates a 1-bit print signal indicating the print position on the dot from the path decomposition data for each printing material. In this process, Fig. 8A is used as the initial dither matrix for the basic color printing material. In addition, FIG. 10A is used as a dither matrix for CL materials. However, unlike the first embodiment in which the same printing material is laminated, since the primary color printing material and the CL material are laminated, the dither matrix is not initialized during halftone processing.

Halftone processing will be described with reference to Figs. 17A and 17B. Fig. 17A shows the result of halftone processing of the path decomposition data of the K ″ value shown in Fig. 16B. In Fig. 17A, a cell printed with “K” corresponds to on-dot. Fig. 17B is shown in Fig. 16B. Halftone processing results of the path decomposition data of the indicated CL " In Fig. 17B, the cell printed with " CL " corresponds to the on-dot of the CL material. 17B also shows a reference GI value, needless to say, that the GI value is not directly related to the processing of the halftone processing section 119.

17A and 17B show that the K printing material is printed in the entire area, the CL material is superimposed on the K printing material when GI = 60, and the overlap area of the CL material increases as the gloss value GI decreases. In addition, since unevenness | corrugation should just be formed in the surface of a printed image, you may arrange | position CL material on a base color printing material, and may arrange | position a base color printing material on CL material.

18 is a flowchart for explaining processing for generating image generation data by the image processing apparatus 12 of the third embodiment. The input unit 101 inputs color image data RGB and glossy image data GI (step S601). The color matching unit 102 performs color matching processing for converting the input color image data RGB into color signals R'G'B 'depending on the image generating device 13 (step S602).

The first color separation processing unit 104 executes the first color separation processing for converting the color signal R'G'B 'into the printing discretion signal CMYK (step S603). The CL material adding unit 126 outputs the printing discretion signal CMYKCL to which the CL discretion based on the input gloss image data GI is added (step S604).

The path decomposition unit 128 performs a path decomposition process for multipass printing the print discretion signal CMYKCL (step S605). The halftone processing unit 129 executes halftone processing for converting the result of the path decomposition process into driving data for driving each printing element of the image generating device 13 (step S606).

The output unit 111 outputs the image generation data stored in the output data buffer 110 to the image generation device 13 in synchronization with the image generation operation of the image generation device 13 (step S607). The image generation data is output in units such as the entire image or the bandwidth of the print scan. In addition, the process from step S601 to step S606 is repeatedly performed in pixel units.

As described above, the usage amount of the CL material is determined based on the input gloss image data GI, and as the gloss value decreases, the usage amount of the CL material is increased. In addition, the dot layout is determined so that the primary color printing material and the CL material overlap, and the unevenness of the surface of the printed image is controlled. Therefore, as the gloss value reproduced decreases, the area ratio for increasing the unevenness of the surface of the printed image increases, so that desired gloss reproduction can be obtained in the printed image.

[Example 4]

The image processing apparatus and image processing method of the fourth embodiment according to the present invention will be described below. In addition, in 4th Example, about the structure substantially the same as 1st-3rd Example, the same code | symbol may be attached | subjected and the detailed description may be abbreviate | omitted.

[summary]

In the first embodiment, as the gloss value reproduced based on the gloss image data GI decreases, the usage amount of the dark printing material is replaced with the usage amount corresponding to the LcLmGy printing material, and the dot layout of the light printing material is determined so that the light printing material overlaps, thereby printing. The method of controlling the unevenness of the surface of the image has been described.

The image generating apparatus 13 may mount a plurality of relatively low density black type printing materials with relatively low density with respect to the K printing material which is a relatively high density black type printing material and is contained in a basic color printing material. For example, the image generating apparatus 13 may mount three types of printing materials, namely, K, Gy, and Lgy, in order of high density as a black printing material (hereinafter referred to as BK printing material). In this case, Gy and Lgy are low concentration black printing materials. In the fourth embodiment, an example in which the present invention is applied to the image generating apparatus 13 on which the six-color printing material of CMYKGyLgy is mounted will be described.

When using three kinds of BK printing materials, K printing material is replaced by lamination of Gy printing material or lamination of Lgy printing material, and lamination of K printing material, Gy printing material, and Lgy printing material of one layer is performed. By mixing them, lower gloss can be realized.

FIG. 1E shows an image in which part of the K printing material is replaced with a two-layer Gy printing material. 1F shows an image in which a part of the K printing material is replaced with a Lgy printing material of four layers. In addition, the premise is that the color reproduced by the two-layer Gy print material, the color reproduced by the four-layer Lgy print material, and the color reproduced by the K print material on the first floor are the same. 1G shows an image in which part of the K printing material is replaced with a two-layer Gy printing material or a four-layer Lgy printing material.

The graph shown on the right side of each of FIGS. 1E, 1F, and 1G shows a histogram (normal histogram) of the normal angle of the surface of the corresponding printed image. These histograms are obtained by dividing the measurement results of the surface shapes of the samples of FIGS. 1E, 1F, and 1G into fine regions and measuring the normal direction of each fine region.

Comparing the normal histogram shown in FIG. 1E with the normal histogram shown in FIG. 1F, it is understood that the most frequent normal angles are different. Moreover, in the normal histogram shown in FIG. 1G, frequency distribution is wide. That is, the surface of the minute region in the image shown in the image of FIG. 1G is inclined in various directions, and as a result, the direction of light reflected from the image surface is also distributed at various angles. Therefore, the gloss of the image shown in Fig. 1G is lower than the image shown in Figs. 1E and 1F.

[Configuration of the device]

19 is a block diagram showing an example of the configuration of the image processing apparatus 12 of the fourth embodiment. The black decomposition processing unit (BK decomposition processing unit) 136 receives the CMYK signal and the gloss image data GI output from the first color separation processing unit 104, and decomposes the BK printing material based on the gloss image data GI. Processing is performed to convert the CMYK signal into a CMYK'GyLgy signal. The BK-based decomposition processing unit 136 converts the amount of K printing material to the amount corresponding to the Gy printing material or the amount corresponding to the Lgy printing material as the gloss value indicated by the gloss image data GI decreases. That is, in order to increase the unevenness of the surface of the printed image as the gloss reproduced decreases, gloss control conversion is performed to increase the amount of Gy printing material and Lgy printing material used.

The BK-based decomposition processing unit 136 refers to the gloss control table 137 to perform gloss control conversion. If the input CMYKGI value is the value of the grid point of the gloss control table 137, the color material amount signal CMYK'GyLgy printed on the grid point is output. In addition, if the input CMYKGI value is a value between the lattice points of the gloss control table 137, the BK-based decomposition processing unit 136, by using interpolation processing using the value printed on the lattice point surrounding the value, the color material amount signal Print CMYK'GyLgy.

The gloss control conversion and path decomposition processing will be described with reference to Figs. 20A and 20B. 20A shows a case where CMYK values (0, 0, 0, 0, 255), that is, black print data reproducible only with the K printing material, are input to the BK-based decomposition processing unit 136. In this case, as shown in the 2nd-4th column in the table of FIG. 20A, in the case of gloss value GI = 60, Gy printing material and Lgy printing material are unused. However, when the GI value decreases, the usage amount of the K printing material is reduced, and the use of the Gy printing material is first started.

In addition, if the GI value is further reduced, the usage amount of the Gy printing material is increased, and the use of the Lgy printing material is started. If the GI value further decreases thereafter, the increase in the amount of Gy printing material stops, and the amount of Lgy printing material is increased. That is, the usage amount is exchanged with the low density black printing material of the number corresponding to GI value.

The path decomposition unit 138 performs a path decomposition process of assigning signal values of CMYK'GyLgy output from the BK system decomposition processing unit 136 to each print scan (path). As in the first embodiment, the path decomposition section 138 uses the print rate table shown in Fig. 7A, and the unit area in the halftone processing section 139 has 4 x 4 dots. Therefore, the path decomposition unit 138 converts each 8-bit CMYK'GyLgy signal into a 4-bit signal. The fifth to seventh columns in the table of FIG. 20A show the results of conversion from the upper 4 bits of the K'GyLgy value (each 8 bits) to the signal of each 4 bits.

20B shows the path decomposition data assigned to each path based on the printing rate by the K "LC" value after conversion to 4 bits, and shows the output of the path decomposition unit 138. The path decomposition unit 138 converts the CMYK'GyLgy signal into C _i M _i Y _i K _i Gy _i Lgy _i which is path decomposition data of the i-th path.

The halftone processing unit 139 determines the dot layout for C _i M _i Y _i K _i Gy _i Lgy _i after the path decomposition process. In other words, the halftone processing unit 139 generates a 1-bit print signal indicating the print position on the dot from the path decomposition data for each printing material. In this process, Fig. 8A is used as the initial dither matrix for the basic color printing material. Therefore, the result of halftone processing the path decomposition data of the K "value shown in FIG. 20B is as shown in FIG.

Referring to Figs. 21A and 21B, halftone processing of a Gy printing material will be described. 21A shows an example of the initial dither matrix for the Gy printing material. In order to overlap the Gy printing material in two layers, as in the first embodiment, the dither matrix is initialized during halftone processing. Fig. 21B shows the result of halftone processing of the path decomposition data of the Gy "value shown in Fig. 20B. In Fig. 21B, the cell printed with" G "corresponds to on-dot and the cell printed with" 2G ". It corresponds to the dot which has this Gy printing material of two layers, respectively.

Referring to Figs. 22A and 22B, halftone processing of the Lgy printing material will be described. 22A shows an example of a dither matrix for Lgy printing material. In order to superimpose the Lgy printing material in four layers (to superimpose in all passes), the dither matrix is not initialized during halftone processing. Fig. 22B shows the result of halftone processing of the path decomposition data of the Lgy "value shown in Fig. 20B. In Fig. 22B, the cell printed with" Lg "corresponds to on-dot and the cell printed with" 4L ". Corresponding to the dot having each of the four layers of Lgy printing material, Figs. 21B and 22B also show reference GI values, but it is to be noted that the GI values are not directly related to the processing of the halftone processing unit 139. There is no need.

Fig. 23 shows the final dot layout of the BK printing material. As the gloss value GI decreases, the print image generation dot is "K dot of 1st layer" → "K dot of 1st layer + Gy dot of 2nd layer" → "K dot of 1st layer + Gy dot of 2nd layer + 4th layer Lgy is changed to a dot ". As described above, if the relationship between the density Dk of the K printing material, the concentration Dgy of the Gy printing material, and the density Dlgy of the Lgy printing material is Dk: Dgy: Dlgy = 4: 2: 1, the color is within the 4 × 4 region shown in FIG. 23. No change of was observed, so that the gloss corresponding to the gloss value GI was reproduced in the image.

As described above, a plurality of BK-based printing materials having different concentrations are used, and the amount of K-printing material used is distributed to the amounts of use of the plurality of low-concentration BK-based printing materials. Further, the dot layout of the plurality of low-concentration BK-based printing materials is determined so as to obtain the overlap of the number of layers corresponding to the concentrations of the plurality of low-concentration BK-based printing materials, and the unevenness of the surface of the printed image is controlled. Therefore, it becomes possible to control the area ratio which increases the unevenness of the surface of the printed image in multiple stages. Thereby, desired glossiness reproduction and smoother glossiness change in a printed image can be obtained.

In addition, the gloss can be reduced regardless of the gradation. In particular, in the dark part of an image, a decorative effect can be improved by extending the reproduction range on the low gloss side. Further, when the high density printing material having a relatively high concentration is replaced with a low concentration printing material having a relatively low density in area units to increase the unevenness of the surface of the printed image, the color or density of the adjacent area becomes as equal as possible. By doing in this way, there exists an effect which prevents the fall of granularity.

If the process of step S504 in Fig. 5 is replaced with CMYK? CMYK'GyLgy, Fig. 5 is the same as a flowchart showing the process of generating image generation data of the fourth embodiment. Therefore, the flowchart showing the generation process of the image generation data of the fourth embodiment is omitted.

Other embodiments

Further embodiment (s) of the present invention may be executed on a computer recorded on a storage medium (eg, a non-transitory computer readable storage medium) to perform one or more of the above-described embodiment (s). One or more circuits (eg, Application Specific Integrated Circuits) that read and execute possible instructions (e.g., one or more programs) and perform one or more of the above-described embodiment (s). Can be realized by a computer of a system or apparatus, including, for example, by reading and executing computer executable instructions from a storage medium to perform one or more of the above-described embodiment (s). And / or by a method performed by a computer of a system or apparatus by controlling one or more circuits to perform one or more functions of the above-described embodiment (s). Can be realized. The computer may include one or more of a central processing unit (CPU), a micro processing unit (MPU), or other circuitry, and may include a separate computer or a network of independent computer processors. These computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may be, for example, a hard disk, random-access memory (RAM), read only memory (ROM), storage in a distributed computing system, an optical disk (compact disk (CD), digital versatile disc (DVD), or blue-ray). Disc (BD) ^TM, etc.), a flash memory device, or a memory card.

While the invention has been described with reference to exemplary embodiments, it will be understood that the invention is not limited to this disclosed exemplary embodiment. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications and equivalent structures and functions.

Claims (11)

An input unit configured to receive a first printing quantity signal and glossy image data indicating a usage amount of the dark printing material of the image to be generated;
Generating a second printing quantity signal in which the usage amount corresponding to the gloss image data is replaced with the usage amount corresponding to the light printing material having a lower concentration than the dark printing material among the usage amounts of the dark printing material indicated by the first printing material quantity signal. And a color separation unit configured to
The gloss of the image is controlled by the unevenness generated corresponding to the configuration of the dot of the soft printing material.
The method of claim 1,
The dark printing material is a high density black printing material, and the light printing material is a low concentration black printing material.
The method of claim 2,
And a path decomposition unit configured to convert the second printing discretion signal into path decomposition data corresponding to each print scan of the image generating apparatus,
The image growth growth value is the low concentration black printing material, and includes a plurality of low concentration black printing materials having different concentrations,
And the color separation unit exchanges the amount of use of the low concentration black printing material corresponding to the gloss image data.
The method of claim 3, wherein
And when the gloss image data is equal to or less than an upper limit of the gloss reproduction range of the image generating device, an amount of usage is changed.
The method of claim 1,
And the amount of exchange in the exchange of the amount of usage increases with the decrease in the gloss image data.
The method of claim 1,
And the total sum of the signal values of the second print discretion signal becomes larger than the total sum of the signal values of the first print discretion signal by exchange of the usage amount.
An input unit configured to receive a first print quantity signal and glossy image data indicating a usage amount of the basic color printing material and an amount of the characteristic printing material reproducing a color different from the basic color printing material of the image to be generated;
A second printing quantity signal for exchanging the usage amount corresponding to the gloss image data among the usage amounts of the feature printing material indicated by the first printing amount signal by the usage amount corresponding to the plurality of basic color printing materials corresponding to the feature printing material. And a color separation unit configured to produce
The glossiness of the image is controlled by the unevenness generated corresponding to the configuration of the dots of the plurality of primary color printing materials.
The method of claim 7, wherein
And the plurality of basic color printing materials corresponding to the characteristic printing material are combinations of basic color printing materials capable of reproducing a color reproduced by the characteristic printing material.
Receiving a first print quantity signal and glossy image data indicating a usage amount of the dark printing material of the image to be generated;
Generating a second printing quantity signal in which the usage amount corresponding to the gloss image data is replaced with the usage amount corresponding to the light printing material having a lower concentration than the dark printing material among the usage amounts of the dark printing material indicated by the first printing amount signal; Including the steps of:
The glossiness of the image is controlled by the unevenness generated corresponding to the configuration of the dot of the soft printing material.
The method of claim 9,
The dark printing material is a high density black printing material, and the light printing material is a low concentration black printing material.
Receiving a first print quantity signal and glossy image data indicating a usage amount of the basic color printing material and the usage amount of the feature printing material reproducing a color different from the basic color printing material of the image to be generated;
A second printing quantity signal for exchanging the usage amount corresponding to the gloss image data among the usage amounts of the feature printing material indicated by the first printing amount signal by the usage amount corresponding to the plurality of basic color printing materials corresponding to the feature printing material. Generating a;
The glossiness of the image is controlled by the unevenness generated corresponding to the configuration of the dots of the plurality of primary color printing materials.

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