JP6516717B2 - Image processing apparatus and image processing method - Google Patents

Description

  The present invention relates to an image processing technique for controlling the gloss characteristics of an image formed on a recording medium.

  In recent years, in the field of commercial printing and the like, the demand for high-quality and unique printed materials is increasing. As means for realizing this, there is a technique of controlling the gloss characteristics of the printed matter for each area of the image to be recorded. It is known that the gloss characteristics of the printed matter are related to the irregularities on the surface of the printed matter. By reducing the irregularities on the surface of the printed matter, control such as high gloss expression can be performed, and on the contrary, low gloss expression can be controlled. Patent Document 1 describes that recording is performed more frequently by stacking ink at a plurality of target positions spaced by ink dot spacing, rather than recording in which ink target positions are different depending on the ink dots. ing. It is stated that, by this, the smoothness of the surface is reduced to realize low gloss expression.

JP, 2014-40011, A

  However, in the technique of stacking and recording ink dots for the purpose of reducing gloss as in Patent Document 1, the coverage of the ink on the recording medium is reduced. The range of density that can be expressed on the recording medium is narrowed. On the other hand, when ink dots are recorded at a position where a plurality of ink dots to be ejected on the recording medium do not overlap with each other as much as possible in order to suppress the image quality deterioration described above, the surface unevenness of the printed matter becomes small and a low gloss expression There was a problem that it could not be realized.

  An object of the present invention is to provide an image processing that realizes a low gloss expression while suppressing the narrowing of the width of the density that can be expressed on a recording medium of an image to be formed.

In order to solve the above problems, an image processing apparatus according to the present invention is an image processing apparatus that generates data for forming an image by recording at least colored ink on a recording medium, and includes a plurality of pixels. And input means for inputting image data representing an image, and for each pixel of the image based on the image data, a first recording amount used for recording in which the colored ink is juxtaposed on the recording medium, and the recording medium First determining means for determining at least one of the second recording amount used for recording in which the colored ink is stacked at the discrete position, and the first recording amount and the second recording amount on the recording medium. said generating means for generating arrangement data indicating an arrangement of colored inks, has, in the high density portion of the image is the product of the colored ink in the discrete positions on said recording medium A layer formed by printing overlapping the layer formed by the recording juxtaposing the colored ink onto the recording medium, but characterized by the presence in the same region.

  It is possible to provide image processing that realizes low gloss expression while suppressing the narrowing of the width of the density that can be expressed on the recording medium of the image to be formed.

FIG. 2 is a schematic cross-sectional view showing the arrangement of ink dots for forming an image on a recording medium. FIG. 1 is a block diagram showing a configuration example of an information processing apparatus 100 in the present embodiment. FIG. 2 is a block diagram showing an example of the logical configuration of the image processing apparatus 200 and the printer 104 in the first embodiment. FIG. 8 is a block diagram showing an example of the logical configuration of the image processing apparatus 200 and the printer 104 in the second embodiment. FIG. 12 is a block diagram showing an example of the logical configuration of the image processing apparatus 200 and the printer 104 in the third embodiment. FIG. 14 is a block diagram showing an example of the logical configuration of the image processing apparatus 200 and the printer 104 in the fourth embodiment. FIG. 2 is a diagram showing an example of a color separation LUT in the present embodiment. FIG. 2 is a diagram showing an example of the configuration of a recording head in the present embodiment. 3 is a flowchart showing image processing of the image processing apparatus 200 in the present embodiment. 6 is a flowchart showing recording amount data distribution processing in the present embodiment. 16 is a flowchart showing Scatter halftone processing in the recording position determination processing in the first to sixth embodiments. FIG. 5 is a view showing an example of ink dot recording positions determined by Scatter halftone processing in the present embodiment. 5 is a flowchart showing Cluster halftone processing in recording position determination processing in the present embodiment. FIG. 5 is a diagram showing an example of dot pattern data used by Cluster halftone processing in the present embodiment. FIG. 14 is a block diagram showing an example of the logical configuration of the image processing apparatus 200 and the printer 104 in the fifth embodiment. FIG. 16 is a block diagram showing an example of the logical configuration of the image processing apparatus 200 and the printer 104 in the sixth embodiment. 16 is a flowchart showing recording amount data distribution processing in the fifth embodiment. FIG. 18 is a diagram showing an example of a color separation LUT in Embodiment 6. FIG. 16 is a flowchart showing Scatter halftone processing in the recording position determination processing in Embodiment 7. FIG. FIG. 2 schematically shows a recording head and a mask pattern. FIG. 7 is a view schematically showing the relationship between the ink dot arrangement and the ink dot arrangement distributed for each printing scan.

  First, the ink dot arrangement realized in the present embodiment is shown using the schematic cross-sectional view of the recording medium shown in FIG. In FIG. 1 (a), ink dots are stacked high at a plurality of spaced target positions for driving ink dots on a recording medium, and recording is performed (hereinafter, ink is stacked at discrete positions on the recording medium) An example is also shown. FIG. 1B shows an example in the case where ink dots are recorded at such a position that a plurality of ink dots ejected onto the recording medium do not overlap as much as possible (hereinafter referred to as recording in which the ink is juxtaposed on the recording medium). . Here, the position where they do not overlap as much as possible is a position where recording is performed so that the plurality of ink dots to be ejected do not overlap in a possible range. FIGS. 1 (a) and 1 (b) are diagrams in the high density portion where the recording amount of colored ink is large.

  As shown in FIG. 1A, by performing recording in which the ink is stacked at discrete positions on the recording medium, it is possible to form an image with large unevenness on the surface of the printed matter. The light reflected on the surface of the image with large irregularities is more intense in the diffuse reflection component than in the specular reflection component, so that low gloss expression is possible. However, since the ink coverage is low, image quality deterioration such as deterioration of granularity of an image to be formed or narrowing of the range of expressible density occurs. Here, the ink coverage indicates how much the recording medium is covered by the ink for each area.

  On the other hand, as shown in FIG. 1B, when recording is performed in which colored inks are juxtaposed on a recording medium, image deterioration such as graininess deterioration is suppressed because the ink coverage is high. However, since the surface is a smooth surface without irregularities, the specular reflection component of the incident light is intensified and high gloss is obtained. Therefore, low gloss expressions can not be made.

  Therefore, in the present embodiment, an image of the ink dot arrangement as shown in the schematic cross-sectional view shown in FIG. 1C is formed. As shown in FIG. 1C, in order to improve the ink coverage, a covering layer is formed in which the ink dots are disposed at such a position that the plurality of ink dots to be ejected onto the recording medium do not overlap as much as possible. Here, the covering layer is a layer of ink in which the area on the recording medium is covered by the ink so that paper white is eliminated as much as possible. After forming the covering layer, the colored ink dots are stacked high at a plurality of spaced target positions for driving the ink dots on the recording medium within the recording amount range that can be recorded on the recording medium, and recording is performed. By doing this, an uneven layer having large unevenness is formed on the surface of the printed matter. By realizing such an ink dot arrangement, it is possible to achieve both low gloss expression and high ink coverage.

  When only colored ink is used as shown in FIG. 1 (e), the amount of the ink for reproducing the color indicated by the image data with the coating layer is as described above in the low density portion and the middle density portion. It is not possible to realize a layered structure consisting of layers. Therefore, in the apparatus configuration including only colored ink, low gloss expression and high ink coverage can be achieved at only the high density portion. However, by using a colorless ink in addition to the colored ink, it is possible to realize a layer structure composed of the covering layer and the concavo-convex layer even in the low density portion and the middle density portion. In the configuration provided with only colored ink, as described above, when colored ink dots are not high when stacking colored ink dots high at a plurality of spaced apart target positions for injecting ink dots on the recording medium There is. In this case, by using a colorless ink instead, the difference in the recording amount of the ink for each area expressing the same density on the recording medium is reduced, and the difference in the uneven shape of the print surface according to the density of the image is small. Form an image. An ink dot arrangement that can be realized when using a colorless ink is shown in FIG. In the low-to-medium density region, the colored ink dots are preferentially arranged at positions where the plurality of ink dots ejected onto the recording medium do not overlap with each other as much as possible so that density unevenness in each region becomes small. By realizing the ink dot arrangement for each density area as described above, it is possible to suppress the deterioration of the granularity of the image to be formed and the narrowing of the expressible density width, and it is uniform in all density areas in the image. It becomes possible to realize low gloss expression.

  The embodiments will be described in detail below with reference to the drawings. The following embodiments do not limit the present invention, and all combinations of the features described in the following embodiments are not necessarily essential to the solution means of the present invention. The same components will be described with the same reference numerals.

  Moreover, the image processing apparatus in the following Example 1, Example 2, Example 5, and Example 6 is equipped with four types of colored ink and colorless ink. On the other hand, the image processing apparatus in the third and fourth embodiments includes only four types of colored ink. In the following embodiments, the ink is represented by a single-Kana notation such as cyan, magenta, yellow, black, or clear for each color. In addition, the color of ink or its data is represented by capital letters such as C, M, Y, K, and CL. That is, C is cyan or its data, M is magenta or its data, Y is yellow or its data, K is black or its data, CL is a transparent or colorless (clear) ink data Are respectively represented. The number of inks is not limited to the above example, and in Examples 1, 2, 5 and 6, at least one or more kinds of colored ink and colorless ink may be provided. In the third and fourth embodiments, at least one kind of colored ink may be provided. Also, the colorless ink may have slight color or turbidity as long as it does not affect the density that can be expressed on the recording medium. In the following embodiments, “pixel” is the smallest unit capable of expressing gradation, and is the smallest unit to be subjected to image processing (processing such as color separation to be described later) of multi-bit input data. In the following embodiment, processing is performed every 4 × 4 pixels.

Example 1
An example of the hardware configuration in the present embodiment is shown in the block diagram of FIG. The CPU 1001 in the information processing apparatus 100 executes the OS and various programs stored in the ROM 1002 and the storage unit 105 using the RAM 1003 as a work memory, and controls each unit described later via the system bus 1008. The storage unit 105 is, for example, an HDD, an SSD, or a flash memory connected to the system bus 1008 via the SATA interface (I / F) 1006. The general-purpose I / F 1005 is a serial bus interface such as USB, and is connected with an input device 102 such as a mouse and a keyboard, a general-purpose drive 103 for recording media, a printer 104 and the like. The CPU 1001 loads a program designated by the user via the input device 102 from the storage unit 105 into the RAM 1003, executes the program, and displays a user interface on the display 101 connected to the video card (VC) 1004. The user uses the user interface to select, create, and edit image data and the like to be input in the logical configuration of the image processing apparatus 200 described later. Note that image data or data that is the basis of the image data is stored in the storage unit 105 or the recording medium of the general-purpose drive 103. A network interface card (NIC) 1007 is a network interface for connecting the information processing apparatus 100 to a network such as a wired LAN or a wireless LAN. The program executed by the information processing apparatus 100, image data, or data as a base of the image data may be stored in a server apparatus on the network. The processing and functions of the image processing apparatus 200 described later can be realized by a printer driver, and in this case, the information processing apparatus 100 in which the printer driver is installed functions as the image processing apparatus 200. It is also possible to incorporate the image processing apparatus 200 into the printer 104 as hardware.

  FIG. 3 shows a detailed logical configuration of the image processing apparatus 200 and the printer 104 in the present embodiment. The image processing apparatus 200 and the printer 104 are connected by a printer interface or circuit. The image processing apparatus 200 receives image data to be printed from the image data input terminal 201, and stores the image data in the image data buffer 202. The image data is data representing a 3-channel color image of 8 bits each for RGB.

  The image data conversion unit 2041 in the recording amount determination unit 204 converts the image data stored in the image data buffer 202 into recording amount data indicating the recording amount of ink to be recorded on the recording medium. Hereinafter, this conversion process is called color separation process. In color separation processing, a color separation LUT (Look Up Table) 203a, which is a table holding input signal values as shown in FIG. 7A and the corresponding recording amounts of ink, and general interpolation processing are used. The input signal value is converted into recording amount data of each ink. The color separation LUT is stored in the ROM 1002. After that, the recording amount data distribution unit 2042 distributes the recording amount data of each ink to Scatter recording amount data and Cluster recording amount data. The distribution is performed based on the relationship between the recording amount and the ink coverage on the recording medium so that the colored ink covers as much as possible the area on the recording medium where the ink dots are to be ejected. The Scatter recording amount data indicates the recording amount used to form the covering layer (hereinafter referred to as the Scatter recording amount), and the Cluster recording amount data indicates the recording amount used to form the uneven layer (hereinafter referred to as the Cluster recording amount). The recording amount data of the colorless ink (CL) is Cluster recording amount data because it is used for forming the concavo-convex layer as described in the ink dot arrangement realized in the above-mentioned embodiment. Further, in order to reduce the difference in the uneven shape on the surface of the printed matter due to the density of the image to be recorded, the Cluster recording amount indicated by the Cluster recording amount data is set to a constant recording amount regardless of the input signal value. Recording amount data obtained by converting the image data is sent to the recording position determination unit 205.

  The recording position determination unit 205 determines on which position on the recording medium the ink dots are to be recorded based on the recording amount data input from the recording amount determination unit 204, and generates image formation data. The recording position determination unit 205 includes three processing units, a Scatter halftone processing unit 2051, a Cluster halftone processing unit 2052, and a merge processing unit 2053. The Scatter halftone processing unit 2051 performs halftone processing using Scatter recording amount data, and the Cluster halftone processing unit 2052 performs halftone processing using Cluster recording amount data to obtain arrangement data. The merge processing unit 2053 merges (merges) the obtained two pieces of arrangement data to generate image formation data. The generated image formation data is stored in the image formation data buffer 206. The distribution of the recording amount data and the method of generating the image formation data from the recording amount data will be described in detail later. The image forming data stored in the image forming data buffer 206 is output from the output terminal 207 to the printer 2. The output terminal 207 is configured by a general-purpose I / F.

  In the printer 104, ink dots are formed on the basis of the image formation data generated by the image processing apparatus 200 received from the input terminal 1047 by moving the recording head 1041 in a direction perpendicular or parallel to the conveyance direction of the recording medium 1042. Record on a recording medium. In the present embodiment, an inkjet type is used as the recording head 1041. The recording head 1041 has a plurality of recording elements (nozzles). The moving unit 1043 moves the recording head 1041 under the control of the printer control unit 1044. The conveyance unit 1045 conveys the recording medium under the control of the printer control unit 1044. In this embodiment, a multipass printing method is used in which printing is performed a plurality of times by the printing head 1041 on a printing medium to complete an image. In addition, although the movement of the recording head is a reciprocating operation, a so-called bidirectional printing method is used in which the recording operation is performed in both the forward scanning and the backward scanning. Instead of bidirectional printing, unidirectional printing may be used. The ink selection unit 1046 selects ink from among the inks mounted on the recording head 1041 based on the image formation data of each ink formed by the image processing apparatus 200.

  FIG. 8 is a diagram showing the configuration of the recording head 1041 in the present embodiment. In the present embodiment, five types of ink of C, M, Y, K, and CL are mounted on the recording head 1041. Although FIG. 8 shows a configuration in which a plurality of nozzles are arranged in a line in the moving direction of the head, the number and arrangement of the nozzles are not limited to this example. For example, a plurality of the same discharge amount nozzles may be provided, or a plurality of nozzles may be arranged in a zigzag. In addition, the recording medium 1042 may be arranged in a line in the conveyance direction.

Next, the image forming process of the CPU 1001 in the image processing apparatus 200 will be described using the flowchart of FIG. (Hereinafter, each step (step) is indicated by adding an S in front of the reference numeral.)
In S 201, image data is input from the image data input terminal 201 and stored in the image data buffer 202. In step S202, the RGB image data stored in the image data buffer 202 is converted to 5-plane recording amount data of C, M, Y, K, and CL with reference to the color separation LUT 203a. In the present embodiment, the recording amount data after the color separation processing treats each pixel data as 8-bit data of 0 to 255. The number of bits may be determined by an arbitrary number of gradations, and is not limited to the above example. In S203, based on the relationship between the recording amount based on the recording amount data of four planes excluding the recording amount data of colorless ink and the ink coverage on the recording medium, recording amount data of each ink is scatter recording amount data and Cluster recording Distribute to volume data. Further, as described above, the recording amount data of the colorless ink is all Cluster recording amount data.

  In S204, it is determined at which position on the recording medium the ink dots of the recording amount based on the recording amount data are to be recorded. The position of the ink dot to be recorded is determined for each ink for each printing scan, and is treated as 1 bit data indicating whether or not the ink dot is to be recorded, for each pixel. In this embodiment, in order to describe an example in which ink dots are recorded by eight recording scans, positions of ink dots for recording a total of 32 patterns for eight colors per color and four colors of CMYK are determined. The positions of ink dots to be recorded are determined by sequentially selecting and processing the recording amount data of each ink. The position of the ink dot to be recorded is determined based on the recording amount data of 8 planes of the corresponding Scatter recording amount data and Cluster recording amount data. First, in S2041, based on Scatter recording amount data used for forming the covering layer, arrangement data for recording ink dots by only the first four recording scans is generated. Hereinafter, the processing in step S2041 is referred to as scatter halftone processing. After that, in S2042, based on Cluster recording amount data used for forming the concavo-convex layer, arrangement data for recording ink dots by only the latter four recording scans is generated. After the two arrangement data are generated, the positions of ink dots to be recorded in total of eight patterns are determined by merging them. Hereinafter, the process in S2042 is referred to as Cluster halftone process. Incidentally, in the merge process, the first four times of arrangement data and the second half of arrangement data are integrated in a connected manner. As described above, recording based on the Scatter recording amount data is performed by the first four recording scans, and recording based on the Cluster recording amount data is performed by the second half recording scans. As a result, it is possible to record ink dots on the basis of Cluster recording amount data on ink dots recorded based on Scatter recording amount data. The method of determining the position of the ink dot to be recorded in S2041 and S2042 will be described in detail later. In S205, based on the positions of ink dots to be printed in each printing scan determined for each ink, image forming data of an arbitrary size such as the entire image or the bandwidth for each printing scan is generated, and an image forming data buffer is generated. Store in 207.

  The printer 104 receives the image formation data from the input terminal 1047, and after the ink selection unit 1046 selects an ink compatible with the image formation data, image formation is started. In image formation, while the recording head 1041 moves in a direction perpendicular or parallel to the moving direction of the recording medium 1042, each nozzle is driven at a constant driving interval to form an image on the recording medium. The recording medium 1042 is conveyed by the conveyance unit 1045 for each scan by an amount necessary to form an image.

  Thus, a series of image formation processing on image data is completed. Next, the details of each process will be described in the order of S203, S2041, and S2042.

  The recording amount data distribution (S203) will be described in detail below using the flowchart of FIG. In S2031, a total recording amount X is calculated by adding the recording amounts of the respective inks. In S2032, the recording amount P at which the ink coverage rate is 100% held in advance is compared with the total recording amount X calculated in S2031. The recording amount P at which the ink coverage rate is 100% is a recording amount necessary when arranging dots in all pixels. As a result of comparison, when the total recording amount X is less than the recording amount P, the recording amount corresponding to the input signal value can not cover 100% of the area where the colored ink strikes the ink dots on the recording medium. It is determined that the scatter recording amount is set (S2033). On the other hand, when the total recording amount X exceeds the recording amount P, since it is possible to further form the unevenness after covering 100% of the area on the recording medium where the colored ink strikes the ink dots, S2034 or later Go to the process of

In S2034, the recording amount for each ink is compared. As a result of comparison, an ink with a small recording amount is selected with priority, and the processing from S2035 to S2037 is repeated for each selected ink. The reason why the ink having a small recording amount is preferentially used to form the covering layer is to prevent the color gamut from being narrowed. During the repetitive processing, when the condition of S2036 is satisfied, the repetitive processing ends, and the process proceeds to S2038. At S2035, based on the recording amount X _i (i = C, M, Y, K) of the selected ink and the total amount Xs of the recording amount which has already been determined as the Scatter recording amount, temporary calculation is made from (Expression 1) below The recording amount Xtmp is calculated.

X tmp = X _i + X s (Equation 1)
In S2036, the temporary recording amount Xtmp is compared with the recording amount P. As a result of the comparison, the temporary storage amount Xtmp cases below the recording amount P, the process proceeds to S2037, it is determined that all Scatter recording amount of recording amount _{X i} of the selected ink. On the contrary, if it exceeds, the process proceeds to S2038, and using the following (Equation 2) and (Equation 3), the scattered recording amount of the selected ink, X _i s, and the Cluster recording amount of X _i c are determined Do.

X _i c = X tmp − P (Equation 2)
X _i s = X _i −X _i c (Equation 3)
Finally, in S2039, upon treatment S2035～S2037, when the ink was not selected exists, determines its ink all recording amount as Cluster recording amount _{X i} c.

  By the above recording amount data distribution (S203), recording amount data of each color ink can be distributed to Scatter recording amount data and Cluster recording amount data.

  Next, the scatter halftoning process (S2041) will be described in detail with reference to the flowchart of FIG. The scatter halftoning process (S2041) is a process of determining the positions of the ink dots to be recorded in order to arrange the ink dots in such a position that the plurality of ink dots ejected onto the recording medium do not overlap with each other as much as possible. By performing recording at the position determined by this processing, it is possible to suppress the image quality deterioration due to the decrease in the ink coverage.

  In S20411, the dither matrix to be held is input in advance. The dither matrix is two-dimensional data in which a threshold is stored for each pixel as indicated by 901 in FIG. A value of 0 to M-1 is stored in each pixel as a threshold, and the arrangement of the threshold is determined using a known blue noise mask. M is determined by the size of the dither matrix. In this embodiment, since the size of the dither matrix is 4 × 4 pixels, M is 16 (= 4 × 4).

  In S20412, a dot number ratio Rp (p = 1 to 8) which is data indicating how to distribute the number of ink dots to be printed in each printing scan is input. In the present embodiment, since the ink dot implantation based on the scatter recording amount data is all performed by the first four recording scans of the total eight recording scans, the dot number ratio Rp shown below is input.

Rp = 1/4 (p = 1 to 4)
Rp = 0 (p = 5 to 8)
In the following S20413 to S20415, the ink is selected in order, and the selected ink is processed for each recording scan. In order to prevent the color gamut from being narrowed, it is preferable that the order of selection of the ink be K → C → M → Y on which an ink having a low transmittance of incident light is a base.

In S20413, it calculates dither total number of dots in the selected ink recorded in the same 4 × 4 region of pixels with a matrix _{901a Ds i (i = C,} M, Y, K) a. Furthermore, based on the total number of dots Ds _i and dot number ratio Rp, and calculates the total number of dots Ds i _p of recording ink selected for each recording scan. Total number of dots Ds _i, when the pixel value at a pixel position indicated by the Scatter recording amount data of the ink chosen (x, y) and the I (x, y), obtained by the following equation (4).

_{Df i = ΣI (x, y} ) / M (f = s, c) ····· ( Equation 4) In other words, the total number of dots Ds _i is, 4 × 4 pixels Scatter recording amount in the data of the ink selected It is a value obtained by dividing the average of the pixel values of the area by M. In the example relating to the K ink of the recording amount data 902 in FIG. 12, Ds _k = 4. Then, it calculates the number of dots Ds _i p in each printing scan. dots Ds _i p of p scan th (p = 1 to 8) is obtained by distributing the total number of dots Ds _i in a ratio defined by the number of dots ratio Rp of the recording scans each. In the example shown in 903 of FIG. 12, the number of dots Ds i _p in each recording scan is as follows.

Ds _k p = 1 (p = 1 to 4)
Ds _k p = 0 (p = 5 to 8)
Note that since the dot number Dsip for each printing scan needs to be an integer value, as in the case of Dsip = 5, distribution according to the dot number ratio Rp is performed depending on the value of the total dot number Dsip to be printed in the area. Can not do it. In the above case, as described below, the dot numbers are distributed so that the difference between the dot number Dsip and Dsi × Rp in each printing scan is reduced.

Ds _i p = 2 (p = 1)
Ds _i p = 1 (p = 2 to 4)
Ds _i p = 0 (p = 5 to 8)
Further, as described above, the scan where Ds _i p = 2 does not have to be p = 1, and may be anywhere from p = 1 to 4.

In S20414, the threshold value in the dither matrix 901 is compared with M to determine the ink dot arrangement in the recording scan of the selected ink. The determination of the ink dot arrangement is performed by turning on Ds _i p dots in order from the pixel having the smallest threshold value Th (x, y) of the dither matrix 901. For the example shown in FIG. 12, the ink dot arrangement in the first recording scan the K ink, for Ds i p _{= 1,} the ink dot arrangement 903a to ON ink dots of a pixel threshold 0. The state of being ON is a state in which it is decided to put a dot on the pixel. In S20415, M is added to the threshold Th (x, y) of the dither matrix 901 at the position where the ink dot is turned ON in S20414. As described above, the threshold value of the area in which the ink dot is turned on is updated so as to exceed M, and the ink dot arrangement in the next printing scan is determined based on the updated dither matrix. An example of the positions of ink dots to be recorded in the recording scan (1 to 8 times) of the K ink determined on the basis of the recording amount data 902 of the K ink is shown in 903a to h in FIG. As shown in the figure, the positions of the ink dots are determined such that the plurality of ink dots to be ejected onto the recording medium do not overlap with each other as much as possible. Further, as shown in the flowchart of FIG. 11, after the ink dot arrangement of the selected ink is determined, the ink dot arrangement of the other ink is determined using the dither matrix whose threshold value is updated. As a result, the ink dot arrangement of the K ink shown in 903a-h in FIG. 12 and the ink dot arrangement of the C ink shown in 906a-h are obtained. If M ink dots are arranged and all the dither matrix values become M or more, the dither matrix is returned to the initial state, and the process is repeated.

  By the above-described Scatter halftone processing (S2041), arrangement data for the first half of the recording scan is obtained.

  Next, Cluster halftone processing (S2042) will be described in detail using the flowchart of FIG. The cluster halftoning process (S2041) is a process of determining the ink dot arrangement in which colored ink dots are stacked high and recorded at a plurality of spaced apart target positions for driving the ink dots on the recording medium. By performing recording at the position determined by this processing, it is possible to increase unevenness on the surface of the print and realize low gloss expression.

  In S20421, dot pattern data used for each printing scan is input. An example of a dot pattern is shown in a schematic view in FIG. The dot pattern data to be input is two-dimensional data in which the positions and the order of the ink dots to be recorded for each recording scan are defined. The dot pattern data used for printing in each printing scan of FIG. 14A is an example. Usually, a chart in which the number of ink dots to be printed and the ink dot arrangement are controlled in each printing scan is printed, and the chart is observed with a loupe or the like to determine and set in advance a condition that provides the lowest gloss expression. In steps S20422 to S20424, the ink is selected from the respective inks, and the process is repeated until the processing of all the inks is completed.

In S20422, calculated on the basis of the Cluster recording amount data of the ink selected, the total number of dots _{Dc i (i = C, M} , Y, K, CL) and. The calculation of the number of dots is performed using (Equation 4) as in S20413. In S20423, the ink dot recording order is earlier in the dot pattern data entered in S20421, continue to determine the recording position by the total dot number Dc _i min calculated in S20422.

In S20424, the place determined as the recording position in the dot pattern data in S20423 is specified, and the value in the two-dimensional data corresponding to the place is updated with 0. Furthermore, it subtracts the total number of dots Dc _i of ink only selected number updated in 0. If all the values in the two-dimensional data become 0, the two-dimensional data is returned to the initial state, and the process is repeated. In addition, as soon as the total number of dots Dc _i becomes 0, continue to determine the position of the ink dots to select the next ink. When the next ink is selected and the ink dot position is determined, the updated dot pattern is used.

  By the above-described Cluster halftone process (S2042), arrangement data for the last four recording scans are obtained. The two arrangement data generated by the scatter halftoning process (S2041) and the cluster halftoning process (S2402) are merged to determine the positions of the ink dots to be recorded on the recording medium for eight recording scans.

  By performing the process control described above, it is possible to realize an ink dot arrangement with high unevenness and large ink coverage in a region where ink dots are ejected on the recording medium. Furthermore, by using a colorless ink, the difference in the recording amount of the ink when expressing the same density on the recording medium is reduced, and the image having a small difference in the uneven shape of the print surface according to the density of the image is formed. Do. As a result, it is possible to realize uniform low gloss expression in all density regions in the image while suppressing deterioration in graininess of the image to be formed and narrowing of the width of the expressible density.

  In this embodiment, as an example of setting the recording amount P necessary for forming the covering layer for improving the ink coverage by the scatter halftone process, the example of arranging the dots in all the pixels has been described. It is not limited to one example. The recording amount P may be set in consideration of the size of the ink dot when the ink dot is fixed on the recording medium, and the ink diffusion amount diffused (i.e., blurred) in the peripheral area when the ink dot is ejected. As a method of setting the recording amount P in consideration of dot size and bleeding, the surface of a printing chart obtained by printing with ink while changing the recording amount is observed using a microscope or a loupe, and whether or not there is paper white of the recording medium There is a way to judge and identify. For example, when the ink dot size is larger than one pixel, as shown in FIG. 1D, the maximum value of the recording amount by the scatter halftoning process is reduced than usual. By reducing the maximum value of the recording amount, the recording positions of the ink dots to be recorded by the scatter halftoning process are arranged not in all pixels but in thinning out.

  Further, in the present embodiment, the relationship between the ink coverage and the recording amount is measured in advance, and the recording amount P at which the coverage is 100% is held. However, the present invention is not limited to the above example. For example, in order to cope with the fluctuation of the ink ejection amount and the fluctuation of the ink coverage according to the type of the recording medium, the user may be provided with a mechanism capable of calibrating the recording amount P at 100% coverage. In addition, the ink coverage of the recording amount P may not be 100%. For example, if the ink coverage is 80% and graininess is not a problem, the ink coverage of the recording amount P may be lowered to about 80%.

  Moreover, although the example which performs Cluster halftoning processing after performing Scatter halftoning processing was demonstrated in this embodiment, the processing order is not limited to said example. As shown in FIG. 9B, Cluster halftone processing may be performed first. Also, two halftoning may be processed simultaneously.

  Further, in the present embodiment, after the recording position of the colored ink dots on the recording medium is such that the plurality of ink dots to be punched into the recording medium do not overlap with each other as much as possible, the unevenness of the printed matter surface is enlarged. An example using a colorless ink has been described. However, the recording order of the colored ink and the colorless ink is not limited to the above example. For example, by recording the colorless ink on the recording medium prior to the colored ink dots, it is possible to use a control method for inhibiting the penetration of the colored ink dots into the recording medium and further increasing the unevenness on the surface of the printed matter. As described above, in the case of using the effect of the permeation inhibition of the colored ink by the colorless ink, the following processing is performed. First, a color separation LUT having a colorless ink recording amount equal to or more than a predetermined value is prepared for all input signal values, and the dot number ratio Rp used in S20412 is set as follows.

Rp = 0 (p = 1)
Rp = 1/4 (p = 2 to 5)
Rp = 0 (p = 6 to 8)
Further, the dot pattern used in S20421 is changed as shown in FIG. 14B, the recording positions of the ink dots are determined in order from the sixth recording scan in S20423, and the first recording scan is finally selected. By controlling under the conditions described above, it is possible to realize the ink dot arrangement as shown in FIG. 1 (g).

  Further, in the present embodiment, an example is described in which the number of scans recorded by Scatter halftone processing and the number of scans recorded by Cluster halftone processing are equally divided, but the ratio of recording scans is not limited to the above example. For example, in order to realize a lower gloss expression, the number of colored ink dots is increased by piling up colored ink dots at a plurality of spaced apart target positions for driving the ink dots on the recording medium. Therefore, the number of recording scans used in Cluster halftone processing may be increased, and the number of recording scans in Scatter halftone processing may be reduced.

In this embodiment, the color separation LUT 203a holds the recording amount of colorless ink corresponding to the input image data, but the method of determining the cluster recording amount Xc _CL of the colorless ink is not limited to the above example. . Since the total amount Xc _all of Cluster recording amount is constant regardless of the input signal value, for example, held in the color separation LUT (not shown) the recording amount of color ink corresponding to the image data to be input, in the following manner Xc _CL may be calculated. And _{Xc all} held in advance, from Clustter recording amount _Xc i of each ink (i = C, M, Y , K), is calculated using the following Equation (5).

Xc _CL = Xc _all -Xc _C -Xc _M -Xc _Y -Xc _K (Equation 5)
Example 2
Regarding the configuration of the image processing apparatus 200 in the present embodiment, differences from the first embodiment will be described. FIG. 4 is a block diagram showing a detailed logical configuration of the image processing apparatus 200 in the present embodiment. The logical configuration of the image processing apparatus 200 in the present embodiment does not have the recording amount data distribution unit 2042 in the recording amount determination unit 204 in the first embodiment. Further, unlike the first embodiment, the color separation LUT used in the image data conversion unit 2041 is a color separation LUT 203b shown in FIG. 7B.

  Regarding the image processing in the image processing apparatus 200 of the present embodiment, differences from the first embodiment will be described. In the first embodiment, input image data is converted into recording amount data of each ink using a color separation LUT 203a that holds the recording amount of each ink and the input signal value as shown in FIG. 7A. Thereafter, based on the relationship between the recording amount and the ink coverage on the recording medium, the recording position determination unit 205 distributes the recording amount to the Scatter recording amount and the Cluster recording amount, and determines the recording position of the ink dot. did. In the present embodiment, the color separation LUT 203b holding the correspondence between the input signal value indicated by the image data, the scatter recording amount, and the Cluster recording amount is created in advance by performing recording amount data distribution (S203) in the first embodiment. Keep it. By using the LUT 203 b in the image data conversion unit 2041, image data can be converted into Scatter recording amount data and Cluster recording amount data of each ink without performing recording amount data distribution (S 203) at the time of image processing. That is, in FIG. 9, after the color separation processing S202 is performed, the processing of recording amount data distribution S203 is not performed, and the processing proceeds to processing of recording position determination S204. The image processing of the present embodiment is different from the image processing of the first embodiment only in whether or not the recording amount data distribution (S203) in FIG. 2 described above is performed at the time of the image processing. The description is omitted.

  Also in the present embodiment, as in the first embodiment, it is possible to realize the ink dot arrangement with high unevenness and large ink coverage in the region where the ink dots are ejected on the recording medium. Furthermore, by using a colorless ink, the difference in the recording amount of the ink when expressing the same density on the recording medium is reduced, and the image having a small difference in the uneven shape of the print surface according to the density of the image is formed. Do. As a result, it is possible to realize uniform low gloss expression in all density regions in the image while suppressing deterioration in graininess of the image to be formed and narrowing of the width of the expressible density.

[Example 3]
Although Example 1 and Example 2 explained the example using four kinds of colored ink and colorless ink, this example is an example using only four kinds of colored ink. In particular, the difference from Example 1 is that the colorless ink is not used.

  Regarding the configuration of the image processing apparatus 200 in the present embodiment, differences from the first embodiment will be described. FIG. 5 is a block diagram showing the logical configuration of the image processing apparatus 200 in the present embodiment. The logical configuration of the image processing apparatus 200 in the present embodiment is different from that of the first embodiment, and the color separation LUT used in the image data conversion unit 2041 is a color separation LUT 203c shown in FIG. 7C.

  The difference from the first embodiment in the image processing in the image processing apparatus 200 of the present embodiment is that a LUT 203c which does not hold recording amount data of colorless ink is used. By referring to the LUT 203c, the same image processing as that of the first embodiment is performed using only the recording amount data of the colored ink converted from the image data in the color separation processing (S202).

  In the present embodiment, since colorless ink is not used, FIGS. 1 (f) and 1 (g) are not realized among the ink dot arrangements realized in the above-described present embodiment. However, by realizing the arrangement as shown in FIG. 1E, it is possible to achieve both low gloss expression and high ink coverage, particularly in the high density portion.

Example 4
The present embodiment is an embodiment using only four types of colored inks as in the third embodiment. In particular, the difference from Example 2 is that the colorless ink is not used.

  Regarding the configuration of the image processing apparatus 200 in the present embodiment, differences from the second embodiment will be described. FIG. 6 is a block diagram showing the logical configuration of the image processing apparatus 200 in the present embodiment. The configuration of the image processing apparatus 200 in this embodiment is different from that of the second embodiment, and the color separation LUT used in the image data conversion unit 2041 is a color separation LUT 203 d shown in FIG. 7D.

  The difference between the second embodiment and the second embodiment of the image processing in the image processing apparatus 200 of the present embodiment is that a LUT 203 d which does not hold recording amount data of colorless ink is used. By referring to the LUT 203d, the same image processing as in the first embodiment is performed using only the recording amount data of the colored ink converted from the image data in the color separation processing (S202).

  In the present embodiment, since colorless ink is not used, FIGS. 1 (f) and 1 (g) are not realized among the ink dot arrangements realized in the above-described present embodiment. However, by realizing the arrangement as shown in FIG. 1E, it is possible to achieve both low gloss expression and high ink coverage, particularly in the high density portion.

[Example 5]
Regarding the configuration of the image processing apparatus 200 in the present embodiment, differences from the first embodiment will be described. FIG. 15 is a block diagram showing the detailed logical configuration of the image processing apparatus 200 in the present embodiment. In the first embodiment, first, RGB 3-channel data having information on color is input as input data. Then, an example of distributing the CMYK recording amount data obtained by color separation processing using the input data to the Scatter recording amount data and the Cluster recording amount data using the recording amount P at which the ink coverage on the recording medium is 100% Said. The recording amount P where the ink coverage on the recording medium is 100% corresponds to the scatter recording amount shown in the color separation LUT 203a of FIG. 7A, and the maximum value of the scatter recording amount of each ink is 100. In this embodiment, 4-plane image data including gloss data indicating the intensity of gloss in addition to RGB 3-channel data is used as input data. The maximum value of the scatter recording amount of each ink is selected from Pl, Pm, and Ph, which are 100, 150, and 255, according to the gloss intensity indicated by the input data.

  FIG. 18 shows a flowchart related to recording amount data distribution (S203). In the process of the present embodiment, only the process of S2030 in the recording amount data distribution (S203) is different from the process of the first embodiment, so the process of S2030 will be described below.

  In S2030, the maximum value of the recording amount used for the covering layer on the recording medium is selected from Pl, Pm, and Ph in accordance with the gloss data indicating the gloss strength. The gloss data is 8 bit data and has a value of 0 to 255. The area where the value of gloss data is small is low gloss and the area where the value is high is high gloss. Select Pl when the value of gloss data is 0 to 85, select Pm for 86 to 170, and Ph for 171 to 255. select.

  Also in the present embodiment, since processing is performed for each 4 × 4 pixel area as in the first embodiment, the maximum value of the recording amount used for the covering layer is selected for each 4 × 4 pixel area. Therefore, in addition to the fact that low gloss expression can be realized as in Example 1, in the region where high gloss is desired, the ink forming the covering layer is increased and the ink forming the concavo-convex layer is reduced, thereby making the asperity on the printed matter surface. Smooth and close to express high gloss. Furthermore, in the region where intermediate gloss between low gloss and high gloss is desirable, the recording amount of the ink forming the uneven layer is an intermediate value between low gloss and high gloss, and the unevenness of the printing surface is intermediate between high gloss and low gloss. It becomes possible to express middle gloss by doing.

  In the present embodiment, an example of selecting from three types of low gloss, medium gloss, and high gloss has been described, but the present invention is not limited to the above example. If it is desired to control gloss more finely, the recording amount may be maintained such that the ink coverage of the area into which three or more types of ink dots are to be ejected in accordance with the gloss data is 100%. Alternatively, an intermediate gloss expression may be realized by holding the two states of low gloss and high gloss and controlling the area ratio of the two states.

[Example 6]
Regarding the configuration of the image processing apparatus 200 in the present embodiment, differences from the second embodiment will be described. FIG. 16 is a block diagram showing a detailed logical configuration of the image processing apparatus 200 in the present embodiment. In the second embodiment, an example has been described in which RGB 3-channel data having information on color is input as input data, and image data is distributed to Scatter recording amount data and Cluster recording amount data for each ink using a color separation LUT. In this embodiment, 4-plane image data including gloss data indicating the intensity of gloss in addition to RGB 3-channel data is used as input data. The LUT to be used is selected from LUTs for high gloss, medium gloss and low gloss according to the gloss intensity indicated by the input data. The color separation LUTb, the color separation LUTe, and the color separation LUTf shown in FIGS. 7B, 17A, and 17B respectively represent a low gloss LUT, a medium gloss LUT, and a high gloss LUT. The color separation LUTb, the color separation LUT 203e, and the color separation LUTf are created in advance by performing recording amount data distribution (S203) in the fifth embodiment.

  Also in the present embodiment, since processing is performed for each 4 × 4 pixel area as in the second embodiment, the LUT is selected for each 4 × 4 pixel area. Therefore, in addition to the low gloss expression being realized as in the second embodiment, the high gloss expression is obtained in the area where high gloss is desired, and the intermediate gloss expression is possible in the area where intermediate gloss between low gloss and high gloss is desired.

  In the present embodiment, an example of selecting from three types of low gloss, medium gloss, and high gloss has been described, but the present invention is not limited to the above example. When it is desired to control gloss more finely, three or more types of LUTs corresponding to the gloss may be held.

[Example 7]
Calculates the number of dots Ds _i p in each recording scan based on the total number of dots Ds _i dot count ratio Rp to be recorded in the area from the Examples 1 to 6 In Scatter recording amount data, the dot number Ds _i p Accordingly, an example has been described in which the ink dot arrangement is determined for each recording scan. This example is an example of determining the ink dot arrangement corresponding to the total number of dots Ds _i, distributes the determined ink dots arranged in the ink dot placement of the recording scans each. In particular, the difference from the first to sixth embodiments is the procedure of the process of determining the ink dot arrangement for each printing scan from the scatter recording amount data in the scatter halftoning process. The description is the same as in the first to sixth embodiments except for the scatter halftoning process.

  FIG. 19 is a flowchart showing Scatter halftone processing in the recording position determination processing in the present embodiment.

  Since S20411 is the same processing as that of the first embodiment, the description will be omitted. In the following S20419 to S20421, the ink is sequentially selected as in the first embodiment, and the ink dot arrangement for each recording scan is determined for the selected ink.

In S20419, was treated in the same manner as S20413, the total number of dots in the selected ink for recording in the same 4 × 4 region of pixels and the dither matrix 901a from Scatter recording amount data _{Ds i (i = C, M} , Y, K Calculate).

In S20420, the threshold value in the dither matrix 901 is compared with M to determine the ink dot arrangement of the selected ink. The determination of the ink dot arrangement is performed by turning on Ds _i dots in order from the pixel having the smallest threshold value Th (x, y) of the dither matrix 901. For example, the ink dot arrangement in the case of Ds = 8 is shown in FIG. The dots that are turned on are shown in black, and the dots that are not in white.

  In S20421, a mask pattern 2001, which is data indicating how to distribute the ink dot arrangement of the selected ink for each printing scan, is input. The ink dot arrangement determined in the mask pattern 2001 and S20420 is compared, and is distributed to the ink dot arrangement of each recording scan. First, the mask pattern 2001 will be described with reference to FIG.

  FIG. 20 schematically shows the mask pattern and the recording head. Reference numeral 2000 denotes a recording head, which has 32 nozzles for simplicity. The nozzles are divided by the number of printing scans. For example, when the number of printing scans is eight, as shown in FIG. 20, it is divided into first to eighth eight nozzle groups. Reference numeral 2001 denotes a mask pattern (recording pattern), and a unit area where each nozzle performs recording is shown in black. The patterns recorded by the respective nozzle groups are in a relation of interpolation with each other. When these patterns are superimposed, recording of an area corresponding to a 4 × 4 unit area is completed. Each pattern shown in 2002 to 2009 shows how an image is completed by repeating recording scanning. Every time each printing scan is completed, the printing medium is conveyed by the width of the nozzle group in the direction of the arrow in the figure. Therefore, in the same area (area corresponding to the width of each nozzle group) of the recording medium, an image is completed only by eight recording scans.

  In the present embodiment, a mask pattern is used in which four dots are uniformly turned on in all printing scans, but the present invention is not limited to the above example. The number of dots to be recorded may be determined in consideration of the landing accuracy for each nozzle. For example, 1 dot in the first nozzle group, 3 dots in the second nozzle group, 5 dots in the third nozzle group, fourth nozzle group It may be uneven as in 7 dots.

The mask pattern 2001 for each nozzle group described above is compared with the ink dot arrangement determined in S20420, and the process of turning on the dots turned on in each other pattern is performed, and the processed result is the ink dot arrangement of each recording scan I assume. That is, the result of processing the first nozzle group and the ink dot arrangement determined in S20420 is the ink dot arrangement in the first recording scan. Further, the result of processing the second nozzle group and the ink dot arrangement determined in S20420 is taken as the ink dot arrangement in the second recording scan. The description after the third recording scan is omitted because it is the same. 21 (b), (c) and (d) show the results of applying the mask pattern 2001 to FIG. 21 (a) and distributing to the ink dot arrangement for each printing scan. FIG. 21B shows an example of ink dot arrangement in the first recording scan, FIG. 21C shows an example of ink dot arrangement in the second recording scan, and FIG. 21D shows an example of ink dot arrangement in the third to eighth recording scans. ing. Through the above process, to determine the ink dot arrangement corresponding to the total number of dots Ds _i, it is possible to realize the processing for distributing the determined ink dots arranged in the ink dot placement of the recording scans each.

  As described above, also in the present embodiment, as in the first to sixth embodiments, it is possible to realize the ink dot arrangement with high unevenness and large ink coverage in the area where the ink dots are ejected on the recording medium. Furthermore, in addition to the low gloss expression being realized as in the first to sixth embodiments, the control of stopping the use of the nozzle and the non-ejection nozzle with poor impact position accuracy can be easily performed by switching the mask pattern. It becomes possible.

  In the present embodiment, an example in which the number of dots in the vertical direction of the dither matrix and the number of dots in the nozzle group coincide with each other has been described, but the present invention is not limited to the above example. Even when the numbers of dots do not match each other, the data of a small number of dots may be processed by determining the correspondence by repeatedly referring from the lowermost line to the uppermost line.

[Other embodiments]
The present invention supplies a program that implements one or more functions of the above-described embodiments to a system or apparatus via a network or storage medium, and one or more processors in a computer of the system or apparatus read and execute the program. Can also be realized. It can also be implemented by a circuit (eg, an ASIC) that implements one or more functions.

100 information processing apparatus 104 printer 200 image processing apparatus 202 image data buffer 203 color separation LUT
204 Recording amount determination unit 205 Recording position determination unit 206 Image formation data buffer

Claims (19)

An image processing apparatus for generating data for forming an image by recording at least colored ink on a recording medium, comprising:
Input means for inputting image data representing an image including a plurality of pixels;
Based on the image data, for each pixel of the image, using the first recording amount used for recording in which the colored ink is juxtaposed on the recording medium, and using the recording in which the colored ink is stacked at the discrete position on the recording medium First determining means for determining at least one of the second recording amount;
Generating means for generating arrangement data indicating the arrangement of the colored ink on the recording medium based on the first recording amount and the second recording amount;
In the high density portion of the image, a layer formed by recording in which the colored ink is stacked at discrete positions on the recording medium, a layer formed by recording in which the colored ink is juxtaposed on the recording medium, An image processing apparatus characterized in that The first determination means determines the first recording amount, which is the recording amount of the colored ink, and the second recording amount, which is the recording amount of the colored ink and the colorless ink,
The generation means generates arrangement data indicating arrangement of the colored ink and the colorless ink on the recording medium based on the first recording amount and the second recording amount. The image processing apparatus according to claim 1.   The image processing apparatus according to claim 2, wherein the second recording amount is a recording amount at which the recording amount at each of the discrete positions becomes constant in the image. The input means further inputs gloss data indicating gloss intensity for each area of the image;
The first determining means determines the first recording amount and the second recording amount based on the image data and the gloss data. The image processing apparatus according to claim 1. The image processing apparatus further comprises second determination means for determining a total recording amount obtained by combining the first recording amount and the second recording amount based on the image data.
The first determining unit determines the first recording amount and the second recording amount based on a ratio of the first recording amount to the second recording amount in the total recording amount, the total recording amount, and the second recording amount. The image processing apparatus according to any one of claims 1 to 4, characterized in that: The first determination means determines the first recording amount and the second recording amount so that the ratio of the first recording amount to the second recording amount increases as the color ink having a smaller total recording amount decreases. The image processing apparatus according to claim 5 , wherein:   The first determining means determines the maximum value of the first recording amount based on the size of the ink dots on the recording medium or the ink diffusion amount to the peripheral area by overlapping the ink dots. The image processing apparatus according to any one of claims 1 to 6.   The first determination means holds in advance a table representing the relationship between the first recording amount and the second recording amount, and refers to the table to obtain the first recording amount and the second recording amount. The image processing apparatus according to any one of claims 1 to 7, wherein the ratio is determined. The first determining means determines a ratio between the first recording amount and the second recording amount based on a relationship between the total recording amount and the ink coverage on the recording medium according to the total recording amount. The image processing apparatus according to claim 5 or 6 , wherein the determination is made.   The first determining unit distributes the total recording amount to the first recording amount and the second recording amount based on a ratio between the first recording amount and the second recording amount. 10. The image processing apparatus according to claim 9, wherein one recording amount and the second recording amount are determined.   The first recording amount is a recording amount of ink for covering the recording medium, and the second recording amount is a recording amount of ink for adding unevenness to the surface of the image. 11. An image processing apparatus according to item 10.   When the first ink and the second ink having a lower transmittance than the first ink are stacked on the recording medium, the second ink is recorded below the first ink. The image processing apparatus according to any one of claims 1 to 11.   A covering layer is formed by performing recording based on first arrangement data for arranging the colored ink side by side on the recording medium using the first recording amount, and using the second recording amount 13. The image forming apparatus according to claim 1, further comprising: a forming unit configured to form a concavo-convex layer by performing recording based on second arrangement data for arranging the colored inks in a stacked manner on the recording medium. An image processing apparatus according to any one of the preceding claims.   The image processing apparatus according to claim 13, wherein the forming unit forms the uneven layer after forming the covering layer.   A covering layer is formed by performing recording based on first arrangement data for arranging the colored ink side by side on the recording medium using the first recording amount, and using the second recording amount It further comprises forming means for forming a concavo-convex layer by performing recording based on second arrangement data for arranging at least one of the colored ink and the colorless ink in a stacked manner on the recording medium. The image processing apparatus according to claim 2.   The image processing apparatus according to claim 15, wherein the forming unit forms the uneven layer after forming the covering layer. A printer for forming an image including at least two layers by recording at least colored ink on a recording medium, comprising:
Input means for inputting image data representing the density of the image;
A first layer is formed by recording in which the colored ink is juxtaposed on the recording medium based on the image data, and a second layer is formed by recording in which the colored ink is stacked at discrete positions on the recording medium Means, and
The printer according to claim 1, wherein the forming unit forms the first layer and the second layer in the same area in a high density portion of the image. An image processing method of an image processing apparatus for generating data for forming an image by recording at least colored ink on a recording medium, comprising:
An input step of inputting image data representing an image including a plurality of pixels;
Based on the image data, for each pixel of the image, using the first recording amount used for recording in which the colored ink is juxtaposed on the recording medium, and using the recording in which the colored ink is stacked at the discrete position on the recording medium A determination step of determining at least one of the second recording amount;
Generating arrangement data indicating arrangement of the colored ink on the recording medium based on the first recording amount and the second recording amount;
In the high density portion of the image, a layer formed by recording in which the colored ink is stacked at discrete positions on the recording medium, a layer formed by recording in which the colored ink is juxtaposed on the recording medium, An image processing method characterized in that   The program for functioning a computer as each means of the image processing apparatus as described in any one of Claims 1-12.

Images