JP6904841B2 - Image processing equipment, recorded data generation methods, recording equipment, and programs - Google Patents

Description

The present invention relates to an image processing device, a recorded data generation method, a recording device, and a program.

An inkjet recording apparatus is known that forms an image on a recording medium by ejecting ink while scanning a recording head having a row of ejection ports in which a plurality of ejection ports for ejecting ink are arranged with respect to a recording medium. ing.

Some inkjet recording devices use a recording head having a discharge port for discharging droplets having different discharge amounts, and small dots tend to be frequently used from the viewpoint of improving the graininess.

Patent Document 1 discloses a method of recording a mixture of large dots in a region where the recording rate of small dots exceeds a certain upper limit value. Further, Patent Document 1 discloses a method of recording using only large dots at the maximum gradation value.

Japanese Unexamined Patent Publication No. 2003-94693

The small dots are easily affected by the air flow associated with ink ejection from other ejection port rows. Patent Document 1 does not consider the unevenness of shading caused by the generation of airflow accompanying the discharge from other discharge ports. Further, as described in Patent Document 1, when recording is performed using only large dots at the maximum gradation value, it is reproducible as compared with the case where large dots and small dots are used together at the same recording rate. The concentration will drop.

The present invention has been made in view of the above points, and it is necessary to perform recording in which the unevenness of shading caused by the generation of airflow accompanying the discharge from other discharge port rows is reduced and the reproducible density is improved. With the goal.

In the image processing apparatus according to one aspect of the present invention, a first discharge port row in which discharge ports having a first diameter are arranged and a second discharge port having a second diameter larger than the first diameter are arranged. The first ejection port row group for ejecting the first ink including the second ejection port row and the first ejection port row group adjacent to the first ejection port row group are ejected by the first ejection port row group. An image that generates recording data indicating ejection or non-ejection of each ejection port used in a recording device having a recording head having at least a second ejection port row group for ejecting ink different from the ink ejected. A processing device that ejects image data indicating gradation values to a predetermined pixel region having a predetermined resolution in the first ejection port array based on the acquired image data. The recording rate indicating the proportion of the ink to be printed increases from the first gradation value to the second gradation value larger than the first gradation value as the gradation value increases, and the second floor A generation means for generating the recorded data so that the data decreases when the third gradation value equal to or higher than the adjustment value is exceeded and increases when the fourth gradation value larger than the third gradation value is exceeded. It is characterized by having.

According to the present invention, it is possible to perform recording in which the unevenness of shading caused by the generation of airflow accompanying the discharge from other discharge port rows is reduced and the reproducible density is improved.

It is a perspective view of the inkjet recording apparatus applied in embodiment. It is a schematic diagram which shows the recording control system in embodiment. It is a perspective view of the recording head applied in embodiment. It is a figure which shows the chip surface in the recording head applied in embodiment. It is a perspective view of the vicinity of the discharge port in the recording head applied in embodiment. It is a figure for demonstrating the data processing process in an embodiment. It is a figure which shows an example of the index pattern in an embodiment. It is a figure which shows an example of the index pattern in an embodiment. It is explanatory drawing which shows the correlation of the gradation value and the number of ink ejections in an embodiment. It is a figure which shows an example of the index pattern in an embodiment. It is explanatory drawing which shows the correlation of the gradation value and the number of ink ejections in an embodiment. It is explanatory drawing which shows the correlation of the gradation value and the number of ink ejections in an embodiment. It is explanatory drawing which shows the correlation of the gradation value and the number of ink ejections in an embodiment. It is explanatory drawing which shows the correlation of the gradation value and the number of ink ejections in an embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail, exemplary, with reference to the accompanying drawings. However, the components described in the following embodiments are merely examples, and the scope of the present invention is not limited to them.

<< First Embodiment >>
FIG. 1 is a schematic view showing the configuration of the inkjet recording apparatus 100 according to the present embodiment. FIG. 1 shows a view when the top cover is lifted.

The inkjet recording device (hereinafter, also referred to as a printer or a recording device) 100 in the present embodiment is provided with a carriage 5 that reciprocates (reciprocally scans) along the X direction (intersection direction), and the carriage 5 includes a carriage 5. The recording head 1 described later is mounted. In the present embodiment, the moving speed (scanning speed) of the carriage 5 and the recording head 1 is about 25 inches / sec. By ejecting ink from the recording head 1 while the carriage 5 and the recording head 1 reciprocate, an image recording operation on a recording medium (for example, paper) is performed.

The recording medium is fed from the paper feed tray of the printer and conveyed in the sub-scanning direction intersecting the X direction. The transport speed of the recording medium in this embodiment is about 5 inches / sec.

In the present embodiment, the scanning of the recording head 1 and the transfer of the recording medium as described above are alternately repeated to complete the recording on one recording medium. In this embodiment, a so-called one-pass recording method that completes recording in one scan for a unit area on a recording medium may be used, or recording is completed in a plurality of scans for a unit area. A so-called multipath recording method may be used.

Further, the thickness of the paper used in this embodiment is about 0.3 mm, and the distance in the height direction between the recording head 1 and the paper in that case is about 1.0 mm. A scanner 4 for capturing a recorded image is provided on the upper part of the printer, and the scanner 4 is integrated with the upper cover of the printer.

FIG. 2 is a block diagram showing a schematic configuration of a control system in the recording device 100 according to the present embodiment. The main control unit 200 includes a CPU 201 that executes processing operations such as calculation, selection, determination, and control. Further, the main control unit 200 includes a ROM 202 for storing a control program or the like to be executed by the CPU 201, a RAM 203 used as a buffer for recorded data, an input / output port 204, and the like. Then, drive circuits 205, 206, 207, and 208 such as a transfer motor (LF motor) 209, a carriage motor (CR motor) 210, a recording head 1, and an actuator in the cutting device 213 are connected to the input / output port 204. ing. Further, the main control unit 200 is connected to the PC 212 which is a host computer via the interface circuit 211.

<Recording head>
FIG. 3 is a perspective view showing the recording head 1 used in the present embodiment. In the recording head 1 of the present embodiment, the ink supply unit 2 and the ink ejection unit 3 are integrally configured. The ink supply unit 2 is provided with a holding body 2A that holds an ink tank (not shown) for supplying ink.

The ink ejection unit 3 is provided with a chip (Bk chip) 10 for ejecting black pigment ink and a chip (Cl chip) 20 for ejecting dye ink, which will be described later. In the following description, the Cl chip 20 will be focused on.

FIG. 4 is an enlarged view of the Cl chip 20 in the recording head 1 in the present embodiment. Further, FIG. 5 is a diagram for explaining the internal configuration of each discharge port row group of the Cl chip 20 in the present embodiment.

In the Cl chip 20 of the present embodiment, a total of eight common liquid chambers 21 connected to the ink supply unit 2 are formed, and one ejection port row group LG is formed in one common liquid chamber 21. There is. Each common liquid chamber 21 extends in the Y direction intersecting the X direction. The row direction of the discharge port row group LG extends in the Y direction as in the common liquid chamber 21. Hereinafter, when each discharge port row group is collectively referred to, or when individual discharge port row groups are not distinguished, it is referred to as a discharge port row group LG, and when referring to an individual discharge port row group, it is referred to as LG (). do. In the parentheses of this "LG ()", the alphabets C, M, Y, K, and LB corresponding to the ink are entered. C stands for cyan, M stands for magenta, Y stands for yellow, K stands for black, and LB stands for light blue.

Each discharge port row group LG is composed of a plurality of discharge port rows L, and the diameters (discharge port diameters) of the discharge ports arranged in the discharge port rows are different for each discharge port row group.

Each discharge port in the Cl chip 20 is opened in a discharge port forming member connected to a member forming the common liquid chamber 21 (hereinafter, also referred to as a common liquid chamber forming member). In the common liquid chamber forming member, an electric heat conversion element (hereinafter, also referred to as a heater) is arranged at a position facing each discharge port.

Next, each discharge port row group LG in the Cl chip 20 will be described in detail below.

<1. Yellow ink ejection port row group>
The Cl chip 20 in the present embodiment is provided with only one yellow ink ejection port row group (LG (Y)). The yellow ink ejection port row group LG (Y) is composed of two ejection port rows. The yellow ink ejection port row group LG (Y) may include three or more ejection port rows.

FIG. 5A is a diagram showing details of the yellow ink ejection port row group LG (Y). In the yellow ink ejection port row group LG (Y), the diameter of the ejection port is about 16 μm on both sides of the common liquid chamber 21, and the size of the ejected ink droplet is relatively 5 pl (picolitre). Two discharge port rows with a large discharge port 22 are provided. In each of these discharge port rows, 264 discharge ports 22 are arranged in the Y direction at intervals of 600 dpi (about 42.3 μm). Further, these discharge port rows are arranged so as to be spaced apart from each other by 1200 dpi (about 21.2 μm) in the Y direction.

Further, as described above, the heater 28 is provided at a position facing the discharge port 22. Further, the foam chamber 25 is provided so as to surround the heater 28, and the ink flow path 26 is provided so as to connect between the foam chamber 25 and the common liquid chamber 21. Further, a foreign matter blocking column 27 is provided to prevent foreign matter in the ink from entering the ink flow path 26. Since the configurations of the heater 28, the foam chamber 25, the ink flow path 26, and the foreign matter obstructing column 27 are the same in the other discharge port row groups, the description thereof will be omitted below.

<2. Black ink ejection port row group>
The Cl chip 20 in the present embodiment is provided with two ejection port rows of black ink (first ink) (LG (K1), LG (K2)). The black ink ejection port row groups LG (K1) and LG (K2) are each composed of two ejection port rows.

FIG. 5B is a diagram showing details of the black ink ejection port row group LG (K1). In the black ink ejection port row group LG (K1), the diameter of the ejection port on one side (left side of the figure) of the common liquid chamber 21 is about 16 μm, and the size of the ink droplets ejected is compared with about 5 pl. One discharge port row having a targetly large discharge port 22 is provided. Further, on the other side (right side of the figure) of the common liquid chamber 21, one discharge port having a discharge port diameter of about 12 μm and a medium discharge port 24 having a size of about 2 pl of ink droplets to be discharged. There are rows. In these discharge port rows, 264 discharge ports 22 and 24 are arranged in the Y direction at intervals of 600 dpi (about 42.3 μm), respectively. Further, these discharge port rows are arranged so as to be spaced apart from each other by 2400 dpi (about 10.6 μm) in the Y direction.

The black ink discharge port row group LG (K2) also has a discharge port row having a discharge port diameter of about 16 μm and a discharge port row having a discharge port diameter of about 12 μm, similarly to the discharge port row group LG (K1). have. However, the two discharge port row groups LG (K1) and LG (K2) are different in that the arrangement of the two discharge port rows arranged in each in the X direction is reversed. Further, the two discharge port rows having the same diameter in the discharge port rows LG (K1) and LG (K2) are positioned so as to be separated from each other by an interval of 1200 dpi (about 21.2 μm) in the Y direction. It is provided as follows.

<3. Cyan ink, magenta ink ejection port row group>
The Cl chip 20 in the present embodiment is provided with two cyan ink ejection port rows (LG (C1), LG (C2)). Each of these cyan ink ejection port rows LG (C1) and LG (C2) is composed of three ejection port rows.

As shown in FIG. 5C, in the cyan ink discharge port row group LG (C1), one discharge port row having a discharge port 22 is provided on one side (left side in the figure) of the common liquid chamber 21. Has been done. The ejection port 22 has a diameter of about 16 μm, and the size of the ejected ink droplet is relatively large, about 5 pl. On the other hand, two discharge port rows are provided on the other side (right side in the figure) of the common liquid chamber 21. One of the two discharge port rows has a discharge port diameter of about 12 μm and a medium discharge port 24 with an ejected ink droplet size of about 2 pl, and the other of the two discharge ports. It is provided at a position closer to the common liquid chamber 21 than the outlet row. One of the two discharge port rows has a discharge port 23 having a discharge port diameter of about 9 μm and a relatively small size of ink droplets to be discharged of about 1 pl, and a discharge port having a discharge port 24. It is provided at a position farther from the common liquid chamber 21 than the row.

In these discharge port rows, 264 discharge ports 22, 23, and 24 are arranged in the Y direction at intervals of 600 dpi (about 42.3 μm), respectively. Further, the discharge port row consisting of the discharge port 22 having a discharge port diameter of about 16 μm and the discharge port row consisting of the discharge port 24 having a discharge port diameter of about 12 μm are 2400 dpi (about 10.6 μm) in the Y direction. They are arranged at intervals. Further, the discharge port row consisting of the discharge port 24 having a discharge port diameter of about 12 μm and the discharge port row consisting of the discharge port 23 having a discharge port diameter of about 9 μm are 1200 dpi (about 21.2 μm) in the Y direction. They are arranged at intervals.

By ejecting cyan ink droplets of three different sizes of 5pl, 2pl, and 1pl in this way, it is possible to make the graininess inconspicuous in a wide range of density gradations.

Similar to the discharge port row group LG (C1), the cyan ink discharge port row group LG (C2) also has a discharge port row having a discharge port diameter of about 16 μm and a discharge port row having a discharge port diameter of about 12 μm. , It has a discharge port row having a discharge port diameter of about 9 μm. The two discharge port row groups LG (C1) and LG (C2) are different in that the arrangement of the three discharge port rows arranged in each in the X direction is reversed. Further, the two discharge port rows having the same diameter of the discharge port rows LG (C1) and LG (C2) are provided so as to be displaced by 1200 dpi (about 21.2 μm) in the Y direction. Has been done.

Further, the magenta ink ejection port row group LG (M1) is a cyan ink ejection port row group LG (C1), and the magenta ink ejection port row group LG (M2) is a cyan ink ejection port row group LG (C2). ) And each have the same configuration.

<4. Light blue ink discharge port row group>
The Cl chip 20 in the present embodiment is provided with one light blue ink ejection port row group (LG (LB)). The light blue ink ejection port row group LG (LB) is composed of four ejection port rows.

FIG. 5D is a diagram showing details of the light blue ink ejection port row group LG (LB).

As shown in FIG. 5D, in the light blue ink discharge port row group LG (LB), two discharge port rows are provided on one side (left side in the figure) of the common liquid chamber 21. One of the two discharge port rows has a discharge port diameter of about 12 μm and a medium discharge port 24 with an ejected ink droplet size of about 2 pl, and the other of the two discharge ports. It is provided at a position closer to the common liquid chamber 21 than the outlet row. The other discharge port row of the two has a discharge port 23 having a discharge port diameter of about 9 μm and a relatively small size of ink droplets to be discharged of about 1 pl, and has a discharge port 24. It is provided at a position farther from the common liquid chamber 21 than the outlet row. The same applies to the other side of the common liquid chamber 21 (on the right side in the figure), and two discharge port rows are provided, one is a discharge port row having a discharge port diameter of about 12 μm and the other is a discharge port row having a discharge port diameter of about 9 μm. Has been done. As described above, in the light blue ink discharge port row group, there are two discharge port rows having a discharge port diameter of about 12 μm and two discharge port rows having a discharge port diameter of about 9 μm, for a total of four discharge port rows. Is provided.

In these discharge port rows, 264 discharge ports 23 and 24 are arranged in the Y direction at intervals of 600 dpi (about 42.3 μm), respectively. Further, the two discharge port rows (the discharge port row having a discharge port diameter of about 16 μm and the discharge port row having a discharge port diameter of about 12 μm) located on the same side with respect to the common liquid chamber 21 are 1200 dpi in the Y direction. They are arranged at intervals of (about 10.6 μm).

<4. Arrangement order of discharge port rows in the chip>
As shown in FIG. 4, the Cl chip 20 in the present embodiment has a cyan ink ejection port row group LG (C1), a magenta ink ejection port row group LG (M1), and a light blue ink ejection port row group LG (C1) from the left side. They are arranged in the order of LG (LB). Subsequently, the black ink ejection port row group LG (K1), the yellow ink ejection port row group LG (Y), and the black ink ejection port row group LG (K2) are arranged in this order. Subsequently, each discharge port row group is arranged in the order of the magenta ink discharge port row group LG (M2) and the cyan ink discharge port row group LG (C2).

<Data generation processing>
FIG. 6 is a diagram illustrating an outline of a recorded data generation process used for recording executed by the CPU 201 according to the control program in the present embodiment. The control program used for the recorded data generation process is stored in the ROM 202 in advance. According to the control program stored in the ROM 202, the CPU 201 includes a color correction processing unit 601, an ink color separation processing unit 602, a γ correction processing unit 603, a quantization processing unit 604, an index expansion processing unit 605, and a distribution unit shown in FIG. It functions as a processing unit 606. Each unit shown in FIG. 6 is collectively referred to as a recorded data generation unit 600. That is, the CPU 201 functions as the recording data generation unit 600.

The image data input in this embodiment is an 8-bit RGB signal of each color having a resolution of 600 dpi and 256 gradations per pixel. This data is first sent to the color correction processing unit 601 and subjected to processing for associating a color space such as sRGB represented by the host PC 212 with a color space that can be represented by the recording device 100. Specifically, the color correction processing unit 601 can refer to a three-dimensional look-up table (LUT) stored in the ROM 202 in advance to convert an RGB 8-bit 256-value signal into an RGB 8-bit 256-value signal. Convert to a signal.

Next, the ink color separation processing unit 602 converts the data that has been color-corrected by the color correction processing unit 601 into data corresponding to the ink color used by the recording device 100. Specifically, the ink color separation processing unit 602 converts an RGB 8-bit 256-value signal into an 8-bit density signal for each ink color by referring to a three-dimensional LUT stored in the ROM 202 in advance.

The data decomposed into ink colors is input to the gamma correction processing unit 603, and the density value is corrected for each ink color. The gamma correction is a correction for making the density of the input data and the optical density of the image represented by the recording medium have a linear relationship. Specifically, the γ correction processing unit 603 refers to the one-dimensional LUT stored in the ROM 202 in advance, and converts the 8-bit 256-value density data of each ink color into 8-bit 256-value density data. .. In the present embodiment, as will be described later, the γ correction processing unit 603 converts the 8-bit 256-value density data of each ink color into 8-bit 256-value density data for each ejection port size. That is, the γ correction processing unit 603 acquires image data indicating the gradation value of each ink color and converts it into 8-bit 256-value density data for each size of the ejection port. For example, a process is performed in which the density data of the ink color of the black ink is converted into the density data used for the ejection port row having the ejection port 24 and the density data used for the ejection port row having the ejection port 22. Details will be described later.

After that, the density data of 8-bit 256 values corresponding to each ink color and each ejection port size is quantized by the quantization processing unit 604, and the 2-bit 4-value corresponding to each ink color and each ejection port size is performed. Quantization data is generated. In the present embodiment, the quantization processing method is not particularly limited, and a dither method, an error diffusion method, or the like can be adopted.

Next, the quantization data is sent to the index expansion processing unit 605, where it is converted into 1-bit binary data. For example, the number of ejected inks for a plurality of pixels having higher resolution (for example, two pixels of 2 pixels × 1 pixel for one pixel of the quantization data) according to the value of one pixel of the quantization data. An index pattern that defines the position is used. Then, according to the index pattern, binary data that defines the ejection or non-ejection of ink for each pixel having a higher resolution is generated. Details will be described later. The index pattern is stored in ROM 202 in advance.

After that, the binary data is sent to the distribution processing unit 606 of FIG. 6, and the binary data is distributed to a plurality of scans with respect to the unit area. Specifically, the distribution processing unit 606 uses a plurality of mask patterns that correspond to a plurality of scans and define the permissible or non-permissible ink ejection for each pixel, and the 1-bit binary value used in each of the plurality of scans. Generate the recorded data of. The 1-bit binary value recorded data is data indicating discharge or non-discharge of each discharge port. The plurality of mask patterns are stored in the ROM 202 in advance. Further, when recording is performed by the one-pass recording method, the processing in the distribution processing unit 606 is omitted.

Here, a mode is described in which the CPU 201 in the recording device 100 executes all the processes from the color correction processing unit 601 to the distribution processing unit 606. However, the CPU (not shown) in the PC 212 may execute some or all of the processing in the color correction processing unit 601 to the distribution processing unit 606. That is, the PC 212, which is an image processing device, may execute some or all of the processing of the recorded data generation unit 600.

<Index expansion process>
FIG. 7 is a diagram illustrating an index pattern. The details of the index expansion process performed by the index expansion processing unit 605 will be described with reference to FIGS. 7 (a) to 7 (g). In the present embodiment, one input pixel of the quantization data input from the quantization processing unit 604 is a pixel of 600 dpi and has 2 bits and 4 values (4 levels). FIG. 7 shows a case where the index expansion processing unit 605 indexes the 600 dpi input pixels into 2 × 1 recording pixels of 1200 dpi in the vertical direction and 600 dpi in the horizontal direction. The pixel values of "0", "1", and "2" shown in the pixel area of FIG. 7A are the number of times the ink is ejected with respect to the pixel area, respectively. When the input data is level 0, no dots are recorded in any of the 2 × 1 recording pixels, and when the input data is level 2, dots are recorded in any of the recording pixels. When the input data is level 0 or level 1, when a plurality of input pixels of the same level are adjacent to each other, as shown in FIG. 7A, recording pixels having a large number of ejections are alternately arranged in the vertical direction. NS.

When a plurality of pixels whose input data is level 1 are continuous as shown in FIG. 7 (b), if the index pattern is as shown in level 1 of FIG. 7 (a), the index pattern on the paper is shown in FIG. (C) is obtained, and the dot layout is as shown in FIG. 7 (d). That is, in the halftone region where the recording density (recording rate) is about 50%, the duplication between dots can be effectively avoided, so that the decrease in density due to the duplication of dots can be suppressed.

Further, when a plurality of level 3 pixels of the input data are continuous as shown in FIG. 7 (e), if the index pattern is as shown in level 3 of FIG. 7 (a), the index pattern on the paper is shown in FIG. 7. (F) is obtained, and the dot layout is as shown in FIG. 7 (g). That is, in the halftone region where the recording density (recording rate) is about 150%, the duplication between dots can be effectively avoided, so that the decrease in density due to the duplication of dots can be suppressed.

Here, the relationship between the recording rate and the number of shots, which will appear in the following description, will be described. The recording rate indicates the ratio of ink ejected from the ejection port to a predetermined pixel region having a predetermined resolution. In the present embodiment, the average number of dots formed per 600 dpi (the average number of times ink is ejected) is referred to as the number of shots. Further, when the average number of dots formed per 600 dpi is "2" (when the number of shots is two), that is, when ink is applied once to each recording pixel of 1200 dpi x 600 dpi, the recording rate is 100%. It shall be recorded. That is, in the case of FIG. 7A, recording is performed at a recording rate of 50% at level 1, a recording rate of 100% at level 2, and a recording rate of 150% at level 3.

FIG. 8 is a diagram when an index pattern different from that of FIG. 7 is used. The index pattern of FIG. 7 is preferable to the index pattern of FIG. 8, and an example of using the index pattern of FIG. 7 will be described in the present embodiment, but the reason why the index pattern of FIG. 8 is not preferable will be described below.

In the index pattern of FIG. 8A, the level 3 index pattern is different from the index pattern of FIG. 7A. As shown in FIG. 8A, the number of shots per 600 dpi can be increased from 3 shots to 4 shots by index-expanding the level 3 so that 2 dots are recorded in each recording pixel. It is possible. That is, in FIG. 7A, the recording rate of level 3 is 150%, whereas in FIG. 8A, the recording rate of level 3 is 200%.

However, assuming that the input quantization data is shown in FIG. 8 (b), the index pattern is as shown in level 3 in FIG. 8 (a). Therefore, the index pattern on the paper is shown in FIG. 8 (a). It becomes like c). The number of shots in the entire index pattern of FIG. 8 (c) is the same as that of FIG. 7 (f). As described above, although the number of shots in FIGS. 7 (f) and 8 (c) is the same, the layout of the dots in FIG. 8 (c) is as shown in FIG. 8 (d), and FIG. 7 (g). The concentration is lower than that of. This is because, in FIG. 8 (d), the region where the overlapping dots are formed is larger than that in FIG. 7 (g), so that the density is relatively low. In addition, if the number of shots is increased to 4, there is a concern that ink may overflow on the paper. Therefore, in the present embodiment, the index pattern shown in FIG. 7 is adopted, and the upper limit is set to be equivalent to 3 large dots to improve the density. The index pattern is not limited to the index pattern shown here, and the number of gradations may be increased by increasing the number of levels, for example.

<Large, medium and small dot decomposition>
Next, in the present embodiment, the details of the process of decomposing the density data so as to have the recording rate according to the size of the ejection port for each ink will be described. In the present embodiment, the dots discharged in the discharge port row of about 5 pl are referred to as large dots, the dots discharged in the discharge port row of about 2 pl are referred to as medium dots, and the dots discharged in the discharge port row of about 1 pl are referred to as small dots. Call. In the present embodiment, when the gamma correction is performed by the gamma correction processing unit 603, the density data is decomposed into large dots, medium dots, and small dots for each color. Specifically, the one-dimensional LUT satisfying the relationship shown in FIGS. 9 and 11 to 14 is referred to, and the density data of each dot is decomposed according to the input gradation value. That is, the γ correction processing unit 603 gamma-corrects the input gradation value (density data) of each ink using a one-dimensional LUT that satisfies the relationship shown in FIGS. 9 and 11 to 14, and makes each dot. Convert to the corresponding density data. After that, as described with reference to FIG. 6, the quantization process and the index expansion process are performed using the converted concentration data. That is, the relationship shown in FIGS. 9 and 11 to 14 is formed after the input gradation value (density data) is converted into the density data corresponding to each dot, and the quantization process and the index expansion process are performed. It shows the relationship with the number of dots. The decomposition of large dots, medium dots, and small dots is not limited to the execution by the gamma correction processing unit 603, and may be performed by, for example, the ink color separation processing unit 602.

<Disassembly of black that is easily affected by airflow>
FIG. 9 is a diagram showing the relationship between the average number of large dots and medium dots formed per 600 dpi with respect to the input gradation values of the black ink ejection port row groups LG (K1) and LG (K2) in the first recording mode. Is. The first recording mode is a recording mode that is easily affected by airflow, and in the present embodiment, it is a recording mode of a two-pass recording method. As described above, in the present embodiment, when the average number of dots formed per 600 dpi is 2, the recording rate is 100%. When the average number of dots formed per 600 dpi is one, the recording rate is 50%.

As shown in FIG. 9, as the input gradation value of black increases from 0 (first gradation value), the number of medium dots is first monotonically increased. This is because the graininess can be reduced by using relatively small dots in the low density gradation in which the graininess is conspicuous. Subsequently, the number of medium dots is increased until the gradation value 21 (second gradation value) is reached. After reaching the gradation value 21 (second gradation value), the number of medium dots is decreased, and at the same time, the number of large dots is increased. The middle dots may be reduced when the third gradation value, which is equal to or higher than the second gradation value, is exceeded. That is, when the gradation value 21 is exceeded, the middle dots may be reduced, or when a predetermined gradation value larger than the gradation value 21 is exceeded, the middle dots may be reduced. The reason for reducing the middle dots is to avoid the influence of airflow due to the ejection port rows of the middle dots of the black ink LG (K1) and LG (K2) being adjacent to the yellow ink ejection port row group LG (Y). Because.

As shown in FIG. 4, the yellow ink ejection port row group LG (Y) is composed of two large dot ejection port rows. The larger the size of the discharge port and the larger the number of discharge port rows, the stronger the generated airflow. Therefore, the discharge port rows of the middle dots of the black ink LG (K1) and LG (K2) are easily affected by the air flow of the yellow ink discharge port row group LG (Y). In general, the effect of airflow becomes more pronounced as the number of path decompositions decreases. This is because the number of inks ejected in one scan is larger than that in the case where the number of pass decompositions is large. In this embodiment, since the two-pass recording method is used, the gradation is decomposed so that the middle dots are not used in the gradation in which the landing deviation due to the influence of the air flow is easily visually recognized.

The number of large dots does not need to be increased at the same time as the number of medium dots decreases, and may be increased before the number of medium dots starts to decrease. That is, the gradation value in which the large dots increase may be the gradation value 21 or less (the second gradation value or less). This is because the gradation reversal does not occur before the number of middle dots decreases. After that, the number of medium dots becomes zero at the gradation value 56 (fifth gradation value), and a constant gradation is maintained at zero. Black is easily visible when the brightness is low and the landing deviation occurs. Therefore, in the present embodiment, the number of medium dots is set to zero and a constant gradation is maintained. However, the number of dots is not limited to zero, and may be reduced.

After that, when the gradation value 243 (fourth gradation value) is exceeded, the number of medium dots is increased again. This is done for the purpose of improving the maximum reproducible density at the maximum gradation value. The average number of large dots formed at the gradation value 243 (fourth gradation value) is 2 or more (recording rate is 100% or more). Both the number of medium dots and the number of large dots increase monotonically up to the maximum gradation value, and at the maximum gradation value, the number of large dots is 2.75 per 600 dpi and the number of medium dots is 0.625. However, as long as there is no contradiction in this embodiment, the number of shots is not limited to this. It will be described with reference to FIG. 10 that the improvement of the maximum reproducible density at the maximum gradation value is realized by increasing the number of medium dots again.

FIG. 10A is the quantized data of the black middle dots decomposed by using the LUT showing the relationship of FIG. 9 in the case of the maximum gradation value. When the input data of FIG. 10 (a) is developed according to the index pattern of FIG. 7 (a), the index pattern on the paper is as shown in FIG. 10 (b). In FIG. 10B, the average number of dots formed (number of shots) per 600 dpi of medium dots is 0.625 shots as in the maximum gradation value of FIG.

On the other hand, FIG. 10 (c) shows the quantized data of the large black dots decomposed by using the LUT showing the relationship of FIG. 9 in the case of the maximum gradation value. When the input data of FIG. 10 (c) is developed according to the index pattern of FIG. 7 (a), the index pattern on the paper is as shown in FIG. 10 (d). In FIG. 10D, the average number of dots formed (number of shots) per 600 dpi of medium dots is 2.75 shots as in the maximum gradation value of FIG.

In the present embodiment, as shown in FIG. 4, the discharge port row for ejecting large dots of black ink and the discharge port row for ejecting medium dots are displaced by 2400 dpi. Therefore, if the pixel position is shifted by 1200 dpi in the lateral direction by adjusting the ink ejection timing, the blank portion that cannot be filled with the large dots can be filled with the medium dots. This is illustrated in FIG. 10 (e). FIG. 10 (e) is a dot layout in which the index pattern of large dots (d) of FIG. 10 and the index pattern of medium dots shifted to 1200 dpi in the horizontal direction of FIG. 10 (b) are superimposed. In FIG. 10 (e), the ink consumption is the same as that in FIG. 7 (g) in which the number of large dots is 3 (the large dots 2.75 and the medium dots 0.625 are the same. (Equivalent to 3 large dots), but the reproducible density is higher in FIG. 10 (e). In other words, when medium dots are used, the same density can be reproduced with less ink consumption than when only large dots are used. The method of shifting the pixel position in the horizontal direction is not limited to this, and the pixel position may be shifted by any method.

Among the influence of airflow due to the large yellow dots, the black medium dots can be used because the gradation close to the maximum gradation value has a high density on the paper surface and unevenness due to the wobbling of the medium dots is difficult to see. This is because it is a key. As described above with reference to FIG. 8, if the amount of printing on the paper surface is simply increased, in the case of 2-pass recording, only large dots can be recorded up to 4 shots per 600 dpi. However, when only four large dots are recorded, the density with respect to the ink recording rate is lower than when the medium dots are used in combination, and there is a possibility that image harmful effects such as overflow due to excessive ink injection may occur.

Although FIG. 9 shows an example in which the number of medium dots of the maximum input gradation value 255 is larger than the number of medium dots of the gradation value 21, the maximum input gradation value and the medium dots of the gradation value 21 are shown. The relationship between the number of occurrences of is not limited to this.

In addition, the explanation so far has been made on the premise that there is an airflow effect due to the large yellow dots. Here, when the gradation value of yellow is small, the recording rate of yellow ink is also small, so that an air flow that shifts the landing position of the middle dot of black may not be generated. Therefore, it is conceivable to control different processes such as different black LUTs to be referred to according to the yellow gradation value. However, when the processing is changed according to the gradation value of yellow, the processing becomes complicated and may lead to an increase in cost. Therefore, in the present embodiment, it is possible that shading unevenness occurs by decomposing the large and medium dots of black as shown in FIG. 9 without depending on the input image data (yellow gradation value). It is suppressing.

<Decomposition of magenta and cyan, which are not easily affected by airflow>
FIG. 11 shows the relationship between the number of large dots, medium dots, and small dots formed per 600 dpi with respect to the input gradation values of the magenta ink ejection port rows LG (M1) and LG (M2) in the first recording mode. It is a figure which shows. As shown in FIG. 4, since the magenta ink ejection port row is separated from the yellow ejection port row, it is not easily affected by the air flow due to the yellow ink ejection. Therefore, unlike the case of the black ink shown in FIG. 9, it is not necessary to suppress the recording rate of medium dots and small dots that are easily displaced by the air flow. Hereinafter, a specific description will be given with reference to FIG.

As the input gradation value increases from the gradation value 0, the number of small dots is first monotonically increased. Subsequently, after reaching the gradation value 55 (eighth gradation value), the number of small dots is maintained, and at the same time, the number of medium dots is increased. The middle dots may be increased from the ninth gradation value equal to or higher than the eighth gradation value. After that, at the gradation value 116 (9th gradation value), the number of small dots is reduced, and the number of large dots is increased while maintaining the number of medium dots. The large dots may be increased from the tenth gradation value equal to or higher than the ninth gradation value. The upper limit number of small dots and medium dots is determined according to the unevenness of shading. At the gradation value 178, the number of small dots becomes zero, the number of medium dots starts to increase, and the number of large dots is maintained. The number of medium dots is maintained at the gradation value 183, and the large dots monotonically increase up to the maximum input gradation value.

The number of large, medium and small dots is not limited to the number of dots described above, and may be appropriately combined as long as gradation reversal does not occur.

As described above, unlike the black ink, the magenta ink does not have a gradation in which the number of dots decreases once and then increases again. This is because the magenta ink ejection port row group LG (M1) and LG (M2) are not adjacent to the yellow ink ejection port row group LG (Y), so that they are not easily affected by the air flow caused by the large yellow dots. be. When it is not easily affected by the air flow, it is not necessary to set the middle dots and small dots to zero in a predetermined halftone in consideration of the influence of the air flow as in black. When reproducing the same gradation, it is possible to increase the dot coverage area by using medium dots or small dots as compared with the case of using only large dots. Therefore, when it is not easily affected by the air flow, it is possible to obtain a preferable image quality with a small graininess by using medium dots or small dots.

Although FIG. 11 has been described as a diagram showing the relationship between magenta inks, large dots, medium dots, and small dots per 600 dpi with respect to the input gradation values of the cyan ink ejection port rows LG (C1) and LG (C2) have been described. The same applies to the relationship between the number of dots formed. This is because, as shown in FIG. 4, the cyan ink ejection port row is also separated from the yellow ejection port row, so that it is not easily affected by the air flow due to the yellow ink ejection.

<Decomposition of black that is not easily affected by airflow>
FIG. 12 shows large dots and medium dots per 600 dpi with respect to the input gradation values of the black ink ejection port rows LG (K1) and LG (K2) in the second recording mode different from the first recording mode. It is a figure which shows the relationship of the number of dots formation. The second recording mode is a recording mode in which the number of path decompositions is larger than that of the first recording mode. Therefore, the influence of the air flow is less than that of the first recording mode. Therefore, FIG. 12 shows a relationship different from that of FIG. Hereinafter, a specific description will be given.

In FIG. 12, as the input gradation value increases from the gradation value 0 (first gradation value), the number of medium dots is first monotonically increased. Subsequently, after reaching the gradation value 68 (sixth gradation value), the number of medium dots is maintained, and at the same time, the number of large dots is increased. After that, at the gradation value 241 (seventh gradation value), the number of medium dots is decreased, the large dots are continuously increased, and the maximum input gradation value is continued. As described above, in the second recording mode, unlike the example of FIG. 9, there is no relationship between the large dots and the medium dots in which the number of medium dots is decreased once and then increased again. This is because the effect of airflow is remarkable in the mode with a small number of passes, and in the mode with a large number of passes, the discharge port rows of the middle dots of the LG (K1) and LG (K2) of the black ink discharge the yellow ink. Even if it is adjacent to the exit row group LG (Y), the influence of airflow is small. Therefore, it is not necessary to reduce the number of dots. The number of dots of large, medium and small is not limited to the number of dots described above, and may be appropriately combined within a range in which gradation reversal does not occur.

In the example of FIG. 12, the number of medium dots is reduced in the high gradation region. In the high gradation region, almost all the regions on the paper surface are already covered with dots, so that the white portion of the paper is almost eliminated. Therefore, even if the number of medium dots is reduced, the graininess is less noticeable. However, it is not always necessary to reduce the number of medium dots, and it may be maintained or increased.

As described above, in the present embodiment, it is possible to perform recording in which the shading unevenness caused by the generation of the air flow accompanying the discharge from the other discharge port rows is reduced. Further, even in the discharge port row that is easily affected by the air flow, since the recording is performed by using the large dots and the small dots together at the maximum gradation value, the reproducible density can be improved.

<< Second Embodiment >>
In the first embodiment, an example has been described in which the airflow affecting the other ejection ports is the yellow ink ejection port row group LG (Y). Then, the first recording mode and the second recording are described in the form relating to the number of dots formed in the black ink ejection port row groups LG (K1) and LG (K2) adjacent to the yellow ink ejection port row group LG (Y). Each of the modes has been described. In addition, a form relating to the number of dots formed in the magenta ink ejection port row groups LG (M1) and LG (M2) that are not adjacent to the yellow ink ejection port row group LG (Y) has been described.

In the present embodiment, a mode considering a case where a discharge port row other than the yellow ink discharge port row group LG (Y) becomes a source of an air flow affecting other discharge ports will be described. Specifically, a mode in which the magenta ink ejection port row becomes a source of airflow that affects the adjacent cyan ink ejection port row will be described. The description of the same part as that of the first embodiment described above will be omitted.

In the present embodiment, the number of dots formed in the magenta ink ejection port row groups LG (M1) and LG (M2) adjacent to the cyan ink ejection port row groups LG (C1) and LG (C2) will be described. That is, the number of dots formed in the magenta ink ejection port row groups LG (M1) and LG (M2) on the side that causes the influence of the air flow will be described. In addition, the number of dots formed in the cyan ink ejection port row groups LG (C1) and LG (C2) on the side affected by the air flow will also be described.

<Disassembly of magenta that affects other outlet rows>
FIG. 13 shows the relationship between the number of large dots, medium dots, and small dots formed per 600 dpi with respect to the input gradation values of the magenta ink ejection port rows LG (M1) and LG (M2) in the first recording mode. It is a figure which shows. FIG. 13 is a diagram showing a relationship different from that of FIG. 11 in consideration of a case where the magenta ink ejection port row can be a source of an air flow that affects the cyan ink ejection port row. Hereinafter, a specific description will be given.

As the input gradation value increases from the gradation value 0, the number of small dots is first monotonically increased. Subsequently, after reaching the gradation value 55 (11th gradation value), the number of small dots is maintained, and at the same time, the number of medium dots is increased. The middle dots may be increased from the 14th gradation value equal to or higher than the 11th gradation value. After that, at the gradation value 116 (12th gradation value), the number of small dots is decreased, and the number of large dots is increased while maintaining the number of medium dots. After that, the number of large dots monotonously increases up to the maximum gradation value. Up to this point, it is the same as that of the first embodiment.

Subsequently, at the gradation value 171 (15th gradation value), the number of small dots becomes zero, and the number of medium dots starts to decrease. Unlike FIG. 11, the reason why the number of medium dots is reduced is to mitigate the influence of the airflow on the small dots and medium dots of cyan ink by the medium dots and large dots of magenta ink. By reducing the dots in the magenta, the total number of magenta ink shots is relatively reduced, so that the influence of the airflow on the cyan ink by the magenta ink can be reduced and the impact of the cyan ink can be alleviated. The strength of the generated airflow depends on the dot size and the number of shots. In FIG. 13, in the gradation value in which the middle dots are reduced, the number of large dots is slightly increased as compared with FIG. As described above, in FIG. 13, at the gradation value in which the number of medium dots is decreasing, the number of occurrences of medium dots decreases as the number of occurrences of large dots increases slightly, although the airflow derived from the large dots becomes slightly stronger. As a result, the influence of airflow derived from the middle dots is weakened. Therefore, when viewed comprehensively, the influence of the air flow is weaker when the LUT showing the relationship shown in FIG. 13 is adopted than when the LUT showing the relationship shown in FIG. 9 is adopted.

After that, the number of medium dots is maintained from the gradation value 181, and the number of medium dots starts to increase again at the gradation value 220 (16th gradation value) and increases to the maximum gradation value. The reason for increasing the number of medium dots is to improve the maximum reproducible density as described in the first embodiment. Further, when the magenta ink has a high gradation value up to the vicinity of the maximum gradation, the paper surface is almost filled with the dots of the magenta ink. Therefore, when the magenta ink is near the maximum gradation, even if the cyan ink is displaced and landed, the white area of the paper does not change (it is filled with magenta), so that the deviation of the cyan ink is not visible. .. Therefore, in the vicinity of the maximum gradation in which the unevenness of the cyan ink due to the flow of the magenta ink is difficult to see, it is possible to improve the maximum reproducible density of the magenta ink while preventing the deterioration of the image quality due to the unevenness of the shade of the cyan ink. Further, the same effect can be expected by increasing the number of dots not only for the medium dots but also for both the small dots and the medium dots from the gradation value 220, and further, the small dots from the gradation value 220 (13th gradation value). Only the number of dots may be increased.

<Decomposition of cyan affected by airflow>
FIG. 14 shows the relationship between the number of large dots, medium dots, and small dots formed per 600 dpi with respect to the input gradation values of the cyan ink ejection port rows LG (C1) and LG (C2) in the first recording mode. It is a figure which shows. FIG. 14 has a configuration in which the influence of the air flow of magenta ink is taken into consideration. Hereinafter, a specific description will be given.

As the input gradation value increases from 0, the number of small dots is first monotonically increased. Subsequently, after reaching the gradation value 41, the number of small dots is maintained, and at the same time, the number of medium dots is increased. After that, at the gradation value 82, the number of small dots is reduced, the number of medium dots is maintained, and the number of large dots is increased. The number of small dots and medium dots formed is smaller than that of FIG. 11 described in the first embodiment per 600 dpi in order to mitigate the influence of airflow. As a result, with respect to the cyan ink, since two dots are not arranged around 600 dpi for the small dots and the medium dots, the entire area is not filled, and the landing deviation due to the influence of the magenta airflow becomes difficult to visually recognize. After that, the number of large dots monotonously increases up to the maximum gradation value. In the first embodiment, the number of medium dots of the black ink, which is easily affected by the air flow, approaches zero at a predetermined gradation (see FIG. 9). This is because black ink has low brightness and unevenness is more easily visible than other colors. Since the brightness of the cyan ink is not as low as that of the black ink, as shown in FIG. 14, the number of medium dots and small dots is maintained as large as possible while avoiding the influence of the air flow.

Subsequently, the number of small dots becomes zero at the gradation value 125, the number of medium dots starts to decrease, and the number of medium dots becomes zero at the gradation value 166. Finally, at the gradation value 220, the number of medium dots starts to increase again and monotonically increases to the maximum gradation value. The reason for increasing the number of medium dots is to improve the maximum reproducible density as described in the first embodiment. Further, when the gradation value of the cyan ink is high up to the vicinity of the maximum gradation, the paper surface is almost filled with the dots of the cyan ink. Therefore, even if the cyan ink is displaced and landed, the white area of the paper does not change (it is filled with cyan), so that the displacement of the cyan ink is not visually recognized. Therefore, in the vicinity of the maximum gradation in which the unevenness of the cyan ink due to the flow of the magenta ink is difficult to see, it is possible to improve the maximum reproducible density of the cyan ink while preventing the deterioration of the image quality due to the unevenness of the shade of the cyan ink. Further, the same effect can be expected by increasing the number of dots not only for the medium dots but also for both the small dots and the medium dots from the gradation value 220, and further increasing the number of dots only for the small dots from the gradation value 220. May be good.

It should be noted that only the cyan ink has the relationship shown in FIG. 14 described in the present embodiment, and the magenta ink can be used in the same manner as the magenta ink (FIG. 11) in the first recording mode described in the first embodiment. The effect of is obtained. Similarly, only the magenta ink has the relationship shown in FIG. 13 described in the present embodiment, and the cyan ink may be used in the same manner as the cyan ink (FIG. 11) in the first recording mode described in the first embodiment. ..

The number of large, medium and small dots is not limited to the number of dots described above, and may be appropriately combined as long as gradation reversal does not occur. Further, the ink is not limited to magenta ink, and is not limited to ink as long as it has the same nozzle configuration. Further, the cyan ink discharge port row groups LG (C1) and LG (C2), and the magenta ink discharge port row groups LG (M1) and LG (M2) are configured as each discharge port row group without small dots. Is expected to have the same effect.

<Other Embodiments>
In each of the above-described embodiments, in addition to the cyan, magenta, yellow, and black ink ejection port rows, a blue ink ejection port row group is provided in order to reduce the color shift in the blue hue that can be reproduced by cyan and magenta. Was described. However, implementation in other forms is also possible. For example, in order to reduce the color shift in the red hue that can be reproduced by magenta and yellow, even if the red ink ejection port row group is provided, the configuration is the same as that of the blue ink ejection port row group in the above-described embodiment. Can be taken. In the case of having a group of green ink ejection ports to reduce the color shift in the green hue that can be reproduced by yellow and cyan, or in the case of gray ink in order to reduce the color shift in the gray hue due to the variation in the ejection amount. The same applies to.

In each of the above-described embodiments, the mode in which the reciprocating scanning of the recording head and the transport of the recording medium are alternately performed to record over the entire area on the recording medium has been described, but other embodiments are also possible. .. For example, the recording head may be scanned in only one direction for recording. Further, a so-called full-line type recording device that uses a long recording head extending over the entire width direction of the recording medium and ejects ink while transporting the recording medium to the recording head for recording. Even if there is, the configuration described in each embodiment can be adopted.

Further, in each of the above-described embodiments, a mode in which a discharge port row having a large discharge port diameter is composed of a discharge port having a diameter of about 16 μm has been described. A form in which a discharge port row having a medium discharge port diameter is composed of a discharge port having a diameter of about 12 μm has been described. A form in which a discharge port row having a small discharge port diameter is composed of a discharge port having a diameter of about 9 μm has been described. However, the present invention is not limited to these examples, and the same configuration as in each embodiment can be adopted as long as the magnitude relationship of the discharge port is roughly divided into three stages. For example, the first discharge port row may be composed of an elliptical discharge port having a major axis of about 8 μm and a minor axis of about 7 μm. The second discharge port row may be composed of an elliptical discharge port having a major axis of about 6 μm and a minor axis of about 5 μm. The third discharge port row may be composed of an elliptical discharge port having a major axis of about 4 μm and a minor axis of about 3 μm. Even in such a form, the first discharge port row is a discharge port row having a large discharge port diameter, the second discharge port row is a discharge port row having a medium discharge port diameter, and the third discharge port row is a discharge port diameter. The same effect as that of the above-described embodiment can be obtained by treating the discharge port row as having a small size.

Further, in each of the embodiments described above, it is a premise that each discharge port row is arranged as shown in FIG. When the arrangement of each discharge port row is different from the form shown in FIG. 4, the above-described embodiment can be appropriately modified and applied according to the arrangement of the discharge port rows.

The present invention supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and one or more processors in the computer of the system or device reads and executes the program. It can also be realized by the processing to be performed. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

200 Main control unit 201 CPU
603 γ correction processing unit 605 Index expansion processing unit

Claims (19)

A first discharge port row including a first discharge port row in which discharge ports having a first diameter are arranged and a second discharge port row in which discharge ports having a second diameter larger than the first diameter are arranged are included. A first ejection port row group for ejecting ink, and
A second ejection port row group adjacent to the first ejection port row group and for ejecting ink different from the ink ejected by the first ejection port row group.
An image processing device used in a recording device provided with a recording head having at least one of the above, which generates recording data indicating discharge or non-discharge of each discharge port.
An acquisition means for acquiring image data indicating a gradation value, and
Based on the acquired image data, in the first ejection port row, a recording rate indicating the ratio of ink ejected to a predetermined pixel region having a predetermined resolution is determined.
As the gradation value increases, it increases from the first gradation value to the second gradation value larger than the first gradation value.
When the third gradation value, which is equal to or higher than the second gradation value, is exceeded, the value decreases.
A generation means for generating the recorded data so as to increase when the fourth gradation value larger than the third gradation value is exceeded.
An image processing device comprising. In the generation means, the recording rate of the first discharge port row is a fifth gradation value between the third gradation value and the fourth gradation value, and the fourth gradation. The image processing apparatus according to claim 1, wherein the recorded data is generated so as to be constant with respect to the value. The generation means is characterized in that the recording data is generated so that the recording rate of the first discharge port row becomes zero between the fifth gradation value and the fourth gradation value. The image processing apparatus according to claim 2. The generation means generates the recorded data so that the recording rate of the first discharge port row at the maximum gradation value becomes larger than the recording rate of the first discharge port row at the second gradation value. The image processing apparatus according to any one of claims 1 to 3, wherein the image processing apparatus is generated. Claims 1 to 4 are characterized in that the generation means generates the recorded data so that the gradation value at which the discharge of the second discharge port row is started is equal to or less than the second gradation value. The image processing apparatus according to any one of the above. Any of claims 1 to 5, wherein the generation means generates the recorded data so that the recording rate of the second discharge port row at the fourth gradation value is 100% or more. The image processing apparatus according to one item. The recording device is
It is possible to switch between the first recording mode and the second recording mode in which the number of scans to the unit area is larger than that of the first recording mode.
The generation means
In the first recording mode, the recording rate of the first ink in the first ejection port row is
As the gradation value increases, the gradation value increases from the first gradation value to the second gradation value.
It decreases when the third gradation value is exceeded,
The recorded data is generated so as to increase when the fourth gradation value is exceeded.
In the second recording mode, the recording rate of the first ink in the first ejection port row is
As the gradation value increases, the recorded data is recorded so that the first gradation value increases to a sixth gradation value larger than the second gradation value and does not become zero up to the maximum gradation value. The image processing apparatus according to any one of claims 1 to 6, wherein the image processing apparatus is generated. In the generation means, the recording rate of the first ink in the first ejection port row in the second recording mode is a seventh between the sixth gradation value and the maximum gradation value. The image processing apparatus according to claim 7, wherein the recorded data is generated so as to decrease when the gradation value is exceeded. The recording head
The image processing apparatus according to any one of claims 1 to 8, wherein the second discharge port row group includes two or more of the second discharge port rows. The recording head
The first discharge port includes a third discharge port row in which a third discharge port smaller than the first diameter is arranged, the first discharge port row, and the second discharge port row. Further having a third ejection port row group for ejecting ink different from the ink ejected in the row group and the second ejection port row group.
The image processing apparatus according to claim 9, wherein the third discharge port row group and the second discharge port row group are arranged so as not to be adjacent to each other. The generation means
The recording rate of the third discharge port row in the third discharge port row group is
As the gradation value increases, the first gradation value increases to an eighth gradation value larger than the first gradation value.
When the ninth gradation value, which is equal to or higher than the eighth gradation value, is exceeded, the value decreases.
The recording rate of the first discharge port row in the third discharge port row group is
As the gradation value increases, it increases from the ninth gradation value equal to or higher than the eighth gradation value, and does not decrease thereafter.
The recording rate of the second discharge port row in the third discharge port row group is
The tenth aspect of claim 10, wherein the recorded data is generated so that the tenth gradation value larger than the ninth gradation value increases with the increase of the gradation value and does not decrease thereafter. Image processing device. The generation means
The recording rate of the third discharge port row in the third discharge port row group is
As the gradation value increases, the first gradation value increases to the eleventh gradation value larger than the first gradation value.
It decreases when the 12th gradation value, which is equal to or higher than the 11th gradation value, is exceeded.
The image processing apparatus according to claim 10, wherein the recorded data is generated so as to increase when the thirteenth gradation value, which is equal to or higher than the twelfth gradation value, is exceeded. The generation means
The recording rate of the first discharge port row in the third discharge port row group is
As the gradation value increases, it increases from the 14th gradation value which is larger than the first gradation value and is equal to or higher than the 11th gradation value.
It decreases when the 15th gradation value, which is equal to or higher than the 14th gradation value, is exceeded.
The image processing apparatus according to claim 10, wherein the recorded data is generated so as to increase when the 16th gradation value, which is equal to or higher than the 15th gradation value, is exceeded. Claims 1 to 13 are characterized in that the first ink ejected by the first ejection port row group is an ink having a lower brightness than other inks ejected by the other ejection port row group. The image processing apparatus according to any one of the above. The acquisition means acquires data indicating gradation values decomposed into each ink color as the image data, and obtains the data.
The generation means
The gradation value decomposed into each ink color is converted into the gradation value used for recording in each of the ejection port rows according to the recording rate.
Quantization processing is performed based on the converted gradation value,
The image processing apparatus according to any one of claims 1 to 14, wherein the recorded data is generated through an index expansion process based on the quantized data. A first discharge port row including a first discharge port row in which discharge ports having a first diameter are arranged and a second discharge port row in which discharge ports having a second diameter larger than the first diameter are arranged are included. A first ejection port row group for ejecting ink, and
A second ejection port row group adjacent to the first ejection port row group and for ejecting ink different from the ink ejected by the first ejection port row group.
A recording device having a recording head having at least
In the first ejection port row, the recording rate indicating the ratio of the ink ejected to the predetermined pixel region of the predetermined resolution is
As the gradation value increases, it increases from the first gradation value to the second gradation value larger than the first gradation value.
When the third gradation value, which is equal to or higher than the second gradation value, is exceeded, the value decreases.
A recording device characterized in that it increases when a fourth gradation value larger than the third gradation value is exceeded. The recording head
The recording device according to claim 16, wherein the second discharge port row group includes two or more of the second discharge port rows. A first discharge port row including a first discharge port row in which discharge ports having a first diameter are arranged and a second discharge port row in which discharge ports having a second diameter larger than the first diameter are arranged are included. A first ejection port row group for ejecting ink, and
A second ejection port row group adjacent to the first ejection port row group and for ejecting ink different from the ink ejected by the first ejection port row group.
A recording data generation method for generating recording data indicating discharge or non-discharge of each discharge port, which is used in a recording device provided with a recording head having at least.
An acquisition step for acquiring image data indicating a gradation value, and
Based on the acquired image data, in the first ejection port row, a recording rate indicating the ratio of ink ejected to a predetermined pixel region having a predetermined resolution is determined.
As the gradation value increases, it increases from the first gradation value to the second gradation value larger than the first gradation value.
When the third gradation value, which is equal to or higher than the second gradation value, is exceeded, the value decreases.
A method for generating recorded data, which comprises a step of generating the recorded data so that the value increases when the fourth gradation value larger than the third gradation value is exceeded. A program for causing a computer to function as each means of the image processing apparatus according to any one of claims 1 to 15.

Images