JP2007008176A - Printer, printer control program, printer control method, apparatus for generating printing data, program for generating printing data, and method for generating printing data - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a novel printer that can solve or make almost inconspicious the banding phenomenon due to the flight deflection phenomenon, and to provide a printer control program, a printer control method, an apparatus for generating printing data, a program for generating printing data, and a method for generating printing data. <P>SOLUTION: The printer 100 comprises: a first image data acquiring part 10 that acquires the first image data; a nozzle information setting section 11 that generates a nozzle setting information table in which whether nozzles are used or not is set for each pixel data of the acquired first image data based on nozzle information showing the profile of each nozzle N; a nozzle setting information table storage section 13 that memorizes the nozzle setting information table; and the second image data generating section 14 that alters the pixel value of the pixel data set as nozzle nonuse in the first image data into the minimum density value and generates the second image data formed by distributing the pixel value before the alteration to the circumference pixel. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a printing apparatus, a printing apparatus control program, and a printing apparatus control method used for a facsimile apparatus, a copying machine, a printing apparatus for office automation equipment, and the like. ) A so-called ink jet printing apparatus, a printing apparatus control program and a printing apparatus control method, and a printing data generation apparatus, printing data generation program and printing, which are ejected onto the apparatus so as to draw predetermined characters and images. The present invention relates to a data generation method.

The following describes a printing apparatus, particularly a printer that employs an inkjet method (hereinafter referred to as an “inkjet printer”).
Ink jet printers are generally inexpensive and can easily obtain high-quality color prints, and are widely used not only in offices but also in general users with the spread of personal computers and digital cameras.

  In such an ink jet printer, a moving body called a carriage or the like in which an ink cartridge and a print head are integrally provided generally moves on a medium (for example, printing paper) used for printing in the paper feeding direction. By ejecting (injecting) liquid ink particles in the form of dots from the nozzles of the print head while reciprocating in a direction perpendicular to the direction, a predetermined character or image is drawn on the medium to create a desired printed matter. It is like that. The carriage is equipped with ink cartridges of four colors (black, yellow, magenta, cyan) including black (black) and a print head for each color, so that not only monochrome printing but also full-color printing combining each color is possible. (Furthermore, 6 colors, 7 colors, or 8 colors in which light cyan, light magenta, etc. are added to these colors are also put into practical use).

  In addition, in this type of ink jet printer in which printing is executed while the print head on the carriage is reciprocated in a direction perpendicular to the paper feed direction, several tens of print heads are used to cleanly print the entire page. Since it is necessary to reciprocate more than 100 times from the first time, there is a disadvantage that it takes much longer printing time than other types of printing apparatuses, for example, laser printers using electrophotographic technology such as copying machines. is there.

  On the other hand, in an inkjet printer of a type in which a long print head having the same (or long) dimension as the width of the print paper is used and a carriage is not used, it is not necessary to move the print head in the width direction of the print paper. Since printing can be performed by so-called one scanning (one pass), high-speed printing is possible as in the case of the laser printer. In addition, since a carriage for mounting the print head and a drive system for moving the print head are not required, the printer casing can be reduced in size and weight, and the quietness can be greatly improved. Yes. The former inkjet printer is generally called a “multi-pass printer”, and the latter inkjet printer is generally called a “line head printer” or a “serial printer”.

  By the way, a print head indispensable for such an ink jet printer is one in which fine nozzles having a diameter of about 10 to 70 μm are arranged in one row at a constant interval or in a plurality of rows in the printing direction. Due to manufacturing error, the ink ejection direction of some nozzles may be tilted, or the position of the nozzles may be shifted from the ideal position. A so-called “flight bend phenomenon” may occur, such as deviation. In addition, there are inks whose ink amount is greatly increased or decreased as compared with the ideal amount, as the variation is large due to the dispersion characteristics of the nozzles.

  As a result, a printing defect referred to as a so-called “banding phenomenon” may occur in a portion printed using the defective nozzle, and the print quality may be significantly reduced. In other words, when the “flight bend” phenomenon occurs, the distance between the dots ejected by the adjacent nozzles becomes non-uniform, and the portion where the distance between adjacent dots is longer than normal is indicated by “white streaks (if the printing paper is white) ) ”Occurs, and“ dark streaks ”occur in a portion where the distance between adjacent dots is shorter than normal. Even when the ink amount is not ideal, a dark streak occurs in a nozzle portion where the ink amount is large, and a white streak occurs in a portion where the ink amount decreases.

  In particular, such banding phenomenon is caused by the “line head type printer” in which the print head or the medium used for printing is fixed (one pass printing), as compared to the case of the “multi-pass type printer” (serial printer) as described above. (In multi-pass printers, there is a technique that makes banding inconspicuous by using the print head reciprocating many times).

Therefore, in order to prevent a kind of printing failure due to such "banding phenomenon", research and development in the so-called hardware part such as improvement of print head manufacturing technology and design improvement has been earnestly advanced. It is difficult to provide a print head in which 100% “banding phenomenon” does not occur due to manufacturing costs, technical aspects, and the like.
Therefore, in addition to the improvement in the hardware part as described above, a technology that reduces such “banding phenomenon” by using a so-called software method such as printing control as described below is used in combination. Has been.

  For example, in Patent Document 1 and Patent Document 2 shown below, in order to deal with nozzle variations and ink non-ejection, shading correction technology is used to deal with head variations using a shading correction technique in areas where the density is low. For dark portions, other colors are used (for example, when printing in black, cyan or magenta is used) so that banding and variations are not noticeable.

Further, in Patent Document 3 shown below, a solid image (that is, a relatively large area of an image portion with respect to a line image and a region that is densely covered with ink, is completely covered by an edge effect or the like. In some cases, the method of increasing the discharge amount of the adjacent nozzles in the vicinity of the non-discharge nozzles and generating a solid image with the entire nozzles is adopted.
In Patent Document 4 shown below, the variation amount of each nozzle is fed back to error diffusion and processed to absorb the variation in the ejection amount of the ink ejected from the nozzle, thereby avoiding the banding phenomenon.

Further, in Patent Document 5 shown below, when there is a nozzle (N) in which an abnormality has occurred in the ink ejection state, print data corresponding to the abnormal nozzle (N) is recorded in the vicinity of the abnormal nozzle (N). By adding to the recording data corresponding to the neighboring nozzles (N−1) and (N + 1) located at, the recording data corresponding to the abnormal nozzle (N) is compensated, and the banding phenomenon is avoided.
Japanese Patent Laid-Open No. 2002-19101 JP 2003-136702 A JP 2003-63043 A JP-A-5-30361 JP 2004-58284 A

However, in the technique of reducing the banding phenomenon and variation using other colors as in the prior arts of Patent Document 1 and Patent Document 2 described above, the hue of the processed portion changes, so color photographs are taken. Not suitable for printing that requires high image quality and high quality, such as image printing.
In addition, the method of avoiding the “white streak phenomenon” by distributing the information on the non-ejection nozzles to the left and right for areas with high density is reduced when this is applied to the “flight bend phenomenon” described above. Although it is possible, there is a problem that banding still remains in a portion where the concentration is high.

  In the method such as the prior art of Patent Document 3 described above, there is no problem if the printed matter is a solid image, but this method cannot be used if the printed matter is a halftone printed matter. In addition, the method of filling thin lines with other colors is fine as long as it is used very little, but in an image in which other colors occur continuously, a part of the image is similar to the former. The problem remains that the hue changes.

Further, in the method such as the conventional technique of Patent Document 4 described above, there is a problem that the process of performing appropriate feedback is complicated and difficult to solve for the problem that the dot formation content is shifted.
Further, in the method such as the prior art of Patent Document 5 described above, when dots having different sizes are formed by the peripheral nozzles in post-processing after binarization, if the dots have γ characteristics, that portion There is a problem in that there is a risk of the area gradation of the image being destroyed.

  Therefore, the present invention has been made paying attention to such an unsolved problem of the conventional technology, and is a novel printing apparatus and printing apparatus capable of eliminating or hardly conspicuously deteriorating the printing image quality. A first object is to provide a control program, a printing apparatus control method, a printing data generation apparatus, a printing data generation program, and a printing data generation method.

Also, a novel printing apparatus, printing apparatus control program, printing apparatus control method, printing data generation apparatus, and printing data that can eliminate or hardly obscure the printing image quality due to the banding phenomenon caused by the flight bending phenomenon It is a second object to provide a generation program and a print data generation method.
Also, a novel printing apparatus, printing apparatus control program and printing apparatus control method capable of eliminating or hardly conspicuously deteriorating print image quality due to ink ejection failure, printing data generation apparatus, printing data generation program and printing A third object is to provide a data generation method.

[Mode 1] In order to achieve the first to third objects, a printing apparatus according to mode 1 includes:
A printing apparatus configured to print an image on the medium by a print head having a nozzle capable of forming two or more types of dots having different sizes on a medium used for printing,
First image data acquisition means for acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Nozzle information storage means for storing nozzle information indicating the characteristics of the nozzle;
Nozzle use information setting means for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data of the first image data based on the nozzle information;
In the first image data, the pixel value of the pixel data set as non-use by the nozzle use information setting unit is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. Second image data generating means for generating second image data distributed to the pixel values of the unprocessed pixels,
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of the pixel data in the second image data into an N (M> N ≧ 2) value. N-value conversion processing means for
Print data generation means for generating print data defining information relating to dot formation contents of the nozzle corresponding to the third image data;
Printing means for printing the image on the medium by the print head based on the printing data.

  With such a configuration, it is possible to acquire the first image data including a plurality of pixel data respectively corresponding to pixel values of M (M ≧ 3) values by the image data acquisition means, and the nozzle Nozzle information indicating the characteristics of the nozzle can be stored by the information storage means, and each pixel data for each pixel data of the first image data can be stored by the nozzle use information setting means based on the nozzle information. It is possible to set whether or not to use the nozzle corresponding to the pixel value of the pixel data set as not used by the nozzle use information setting unit in the first image data by the second image data generation unit Is changed to the minimum density value, and the original pixel value before the change is distributed to pixel values of unprocessed pixels located in the vicinity of the pixel value. In the process of converting the pixel value of the M (M ≧ 3) value of the pixel data in the second image data into the N (M> N ≧ 2) value by the N-value conversion processing unit. It is possible to generate third image data by performing a certain N-ary process, and for printing that defines information relating to the dot formation contents of the nozzle corresponding to the third image data by the print data generation means Data can be generated, and the image can be printed on the print medium by the print head based on the print data by printing means.

  Therefore, based on the nozzle information, for example, the “banding phenomenon” caused by the nozzle characteristics caused by, for example, defective ink ejection at the nozzle or the “flight bending phenomenon” of the nozzle in which the dot formation position deviates from the ideal position. With respect to the pixel data, the nozzle corresponding to the pixel data can be set to be unused for a part or all of the pixel data, and the pixel value of the pixel data can be set to the lowest density value. Pixel values can be distributed to surrounding pixel data, so that after N-value processing using an error diffusion method, pixel data of a portion that has been set to non-use depends on the N-value processing method. The pixel value corresponding to the loss of the pixel data of the portion that is set as non-use is formed as a relatively small dot or no dot is formed. Because it is compensated by the raw data, there is an advantage that it is possible to reduce deterioration of the printed image quality such as "white stripes" or "dark stripes" while maintaining the original area tone.

  Here, the dot refers to one region formed by ink ejected from one or a plurality of nozzles landing on a print medium. Further, “dots” are not “zero” in area, and of course have a certain size (area), and there are a plurality of types for each size. However, dots formed by ejecting ink are not always perfect circles. For example, when dots are formed in a shape other than a perfect circle such as an ellipse, the average diameter is treated as the dot diameter, or the area equal to the area of the dots formed by ejecting a certain amount of ink is used. In some cases, a perfect circle equivalent dot is assumed and the diameter of the equivalent dot is treated as the dot diameter. In addition, for example, a method for hitting dots having different densities includes a method of hitting dots having the same dot size and different densities, a method of hitting dots having the same density and different sizes, and ejection of ink having the same density. It is possible to consider a method in which the amount of dots is different and the density is varied by overstrike. In addition, when one ink droplet ejected from one nozzle is separated and landed, it is considered as one dot, but two nozzles or two or more formed from one nozzle around the time. If two dots are stuck, it is assumed that two dots are formed. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

  The first image data acquisition unit acquires image data input from an optical print result reading unit such as a scanner unit, or image data stored in an external device via a network such as a LAN or WAN. Can be acquired passively or actively, or image data can be acquired from a recording medium such as a CD-ROM or DVD-ROM via a drive device such as a CD drive or DVD drive of the printing apparatus, or the printing apparatus can Acquire image data stored in a storage device. That is, the acquisition includes at least input, acquisition, reception, and reading. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

  The nozzle information storage means stores nozzle information at any time and at any time, and may store nozzle amount information in advance or without storing nozzle information in advance. The nozzle information may be stored by an external input or the like during operation of the printing apparatus. For example, before this printing apparatus is sold as a product at the time of factory shipment, the dot formation positions of the nozzles constituting the print head from the print result by the print head using optical print result reading means such as scanner means The nozzle information such as the amount of misalignment and the ink discharge state is inspected, and the inspection results are stored in advance. Any timing may be used as long as it can be stored at the time of use of the product, such as inspecting the amount and ink discharge state and storing the inspection result. In addition, in order to cope with a change in the characteristics of the print head after use of the printing apparatus, printing by the print head using an optical print result reading means such as a scanner means periodically or at a predetermined time is used. The nozzle information is updated by inspecting the print head dot formation position deviation and ink ejection status from the results and storing the inspection results together with the data at the time of shipment from the factory or overwriting the data. You may be able to do it. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

Also, the above-mentioned ink ejection failure means that ink cannot be ejected as ideal, such as ink cannot be ejected, the amount of ink ejected is insufficient, the amount of ink ejected is too large, and ink cannot be ejected to the ideal position. That is.
The minimum density value is a value at which the density is lowest in the range of the gradation value of the image. For example, when the gradation of the image is expressed by 8 bits (0 to 255), the pixel value is luminance. For example, the value is “255”, and the density value is “0”.

  Further, the information regarding the dot formation contents of the nozzle includes information regarding the presence / absence of dots (forming / not forming dots by the nozzle) for each pixel value of the image data, and the dot size (for example, large) -It is composed of information necessary for forming dots by nozzles such as information on one of three types (medium and small). For example, when there is only one type of formation size, it is related to the presence or absence of dots. You may comprise only information.

  In addition, as described above, the “banding phenomenon” is caused by a so-called “flight bending phenomenon” caused by a nozzle whose dot formation position is deviated from an ideal formation position. There are printing defects in which “white streaks” and “dark streaks” occur in the printing result due to printing defects in which “streaks” occur simultaneously and ink ejection defects such as non-ejection of nozzle ink. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

  In addition, this “white streak” is, for example, a phenomenon in which the distance between adjacent dots is continuously larger than a predetermined distance due to the “flight curve phenomenon”, and the color of the background of the print medium is conspicuous in a streak shape. In addition, “dark streaks” are the same as the “flying curve phenomenon,” where the phenomenon in which the distance between adjacent dots becomes shorter than a predetermined distance occurs continuously. The color of the dot disappears, or the distance between the dots becomes shorter, which makes it appear darker, or some of the dots that are off are overlapped with normal dots and the overlapped part becomes dark streaks It shall be the part (area) that stands out. In addition, white streaks may occur due to nozzles with a small amount of ink, while dark streaks may occur due to nozzles with a large amount of ink. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

  The error diffusion method is the same as a known error diffusion method which is one method of N-value processing. For example, the pixel value of the M-value image data with a threshold value “128” as a boundary. When the binarization process is performed to convert the value to “0” if the value is smaller than “128” and to “255” if the value is “128” or more, if the pixel value of the selected pixel is “101”, “101” is “0”. The difference between “0” after conversion and “101” before conversion is regarded as an error, and binarization around the selected pixel is performed on an unprocessed pixel according to a predetermined diffusion method. Spread.

[Mode 2] Further, the printing apparatus of mode 2 is the printing apparatus of mode 1,
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
The nozzle use information setting means sets the nozzle to non-use for all the pixel data corresponding to the nozzle having the ink ejection failure.
With such a configuration, it is possible to easily identify nozzles having ink ejection defects such as ink that cannot be ejected, insufficient ink ejection amount, and excessive ink ejection amount. Since all the pixel data corresponding to the nozzle can be set so that the nozzle is not used, for example, the pixel value of the pixel data corresponding to the nozzle that cannot eject ink is determined by the surrounding pixels. “White streaks” and “Dense streaks” due to “banding phenomenon” that causes “ink ejection failure” while maintaining the original area gradation, etc. The effect that the deterioration of the print image quality can be reduced.

  Here, since the presence or absence of ink ejection failure at the nozzle can be detected by, for example, a CCD sensor provided in the printing apparatus, information indicating the presence or absence of ink ejection failure is generated based on the detection result. Can do. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

[Mode 3] Furthermore, the printing apparatus of mode 3 is the printing apparatus of mode 1 or 2,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
With such a configuration, it is possible to easily identify the nozzle that causes the so-called “flying curve phenomenon” that occurs when the dot forming position deviates from the ideal forming position, and the flying curve amount is large. Therefore, for pixel data corresponding to such nozzles, whether or not to use the nozzle can be set appropriately, and the number of pixel data to be set as non-use can be determined by the amount of flight curve Since it can be made variable according to the size of the nozzle, the “flying phenomenon” can be changed by setting the proper use / nonuse of the nozzle to avoid the “banding phenomenon” caused by the “flying phenomenon”. It is possible to appropriately reduce the deterioration of the print image quality such as “white streaks” and “dark streaks” due to the “banding phenomenon” as a cause of occurrence.

[Form 4] Furthermore, the printing apparatus of form 4 is the printing apparatus of form 3,
The nozzle use information setting unit is characterized in that the nozzle is set not to be used for a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount.
With such a configuration, it is possible to set the nozzle to non-use with respect to pixel data corresponding to a nozzle having a flight curve amount larger than a predetermined amount, and set the density of the pixel data set as non-use to the surrounding pixels. Therefore, the print quality deterioration such as “white streaks” and “dark streaks” due to the “banding phenomenon” that causes the “flying curve phenomenon” can be appropriately reduced.

  Here, the method of specifying the “part of the pixel data corresponding to the nozzle whose positional deviation amount is larger than the predetermined amount” is, for example, that the nozzle whose positional deviation amount is larger than the predetermined amount is not used according to the print resolution. There is a method of determining a probability of setting and determining a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount based on the probability. For example, when the printing resolution is low, the probability of setting a nozzle having a positional deviation amount larger than a predetermined amount as non-use is reduced (for example, 10%), and when the printing resolution is high, the nozzle having a positional deviation amount larger than a predetermined amount. Increase the probability of setting as non-use (for example, 30%). Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

[Mode 5] Further, the printing apparatus of mode 5 is the printing apparatus of any one of modes 1 to 4,
In the process of distributing the original pixel value, the second image data generation unit is configured to randomly convert the original pixel value before the change to a pixel value of a pixel image located in the vicinity of the pixel image of the pixel value. It is characterized by distribution.
With such a configuration, when distributing the original pixel values, the pixel values can be distributed at a random distribution ratio, so that banding is less noticeable than regular distribution at the same distribution ratio. Thus, the effect of improving the image quality of the printed result can be obtained.

  Here, the “random ratio” can be obtained, for example, by generating a random number using a random number generator, a random number generation program, or the like and calculating a distribution ratio using the generated random number. For example, a ratio calculation table in which a numerical value range of a random number is divided into a plurality of numbers, and different calculation methods (for example, error diffusion matrices having different diffusion ratios) for each divided numerical value range are registered in advance. There is a method of preparing, selecting a ratio calculation method corresponding to the generated random number from the table, and calculating a distribution ratio using the selected method. In this way, by determining the ratio at random, when performing the same image processing, different distribution results are obtained each time the processing is performed (however, if the same random value is generated continuously, the same result is obtained) Is). On the contrary, in the case of non-random, when the same image processing is performed, the same distribution result is obtained every time the processing is performed. Hereinafter, a form relating to “printing apparatus control program”, a form relating to “printing apparatus control method”, a form relating to “printing data generation apparatus”, a form relating to “printing data generation program”, a form relating to “printing data generation method”, In addition, the same applies to the description relating to the “recording medium on which the program is recorded”, the best mode for carrying out the invention, and the like.

[Mode 6] Furthermore, the printing apparatus of mode 6 is the printing apparatus of any one of modes 1 to 5,
The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
The N-value conversion processing unit generates the third image data obtained by converting the second image data into an N-value based on the nozzle setting information table.

  With such a configuration, for example, when N-value processing using the error diffusion method is performed, the pixel value (minimum density value) in which the nozzle is set to be non-use by the error diffusion method is changed from the surrounding pixels. In the case where the pixel value changes and dots are formed due to the diffusion of the error, the pixel data that is set to non-use based on the nozzle setting information table Thus, the third image data can be generated so as not to form dots even in a state where dots are formed. Therefore, by generating print data from the third image data, it is possible to ensure that dots are not formed at locations where dots are not desired to be formed, so that deterioration in image quality due to banding phenomenon can be further reduced. The effect is obtained.

[Mode 7] Further, the printing apparatus of mode 7 is the printing apparatus of any one of modes 1 to 5,
The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
The printing data generation unit generates the printing data obtained by correcting the third image data based on the nozzle setting information table.

  With such a configuration, for example, when N-value processing using the error diffusion method is performed, when generating the third image data by the error diffusion method, a pixel value in which the nozzle is not used Based on the nozzle setting information table, when the error from the surrounding pixels is diffused to the (minimum density value) and the pixel value changes and dots are formed, it is not used based on the nozzle setting information table. With respect to the pixel data set as, even if it is in a state in which dots are formed, the third image data can be corrected so as not to form dots and print data can be generated. Accordingly, since it is possible to reliably prevent dots from being formed at locations where dots are not desired to be formed, it is possible to obtain an effect of further reducing image quality degradation due to the banding phenomenon.

[Embodiment 8] Furthermore, the printing apparatus according to Embodiment 8 is the printing apparatus according to any one of Embodiments 1 to 5,
The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
The printing unit prints the image on the print medium by the print head based on the printing data and the nozzle setting information table.

  With such a configuration, for example, when N-value processing using the error diffusion method is performed, the pixel value (minimum density value) in which the nozzle is set to be non-use by the error diffusion method is changed from the surrounding pixels. In the case where the pixel value changes and dots are formed due to the diffusion of the error, the pixel data that is set to non-use based on the nozzle setting information table Thus, even if it is in a state where dots are formed, printing can be performed by controlling the print head so as not to form dots. Accordingly, since it is possible to reliably prevent dots from being formed at locations where dots are not desired to be formed, it is possible to obtain an effect of further reducing image quality degradation due to the banding phenomenon.

[Mode 9] Further, the printing apparatus of mode 9 is the printing apparatus of any one of modes 1 to 8,
The print head is a print head in which the nozzles are continuously arranged over a range equivalent to the medium mounting region or a range wider than the mounting region.
With such a configuration, as described above, “white streaks” and “dark streaks” due to the banding phenomenon that is particularly likely to occur when using a line head type print head that finishes printing in one pass is conspicuous. It is possible to generate printing data that can be effectively eliminated.

[Mode 10] Furthermore, the printing apparatus according to mode 10 is the printing apparatus according to any one of modes 1 to 8,
The print head is a print head that performs printing while moving in a direction orthogonal to the paper feed direction of the medium.
The banding phenomenon described above is conspicuous in the case of a line head type print head, but also occurs in the case of a multi-pass type print head. Therefore, if the printing method according to any one of Embodiments 1 to 9 is applied to a multi-pass type print head, “white streaks” and “dark streaks” due to banding phenomenon generated in the multi-pass type print head can also be obtained. There is an effect that it is possible to generate printing data effective to make it inconspicuous.
In the case of a multi-pass type print head, it is possible to avoid the banding phenomenon as described above by taking measures such as repeating scanning of the print head. If the printing apparatus 1 is applied, it is not necessary to scan the same portion over and over again, so that higher-speed printing can be realized.

[Mode 11] On the other hand, in order to achieve the first to third objects, a printing apparatus control program according to mode 11
A printing apparatus control program used to control a printing apparatus configured to print an image on a medium by a print head having a nozzle capable of forming two or more types of dots having different sizes on the medium used for printing. And
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on the stored content of the nozzle information storage means storing nozzle information indicating the characteristics of the nozzle. Nozzle usage information setting step to be set,
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
A printing data generation step for generating printing data defining information relating to the dot formation contents of the nozzle corresponding to the third image data;
And a program used for causing a computer to execute a process including a printing step of printing the image on the medium by the print head based on the printing data.

With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, the same operations and effects as those of the printing apparatus of mode 1 can be obtained.
In addition, most printing devices on the market such as inkjet printers have a computer system including a central processing unit (CPU), a storage device (RAM, ROM), an input / output device, and the like. Since each means can be realized by software, it can be realized more economically and easily than a case where dedicated means is created to realize each means.
Furthermore, it is possible to easily upgrade the version by modifying or improving the function by rewriting a part of the program.

[Mode 12] Furthermore, the printing apparatus control program according to mode 12 is the same as the printing apparatus control program according to mode 11.
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
In the nozzle use information setting step, the nozzle is set to be non-use for all the pixel data corresponding to the nozzle having the ink ejection failure.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operation and effect as those of the printing apparatus according to mode 2 can be obtained.

[Mode 13] Furthermore, the printing apparatus control program according to mode 13 is the printing apparatus control program according to mode 11 or 12,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operation and effect as those of the printing apparatus according to mode 3 can be obtained.

[Form 14] Furthermore, the printing apparatus control program of aspect 14 is the same as the printing apparatus control program of aspect 13.
The nozzle use information setting step is characterized in that the nozzle is set to be unused for a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount.
With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, the same operation and effect as those of the printing apparatus of mode 4 can be obtained.

[Mode 15] Further, the printing apparatus control program according to mode 15 is the printing apparatus control program according to any one of modes 11 to 14,
In the second image data generation step, in the process of distributing the original pixel value, the original pixel value before the change is a random ratio to the pixel value of the pixel image located in the vicinity of the pixel image of the pixel value. It is characterized by distributing with.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operations and effects as those of the printing apparatus of mode 5 are obtained.

[Mode 16] Further, the printing device control program according to mode 16 is the printing device control program according to any one of modes 11 to 15,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the N-value conversion processing step, the third image data obtained by converting the second image data into N-values is generated based on the nozzle setting information table.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operation and effect as those of the printing apparatus of mode 6 can be obtained.

[Mode 17] Further, the printing apparatus control program according to mode 17 is the printing apparatus control program according to any one of modes 11 to 15,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the printing data generation step, the printing data obtained by correcting the third image data based on the nozzle setting information table is generated.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operations and effects as those of the printing apparatus according to mode 7 can be obtained.

[Mode 18] Further, the printing apparatus control program according to mode 18 is the printing apparatus control program according to any one of modes 11 to 15,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the printing step, the image is printed on the print medium by the print head based on the print data and the nozzle setting information table.
In the error diffusion step, if the nozzle having ink ejection failure and the vicinity of the nozzle have such a configuration, the program is read by the computer, and the computer executes the process according to the read program. The same operation and effect as the device can be obtained.

[Mode 19] On the other hand, in order to achieve the first to third objects, a computer-readable recording medium storing the printing apparatus control program according to mode 19 is provided.
The printing apparatus control program according to any one of Form 11 to Form 18 is recorded.
As a result, the same operation and effect as the printing apparatus control program of any one of the eleventh to eighteenth aspects can be obtained, and the printing program can be easily obtained via a recording medium such as a CD-ROM, DVD-ROM, or MO. It is possible to give and receive.

[Mode 20] On the other hand, in order to achieve the first to third objects, a printing apparatus control method according to mode 20 includes:
This is a printing apparatus control method used to control a printing apparatus that prints an image on the medium by a print head having nozzles capable of forming two or more types of dots of different sizes on the medium used for printing. And
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on the stored content of the nozzle information storage means storing nozzle information indicating the characteristics of the nozzle. Nozzle usage information setting step to be set,
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
A printing data generation step for generating printing data defining information relating to the dot formation contents of the nozzle corresponding to the third image data;
And a printing step of printing the image on the medium by the print head based on the printing data.
As a result, the same effect as that of the printing apparatus of aspect 1 can be obtained.

[Form 21] Furthermore, the printing apparatus control method of aspect 21 is the same as the printing apparatus control method of aspect 20.
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
In the nozzle use information setting step, the nozzle is set to be non-use for all the pixel data corresponding to the nozzle having the ink ejection failure.
As a result, the same effect as that of the printing apparatus of aspect 2 can be obtained.

[Mode 22] Further, the printing device control method of mode 22 is the printing device control method of mode 20 or 21,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
As a result, the same effect as that of the printing apparatus according to mode 3 can be obtained.

[Form 23] Furthermore, the printing apparatus control method of aspect 23 is the same as the printing apparatus control method of aspect 22.
The nozzle use information setting step is characterized in that the nozzle is set to be unused for a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount.
As a result, the same effect as that of the printing apparatus of aspect 4 is obtained.

[Mode 24] Furthermore, the printing apparatus control method according to mode 24 is the printing apparatus control method according to any one of modes 20 to 23.
In the second image data generation step, in the process of distributing the original pixel value, the original pixel value before the change is a random ratio to the pixel value of the pixel image located in the vicinity of the pixel image of the pixel value. It is characterized by distributing with.
As a result, the same effect as that of the printing apparatus of mode 5 can be obtained.

[Mode 24] Furthermore, the printing apparatus control method according to mode 24 is the printing apparatus control method according to any one of modes 20 to 24.
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the N-value conversion processing step, the third image data obtained by converting the second image data into N-values is generated based on the nozzle setting information table.
Thereby, the same effect as that of the printing apparatus of mode 6 can be obtained.

[Mode 25] Furthermore, the printing apparatus control method according to mode 25 is the printing apparatus control method according to any one of modes 20 to 24.
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the printing data generation step, the printing data obtained by correcting the third image data based on the nozzle setting information table is generated.
As a result, the same effect as that of the printing apparatus of mode 7 can be obtained.

[Mode 26] Further, the printing device control method of mode 26 is the printing device control method of any one of modes 20 to 24,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the printing step, the image is printed on the print medium by the print head based on the print data and the nozzle setting information table.
As a result, the same effect as that of the printing apparatus of aspect 8 is obtained.

[Mode 27] On the other hand, in order to achieve the first to third objects, the printing data generation apparatus according to mode 27
Printing data for generating printing data used in a printing apparatus that prints an image on the medium by a print head having a nozzle capable of forming two or more types of dots of different sizes on the medium used for printing A generating device,
First image data acquisition means for acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Nozzle information storage means for storing nozzle information indicating the characteristics of the nozzle;
Nozzle use information setting means for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on the nozzle information;
In the first image data, the pixel value of the pixel data set as non-use by the nozzle use information setting unit is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. Second image data generating means for generating second image data distributed to the pixel values of the unprocessed pixels,
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of the pixel data in the second image data into an N (M> N ≧ 2) value. N-value conversion processing means for
Printing data generating means for generating printing data defining information relating to dot formation contents of the nozzle corresponding to the third image data.

That is, this embodiment does not include printing means for actually executing printing as in the printing apparatus, but generates printing data according to the characteristics of the print head based on the original M-value image data. It is what you do.
Accordingly, it is possible to obtain the same operation and effect as the printing apparatus of form 1, and to perform a printing process in the printing apparatus simply by sending the printing data generated in this form to the printing apparatus, for example. With such a configuration, an existing inkjet printing apparatus can be used as it is without preparing a dedicated printing apparatus.
In addition, since a general-purpose information processing device such as a personal computer can be used, an existing printing system including a print instruction device such as a personal computer and an inkjet printer can be used as it is.

[Mode 28] Furthermore, the printing data generation apparatus according to mode 28 is the same as the printing data generation apparatus according to mode 27,
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
The nozzle use information setting means sets the nozzle to non-use for all the pixel data corresponding to the nozzle having the ink ejection failure.
As a result, the same operations and effects as those of the printing apparatus of aspect 2 are obtained.

[Mode 29] Furthermore, the printing data generation device of mode 29 is the printing data generation device of mode 27 or 28,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
As a result, the same operations and effects as those of the printing apparatus of aspect 3 are obtained.

[Mode 30] Furthermore, the printing data generation device of mode 30 is the printing data generation device of mode 29,
The nozzle use information setting unit is characterized in that the nozzle is set not to be used for a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount.
Thereby, the same operation and effect as those of the printing apparatus of aspect 4 can be obtained.

[Mode 31] Furthermore, the printing data generation device according to mode 31 is the printing data generation device according to any one of modes 27 to 30,
In the process of distributing the original pixel value, the second image data generation unit is configured to randomly convert the original pixel value before the change to a pixel value of a pixel image located in the vicinity of the pixel image of the pixel value. It is characterized by distribution.
As a result, the same operations and effects as those of the printing apparatus of aspect 5 are obtained.

[Mode 32] Furthermore, the printing data generation device according to mode 32 is the printing data generation device according to any one of modes 27 to 31,
The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
The N-value conversion processing unit generates the third image data obtained by converting the second image data into an N-value based on the nozzle setting information table.
Thereby, the same operation and effect as those of the printing apparatus of mode 6 can be obtained.

[Mode 33] Furthermore, the printing data generation device according to mode 33 is the printing data generation device according to any one of modes 27 to 31,
The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
The printing data generation unit generates the printing data obtained by correcting the second image data based on the nozzle setting information table.
As a result, the same operations and effects as those of the printing apparatus of aspect 7 are obtained.

[Form 34] Furthermore, the printing data generation device of form 34 is the printing data generation device of any one of forms 27 to 31,
The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
The printing unit prints the image on the print medium by the print head based on the printing data and the nozzle setting information table.
Thereby, the same operation and effect as those of the printing apparatus of aspect 8 can be obtained.

[Mode 35] On the other hand, in order to achieve the above first to third objects, a print data generation program according to mode 35 includes:
Used to generate printing data used in a printing apparatus that prints an image on the medium by a print head having nozzles capable of forming two or more types of dots of different sizes on the medium used for printing. A data generation program for printing
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
A nozzle use information setting step for setting whether to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on nozzle information indicating the characteristics of the nozzle;
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
A program used for causing a computer to execute a process including a printing data generation step for generating printing data defining information relating to dot formation contents of the nozzle corresponding to the third image data is provided. Yes.

  With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, the same operation and effect as those of the form 27 printing data generation apparatus can be obtained.

[Mode 36] Furthermore, the print data generation program of mode 36 is the same as the print data generation program of mode 35,
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
In the nozzle use information setting step, the nozzle is set to be non-use for all the pixel data corresponding to the nozzle having the ink ejection failure.
With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, the same operations and effects as those of the print data generating apparatus of form 28 are obtained.

[Form 37] Furthermore, the print data generation program of form 37 is the print data generation program of form 35 or 36,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operations and effects as those of the printing data generation apparatus according to mode 29 are obtained.

[Mode 38] Furthermore, the printing data generation program of mode 38 is the printing data generation program of mode 37,
The nozzle use information setting step is characterized in that the nozzle is set to be unused for a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operations and effects as those of the printing data generation apparatus according to form 30 are obtained.

[Mode 39] Furthermore, the print data generation program according to mode 39 is the print data generation program according to any one of modes 35 to 38.
In the second image data generation step, in the process of distributing the original pixel value, the original pixel value before the change is a random ratio to the pixel value of the pixel image located in the vicinity of the pixel image of the pixel value. It is characterized by distributing with.
With such a configuration, when the program is read by the computer and the computer executes processing according to the read program, the same operations and effects as those of the printing data generation apparatus of form 31 are obtained.

[Form 40] Furthermore, the print data generation program of form 40 is the print data generation program of any one of forms 35 to 39.
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the N-value conversion processing step, the third image data obtained by converting the second image data into N-values is generated based on the nozzle setting information table.
With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, the same operations and effects as those of the printing data generation apparatus of mode 32 are obtained.

[Form 41] Furthermore, the print data generation program of form 41 is the print data generation program of any one of forms 35 to 39,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
The printing data generation unit generates the printing data obtained by correcting the third image data based on the nozzle setting information table.
With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, the same operations and effects as those of the printing data generation apparatus of form 26 are obtained.

[Mode 42] On the other hand, in order to achieve the first to third objects, a computer-readable recording medium on which the print data generation program according to mode 42 is recorded is provided.
The printing data generation program according to any one of forms 35 to 41 is recorded.
As a result, the same operation and effect as the print data generation program of any one of forms 35 to 41 can be obtained, and the recording medium such as a CD-ROM, DVD-ROM, or FD (flexible disk) can be used. It is possible to easily exchange printing programs.

[Mode 43] On the other hand, in order to achieve the first to third objects, the print data generation method of mode 43 includes:
Printing data for generating printing data used in a printing apparatus that prints an image on the medium by a print head having a nozzle capable of forming two or more types of dots of different sizes on the medium used for printing A generation method,
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
A nozzle use information setting step for setting whether to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on nozzle information indicating the characteristics of the nozzle;
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
And a printing data generation step of generating printing data defining information relating to the dot formation contents of the nozzle corresponding to the third image data.
As a result, the same operations and effects as those of the printing data generation apparatus of form 27 are obtained.

[Form 44] Furthermore, the print data generation method of form 44 is the same as the print data generation method of form 43,
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
In the nozzle use information setting step, the nozzle is set to be non-use for all the pixel data corresponding to the nozzle having the ink ejection failure.
Thus, the same operation and effect as those of the form 28 printing data generation apparatus can be obtained.

[Form 45] Furthermore, the print data generation method of form 45 is the same as the print data generation method of form 43 or 44,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
As a result, the same operation and effect as those of the printing data generation apparatus of form 29 are obtained.

[Form 46] Furthermore, the print data generation method of form 46 is the same as the print data generation method of form 45,
The nozzle use information setting step is characterized in that the nozzle is set to be unused for a part of pixel data corresponding to a nozzle having a positional deviation amount larger than a predetermined amount.
As a result, the same operation and effect as those of the printing data generation apparatus of form 30 can be obtained.

[Form 47] Furthermore, the print data generation method of form 47 is the print data generation method of any one of forms 43 to 46,
In the process of distributing the original pixel value, the second image data generation unit is configured to randomly convert the original pixel value before the change to a pixel value of a pixel image located in the vicinity of the pixel image of the pixel value. It is characterized by distribution.
Thereby, the same operation and effect as those of the printing data generation apparatus of form 31 are obtained.

[Form 48] Furthermore, the print data generation method of form 48 is the print data generation method of any one of forms 43 to 47,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the N-value conversion processing step, the third image data obtained by converting the second image data into N-values is generated based on the nozzle setting information table.
As a result, the same operation and effect as those of the printing data generation apparatus of form 32 are obtained.

[Form 49] Furthermore, the print data generation method of form 49 is the print data generation method of any one of forms 43 to 47,
In the nozzle use information setting step, for each pixel data in the first image data, a nozzle setting information table including information that sets whether to use the nozzle corresponding to each pixel data is generated. And
In the print data generation step, the print data obtained by correcting the second image data based on the nozzle setting information table is generated.
As a result, the same operations and effects as those of the printing data generation apparatus of form 33 are obtained.

[Mode 50] On the other hand, in order to achieve the first to third objects, the nozzle setting information table generation method of mode 50 includes:
Image data having a print head having nozzles capable of forming two or more types of dots of different sizes for printing and corrected using pixel values of pixel data set to disable the nozzles A nozzle setting information table generating method for generating a nozzle setting information table used in a printing apparatus for printing an image on the medium based on printing data generated from
An image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Nozzle use information setting for setting whether to use a nozzle corresponding to each pixel data for each pixel data of the image data acquired in the image data acquisition step based on nozzle information indicating the characteristics of the nozzle Steps,
Nozzle setting for generating a nozzle setting information table in which whether or not to use a nozzle corresponding to each pixel data is set for each pixel data of the image data based on setting information in the nozzle usage information setting step And an information table generation step.

  Therefore, for example, pixel data related to the “banding phenomenon” caused by the characteristics of the nozzle, which is caused by the ink ejection failure at the nozzle or the “flight bending phenomenon” of the nozzle in which the dot formation position deviates from the ideal position. On the other hand, a nozzle setting information table in which the nozzle corresponding to the pixel data is set to be unused for a part or all of the pixel data can be generated, and thus the image data is corrected using this table. In addition, by controlling the printing process, it is possible to appropriately reduce deterioration in print image quality such as “white stripes” and “dark stripes” caused by the banding phenomenon.

[Mode 51] Further, the nozzle setting information table generation method of mode 51 is the same as the nozzle setting information table generation method of mode 50,
The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
In the nozzle setting information generation step, the nozzle is set to be unused for all pixel data corresponding to the nozzle having the ink ejection failure.

  Therefore, the nozzle is set to be unused for all the pixel data corresponding to the nozzle having an ink ejection failure such that the ink cannot be ejected, the ink ejection amount is insufficient, or the ink ejection amount is excessive. Since the nozzle setting information table can be generated, for example, when the pixel data set by using a nozzle corresponds to a nozzle that cannot eject ink, the pixel value is different from the vicinity of the pixel. It is possible to prevent the occurrence of the case where the pixel is not compensated for.

[Mode 52] Furthermore, the nozzle setting information table generation method of mode 52 is the same as the nozzle setting information table generation method of mode 50 or 51,
The nozzle information includes information on a positional deviation amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.
Therefore, whether or not to use the nozzle is appropriately set for pixel data corresponding to the nozzle that causes the so-called “flying curve phenomenon” that occurs when the dot formation position deviates from the ideal formation position. The nozzle setting information table can be generated, and the number of pixel data set to be unused in the nozzle setting information table can be made variable according to the amount of flight curve. The nozzle setting information table suitable for avoiding the “banding phenomenon” that occurs in FIG.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. 1 to 18 show a first embodiment of a printing apparatus, a printing apparatus control program, a printing apparatus control method, a printing data generation apparatus, a printing data generation program, and a printing data generation method according to the present invention. FIG.

First, the configuration of a printing apparatus 100 according to the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a printing apparatus 100 according to the present invention.
The printing apparatus 100 is a line head type printing apparatus, and as illustrated in FIG. 1, a first image data acquisition unit 10 that acquires M image (M ≧ 3) first image data from an external apparatus or a storage medium. Whether or not to use a nozzle is set for each pixel data of the first image data acquired from the first image data acquisition unit 10 based on nozzle information stored in the nozzle information storage unit 12 described later. A nozzle information setting unit 11 that generates a nozzle setting information table, a nozzle information storage unit 12 that stores nozzle information indicating the characteristics of each nozzle N in the print head 200 to be described later, and a nozzle generated by the nozzle information setting unit 11 Based on the nozzle setting information table storage unit 13 for storing the setting information table and the nozzle setting information table generated by the nozzle information setting unit 11, the first image data is stored in the first image data. A second image for generating second image data obtained by changing the pixel value of the pixel data set to not use the nozzle to the lowest density value and distributing the pixel value before the change to the peripheral pixels. The data generation unit 14 is included.

  For example, the first image data acquisition unit 10 has an M value (256 in this case) in which the gradation (luminance value) for each color (R, G, B) per pixel is expressed by 8 bits (0 to 255). ≧ M ≧ 3) has a function of acquiring image data, such image data is acquired from an external device via a network such as a LAN or WAN, or a CD drive (not shown) included in the own device, It can be obtained from a recording medium such as a CD-ROM or DVD-ROM via a drive device such as a DVD drive, or can be obtained from a storage device 70 which will be described later. Further, the M value RGB data is subjected to color conversion processing and converted into M value CMYK (for four colors) data corresponding to each ink of the print head 200 at the same time.

  The nozzle information setting unit 11 performs, based on the nozzle information stored in the nozzle information storage unit 12, for each pixel data constituting the first image data (hereinafter referred to as CMYK image data) converted into CMYK data. Whether or not to use the nozzle corresponding to each pixel data is set, a nozzle setting information table is generated from the setting result, and the generated nozzle setting information table is stored in the second image data generation unit 14 together with the CMYK image data. It is designed to transmit. Further, the nozzle setting information table is stored in the nozzle setting information table storage unit 13.

The nozzle information storage unit 12 is information indicating the correspondence between each nozzle N of the print head 200 of the printing unit 18 and each pixel data in the image data, information indicating the presence or absence of ink ejection failure for each nozzle N, and each nozzle Nozzle information including information indicating the characteristics of the nozzle N, such as information indicating the amount of flight curvature of N, is stored.
Therefore, the nozzle information setting unit 11 sets whether or not to use the nozzle for each pixel data of the first image data according to the ink non-ejection state of the nozzle, the magnitude of the flight bending amount, and the like. .
The nozzle setting information table storage unit 13 stores the nozzle setting information table generated by the nozzle information setting unit 11.

Here, the nozzle setting information table is a table in which whether or not to use the nozzle N corresponding to each pixel data is set for each pixel data of the first image data.
The second image data generation unit 14 acquires the first image data and the nozzle setting information table from the nozzle information setting unit 11, and is set as nozzle non-use in the first image data based on the acquired nozzle setting information table. Change the pixel value of the pixel data to the lowest density value (“0” if the pixel value is a density value, “maximum brightness value (eg, 255)” if the pixel value is a luminance value) The second original image data is generated from the first image data by distributing the previous original pixel value to the peripheral pixels around the pixel that is set not to be used. Further, the generated second image data is transmitted to the N-ary processing unit 15.

  Further, as illustrated in FIG. 1, the printing apparatus 100 applies the second image data generated by the second image data generation unit 14 based on the N-value information stored in the N-value information storage unit 16. Based on the N-value processing unit 15 that performs N (M> N ≧ 2) value processing and the second image data that has been subjected to the N-value processing, the printing unit 18 outputs an image of the second image data as a print medium. A printing data generation unit 17 that generates printing data for printing on (for example, printing paper), and a printing unit 18 that prints an image of the second image data on a printing medium by an inkjet method based on the printing data. It has a configuration that includes.

  The N-value conversion processing unit 15 selects predetermined pixel data from the second image data acquired from the second image data generation unit 14 and is included in the N-value conversion information read from the N-value conversion information storage unit 16. Based on the threshold value for N-value conversion corresponding to each dot formation size, the dot number corresponding to each dot formation size, and the pixel value after N-value conversion corresponding to each dot number (for example, luminance value). Pixel data (hereinafter referred to as selected pixel data) is converted to an N-value using an error diffusion method. That is, the selected pixel data is converted to N-value, and the difference between the pixel value before N-value conversion and the pixel value after N-value conversion of the pixel data is calculated. The peripheral N-value conversion process diffuses unprocessed pixel data.

As described above, by performing N-value conversion and error diffusion processing on all pixel data of the second image data, luminance values and nozzle numbers corresponding to N types of dot formation sizes that can be formed by each nozzle of the print head 200. Convert to data consisting of information. Hereinafter, the second image data after N-value conversion and error diffusion processing is referred to as N-value conversion image data.
Here, N-value conversion means that image data having M values (M ≧ 3) (having M types of pixel values (pixel data)) is converted to N values (M> N ≧ 2) (N types of numerical values). For example, in the case of binarization, the pixel value of the conversion source is compared with a threshold value. If the threshold value is equal to or greater than the threshold value, the numerical value is “1”, and if smaller than the threshold value, the numerical value is “0”. As described above, the pixel value of the conversion source is converted into one of two preset numerical values. Therefore, in the case of N-value conversion, the pixel value of M value is compared with N types of threshold values, and converted into any one of N types of numerical values set in advance according to the comparison result.

  The error diffusion method diffuses errors based on the same principle as the known error diffusion method. For example, the N-value image data may have a pixel value smaller than “128” with a threshold value “128” as a boundary. If the pixel value of the selected pixel is “101” in the case of binarization processing that converts it to “255” if it is “0” or “128” or more, “101” is converted to “0”. The difference “101” between “0” and “101” before conversion is diffused to a plurality of surrounding unprocessed pixels according to a predetermined diffusion method. For example, the pixel right next to the selected pixel (for example, pixel value “101”) is converted to “0” because it is less than the threshold value as in the selected pixel only by the normal binarization process. When, for example, “27”, which is an error of the selected pixel, is received, the pixel value becomes “128”, which exceeds the threshold value “128”, and is thereby converted to “1”.

As described above, the N-value information storage unit 16 stores the N-value threshold corresponding to the dot formation size of the nozzle, the dot number corresponding to each dot formation size, and the N-valued pixel corresponding to each dot number. N-ary information including values (for example, luminance values) is stored.
The print data generation unit 17 outputs N-valued image data composed of nozzle number information (0 to 7) to the print unit 18 as print data, and also sets nozzles according to user settings. Based on the nozzle setting information table stored in the information table storage unit 13, the position where the nozzle number is set not to be used in the table and the dot number for forming the dot is set in the N-valued image data. Printing data corrected to 0 (does not form dots) is generated.

Here, FIG. 3 is a partially enlarged bottom view showing the structure of the print head 200 of the present invention, and FIG. 4 is a partially enlarged side view thereof.
As shown in FIG. 3, the print head 200 includes a black nozzle module in which a plurality of nozzles N (18 in the figure) that exclusively discharge black (K) ink are linearly arranged in the nozzle arrangement direction. 50, and a plurality of nozzles N for discharging yellow (Y) ink exclusively, and a plurality of nozzles 52 for discharging magenta (M) ink exclusively, and a yellow nozzle module 52 arranged linearly in the nozzle arrangement direction. The magenta nozzle module 54 in which the nozzles N are linearly arranged in the nozzle arrangement direction, and a plurality of nozzles N that specifically discharge cyan (M) ink are arranged in a straight line in the nozzle arrangement direction. The configuration includes four nozzle modules 50, 52, 54 and 56 such as the nozzle module 56. As shown in FIG. 3, the nozzle modules 50, 52, 54, and 54 are arranged so that the nozzles N of the same number in these four nozzle modules are aligned in the printing direction (perpendicular to the nozzle arrangement direction). 56 are integrally arranged. Accordingly, the plurality of nozzles N constituting each nozzle module are arranged linearly in the nozzle arrangement direction, and the nozzles N of the same number in the four nozzle modules are arranged linearly in the printing direction.

  Further, FIG. 4 shows that among the four nozzle modules 50, 52, 54, and 56, the black nozzle module 50, the sixth nozzle N6 from the left, has undergone the flight bending phenomenon, and the printing medium starts from the nozzle N6. Ink is ejected obliquely onto S, and the dots formed on the print medium S are thereby ejected from normal nozzles N7 adjacent to the nozzle N6 and in the vicinity of the dots formed on the print medium S. The state where it is formed is shown.

  Returning to FIG. 1, the printing unit 18 starts from the nozzle modules 50, 52, 54 and 56 formed on the print head 200 while moving one or both of the print medium S and the print head 200 shown in FIG. 4. Ink-jet printer in which ink is ejected in the form of dots to form an image composed of a large number of dots on the print medium S. In addition to the print head 200 described above, the print head 200 is connected to the print medium. Print head feeding mechanism (not shown) that reciprocates in the width direction on S (multi-pass type), paper feeding mechanism (not shown) for moving the print medium (paper) S, and printing based on the printing data The printing apparatus includes a print control mechanism (not shown) that controls ink ejection from the head 200.

  The printing apparatus 100 includes a first image data acquisition unit 10, a nozzle information setting unit 11, a second image data generation unit 14, an N-value conversion processing unit 15, a printing data generation unit 16, and a printing unit 18. Are provided with a computer system for executing the software for controlling the hardware necessary for realizing the functions. As shown in FIG. 2, the hardware configuration of the computer system includes a central processing unit (CPU) 60 that is a central processing unit that performs various controls and arithmetic processing, and a RAM (main storage) (main storage). Random Access Memory (ROM) 62 and ROM (Read Only Memory) 64, which is a read-only storage device, are connected by various internal and external buses 68 such as a PCI (Peripheral Component Interconnect) bus and an ISA (Industrial Standard Architecture) bus. In addition, an external storage device (Secondary Storage) 70 such as an HDD, an output device 72 such as a printing unit 20, a CRT, and an LCD monitor, an operation panel and a mouse are connected to the bus 68 via an input / output interface (I / F) 66. A network cable for communication with an input device 74 such as a keyboard, a scanner, and a print instruction device (not shown). Le L is obtained by connecting a.

  When the power is turned on, a system program such as BIOS stored in the ROM 64 or the like is stored in various dedicated computer programs stored in the ROM 64 in advance, or in a CD-ROM, DVD-ROM, flexible disk (FD), or the like. Various dedicated computer programs installed in the storage device 70 are loaded into the RAM 62 via a medium or a communication network such as the Internet, and the CPU 60 executes various resources according to instructions described in the program loaded in the RAM 62. Each function as described above is realized on software by performing predetermined control and arithmetic processing by making full use of.

  Furthermore, in the printing apparatus 100, the CPU 60 activates a predetermined program stored in a predetermined area of the ROM 64, and executes the printing process shown in the flowchart of FIG. 5 according to the program. Note that, as described above, the print head 200 for forming dots can generally form dots of a plurality of types of colors such as four colors and six colors at the same time, but the following example explains the explanation. In order to facilitate the description, it is assumed that each dot is formed by any one (single color) print head 200 (monochrome image).

FIG. 5 is a flowchart illustrating a printing process in the printing apparatus 100.
When the printing process is executed by the CPU 60, as shown in FIG. 5, first, the process proceeds to step S100.
In step S100, the first image data acquisition unit 10 receives print instruction information from the external apparatus connected via the network cable L or the input apparatus 74. Thus, it is determined whether or not there is a print instruction. If it is determined that there is a print instruction (Yes), the process proceeds to step S102. If not (No), the determination process is repeated until there is a print instruction.

  When the process proceeds to step S102, the first image data acquisition unit 10 stores the first image data corresponding to the print instruction as described above, such as an external device, a recording medium such as a CD-ROM or a DVD-ROM, an HDD, or the like. The processing to acquire from the storage device 70 or the like is performed, thereby determining whether or not the first image data has been acquired. If it is determined that the first image data has been acquired (Yes), the process proceeds to step S104; ) Sends a reply indicating that printing is not possible to the print instruction source, and then abandons print processing for the print instruction and moves to step S100. Here, the first image data is data in which a plurality of M-value pixel data are arranged in a matrix, the row direction thereof coincides with the nozzle arrangement direction of the print head 200, and the column direction thereof is printed. This coincides with the printing direction of the head 200.

  When the process proceeds to step S104, in the first image data acquisition unit 10, when the M-value image data acquired in step S102 is image data having color information other than CMYK, the image data is converted to CMYK. While converting to CMYK image data having color information, the CMYK image data is transmitted to the nozzle information setting unit 11, and the process proceeds to step S106. That is, image data having color information other than CMYK is transmitted after CMYK conversion, while CMYK image data is transmitted as it is.

In step S106, when the nozzle information setting unit 11 acquires CMYK image data from the first image data acquisition unit 10, the nozzle information setting process is executed to generate a nozzle setting information table, and together with the generated nozzle setting information table The CMYK image data is transmitted to the second image data generation unit 14, and the process proceeds to step S108.
In step S108, when the CMYK image data and the nozzle setting information table are acquired from the nozzle information setting unit 11 in the second image data generation unit 14, the second image data refinement process is executed to generate the second image data. The generated second image data is transmitted to the N-ary processing unit 15 and the process proceeds to step S110.

In step S110, when the N-value conversion processing unit 15 acquires the second image data from the second image data generation unit 14, the N-value conversion processing is performed on the acquired second image data to generate an N-valued image. Data is generated, the generated N-ary image data is transmitted to the print data generation unit 17, and the process proceeds to step S112.
In step S112, when the print data generation unit 17 acquires the N-value image data from the N-value conversion processing unit 15, print data is generated from the N-value image data, and the process proceeds to step S114. Here, the print data generation unit 17 has a function of generating print data in which the second image data after the N-value conversion processing is corrected in accordance with a correction instruction or correction setting from the user.

In step S114, the printing data generation unit 17 outputs the printing data generated in step S112 to the printing unit 18, and the process proceeds to step S116.
In step S116, the printing unit 18 executes a printing process based on the printing data from the printing data generation unit 17, and proceeds to step S100.

Next, the nozzle information setting process in step S106 will be described in detail with reference to FIG.
FIG. 6 is a flowchart illustrating nozzle information setting processing in the printing apparatus 100.
This nozzle information setting process is a process of generating a nozzle setting information table in which whether or not to use a nozzle corresponding to each pixel data is set for each pixel data of the first image data based on the nozzle information. When executed in step S106, the process first proceeds to step S200 as shown in FIG.

In step S200, nozzle information is read from the nozzle information storage unit 12, and the read nozzle information is stored in a predetermined area of the RAM 62 to acquire the nozzle information, and the process proceeds to step S202.
In step S202, an unset nozzle number corresponding to the first image data is selected from the nozzle information acquired in step S200, and the process proceeds to step S204.

In step S204, based on the ejection / non-ejection information corresponding to the nozzle number selected in step S202, it is determined whether or not the selected nozzle is an ink non-ejection nozzle. The process proceeds to S206, and if not (No), the process proceeds to Step S214.
When the process proceeds to step S206, it is set that the selected nozzle is not used for all pixel data corresponding to the selected nozzle, and the process proceeds to step S208.

In step S208, it is determined whether the setting process has been completed for all nozzles. If it is determined that the setting process has been completed (Yes), the process proceeds to step S210. If not (No), the process proceeds to step S202. To do.
On the other hand, when the process proceeds to step S214, it is determined based on the relative discharge accuracy information (relative flight curve information) included in the nozzle information whether or not the flight curve has occurred in the selected nozzle, and the flight curve has occurred. If it is determined (Yes), the process proceeds to step S216. If not (No), the process proceeds to step S218. In the present embodiment, whether or not to use the nozzle is set for each pixel data based on the data table in which the setting ratio of the used nozzle and the unused nozzle to the flight bending amount is set.

When the process proceeds to step S216, whether or not to use the nozzle is set for the pixel data corresponding to the nozzle based on the flight curve amount of the nozzle where the flight curve has occurred, and the process proceeds to step S208. To do.
On the other hand, when the process proceeds to step S218, it is set that the selected nozzle is used for all pixel data corresponding to the selected nozzle, and the process proceeds to step S220.

In step S208, when the setting process is completed for all nozzles and the process proceeds to step S210, a nozzle setting information table is generated based on the setting result, and the process proceeds to step S212.
In step S212, the nozzle setting information table generated in step S210 is stored in the nozzle setting information table storage unit 13, the series of processes is terminated, and the process returns to the original process.

Next, the second image data generation processing in step S108 will be described in detail based on FIG.
FIG. 7 is a flowchart showing second image data generation processing in the printing apparatus 100.
The second image data generation process changes the pixel value of the pixel data set to the nozzle non-use in the first image data to the lowest density value based on the nozzle setting information table generated in the nozzle information setting unit 11. A process of generating second image data obtained by distributing the original pixel value before the change of the pixel data to the pixel value of a predetermined pixel located in the vicinity of the pixel, which is executed in step S108. As shown in FIG. 7, first, the process proceeds to step S300.

In step S300, it is determined whether or not the first image data and the nozzle setting information table have been acquired from the nozzle information setting unit 11, and if it is determined that they have been acquired (Yes), the process proceeds to step S302; No) continues the judgment process until acquisition.
When the process proceeds to step S302, unprocessed pixel data in the first image data is selected, and the process proceeds to step S304.

In step S304, based on the nozzle setting information table, it is determined whether the pixel data selected in step S302 is set as non-use of nozzles. If it is determined that non-use is set (Yes). Shifts to step S306, otherwise (No) shifts to step S308.
When the process proceeds to step S306, the pixel value of the selected pixel data is changed to the lowest density value (maximum luminance value), and the original pixel value before the change is distributed to the pixel values of the pixels near the selected pixel, and step S308 is performed. Migrate to Here, the distribution of the pixel values is performed, for example, by distributing the original pixel values of the selected pixel data at a random ratio with respect to the pixel values of the pixels located above, below, left, and right of the selected pixel.

In step S308, it is determined whether or not the above process has been completed for all pixel data in the first image data. If it is determined that the process has been completed (Yes), the process proceeds to step S310; ) Proceeds to step S302.
When the process proceeds to step S310, the second image data generated by the pixel value change and distribution processing described above is transmitted to the N-value conversion processing unit 15, the series of processing ends, and the original processing is restored. .

Next, the operation of the present embodiment will be described with reference to FIGS.
Here, FIG. 8 is a diagram showing an example of a dot pattern formed only by the black nozzle module 50 having no so-called abnormal nozzles, and FIG. It is the figure which showed an example of the dot pattern formed when it generate | occur | produces. FIG. 10A is a diagram showing the presence or absence of ink ejection failure (ink non-ejection in the figure) for each nozzle, and FIG. 10B is the relative ejection accuracy information (flight curve amount information) for each nozzle. FIG. FIG. 11A is a view showing a setting information table for ejection / non-ejection (use / non-use) with respect to the relative flight bending amount x, and FIG. It is a figure which shows an example of the setting information in the case of setting. 12 is a diagram showing an example of setting ejection / non-ejection (use / non-use) of nozzles based on the setting information table of FIG. 10, and FIG. 13 shows nozzles when a special flight bending state occurs. It is a figure which shows an example which sets discharge / non-discharge (use / non-use). FIG. 14 is a diagram illustrating an example of a nozzle setting information table. FIG. 15 is a diagram illustrating an example of N value information and threshold information for each N value with respect to the dot size. FIG. 16 is a diagram illustrating an example of an error diffusion matrix used for the N-ary processing. FIG. 17 is a diagram showing an example of a dot pattern when the nozzles are randomly set to non-ejection (non-use) at a ratio of 1/2, and FIG. 18 relates to a special flight curve. It is a figure which shows an example of the dot pattern at the time of setting to make a nozzle non-ejection (non-use) in the ratio of 2/3 with respect to a nozzle.

As shown in FIG. 8, the dot pattern formed by the black nozzle module 50 having no abnormal nozzle has a banding phenomenon that occurs due to the deviation of the nozzle interval such as “white streaks” and “dark streaks” as described above. Does not occur.
On the other hand, as for the printing result by the black nozzle module 50 including the nozzle that generates the flight curve, as shown in FIG. 9, the dot formed by the nozzle N6 is a dot formed by the normal nozzle N7 adjacent to the right. As a result, a “white streak” is generated between the dot formed by the nozzle N6 and the dot formed by the nozzle N5 adjacent to the left side.

On the other hand, when the nozzle modules 52, 54 and 56 corresponding to other colors are used instead of the black nozzle module 50, the nozzle N6 and its nozzle N6 are shifted by the distance a due to the flight curve as described above. Since the distance between the nozzle N7 on the right and the right side becomes closer by the distance a, the density of dots formed by these nozzles increases (the dots may overlap), and this portion is a “dark streak”. As a result, the quality of the printed matter is extremely deteriorated.
The above-mentioned “white streaks” are so-called “solid-colored” printed matter, and when the printing paper is white and the ink is black, etc. The quality of the product will be extremely deteriorated.

  Therefore, in the printing apparatus 100 according to the first embodiment of the present invention, a part of pixel data corresponding to a nozzle that causes a flight curve or a nozzle having ejection failure in the first image data, that is, an abnormal nozzle. Alternatively, the nozzle is set to be non-use for all, and the pixel value of the non-use pixel data is changed to the minimum density value, and the pixel value before the change is changed to the pixel value of a predetermined pixel near the pixel. The distributed second image data is generated, print data is generated from the generated second image data, and printing is performed based on the generated print data, resulting in a print result due to flight bending or ejection failure. It is possible to make “white stripes” or “dark stripes” inconspicuous.

  First, when the first image data acquisition unit 10 receives print instruction information from an external device or the like (step S100), the printing apparatus 100 transmits M-value image data corresponding to the print instruction information to the print instruction information. When the color information of the acquired image data is other than CMYK, it is converted to M-value CMYK image data, while the CMYK image data is transferred to the nozzle information setting unit 11. Transmit (step S104). On the other hand, when the nozzle information setting unit 11 acquires CMYK image data from the first image data acquisition unit 10, the nozzle information setting unit 11 executes nozzle information setting processing (step S106).

  When the nozzle information setting process is started, first, the nozzle information setting unit 11 acquires nozzle information from the nozzle information storage unit 12 (step S200). Here, as shown in FIG. 10A, the nozzle information includes a table of information indicating the presence or absence of ink ejection failure for each nozzle, and a table of information indicating the relative flight bending amount (ejection accuracy) of each nozzle. Are selected from the nozzles corresponding to the first image data (step S202), and the above-described FIG. 10 corresponding to the selected nozzle is selected (step S202). Whether or not the selected nozzle has an ink ejection failure (here, non-ejection) is determined from the information indicating the presence or absence of ejection failure in a) (step S204).

Here, when the selected nozzle has an ink ejection defect (“Yes” branch in step S204), the selected nozzle is set to be not used for all the pixel data corresponding to the selected nozzle. Is performed (step S206).
On the other hand, when there is no ink ejection failure in the selected nozzle (“No” branch in step S204), the selected nozzle is selected based on the information table indicating the relative flight bending amount with respect to each nozzle shown in FIG. To determine whether or not a flight bend occurs (step S214). In this embodiment, whether or not the flight curve is generated by the selected nozzle is determined when the relative flight curve amount x with respect to the selected nozzle shown in FIG. 10B is in the range of “−3 <x ≦ + 3”. Then, it is determined that the flight bend does not occur due to the selected nozzle (“No” branch in step S214), and if it is in the other range, it is determined that the flight bend occurs (“Yes” branch in step S214). . Here, the relative flight bending amount shown in FIG. 10B is obtained when the dot formation position of the selected nozzle is shifted to the left with respect to the ideal position with respect to the arrangement direction of the nozzle modules in the print head 200. Becomes “+” when the sign is shifted to the right side with respect to the ideal position.

  Further, with respect to the selected nozzle that is determined to have a flight curve in the determination process, the selected nozzle is selected based on the contents set in the setting information table for use / non-use for the relative flight curve amount x shown in FIG. When the relative flight bending amount x with respect to is in the range of “x ≦ −6” or “x ≧ + 6”, the selected nozzle is set as non-ejection (unused) for all the row pixels corresponding to the selected nozzle. (Step S206). When the relative flight bending amount x with respect to the selected nozzle is in the range of “−6 <x ≦ −3” or “+3 <x ≦ + 6”, ejection / non-ejection with respect to the selected nozzle shown in FIG. Whether or not to use the selected nozzle is set for each pixel data corresponding to the selected nozzle at a ratio based on the setting information at the time of (use / not use) (step S216).

  That is, as shown in FIG. 11B, when the relative flight bending amount x with respect to the selected nozzle is in the range of “−6 <x ≦ −5” or “+5 <x ≦ + 6”, it corresponds to the selected nozzle. Among the pixel rows to be performed, “1/4” is set as ejection (nozzle use), and the remaining “3/4” is set as non-ejection (no nozzle use). In addition, when the relative flight bending amount x with respect to the selected nozzle is in the range of “−5 <x ≦ −4” or “+4 <x ≦ + 5”, “1/2” in the pixel row corresponding to the selected nozzle. Is set as discharge (nozzle use), and the remaining “1/2” is set as non-discharge (no-nozzle use). Further, when the relative flight bending amount x with respect to the selected nozzle is in the range of “−4 <x ≦ −3” or “+3 <x ≦ + 4”, “3/4” in the pixel row corresponding to the selected nozzle. Is set as discharge (nozzle use), and the remaining “1/4” is set as non-discharge (no nozzle use).

  For example, when the relative flight bending amount x with respect to the selected nozzle is in the range of “−4 <x ≦ −3” and the pixel data of the column number “1” corresponds to the selected nozzle, FIG. As shown in FIG. 12, “0” is set so that ink is ejected (using nozzles) to “3/4” of the pixel data of the column “1” corresponding to the selected nozzle, as shown in FIG. ”And“ 1 ”is set so that the remaining“ 1/4 ”does not eject ink (no nozzles are used). Here, as shown in FIG. 12, the numerical value “0” set for each pixel data indicates the setting for ejecting (using) ink, while the numerical value “1” set for each pixel data. "Indicates that the ink is not ejected (not used).

  Similarly to the above, when the relative flight bend amount x with respect to the selected nozzle is in the range of “−6 <x ≦ −5” and the pixel data of the column number “721” corresponds to the selected nozzle, FIG. Based on the setting information of 11 (b), as shown in FIG. 12, among the pixel data of the column “721” corresponding to the selected nozzle, ink is ejected (using nozzles) to “¼”. “0” is set as described above, and “1” is set so that ink is not ejected (no nozzle is not used) with respect to the remaining “3/4”. Similarly, when the relative flight bending amount x with respect to the selected nozzle is in the range of “+4 <x ≦ + 5” and the pixel data of the column number “1438” corresponds to the selected nozzle, FIG. )), As shown in FIG. 12, “1/2” of the pixel data of the column “1438” corresponding to the selected nozzle is ejected (nozzle is used). “0” is set, and “1” is set so that the remaining “1/2” is not ejected (no nozzle is used).

Further, in the present embodiment, when the left of two adjacent nozzles has a flight curve in the “+” direction and the right nozzle has a flight curve in the “−” direction, 1/3 is set as non-ejection (non-use), and the remaining 2/3 is set as ejection (use) for the column pixels corresponding to the nozzles.
For example, as shown in FIG. 13, when the relative flight bending amount of the left nozzle of the two adjacent nozzles is in the range of “+4 <x ≦ + 5”, normally, as shown in FIG. As shown, “1/2” is set to discharge (nozzle used) in the pixel row corresponding to the selected nozzle, and the remaining “1/2” is set to non-discharge (no nozzle used). Since the relative flight bending amount of the nozzle adjacent to the right side of the nozzle is in the range of “−4 <x ≦ −5”, in this case, “1/3” of the pixel data corresponding to both nozzles is not valid. Discharge is set, and the remaining “2/3” is set to discharge.

In this embodiment, the “discharge / non-discharge (use / non-use)” of the selected nozzle set in the range of the relative flight bending amount x of the selected nozzle shown in FIG. The setting process using the setting ratio is performed by setting the use / non-use of the nozzles for the pixel data at random positions so that the setting ratio is obtained.
Then, the nozzle information setting unit 11 sets the “ejection / non-ejection (use / non-use)” setting process for the selected nozzle as described above for all the nozzles used for printing the first image data. When the processing is finished, a nozzle setting information table as shown in FIG. 14 is generated based on the setting information (step S210), and the generated nozzle setting information table together with the first image data is generated in the second image data generation unit 14. Further, the generated nozzle setting information table is stored in the nozzle setting information table storage unit 13 (step S212).

Here, when the nozzles are in an ejection failure state in which ink cannot be ejected physically, as shown by the column number “720” in FIG. 14, all the pixel data in the columns corresponding to the ejection failure nozzles are not valid. Discharge “1” is set.
On the other hand, when the second image data generation unit 14 acquires the nozzle setting information table and the first image data from the nozzle information setting unit 11 ("Yes" branch of step S300), the second image data generation unit 14 determines from the acquired first image data: Pixel data that has not been changed or distributed is selected (step S302), and based on the acquired nozzle setting information table, whether or not a nozzle is not ejected (not used) for the selected pixel data. It is determined whether or not (step S304).

  Here, in the nozzle setting information table, when the non-ejection “1” is set for the selected pixel data (“Yes” branch in step S304), for example, the pixel value of the selected pixel data ( (Luminance value) is “60”, the luminance value “60” is changed to “255” which is the maximum luminance value of the first image data, and the luminance value “60” before the change is selected. The pixel data is distributed to pixel values of pixels located in the vicinity of the pixel (step S306). In the present embodiment, this distribution process distributes a pixel at a random ratio to pixels that are adjacent to the selected pixel in the upper, lower, left, and right directions, and for which the nozzle is set to discharge (nozzle use). For example, when the luminance values of the pixels adjacent to the selected pixel in the upper, lower, left, and right directions are “40”, “30”, “160”, and “200” on the right, the luminance value “60−” of the selected pixel data is displayed. 255 = −195 ”, for example,“ −5 ”for the upper luminance value,“ −5 ”for the lower luminance value,“ −60 ”for the left luminance value, and“ −125 ”for the right luminance value. Distribute at a reasonable rate. Therefore, the pixel value of the upper pixel of the selected pixel is “40-5 = 35”, the pixel value of the lower pixel is “30-5 = 25”, and the pixel value of the left pixel is “160-60 = 100”. ", And the pixel value of the right pixel is" 200-125 = 75 ". Here, for example, when the pixel above the selected pixel is also set as non-ejection (no-nozzle use), “−5” distributed to the upper pixel is set to one of the other three pixels. Will be distributed to.

  In this way, the process of setting the pixel value of the pixel data set as non-ejection (no nozzle use) to the maximum luminance value and distributing the original pixel value to the pixel values of the pixels in the vicinity of the selected pixel, When the process is completed for all non-ejection (no-nozzle use) pixel data of one image data ("Yes" branch in step S308), the first image data after the pixel value change and distribution processing is changed to the second image data. The image data is transmitted to the N-ary processing unit 15 (step S310).

When acquiring the second image data from the second image data generation unit 14, the N-value conversion processing unit 15 reads the N-value information from the N-value information storage unit 16, and based on the read N-value information. N-value processing is performed on each pixel data of the second image data to generate N-value image data (step S110).
That is, when acquiring the N-value information, the N-value processing unit 15 selects pixel data that has not been subjected to the N-value processing from the second image data, and sets the value of the selected pixel data of the M value to the value described above. Based on the acquired N-value information, it is converted to an N value.

  In the present embodiment, when the original pixel value (luminance (or density)) of the selected pixel data is 8-bit “256” gradation, the N-value conversion processing is performed as shown in FIG. When the value is less than “0” to “32”, the pixel values are grouped into “0”, the N value is set to “7” corresponding to the dot number, and the original pixel values are “32” to “64”. When the pixel value is less than “64”, the pixel value is grouped into “36” and the N value is set to “6” corresponding to the dot number, and when the original pixel value is less than “64” to “96”, the pixel value Are integrated into “73” and the N value is set to “5” corresponding to the dot number. Similarly, when the original pixel value is less than “96” to “128”, the pixel value is grouped into “109”, the N value is set to “4” corresponding to the dot number, and the original pixel value is set. Is less than “128” to “159”, the pixel values are grouped into “146”, the N value is set to “3” corresponding to the dot number, and the original pixel values are “159” to “191”. When the pixel value is less than “191”, the pixel value is grouped into “182” and the N value is set to “2” corresponding to the dot number. Further, when the original pixel value is less than “191” to “223”, the pixel value When the original pixel values are “223” to “255”, the pixel values are grouped into “255” and the N value is used as a dot number. Corresponding “0” is set.

The above example is a case where the luminance is adopted as the pixel value. When the density is adopted as the pixel value, as shown in parentheses in the figure, each luminance value is changed from the opposite value of each luminance ("255"). Subtracted value).
Further, when the selected pixel data is converted to an N value, the N-value conversion processing unit 15 calculates an error between the luminance value before conversion of the selected pixel data and the luminance value corresponding to the dot number after conversion. The calculated error is diffused to the unprocessed pixels by the N-value conversion process around the pixels of the selected pixel data. The process of diffusing this error is performed based on an error diffusion matrix as shown in FIG.

Therefore, the selected pixel data is converted into an N value by the N value conversion process and the error diffusion process, and the pixel value of the unprocessed pixel data around the selected pixel data is converted into an N value. Updated to reflect the error that occurred. Thereafter, the N-value conversion and the error diffusion process are sequentially performed on the unprocessed pixel data updated in this way.
Then, the above-described N-value conversion processing and error diffusion processing are performed on all pixel data of the second image data, and the N-value conversion image data after the N-value conversion processing is transmitted to the print data generation unit 17.

  When the print data generation unit 17 acquires the N-valued image data from the N-value conversion processing unit 15, the nozzle setting information stored in the nozzle setting information table storage unit 13 is set when correction processing is set. Based on the table, print data is generated by correcting the acquired N-valued image data. However, in this embodiment, the correction processing is not set, and the N-valued image data is printed. As print data (step S112), the print data is output to the printing unit 18 (step S114). Note that correction processing of N-valued image data with respect to the setting of correction processing will be described in [Second Embodiment] as a modification of the first embodiment.

On the other hand, the printing unit 18 acquires the printing data output from the printing data generation unit 17 and corresponds to each dot number on the printing medium using the black nozzle module 50 based on the acquired printing data. A dot having the size is formed (printed) (step S116).
As a technical method for controlling the dot size in this way, for example, in the case of a method using a piezo actuator for the print head, the voltage applied to the piezo element is changed to control the ink ejection amount. This makes it easy to implement.

  As described above, as shown in FIGS. 11 (a) and 11 (b), the pixel data at the location where the banding phenomenon occurs due to the flying curve phenomenon of the nozzle or the ink ejection failure of the nozzle is set in advance as shown in FIGS. According to the set ratio information of the discharge / non-discharge (use / non-use) of the nozzle corresponding to the flying curve amount, the discharge / non-discharge of the nozzle is performed on the pixel data corresponding to the nozzle where the flight curve occurs. By setting the ejection (use / non-use), it is possible to make the phenomenon visually recognized as white stripes or dark stripes less conspicuous than the dot pattern formation result shown in FIG.

  Specifically, for example, as shown in FIG. 17A, the dot formation position of the nozzle is shifted to the right from the ideal position due to the flight curve, and the dot of the row pixel of this nozzle is changed to the row pixel of the adjacent nozzle. In the case where the dot overlaps with the dot, the nozzle information setting unit 11 assumes that the relative flight bending amount x of the nozzle is in the range of “+4 <x ≦ + 5”. According to the setting information shown in FIG. 11B, “1/2” is set as ink non-ejection (no nozzle use) for the pixel, and the remaining “1/2” is ink ejection (nozzle use). ) Is set. When the second image data is generated in the second image data generation unit 14 with the contents set as described above, the print result of the print data after the N-value conversion processing is as shown in FIG. In the above setting, since dots are not formed for half of the row pixels corresponding to the nozzles that generate the flight curve, the “dark streaks” caused by the flight curve are alleviated, and the banding becomes inconspicuous. Yes.

  Also, for example, as shown in FIG. 18 (a), two adjacent nozzles are deflected by flight, the left nozzle shifts the dot formation position to the right, and the right nozzle shifts the dot formation position to the left. In the nozzle information setting unit 11, the relative flight bending amount x of the left nozzle is in the range of “+4 <x ≦ + 5”, and when both the dots are overlapped, and Assuming that the relative flight curvature x on the right side is in the range of “−5 <x ≦ −4”, in this case, as an exception process, for each row pixel corresponding to both nozzles, / 3 is set as non-discharge, and the remaining 2/3 is set as discharge. When the second image data is generated in the second image data generation unit 14 with the contents set as described above, the print result of the print data after the N-value conversion processing is as shown in FIG. Because of the above settings, dots are not formed for 1/3 of the row pixels corresponding to the nozzles that generate flight bends, so that “dark streaks” caused by flight bends are alleviated and banding becomes inconspicuous. Yes.

  In the example of FIG. 18 (a), both nozzles that generate flight bends are ½ or more of the column pixels corresponding to these adjacent nozzles according to the setting information shown in FIG. 11 (b). If non-ejection is set for the pixel, there may be a situation where the gradation for the non-ejection cannot be compensated for by surrounding pixels. Therefore, in the present embodiment, when the flight bend occurs in both of the two adjacent nozzles as described above, the number set as non-ejection is limited as an exception.

Furthermore, based on FIGS. 19-22, the effect of this invention is demonstrated more concretely, giving an Example.
Here, FIG. 19 is a gradation image used in the embodiment. FIG. 20 shows the error diffusion matrix used in the example. FIG. 21 shows the gradation image shown in FIG. 19 by simply using the error diffusion matrix shown in FIG. 20 without using the method according to the present invention. It is a figure which shows the result of valuation. FIG. 22 is a diagram showing the result of quaternarizing the gradation image of FIG. 19 using the technique according to the present invention. The “error diffusion matrix” is a difference (error) between the N value after conversion and the M value before conversion when the pixel data of the M value is converted to N value in the N-value conversion process. The position of the pixel data to be diffused with respect to the original pixel data when the N-value conversion processing around the pixel data is diffused (distributed) into unprocessed pixel data (this is generally called error diffusion method). This is a matrix that contains information indicating the (diffusion direction) (relative position information, etc.), information on the diffusion ratio for each pixel data to be diffused, etc. The shape of the matrix, the size of the matrix (number of diffusion objects), the diffusion ratio, etc. There are various types of error diffusion matrices that differ from each other.

First, an image after quaternarization by a conventional method will be described.
An image obtained by converting the gradation image into a four-valued image by a conventional method is as shown in FIG. When attention is paid to the image portions 21a to 21c in the gradation image after quaternarization shown in FIG. 21, in the image portion 21a, the types of dots at the time of printing (dots have a plurality of sizes). Since switching is not performed smoothly and a dot type switching delay occurs, dots are formed so as to flow in the lower right direction particularly in a circled portion. Further, in the image portion 21b (halftone portion), for the same reason as 21a, a plurality of types of dots forming this portion are not uniformly mixed, so that the image quality is deteriorated. In addition, in the image portion 21c, for the same reason as in 21a and 21b, a so-called dot tailing phenomenon in which dots flow in the lower right direction has occurred particularly in the circled portion.

Each phenomenon occurring in the enlarged image portions 21a to 21c described above deteriorates the image quality of the gradation image.
On the other hand, the result of performing quaternization and error diffusion processing on the gradation image shown in FIG. 19 using the method of the present invention shown in FIG. 16 is as shown in FIG. When attention is paid to the image parts 23a to 23c in the gradation image after quaternarization shown in FIG. 22, in the image part 23a, the dot type switching delay is improved as compared with the conventional method, and the dot type of the shadow part is improved. Is improved, and the image quality is improved as compared with the image portion 21a of FIG. Further, in the image portion 23b, a plurality of types of dots are uniformly mixed as compared with the conventional method, and the image quality is improved as compared with the image portion 21b in FIG. Further, in the image portion 23c, the dot tailing phenomenon in the highlight portion is improved as compared with the conventional method, and the image quality is improved as compared with the image portion 21c in FIG.

  In the first embodiment, the first image data acquisition unit 10 corresponds to the image data acquisition unit of the form 1 or 21, and the nozzle information storage unit 12 is any one of the forms 1, 9, 16, and 22. The nozzle information setting unit 11 and the nozzle setting information storage unit 13 correspond to the nozzle usage information setting unit of any one of the forms 1, 3, 22, and 24, and generate the second image data. The unit 14 corresponds to the second image data generation unit of any one of modes 1, 4, 22, 25, and 37, and the N-value conversion processing unit 15 and the N-value conversion information storage unit 16 are the same as those in the mode 1 or 22. Corresponding to the N-value conversion processing means, the print data generation unit 17 corresponds to the print data generation means of any one of the forms 1, 5 and 22, and the print unit 18 corresponds to the print means of the form 1 or 6. Correspond.

  In the first embodiment, steps S102 and S104 correspond to the first image data acquisition step of any one of forms 9, 16, and 28, and step S106 includes forms 9, 11, 16, 18, 28. , 30, 32, 34, 36, and 39, corresponding to the nozzle use information setting step, step S108 is the second image of any one of the forms 9, 12, 16, 19, 28, 31 and 34. Corresponding to the data generation step, step S110 corresponds to the N-ary processing step of any one of forms 9, 16, 28 and 34, and step S112 corresponds to those of forms 9, 13, 16, 20, 28 and 34. Corresponding to any one of the print data generation steps, Step S116 corresponds to any one of the printing steps of forms 9, 14, 16 and 20.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings. 23 and 24 show a second embodiment of a printing apparatus, a printing apparatus control program and a printing apparatus control method, and a printing data generation apparatus, a printing data generation program and a printing data generation method according to the present invention. FIG.
The configuration of the printing apparatus and the computer system according to the present embodiment is the same as that shown in FIGS. 1 and 2 of the first embodiment. In the present embodiment, N-valued image data correction processing shown in FIG. 23 is performed in the print data generation processing performed in step S112 in FIG. 5 of the first embodiment.

  In the correction processing of the N-valued image data in FIG. 23, the pixel value of the pixel data in which the nozzle information setting unit 11 sets the ink to non-ejection (no nozzle use) and changes the pixel value to the minimum density value is obtained. When the error diffusion process in the N-value conversion processing unit 15 receives an error from a peripheral pixel and changes to a pixel value for forming a dot, the print data generation unit 17 stores the nozzle setting information table. This is processing for correcting N-valued image data based on the nozzle setting information table stored in the unit 13. That is, in the N-valued image data, the pixel data that is in a state of forming dots while being set as ink non-ejection is changed to a state of not forming dots.

Hereinafter, only different parts from the first embodiment will be described, and description of parts overlapping with the first embodiment will be omitted.
Based on FIG. 23, the print data generation processing in step S112 in the present embodiment will be described in detail.
FIG. 23 is a flowchart illustrating print data generation processing in the print data generation unit 17 of the printing apparatus 100.

When the print data generation process is executed in step S112, as shown in FIG. 23, first, the process proceeds to step S400.
In step S400, it is determined whether or not N-valued image data has been acquired from the N-value conversion processing unit 15. If it is determined that it has been acquired (Yes), the process proceeds to step S402, and if not (No). The judgment process continues until it is acquired.

When the process proceeds to step S402, it is determined whether or not there is an instruction to perform correction (correction setting). When it is determined that there is an instruction (Yes), the process proceeds to step S404. The process is terminated and the process returns to the original process. That is, when there is no correction instruction, it is the same as in the first embodiment.
When the process proceeds to step S404, the nozzle setting information table is read from the nozzle setting information table storage unit 13, and the nozzle setting information table is acquired by storing the read nozzle setting information table in a predetermined area of the RAM 62. The process proceeds to S406.

In step S406, pixel data that has not been subjected to correction processing is selected from the N-valued image data, and the process proceeds to step S408.
In step S408, based on the nozzle setting information table, it is determined whether or not non-ejection (non-use) is set for the selected pixel data, and it is determined that non-ejection (non-use) is set. If (Yes), the process proceeds to step S410. If not (No), the process proceeds to step S412.

When the process proceeds to step S410, it is determined whether or not the value of the selected pixel data is “0”. When it is determined that it is “0” (Yes), the process proceeds to step S414, and when it is not (No). Proceeds to step S412. That is, it is determined whether or not the pixel data value is the nozzle number “0” (no dot).
If the process proceeds to step S412, the value of the selected pixel data is changed to “0”, and the process proceeds to step S414.
On the other hand, if the process proceeds to step S414, it is determined whether or not the process has been completed for all the pixel data. If it is determined that the process has been completed (Yes), the series of processes is terminated and the original process is performed. If not (No), the process proceeds to step S406.

  Next, the operation of the present embodiment will be described with reference to FIG. Here, FIG. 24A is a diagram showing an ideal dot formation pattern by non-ejection setting, and FIG. 24B is a diagram showing an example in which dots are formed in the non-ejection portion by error diffusion.

  The print data generation process in the present embodiment is started by acquiring the N-valued image data from the N-value conversion processing unit 15 in the print data generation unit 17 (“Yes” branch of step S400). First, it is determined whether or not the setting for performing the correction process is made (step S402). When there is a correction instruction from the user or the like by this determination and the setting for performing the correction instruction is made (“Yes” in step S402), the nozzle setting information table is stored in the nozzle setting information table storage unit 13. The data is read out and stored in a predetermined area of the RAM 62 (step S404), and pixel data that has not been subjected to correction processing is selected from the N-valued image data (step S406). After selecting the pixel data, the print data generation unit 17 then makes the nozzle corresponding to the selected pixel data non-ejection (unused) with respect to the selected pixel data based on the acquired nozzle setting information table. It is determined whether or not the setting has been made (step S408). That is, when “1” is set in the nozzle setting information table for the selected pixel data, non-ejection is set. On the other hand, when “0” is set, ejection is set. become.

  When non-ejection is set for the selected pixel data (“Yes” branch in step S408), the value of the selected pixel data is “0” corresponding to “no dot” in the nozzle number. Is determined (step S410). In other words, when the value of the selected pixel data is other than “0” although it is set as non-ejection (“No” branch in step S410), a dot is formed for the selected pixel data. Therefore, the value of the selected pixel data is changed to “0” in order not to form dots (step S412).

Specifically, for example, as illustrated in FIG. 24B, the pixel value of a pixel that has received an error from a peripheral pixel due to error diffusion processing is changed, so that, for example, as illustrated in FIG. In the case where a dot A is originally formed where a dot should not be formed, the value of the pixel data that forms this dot A is changed to “0”, so that FIG. As described above, since the dots A are not formed, it is possible to form a target dot pattern.
Then, by performing the determination process and the correction process on all the pixel data of the N-valued image data (“Yes” branch in step S414), print data is generated.

  In the present embodiment, the dot of the pixel data is changed with respect to the pixel data in which the dot is formed due to the influence of the error diffusion process even though the non-ejection is set. In order to prevent the image data from being formed, print data obtained by correcting the N-valued image data is generated on the basis of the nozzle setting information table, but this is not a limitation. By forming dots while referring to the nozzle setting information table, it is possible to perform control so as not to form dots even if the value of the pixel data set as non-ejection is other than “0”. Thus, it is possible to ensure that dots of pixel data set as non-ejection are not reliably formed.

  In the second embodiment, the first image data acquisition unit 10 corresponds to the image data acquisition unit of the form 1 or 21, and the nozzle information storage unit 12 is any one of the forms 1, 9, 16, and 22. The nozzle information setting unit 11 and the nozzle setting information storage unit 13 correspond to the nozzle information storage unit of any one of forms 1, 3, 5, 6, 22, 24, 26, and 27. Correspondingly, the second image data generating unit 14 corresponds to any one of the second image data generating means of any one of forms 1, 4, 22 and 25, and the N-value conversion processing unit 15 and the N-value conversion information storage unit 16 are The print data generation unit 17 corresponds to the print data generation unit of any one of modes 1, 5, 22 and 26, and the print unit 18 This corresponds to the printing means of form 1 or 6.

  In the second embodiment, Steps S102 and S104 correspond to the first image data acquisition step of any one of Embodiments 9, 16, 28, and 36, and Step S106 includes Embodiments 9, 11, 13, and 14. 16, 16, 20, 21, 28, 30, 32, 34, 36, 38, and 39, corresponding to the nozzle use information setting step, step S 108 is a mode 9, 12, 16, 19, 28. , 31 and 34 correspond to the second image data generation step of any one of the above, step S110 corresponds to any one of the N-value conversion processing steps of the forms 9, 16, 28 and 34, and the step S112 corresponds to the form. In response to the print data generation step of any one of 9, 13, 16, 20, 28, and 34, the step S116 is the mark of any one of the forms 9, 14, 16, and 20. Corresponding to the step.

  Note that the printing apparatus according to the first and second embodiments is characterized in that the printing data is generated from the image data in accordance with the characteristics of the printing head with almost no modification to the existing printing apparatus itself. Therefore, it is not necessary to prepare a special printer as the printing unit 18, and an existing inkjet printer can be used as it is. If the printing unit 12 is separated from the printing apparatus 100 in the above embodiment, the function can be realized only by a general-purpose printing instruction terminal (printing data generation apparatus) such as a PC.

The printing apparatus 100 according to the first and second embodiments may be realized as a network system that is communicably connected to an existing inkjet printer and other apparatuses, terminals, devices, and the like. . In this case, the first image data acquisition unit 10, the nozzle information setting unit 11, the nozzle information storage unit 12, the nozzle setting information table storage unit 13, the second image data generation unit 14, the N-value conversion processing unit 15, and the N-value information The storage unit 16 and the print data generation unit 17 may belong to any of other devices, terminals, devices, and the like.
Further, the present invention is not limited to the flying bend phenomenon, but the ink ejection direction is vertical (normal), but the formation content of the nozzle is deviated from the normal position. As a result, the dots formed are the same as the flying bend phenomenon. Of course, the present invention can be applied in exactly the same manner.

  The printing apparatus 100 in the first and second embodiments can be applied not only to a line head type ink jet printer but also to a multi-pass type ink jet printer. It is possible to obtain high-quality printed material with almost no noticeable white or dark streaks in one pass even if the flight bend phenomenon occurs. Since it can be reduced, high-speed printing is possible than before.

FIGS. 25A to 25C show respective printing systems using a line head type ink jet printer and a multi-pass type ink jet printer.
As shown in FIG. 4A, when the width direction of the rectangular printing paper S is the main scanning direction of the image data and the longitudinal direction is the sub-scanning direction of the image data, the line head type inkjet printer As shown in (B), the print head 200 has a length corresponding to the paper width of the print paper S, the print head 200 is fixed, and the print paper S is sub-scanned with respect to the print head 200. By moving in the direction, printing is completed in a so-called one scan (one-pass operation). Note that it is also possible to perform printing while fixing the printing paper S and moving the print head 200 side in the sub-scanning direction, or moving both in the opposite direction as in a so-called flat head type scanner. . On the other hand, in the multi-pass type ink jet printer, as shown in FIG. 5C, the print head 200, which is much shorter than the paper width, is positioned in the direction perpendicular to the main scanning direction. Printing is executed by moving the printing paper S in the sub-scanning direction by a predetermined pitch while reciprocating in the main scanning direction many times. Therefore, the latter multi-pass type ink jet printer has a drawback that it takes more printing time than the former line head type ink jet printer, but the print head 200 can be repeatedly positioned at an arbitrary position. Among the banding phenomenon as described above, it is possible to cope to some extent with respect to the reduction of the white streak phenomenon.

In the first and second embodiments, the ink jet printer that performs printing by ejecting ink in the form of dots has been described as an example. However, the present invention provides a print head in which the print mechanisms are arranged in a line. The present invention can also be applied to other printing apparatuses used, for example, thermal head printers called thermal transfer printers or thermal printers.
In FIG. 3, each nozzle module 50, 52, 54, 56 provided for each color of the print head 200 has a form in which nozzles N are linearly continued in the longitudinal direction of the print head 200. 26, each of these nozzle modules 50, 52, 54, 56 is composed of a plurality of short nozzle units 50a, 50b,... 50n, which are arranged before and after the print head 200 in the moving direction. You may comprise as follows. In particular, if each of the nozzle modules 50, 52, 54, 56 is composed of a plurality of short nozzle units 50a, 50b,... 50n, the distance between the actual dots of the nozzle units 50a, 50b,. Since the distance between dots can be substantially shortened without reducing (pitch), it is possible to easily cope with a high-resolution image.

1 is a block diagram illustrating a configuration of a printing apparatus 100 according to the present invention. It is a figure which shows the hardware constitutions of a computer system. It is a partial expanded bottom view which shows the structure of the print head 200 of this invention. FIG. 5 is a partially enlarged side view of FIG. 4. 3 is a flowchart illustrating a printing process in the printing apparatus 100. 4 is a flowchart illustrating nozzle information setting processing in the printing apparatus 100. 4 is a flowchart illustrating second image data generation processing in the printing apparatus 100. It is the figure which showed an example of the dot pattern formed only with the black nozzle module 50 without the abnormal nozzle which generate | occur | produces a flight curve. It is the figure which showed an example of the dot pattern formed when the nozzle N6 has generate | occur | produced the flight bending phenomenon among the black nozzle modules. (A) is a figure which shows the presence or absence of the discharge failure of ink with respect to each nozzle (in the figure, ink non-discharge), and (b) is a figure which shows the relative discharge accuracy information (flight curve amount information) with respect to each nozzle. Ah. (A) is a figure which shows the setting information table of discharge / non-discharge (use / non-use) with respect to the relative flight bending amount x, and (b) is a case where discharge / non-discharge (use / non-use) is set. It is a figure which shows an example of the setting information. It is a figure which shows an example which sets discharge / non-discharge (use / non-use) of a nozzle based on the setting information table of FIG. It is a figure which shows an example which sets discharge / non-discharge (use / non-use) of a nozzle with respect to the time of a special flight bending state occurrence. It is a figure which shows an example of a nozzle setting information table. It is a figure which shows an example of the information of N value with respect to dot size, and the information of the threshold value with respect to each N value. It is a figure which shows an example of the error diffusion matrix used for an N-value-izing process. It is a figure which shows an example of the dot pattern at the time of setting a nozzle to non-ejection (nonuse) at a ratio of 1/2. It is a figure which shows an example of the dot pattern at the time of setting to make a nozzle non-ejecting (non-use) with the ratio of 2/3 with respect to a related nozzle with respect to special flight bending. It is the gradation image used in the present Example. It is the error diffusion matrix used in the example. FIG. 21 is a diagram showing a result of simply quaternizing the gradation image of FIG. 19 using the error diffusion matrix shown in FIG. 20 without using the method according to the present invention. It is a figure which shows the result of having binarized the gradation image of FIG. 19 using the method which concerns on this invention. 4 is a flowchart illustrating print data generation processing in a print data generation unit 17 of the printing apparatus 100. (A) is a figure which shows the ideal dot formation pattern by non-ejection setting, (b) is a figure which shows an example in which the dot was formed in the non-ejection part by error diffusion. (A)-(C) is explanatory drawing which shows the difference in the printing system by a multipass type inkjet printer and a line head type inkjet printer. It is a conceptual diagram which shows the other example of the structure of a print head.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Printing apparatus, 200 ... Print head, 10 ... 1st image data acquisition part, 11 ... Nozzle information setting part, 12 ... Nozzle information storage part, 13 ... Nozzle setting information table storage part, 14 ... 2nd image data generation part 15 ... N-value processing unit, 16 ... N-value information storage unit, 17 ... Print data generation unit, 18 ... Print unit, 60 ... CPU, 62 ... RAM, 64 ... ROM, 66 ... Interface, 70 ... Storage Device ... 72 ... Output device 74 ... Input device 50 ... Black nozzle module 52 ... Yellow nozzle module 54 ... Magenta nozzle module 56 ... Cyan nozzle module P, S ... Printing medium (paper), L ... Network cable , N ... Nozzle

Claims (16)

A printing apparatus configured to print an image on the medium by a print head having a nozzle capable of forming two or more types of dots having different sizes on a medium used for printing,
First image data acquisition means for acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Nozzle information storage means for storing nozzle information indicating the characteristics of the nozzle;
Nozzle use information setting means for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data of the first image data based on the nozzle information;
In the first image data, the pixel value of the pixel data set as non-use by the nozzle use information setting unit is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. Second image data generating means for generating second image data distributed to the pixel values of the unprocessed pixels,
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of the pixel data in the second image data into an N (M> N ≧ 2) value. N-value conversion processing means for
Print data generation means for generating print data defining information relating to dot formation contents of the nozzle corresponding to the third image data;
And a printing unit configured to print the image on the medium by the print head based on the printing data. The nozzle information includes information indicating the presence or absence of ink ejection failure of the nozzle,
The printing apparatus according to claim 1, wherein the nozzle use information setting unit sets the nozzle to be unused for all of the pixel data corresponding to the nozzle having the ink ejection failure.   The printing apparatus according to claim 1, wherein the nozzle information includes information on a displacement amount between an actual formation position of the dot of the nozzle and an ideal formation position of the dot.   The printing apparatus according to claim 3, wherein the nozzle use information setting unit sets the nozzle to be unused with respect to a part of pixel data corresponding to a nozzle having the positional deviation amount larger than a predetermined amount.   In the process of distributing the original pixel value, the second image data generating means randomly converts the original pixel value before the change to a pixel value of a pixel image located in the vicinity of the pixel image of the pixel value. The printing apparatus according to claim 1, wherein the printing apparatus distributes the printing apparatus. The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
6. The N-value conversion processing unit generates the third image data obtained by converting the second image data into an N-value based on the nozzle setting information table. The printing apparatus according to item. The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
6. The print data generation unit generates the print data obtained by correcting the third image data based on the nozzle setting information table. The printing apparatus as described. The nozzle use information setting means generates a nozzle setting information table composed of information for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data. And
6. The printing device according to claim 1, wherein the printing unit prints the image on the medium by the print head based on the printing data and the nozzle setting information table. Printing device.   The print head is a print head in which the nozzles are continuously arranged over a range equivalent to the medium mounting region or a range wider than the mounting region. The printing apparatus according to any one of the above.   The printing apparatus according to claim 1, wherein the print head is a print head that performs printing while moving in a direction orthogonal to a paper feeding direction of the medium. A printing apparatus control program used to control a printing apparatus configured to print an image on a medium by a print head having a nozzle capable of forming two or more types of dots having different sizes on the medium used for printing. And
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on the stored content of the nozzle information storage means storing nozzle information indicating the characteristics of the nozzle. Nozzle usage information setting step to be set,
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
A printing data generation step for generating printing data defining information relating to the dot formation contents of the nozzle corresponding to the third image data;
A printing apparatus control program comprising: a program used for causing a computer to execute a process including a printing step of printing the image on the medium by the print head based on the printing data. This is a printing apparatus control method used to control a printing apparatus that prints an image on the medium by a print head having nozzles capable of forming two or more types of dots of different sizes on the medium used for printing. And
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on the stored content of the nozzle information storage means storing nozzle information indicating the characteristics of the nozzle. Nozzle usage information setting step to be set,
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
A printing data generation step for generating printing data defining information relating to the dot formation contents of the nozzle corresponding to the third image data;
And a printing step of printing the image on the medium by the print head based on the printing data. Printing data for generating printing data used in a printing apparatus that prints an image on the medium by a print head having a nozzle capable of forming two or more types of dots of different sizes on the medium used for printing A generating device,
First image data acquisition means for acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Nozzle information storage means for storing nozzle information indicating the characteristics of the nozzle;
Nozzle use information setting means for setting whether or not to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on the nozzle information;
In the first image data, the pixel value of the pixel data set as non-use by the nozzle use information setting unit is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. Second image data generating means for generating second image data distributed to the pixel values of the unprocessed pixels,
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of the pixel data in the second image data into an N (M> N ≧ 2) value. N-value conversion processing means for
A printing data generation device, comprising: printing data generation means for generating printing data defining information relating to dot formation contents of the nozzle corresponding to the third image data. Used to generate printing data used in a printing apparatus that prints an image on the medium by a print head having nozzles capable of forming two or more types of dots of different sizes on the medium used for printing. A data generation program for printing
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
A nozzle use information setting step for setting whether to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on nozzle information indicating the characteristics of the nozzle;
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
Including a program used for causing a computer to execute processing including a printing data generation step for generating printing data defining information relating to dot formation contents of the nozzle corresponding to the third image data. Data generation program for printing. Printing data for generating printing data used in a printing apparatus that prints an image on the medium by a print head having a nozzle capable of forming two or more types of dots of different sizes on the medium used for printing A generation method,
A first image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
A nozzle use information setting step for setting whether to use a nozzle corresponding to each pixel data for each pixel data in the first image data based on nozzle information indicating the characteristics of the nozzle;
In the first image data, the pixel value of the pixel data set as non-use in the nozzle use information setting step is changed to the minimum density value, and the original pixel value before the change is positioned in the vicinity of the pixel value. A second image data generation step for generating second image data distributed to the pixel values of the unprocessed pixels;
The third image data is generated by performing an N-value conversion process, which is a process of converting a pixel value of M (M ≧ 3) value of pixel data in the second image data into an N (M> N ≧ 2) value. N-value processing step to perform,
And a print data generation step for generating print data defining information relating to dot formation contents of the nozzle corresponding to the third image data. Image data having a print head having nozzles capable of forming two or more types of dots of different sizes for printing and corrected using pixel values of pixel data set to disable the nozzles A nozzle setting information table generating method for generating a nozzle setting information table used in a printing apparatus for printing an image on the medium based on printing data generated from
An image data acquisition step of acquiring first image data having a plurality of pixel data corresponding to pixel values of M (M ≧ 3) values;
Nozzle use information setting for setting whether to use a nozzle corresponding to each pixel data for each pixel data of the image data acquired in the image data acquisition step based on nozzle information indicating the characteristics of the nozzle Steps,
Nozzle setting for generating a nozzle setting information table in which whether or not to use a nozzle corresponding to each pixel data is set for each pixel data of the image data based on the setting information in the nozzle usage information setting step A nozzle setting information table generation method comprising: an information table generation step.

Images