JP3598674B2 - Image data binarization device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a method for obtaining color pseudo halftone image data used for recording in a color ink coating type printer of an interlace drive system by binarizing color halftone image data represented by multi-values by a dither method. UsedPictureImage data binarization equipmentIn placeRelated.
[0002]
[Prior art]
In a recording apparatus that performs recording by moving a recording head and a recording medium (recording paper or the like) relative to each other, important factors that affect recording quality are the transport accuracy of the recording medium in the sub-scanning direction and recording of the recording head. Position accuracy. In a general printing apparatus, a plurality of printing elements are arrayed in the sub-scanning direction at intervals of an integral multiple of the printing resolution, and the interval P between printing elements and the number q of printing elements (the actual Using a print head that has a relatively prime relationship with the number of used prints, and always feeds the print medium in the sub-scanning direction at a constant pitch, while using a print element in which adjacent lines are different. High accuracy is achieved by a so-called interlace drive system that operates to be recorded.
[0003]
According to such an interlaced drive type printing apparatus, there is no problem that the variation in the arrangement intervals of the printing elements does not noticeably appear in the printing quality, and the feeding amount of the printing medium is always constant, so that the transport accuracy is uneven. And high recording quality can be obtained.
[0004]
[Problems to be solved by the invention]
However, among such interlaced driving type recording apparatuses, particularly when a printer such as a color ink jet printer that records an image by applying ink is used, a general dot-dispersion type dither matrix is used. When the pseudo halftone image data obtained by binarization is printed, the following problem may occur.
[0005]
For example, the number of printing elements = 63 (actually, 63 of the number of printing elements = 64 are used), the interval P between printing elements = 2, the gradation level of the halftone image is 1 to 64, and the dot dispersion The case where the pattern dither matrix shown in FIG. 9A is used will be described. This dither matrix is formed by repeatedly arranging the basic arrangement pattern of the threshold values shown in FIG.
[0006]
Here, as a multi-valued halftone image, when an image in which all pixels are C (cyan) = 16, M (magenta) = 0, and Y (yellow) = 32 is binarized, C is on. As shown in FIG. 10, the position (the position where the ink of C is ejected) is only the odd-numbered row Od among the rows of the dither matrix.
[0007]
Further, as shown in FIG. 11, the position where Y is turned on (the position where the ink of Y is ejected) is the same as the position where C is turned on, and is also arranged on the even-numbered row Ev.
When the binarized pseudo-halftone image is printed by the interlace driving method, first, as shown in FIG. 12, odd-numbered rows are used in the first first main scan using 63 recording elements for each color. Only Od is printed. As can be seen from FIGS. 10 and 11, C and Y are recorded in the odd-numbered rows Od, so that the C and Y inks are ejected at the same ratio.
[0008]
Next, the printing head is relatively moved (sub-scanning) by 32 printing elements in the sub-scanning direction, and printing in the second main scanning is performed. In the second main scanning, only the even-numbered rows Ev are printed. In the even-numbered row Ev, only Y is on, as can be seen from FIGS. 10 and 11, so only Y is recorded.
[0009]
Next, the printing in the third main scanning is performed by moving the printing head relative to 32 printing elements in the sub-scanning direction. Since the third main scan is printing of only the odd-numbered rows Od, C and Y inks are ejected as in the first main scan.
In the next fourth main scan, ejection of only Y is performed as in the second main scan.
[0010]
In this way, an image of the same color arrangement of C (cyan) = 16, M (magenta) = 0, and Y (yellow) = 32 is printed at twice the resolution of the spacing between recording elements.
However, because of the interlace driving method, as shown in FIG. 12, in the overlapping area R1 of the printing of the first main scanning and the second main scanning, CY is jetted first and then Y is jetted. In the overlapping region R2 of the second main scan and the third main scan, Y is jetted first, and CY is jetted later. In the overlapping area R3 between the third main scanning and the fourth main scanning, CY is jetted first and Y is jetted later as in the overlapping area R1.
[0011]
Since the overlapping regions R1 to R3 are regions showing the same coloration, the same amount of ink of C and Y is ejected, but the order of ejection is different in the adjacent overlapping regions R1 to R3 as described above. The ink applied to the even-numbered row Ev and the ink applied to the odd-numbered row Od are not completely independent from each other, and there are overlapping portions in adjacent portions of each other. If the overlapping order of the inks is reversed due to the difference in the ejection order in this part, the delicate difference in the ink properties such as the degree of bleeding causes a delicate difference in color. For this reason, there is a problem that the overlapping regions R1, R2, and R3 appear as a stripe pattern even though they are the same color arrangement region as the halftone image.
[0012]
An object of the present invention is to prevent a phenomenon in which a stripe pattern occurs in such an interlaced drive recording despite the same color arrangement area.
[0013]
Means for Solving the Problems and Effects of the Invention
Here, one or more inventions are described and have the structure and features described below.
Of the present inventionImage data binarization deviceIsImage data storage means for storing multi-valued color halftone image data, dither matrix storage means for storing a dither matrix, and color halftone image data stored in the image data storage means A binarization unit for binarizing using the dither matrix stored in the storage unit to obtain color pseudo halftone image data, wherein the nozzle interval is equivalent to P (P is an integer of 2 or more) lines. It is used for an interlaced drive type color ink coating type printer having a head.
[0014]
In the above-described conventional example, the nozzle interval P of the recording head is P = 2, and in the same color arrangement region of the color halftone image data, the color pseudo halftone image data recorded at a time in the main scanning is the same in the main scanning direction. Color is applied continuously. That is, the color pseudo halftone image data recorded in the main scanning of the recording head is a region where CY is printed at 50% or a region where Y is printed at 50%, and the same color arrangement is continuously arranged in the main scanning direction. I have. For this reason, since a subtle difference that occurs in spite of the same color arrangement area as described above exists continuously in all main scanning directions, a stripe pattern occurs.
[0015]
However, the present inventionImage data binarization deviceThe dither matrix is used to binarize color pseudo halftone image data, which is recorded at one time in the main scan, in the same color arrangement area of the color halftone image data so that the same color arrangement is not continuously recorded in the main scan direction. It is formed to be. Therefore, even if a delicate color difference occurs due to a difference in the overlapping order in the same color arrangement area, the continuity of the color arrangement in the main scanning direction is disturbed, and the delicate color difference is confused in appearance, Stripes are less noticeable. For this reason, the occurrence of a stripe pattern can be substantially prevented.
[0016]
For example, when the dither matrix is formed by the dot dispersion method, one half of the matrix in the main scanning direction of the dither matrix has an integer n rows which are relatively prime to the nozzle interval P of the recording head, and has In the same color arrangement region of the color halftone image data, the color pseudo halftone image data recorded at a time in the main scanning is continuously shifted in the main scanning direction due to the shift in the direction or the anti-sub scanning direction. It is formed so that it is binarized to a state where it is not recorded. Since the number of rows to be shifted is an integer n which is relatively prime to the nozzle interval P of the print head, the same color is arranged in the first half and the second half in the main scanning direction for each matrix in the same main scanning. Since the same color arrangement is finely disturbed, the occurrence of a stripe pattern can be substantially prevented.
[0017]
Further, when the dither matrix is formed by the dot dispersion method, the arrangement of the two thresholds in one half of the main scanning direction in the basic arrangement pattern composed of four thresholds used in the dot dispersion method is P. Similarly, by being displaced in the sub-scanning direction or the anti-sub-scanning direction by an integer n lines which are relatively prime, similarly, the color recorded at one time in the main scanning in the same color arrangement area of the color halftone image data The pseudo halftone image data is formed so as to be binarized so that the same color arrangement is not continuously recorded in the main scanning direction. That is, the set of the four thresholds is a threshold that is continuous from large to small or small to large, and half of this threshold is shifted by an integer n rows that are relatively prime to P in the main scanning direction. By disturbing the arrangement state of thresholds created by a simple dot dispersion method, color pseudo halftone image data recorded at a time in main scanning is continuously recorded with the same color in the main scanning direction. Is prevented, and the occurrence of a stripe pattern can be substantially prevented.
[0018]
The dither matrix is formed by a dot dispersion method, and the size of the dither matrix in the sub-scanning direction is set to m (m is an integer of 2 or more), and a threshold value (for example, four threshold values) used in the dot dispersion method Let k (k is an integer satisfying 1 ≦ k ≦ m−1) be the number of moving rows in the sub-scanning direction in the basic arrangement pattern consisting of By disturbing the arrangement of the threshold values created by the dispersion method, the color pseudo halftone image data recorded at a time in the main scanning is prevented from being continuously recorded with the same color arrangement in the main scanning direction. In addition, the occurrence of stripes can be substantially prevented. Note that the basic arrangement pattern is not limited to a pattern composed of four threshold values, and may be any number as long as it is 2 n (n ≧ 0).
[0019]
In addition, when the thresholds are sequentially arranged from large to small or small to large in the dither matrix, the number of continuous occurrences of odd-numbered rows or even-numbered rows is 4 or less at first, and thereafter, odd-numbered rows or even-numbered rows are reduced. Even in the case of a dither matrix in which the number of continuous appearances is 8 or less, color pseudo halftone image data recorded at one time in main scanning is disturbed by disturbing the arrangement of thresholds created by a simple dot dispersion method. The same coloration is prevented from being continuously recorded in the main scanning direction, and the occurrence of a stripe pattern can be substantially prevented.
[0020]
When P = 2, a dither matrix may be arranged such that odd rows and even rows alternately appear in the dither matrix when thresholds are sequentially arranged from large to small or small to large. Due to the disturbance of the arrangement of the threshold values created by the simple dot dispersion method, the color pseudo halftone image data recorded at a time in the main scanning is continuously recorded in the same color in the main scanning direction. Is prevented, and the occurrence of a striped pattern can be substantially prevented.
[0021]
Further, as described below, a dither matrix having a mechanism for preventing occurrence of a stripe pattern different from the above-described mechanism may be employed. That is, the present inventionImage data binarization deviceThe dither matrix is obtained by dithering color pseudo halftone image data used for recording in an interlace drive type color ink coating type printer in which a nozzle interval of a recording head is equivalent to P (P is an integer of 2 or more) lines. A dither matrix used for binarizing and obtaining color halftone image data represented by multi-values,
In the same color arrangement area, P sets of color pseudo halftone image data, which is one set of color pseudo halftone image data printed by the main scan of the print head every P scan, are binary-coded to similar color schemes. It is characterized in that it is formed to be
[0022]
Since the difference in the overlapping order of different color arrangements causes a stripe pattern, if the overlapping color arrangements are similar to each other, the above-described mechanism of the occurrence of the stripe pattern itself does not occur, so that the occurrence of the stripe pattern can be prevented. it can.
For example, assuming that the size of the dither matrix in the sub-scanning direction is m (m is an integer of 2 or more), if m and P are dither matrices that are relatively prime, a color pseudo halftone image recorded in each main scan The P sets on which the data are superimposed are similar to each other. Therefore, no matter what order the overlapping order is, since the colors are similar, no color difference occurs and the stripe pattern itself does not occur.
[0023]
For this reason, using the various dither matrices described above, the color halftone image data represented by multi-values is binarized into color pseudo halftone image data, and the color pseudo halftone image data is stored in the nozzles of the recording head. If printing is performed by an interlace driving type color ink coating type printer in which the interval is equivalent to P (P is an integer of 2 or more) lines, the interlacing driving type color ink coating can be performed without generating a stripe pattern that does not actually exist. Pseudo-halftone images can be recorded on a portable printer.
[0024]
Further, the following dither matrix may be employed as follows. That is, the dither matrix in the image data binarization device of the present invention is such that when the thresholds constituting the dither matrix are sequentially arranged from large to small or small to large, P is an integer n rows that are relatively prime to P, They are sequentially arranged so as to be separated from each other in the sub-scanning direction or the anti-sub-scanning direction.
[0025]]
[0026
BEST MODE FOR CARRYING OUT THE INVENTION
[Embodiment 1]
FIG. 1 shows a configuration of a dither matrix 2 according to the first embodiment. The dither matrix 2 is composed of an 8 × 8 threshold matrix created by the dot dispersion method, and is used in an interlace driving type color inkjet printer in which the nozzle interval of the print head is equivalent to P (here, P = 2) lines. It is used to obtain color pseudo halftone image data used for recording by binarizing color halftone image data represented by multi-values. The halftone image processed by the dither matrix 2 has 64 tones of 1 to 64.
[0027]
The dither matrix 2 has a half matrix 2b in the main scanning direction of the conventional dither matrix formed by the dot dispersion method shown in FIG. = 1) It is shifted in the sub-scanning direction by the amount of the line. Conversely, P can be regarded as being shifted in the anti-sub-scanning direction by an integer n (n = 7) rows that are relatively prime.
[0028]
When the multi-value halftone image data is binarized by the dither method using the dither matrix 2 configured as described above, it is binarized as shown in FIG. The example of FIG. 2 uses the same data as the halftone image data used in the description of the conventional technology, and all the pixels have C (cyan) = 16, M (magenta) = 0, and Y (yellow) = 32 shows a binarized halftone image of the same color arrangement of 32.
[0029]
FIG. 2A corresponds to FIG. 10 showing the binarized data for C. As shown in FIG. 2A, the position where C is on is the left half of the row of the dither matrix 2. In the right half, there is an odd row Od, but in the right half, it exists in an even row Ev. FIG. 2 (b) corresponds to FIG. 11 showing the binarized data for Y. As shown in FIG. 2 (b), the position where Y is on is indicated by C in the row of the dither matrix 2. The same position as the ON position and the even line Ev are also arranged.
[0030]
When the pseudo halftone image data obtained by binarization in this way is printed by the interlace driving method, as shown in FIG. The converted pixels are printed, but C and Y are recorded in a portion corresponding to the left half matrix 2a of the dither matrix 2, so that the C and Y inks are ejected at the same ratio. However, since only Y is recorded in the portion corresponding to the right half matrix 2b of the dither matrix 2, only the Y ink is ejected. That is, in one main scan, the portion where CY is ejected and the portion where only Y is ejected are alternately arranged.
[0031]
In the second main scan, the binarized pixels are printed on the even-numbered rows Ev of the dither matrix 2, but only the Y corresponding to the left half matrix 2a of the dither matrix 2 is recorded. Is ejected. However, since C and Y are recorded in a portion corresponding to the right half matrix 2b of the dither matrix 2, the C and Y inks are ejected at the same ratio. That is, in one main scan, a portion where only Y is ejected and a portion where CY is ejected are alternately arranged.
[0032]
Thereafter, the odd-numbered main scan has the same ejection as the first main scan, and the even-numbered main scan has the same ejection as the second main scan.
In this way, an image of C (cyan) = 16, M (magenta) = 0, and Y (yellow) = 32 is recorded at a resolution twice as large as the interval between the recording elements.
[0033]
Because of the interlace driving method, as shown in FIG. 3, the overlapping area S1 of the printing of the first main scanning and the second main scanning is an overlapping state in which CY is jetted first and then Y is jetted later. And the overlapping state in which Y is injected first and CY is injected later is repeated. Further, in an overlapping area S2 between the second main scanning and the third main scanning, an overlapping state in which Y is jetted first and then CY is jetted, and a CY is jetted first and then Y is jetted later. The overlapping state is repeated. In the subsequent overlapping states, the above-mentioned states appear alternately.
[0034]
Therefore, as in the related art, in the overlapping region R1 of the first main scanning and the second main scanning, CY is first jetted first, then Y is jetted later, and the second main scanning and the third main scanning are performed. In the overlapping region R2, unlike the overlapping state in which Y is jetted first and the CY is jetted later, the overlapping state changes in the main scanning direction in each of the overlapping regions S1, S2, S3,. are doing. For this reason, the difference in coloring due to the difference in the overlapping order is mixed and inconspicuous, and the occurrence of a stripe pattern can be substantially prevented.
[0035]
[Embodiment 2]
FIG. 4 shows a configuration of a dither matrix 10 according to the second embodiment. The dither matrix 10 is composed of a 16 × 16 threshold matrix created by the dot dispersion method, and is an interlace driving type color ink coating type printer in which the nozzle interval of the recording head is equivalent to P (here, P = 2) lines. Is used to obtain the color pseudo halftone image data used for recording by binarizing the color halftone image data represented by multi-values. The halftone image processed by the dither matrix 10 has 256 tones of 1 to 256.
[0036]
The present dither matrix 10 has a special feature in the dot dispersion method. In other words, in the normal dot dispersion method, as shown in FIG. 9B, a square vertex whose sides are parallel to either the main scanning direction or the sub-scanning direction from the reference position (here, the position of “1”) (Here, “2”, “3”, “4”) are sequentially increased by half the vertical or horizontal size of the dither matrix to be created. Are repeatedly arranged while sequentially increasing the values of 5 to 8, 9 to 12,... To create a dither matrix.
[0037]
The basic arrangement pattern in the present dither matrix 10 is as shown in FIG. That is, in the normal basic arrangement pattern shown in FIG. 5A, the thresholds “2” and “4” of either half in the main scanning direction and the right half in the case of FIG. It is shifted in the sub-scanning direction by an integer n (here, “1”) rows that are relatively prime.
[0038]
The dither matrix 10 is formed by arranging the shifted basic arrangement patterns while sequentially increasing the threshold value.
When the multi-value halftone image data is binarized by the dither method using the dither matrix 10 configured as described above, the binarization is performed as shown in FIGS. The examples of FIGS. 6 and 7 show binarized halftone images of the same color arrangement in which all pixels are C (cyan) = 64, M (magenta) = 0, and Y (yellow) = 128. .
[0039]
FIG. 6 corresponds to FIG. 10 showing the binarized data for C. As shown in FIG. 6, the position where C is on is evenly located in the odd row Od and the even row Ev in the dither matrix 10. Are distributed.
FIG. 7 corresponds to FIG. 11 showing the binarized data for Y. As shown in FIG. 7, the position where Y is on is the same as the position where C is on in the dither matrix 10. In addition, it is evenly distributed in the odd rows Od and the even rows Ev.
[0040]
As described above, since the arrangement of the thresholds is disturbed from the arrangement of the thresholds created by the simple dot dispersion method, when printing by the interlace driving method, the color pseudo halftone image data recorded at one time in the main scan However, since the same coloration is prevented from being continuously recorded in the main scanning direction, the same color tone is exhibited in all the overlapping areas regardless of the order of the overlapping of the main scanning, and the stripe pattern is not generated. Absent.
[0041]
From another point of view, the fact that the same color arrangement is continuously recorded in the main scanning direction is finely disturbed, and as a result, all the main scans have almost the same color arrangement, so that a stripe pattern occurs. It can be said that the mechanism is less likely to occur, and the problem is eliminated in any order of the overlapping order.
[0042]
Although the basic arrangement pattern shown in FIG. 5B is used, a similar effect can be obtained by using FIG. 5C in which the right half is shifted in the anti-sub-scanning direction as the basic arrangement pattern.
[Embodiment 3]
The dither matrix according to the third embodiment is formed by a dot dispersion method so as to satisfy the following conditions. That is, the size of the dither matrix in the sub-scanning direction is m (m is an integer of 2 or more), and the number of moving rows in the sub-scanning direction in the basic arrangement pattern including four thresholds used in the dot dispersion method is k (k is 1 ≦ k ≦ m−1), k and m / P are relatively prime. The number k of rows moved in the sub-scanning direction corresponds to the length of the side in the sub-scanning direction in the above-described basic arrangement pattern shown in FIG.
[0043]
Specifically, if P = 2 and m = 8, m / P = 4, and integers satisfying 1 ≦ k ≦ m−1 which are relatively prime to this value “4” are 1, 3, 5, 7, and one or more of these are set as k. That is, when the basic arrangement pattern cannot be arranged with the same value of k, the basic arrangement pattern is arranged with the length of the side changed.
[0044]
Thus, in the case of P = 2, as shown in FIG. 9A, it is prevented that all of the thresholds “1 to 16” of 閾 値 of all thresholds from the smaller one are arranged in the odd-numbered row Od. You. For example, in order of the threshold value, odd-numbered rows Od, even-numbered rows Ev, even-numbered rows Ev, odd-numbered rows Od, odd-numbered rows Od, even-numbered rows Ev, even-numbered rows Ev, odd-numbered rows Od,... Since the colors are almost the same, a mechanism of generating a stripe pattern is less likely to occur. Therefore, it is possible to prevent the occurrence of the stripe pattern in any order of the main scanning.
[0045]
[Embodiment 4]
The dither matrix according to the fourth embodiment is formed by a dot dispersion method so as to satisfy the following condition. That is, assuming that the size of the dither matrix in the sub-scanning direction is m (m is an integer of 2 or more), m and P are relatively prime.
[0046]
Specifically, if P = 3, m which is relatively prime to P is 2, 4, 5, 7, 8, 10, 11, 13, 14, 16, 17, 19, 20,. . For example, when m = 8, as shown in FIG. 8, a [multiple of 3] line, a [multiple of 3 + 1] line, and a [multiple of 3 + 2] line are printed for each main scan. Pseudo halftone image data printed in one main scan is obtained by being processed by a plurality of dither matrices in the sub-scanning direction. In each of the plurality of dither matrices, Rather than matching any one of the [multiple of 3] row, [multiple of 3 + 1] row, and [multiple of 3 + 2] row of the matrix, P and m are relatively prime. Therefore, the line recorded in one main scan may match the [multiple of 3] line, the [multiple of 3 + 1] line, or the [multiple of 3 + 2] line depending on the dither matrix. It may be the same and not constant.
[0047]
When this is viewed from the dither matrix side, pixels binarized in a specific row of the dither matrix are printed in the [multiple of 3] th main scan, [multiple of 3 + 1] or [multiple of 3] +2] th main scan.
For this reason, the color pseudo halftone image data recorded at one time in the main scanning is prevented from being recorded in the same color continuously in the main scanning direction, and the color arrangement state becomes substantially equal in each main scanning. . Therefore, regardless of the order of the overlapping of the main scans, the same color tone is exhibited in all the overlapping areas, and the stripe pattern does not occur.
[0048]
[Others]
In Embodiment 1, the right half matrix 2b in FIG. 1 is shifted, but the left half matrix 2a may be shifted.
When P = 2, when the dither matrix is created by determining and arranging the threshold on the dither matrix from large to small or from small to large, the position of the dither matrix in the main scanning direction is randomly determined. However, the position in the sub-scanning direction may be determined such that the threshold value is alternately arranged in odd rows and even rows from small to large or large to small. This prevents the color pseudo halftone image data recorded at one time in the main scan from being recorded in the same color continuously in the main scan direction. Therefore, regardless of the order in which the main scans overlap, the same color tone is exhibited in all the overlapping areas, and a stripe pattern does not occur.
[0049]
In addition, in order to substantially prevent the occurrence of a stripe pattern, the arrangement of the threshold values for the odd-numbered rows and the even-numbered rows is based on the arrangement of the threshold values sequentially from large to small or small to large. Preferably, the dither matrix has a continuous appearance number of 4 or less, and thereafter, an odd row or even row has a continuous appearance number of 8 or less.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of a dither matrix according to a first embodiment of the present invention.
FIG. 2 is an explanatory diagram of an arrangement for each color turned on by binarization according to the first embodiment;
FIG. 3 is an explanatory diagram of an overlapping state of each main scan.
FIG. 4 is a diagram illustrating a configuration of a dither matrix according to a second embodiment;
FIG. 5 is an explanatory diagram of a configuration of a basic arrangement pattern of thresholds used in a second embodiment.
FIG. 6 is an explanatory diagram of an arrangement which is turned on by binarization according to the second embodiment.
FIG. 7 is an explanatory diagram of an arrangement which is turned on by binarization according to the second embodiment;
FIG. 8 is an explanatory diagram of an arrangement state of thresholds according to the fourth embodiment.
FIG. 9 is an explanatory diagram of a conventional dither matrix and a basic arrangement pattern.
FIG. 10 is an explanatory diagram of a binarized state using a conventional dither matrix.
FIG. 11 is an explanatory diagram of a binarized state using a conventional dither matrix.
FIG. 12 is an explanatory diagram of a conventional overlapping state of each main scan.
[Explanation of symbols]
2: Dither matrix 2a: Left half matrix
2b: right half matrix 10: dither matrix
Ev: Even row Od: Odd row S1, S2, S3: Overlap area

Claims (8)

Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
  An image data binarization apparatus used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
  The dither matrix is formed by a dot dispersion method, and one half of the matrix in the main scanning direction of the dither matrix is an integer n rows which are relatively prime to P, in the sub-scanning direction or in the anti-sub-scanning direction. Staggered
  An image data binarization device, characterized in that: Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
  An image data binarization apparatus used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
  The dither matrix is formed by the dot dispersion method, and the arrangement of two thresholds in the half in the main scanning direction in the basic arrangement pattern composed of four thresholds used in the dot dispersion method is different from P. Are shifted in the sub-scanning direction or the anti-sub-scanning direction by an integer n lines
  An image data binarization device, characterized in that: Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
  An image data binarization apparatus used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
  The dither matrix is formed by a dot dispersion method, and the size of the dither matrix in the sub-scanning direction is set to m (m is an integer of 2 or more). Assuming that the number of rows moved in the scanning direction is k (k is an integer satisfying 1 ≦ k ≦ m−1), k and m / P are relatively prime.
  An image data binarization device, characterized in that: Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
  An image data binarization apparatus used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
  The dither matrix is used to sequentially arrange thresholds from large to small or small to large. At first, the number of continuous occurrences of odd or even lines is 4 or less, and thereafter, the number of continuous occurrences of odd or even lines is 8 or less.
  An image data binarization device, characterized in that: Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
  An image data binarization apparatus used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
  P = 2, and the dither matrix is arranged so that odd-numbered rows and even-numbered rows alternately appear when thresholds are sequentially arranged from large to small or small to large.
  An image data binarization device, characterized in that: Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
  An image data binarization apparatus used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
  In the dither matrix, in the same color arrangement area, P sets of color pseudo-halftone image data, which is a set of color pseudo-halftone image data printed by the main scan of the print head for each P scan, are similar to each other. It is formed so that it is binarized in the color scheme of
  An image data binarization device, characterized in that: Assuming that the size of the dither matrix in the sub-scanning direction is m (m is an integer of 2 or more), m and P are relatively prime.
  7. The image data binarization device according to claim 6, wherein: Image data storage means for storing color halftone image data represented by multi-values,
  Dither matrix storage means for storing a dither matrix;
  Binarizing means for binarizing the color halftone image data stored in the image data storage means using a dither matrix stored in the dither matrix storage means to obtain color pseudo halftone image data; With
An image data binarization device used in an interlaced drive type color ink coating type printer having a recording head whose nozzle interval is equivalent to P (P is an integer of 2 or more) lines,
In the dither matrix, when the thresholds forming the dither matrix are sequentially arranged from large to small or small to large, P is an integer n rows that are relatively prime to each other, and are separated in the sub-scanning direction or the anti-sub-scanning direction. It is arranged sequentially so that it becomes a state
  An image data binarization device, characterized in that:

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