JP2008035379A - Printing apparatus, printing program, printing method, image processing apparatus, image processing program and image processing method, display apparatus, display program and display method, and storage medium storing the program - Google Patents

Abstract

Provided are a printing apparatus, an image processing apparatus, and a display apparatus that are suitable for efficiently using a common dither matrix stored in a memory when converting N-valued image data.
An image data acquisition unit that acquires M-value image data, and N-value conversion processing that uses resolution conversion, color conversion, and a dither method for the acquired image data. An image processing unit 11 that performs various image processing to convert M-value image data into N-value image data, a print data generation unit 12 that generates print data based on the converted image data, and printing based on the print data The configuration includes a printing unit 13 that executes processing. Further, the reference dither data is divided into a plurality of threshold sets, which are sequentially stored in a storage area having consecutive memory addresses. The threshold set stored in this way is cyclically and repeatedly read out from the successive addresses, and N-value conversion processing is performed on the image data of each color.
[Selection] Figure 1

Description

  The present invention stores a printing apparatus, a printing program, a printing method, an image processing apparatus, an image processing program and an image processing method, a display apparatus, a display program and a display method, and the program that are suitable for image processing using a dither method. The present invention relates to a storage medium.

Conventionally, as a technique for performing N-value (multi-value) of image data using a dither matrix, for example, there are an image processing apparatus described in Patent Document 1 and an image forming apparatus described in Patent Document 2.
The image processing apparatus of Patent Document 1 performs N-value conversion (multi-value conversion) on image data by arranging dither matrices in a staircase pattern. Specifically, the dither matrix is arranged while sequentially shifting in the main scanning direction or the sub-scanning direction. In other words, if a common (same content) dither matrix smaller than the image data size is regularly arranged in a grid pattern with respect to the image data, the dot formation pattern becomes regular and the image quality deteriorates. End up. Therefore, as described above, the dither matrix is shifted in a stepwise manner with respect to the image data, thereby eliminating regularity and preventing deterioration in image quality.

  The image forming apparatus disclosed in Patent Document 2 is a full-color printer that sequentially forms images in the order of Y, M, C, and K. After the black toner image is formed, the developing sleeve of the black toner developer is continuously rotated. In other words, in the image formation process, the dither matrix threshold is rotated and used for each frame, so that processing is performed using a different threshold for each color, and a common (same content) dither matrix is effectively used. Use. Thereby, generation | occurrence | production of a ghost can fully be suppressed and rotation of an excessive developing sleeve can be prevented.

Conventionally, when N-value (multi-value) is performed using a common dither matrix, only one dither matrix is read into a work memory, and this memory is repeated as many times as necessary for N-value conversion. By reading and using, the amount of memory used for the dither matrix is reduced.
In addition, when a threshold is selected using a common dither matrix stored in the memory while shifting the selection start position of the threshold, when the threshold at the beginning of a row or column in the matrix is the start position, the threshold When the selected position of the matrix reaches the final threshold of the last row or column of the matrix, the next is a cyclic transition from the last row or column of the matrix to the first row or column, The threshold values are selected in order from the first threshold value to the last threshold value of the previous row or column in the middle row or column.
JP 2000-101837 A JP 2000-29314 A

However, in the conventional techniques such as Patent Document 1 and Patent Document 2 described above, when N-value conversion is performed, the storage configuration of dither matrix data in the memory and the threshold data are read from the memory storing the dither matrix. There are no particular points regarding the memory access method.
Further, as described above, when N-value conversion is performed while shifting the selection start position of the threshold value of the common dither matrix for each color of the image data, when the common dither matrix is simply stored in the memory in the arrangement order, For each color of the image data, it is necessary to separately read out the threshold value data at the address position corresponding to the shift amount from the memory. For this reason, as the number of colors of image data increases, the number of times the threshold is read out increases, and the access time to the memory increases, which may become a bottleneck for the entire process.

  Therefore, the present invention has been made paying attention to such an unsolved problem of the conventional technology, and when converting the image data into N-values, the common dither matrix stored in the memory is efficiently used. A printing apparatus, a printing program, a printing method, an image processing apparatus, an image processing program and an image processing method, a display apparatus, a display program and a display method, and a storage medium storing the program are provided. It is aimed.

[Mode 1] In order to achieve the above object, a printing apparatus according to mode 1 includes:
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. A reference dither matrix, and the selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be a position different from the other colors, respectively. The predetermined threshold value is cyclically selected with respect to the reference dither matrix sequentially from the selection start position of each color in the reference dither matrix in the row direction or the column direction, and the selected threshold value and the corresponding pixel value or The M value pixel is determined by sequentially determining whether the dot is on or off according to the magnitude relationship with the value calculated based on the pixel value. The image data composed into a composed image data from the pixel value of the N (M> N ≧ 2) values, a printing apparatus that performs printing based on the image data after the conversion from
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. Reference dither matrix storage means for storing the reference dither matrix divided into threshold sets in a storage area in which addresses are consecutive in order from the threshold set of the selection start position;
In order from the threshold set of the selection start position in the reference dither matrix stored by the reference dither matrix storage means, each threshold set is subjected to the on / off determination process for all pixel values of the image data. Threshold reading means for cyclically and repeatedly reading out the plurality of threshold sets stored in the continuous storage area of the address, as many times as necessary for
Pixel value acquisition means for acquiring pixel values of the respective colors in order from pixel values of acquisition start positions common to the respective colors in the image data;
Using each threshold value of the threshold set sequentially read by the threshold value reading unit and the pixel value of each color acquired by the pixel value acquisition unit, each threshold value and a pixel value of a color corresponding to each of these threshold values Determination processing means for sequentially performing the determination processing for each combination;
N-value conversion means for converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination processing means;
Print data generation means for generating print data based on image data composed of pixel values converted by the N-value conversion means;
Printing means for executing a printing process based on the print data generated by the print data generation means.

  With such a configuration, the reference dither matrix storage means sequentially sets the predetermined threshold value of each color to 1 from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color. The reference dither matrix divided into a plurality of threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position, with a set of thresholds included as one threshold set.

  Then, the threshold value reading means performs the on / off determination processing for each threshold value set for all pixel values of the image data in order from the threshold value set for the selection start position in the stored reference dither matrix. For the number of times necessary for the plurality of threshold sets stored in the continuous storage area of the address, and cyclically and repeatedly read out, and by the pixel value acquisition means, an acquisition start position common to each color in the image data When the pixel value of each color is acquired in order from the pixel value of each of the color values, the determination processing unit is configured to read each threshold value of the threshold set sequentially read by the threshold value reading unit and each pixel value of the color acquired by the pixel value acquisition unit. The determination processing is sequentially performed on each combination of the threshold values and pixel values of colors corresponding to the threshold values.

Further, the N-value conversion unit converts the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing unit, and the print data generation unit converts the pixel value after conversion by the N-value conversion unit. Print data is generated based on image data composed of pixel values.
The printing unit executes a printing process based on the print data generated by the print data generation unit.

  That is, the threshold selection start position for each color is shifted in units of predetermined rows or predetermined columns of the reference dither matrix, and the thresholds are selected sequentially and cyclically from these start positions. The threshold value from the position to the position immediately before the start position of another color is also used for pixel values other than this color. Accordingly, a threshold set including one threshold value for each color is commonly used for pixel values of all colors, although the positions of pixel values to be processed are different. In addition, the reference dither matrix is stored in the storage area of consecutive addresses for each threshold set, and each threshold set is read cyclically and repeatedly, so that the reading position (pointer) is set to a predetermined amount. It is possible to read out the threshold set continuously only by shifting each pixel and to read out the corresponding threshold value for each color pixel value at a time. The effect of being able to be obtained. In addition, by reading out the threshold set in such an order, the threshold included in the threshold set can be applied to any one of the pixel values of each color acquired in order from the common start position. By repeatedly and repeatedly reading out the same threshold set, the above determination process can be performed on all the pixel values of the image data. In addition, since only one reference dither matrix needs to be stored, the memory capacity for storing the dither matrix can be reduced.

  Here, the “dither matrix” is used in N-value processing (also referred to as multi-value processing or halftone processing) using a known dither method, and predetermined threshold values are arranged in a two-dimensional matrix. It has a configuration. Similarly, each pixel value of the image data having a configuration in which pixel values are arranged in a two-dimensional matrix is associated with each threshold value of the dither matrix, and the pixel value at each corresponding position is compared with the threshold value. Then, the dot on / off state for the pixel value is determined. The size of the dither matrix is generally smaller than the matrix size of the image data, and the determination process is executed while shifting the dither matrix in the row direction and the column direction in accordance with the size of the image data. A form relating to a printing program, a form relating to a printing method, a form relating to an image processing apparatus, a form relating to an image processing program, a form relating to an image processing method, a form relating to a display apparatus, a form relating to a display program, a form relating to a display method, and storing the program The same applies to the form relating to the computer-readable storage medium, the best mode for carrying out the invention, and the like.

  In addition, the above-mentioned “cyclically select a threshold value” means, for example, that the start position of the reference dither matrix is not the top position (for example, upper left) of the matrix but the middle row or column position. After selecting the threshold value in order from the middle position to the final position of the matrix (for example, lower right), next, the selection position is changed to the head of the matrix, and then the threshold value is selected in order from the middle position to just before the middle position. For example, when there is a reference dither matrix of 8 rows × 8 columns and the start position is shifted in units of 2 rows for four colors of Cy (cyan), Mg (magenta), Ye (yellow), and Bk (black), For example, Cy is the top of the first row, Mg is the top of the third row, Ye is the top of the fifth row, and Bk is the top of the seventh row. When the selection is made cyclically, the configuration of the dither matrix for Cy is the reference dither matrix itself. Similarly, the configuration of the dither matrix for Mg is from the first row to the sixth row, from the third row to the eighth row of the reference dither matrix, and from the seventh row to the eighth row, the 1st row of the reference dither matrix. From line 2 to line 2. Similarly, in the dither matrix configuration for Ye, the first to fourth lines are the fifth to eighth lines of the reference dither matrix, and the fifth to eighth lines are 1 of the reference dither matrix. From line 4 to line 4. Similarly, in the configuration of the dither matrix for Bk, the first to second rows are the seventh to eighth rows of the reference dither matrix, and the third to eighth rows are 1 of the reference dither matrix. From line 6 to line 6. Further, although the CMYK color space has been described as an example, the same applies to other known color spaces such as CMY, CMK, RGB, RGBA, sRGB, YIQ, and YCbCr / YPbPr. A form relating to a printing program, a form relating to a printing method, a form relating to an image processing apparatus, a form relating to an image processing program, a form relating to an image processing method, a form relating to a display apparatus, a form relating to a display program, a form relating to a display method, and storing the program The same applies to the form relating to the computer-readable storage medium, the best mode for carrying out the invention, and the like.

  In addition, for example, there is a reference dither matrix of 8 rows × 8 columns, and the start position is shifted in units of 2 rows with respect to four colors of Cy (cyan), Mg (magenta), Ye (yellow), and Bk (black). To do. Here, the number of rows is i (i ≧ 1), the number of columns is j (j ≧ 1), each threshold is expressed as a ij, and the selection start positions of the colors are Cy: a11, Mg: a31, Ye, respectively. : A51 and Bk: a71. Under such conditions, the “threshold set” is (a11, a31, a51, a71), (a12, a32, a52, a72),..., (A27, a47, a67, a87), (a28, a48, a68, a88). These threshold sets are stored in this order in a storage area with consecutive addresses. That is, threshold values are selected one by one from the reference dither matrix in order from the selection start position of each color in the row direction or column direction, and a set of threshold values for each color selected one by one is set as one threshold set. In the reference dither matrix of 8 rows × 8 columns, when the number of colors of image data to be processed is 4, 16 threshold sets are formed. A form relating to a printing program, a form relating to a printing method, a form relating to an image processing apparatus, a form relating to an image processing program, a form relating to an image processing method, a form relating to a display apparatus, a form relating to a display program, a form relating to a display method, and storing the program The same applies to the form relating to the computer-readable storage medium, the best mode for carrying out the invention, and the like.

  In addition, the above-mentioned “cyclically and repeatedly read” means that the threshold sets stored in consecutive addresses are read in the order of addresses, the threshold set of the last address area is read, and then the head address is returned again. It includes repeatedly reading the threshold set in order from the address. It also includes repeatedly reading out the same threshold set (including a predetermined number of consecutive threshold sets) a predetermined number of times in the order of addresses. For example, the threshold set stored at the first and second addresses is repeatedly returned (circulated) to 1, 2, 1, 2, 1, 2,. Applicable when reading. A form relating to a printing program, a form relating to a printing method, a form relating to an image processing apparatus, a form relating to an image processing program, a form relating to an image processing method, a form relating to a display apparatus, a form relating to a display program, a form relating to a display method, and storing the program The same applies to the form relating to the computer-readable storage medium, the best mode for carrying out the invention, and the like.

[Mode 2] Further, the printing apparatus of mode 2 is the printing apparatus of mode 1,
The determination processing means uses the same number of determination processing units for each color as the number of colors of the image data to perform the determination processing, and each threshold value of the threshold set read by the threshold value reading means for each color determination process. And a threshold distribution unit that distributes to the corresponding color determination processing unit, and using the determination processing unit for each color, the determination processing for the pixel value of each color is executed in parallel. And

With such a configuration, each threshold set is read by the threshold reading unit, and when the pixel value is acquired by the pixel value acquiring unit, the determination processing unit uses the threshold distribution unit to execute each of the threshold sets. The threshold values are assigned to the determination processing units that perform the determination processing on the pixel values of the color to be processed, and the determination processing corresponding to each color executes the determination processing in parallel.
Therefore, without changing the reading order of each threshold set, the thresholds included in the threshold set read in order can be distributed to appropriate determination processing units, and the determination processing can be executed in parallel. The effect that the determination process can be performed at a higher speed is obtained.

[Mode 3] Furthermore, the printing apparatus of mode 3 is the printing apparatus of mode 2,
The determination processing in the determination processing means is performed for each row or column of each color of the image data.
With such a configuration, when the matrix size of the image data is larger than the dither matrix size, the same threshold set is repeatedly used for each row or each column, so that high-speed readout is possible. It is possible to store the threshold set in a simple cache memory, a high-speed built-in memory, etc., and the effect that the determination process can be executed easily and at a higher speed can be obtained.

[Form 4] Furthermore, the printing apparatus of form 4 is the printing apparatus of any one of forms 1 to 3,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.

  With such a configuration, when the number of rows or columns of the dither matrix is divisible by the number of colors, the amount of shift can be made equal, so the reference dither matrix can be neatly divided into a plurality of threshold sets. As a result, a threshold set having a uniform data size can be stored in the storage area of successive addresses, and the effect that the threshold set reading process can be performed more efficiently is obtained.

[Mode 5] Further, the printing apparatus of mode 5 is the printing apparatus of any one of modes 1 to 4,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets.
With such a configuration, since a predetermined number (for example, one) of threshold sets is stored in a storage area of one address, a predetermined number (for example, one) of threshold sets is read in one access. As a result, the threshold value set can be read more efficiently.

[Mode 6] On the other hand, in order to achieve the above object, the printing program of mode 6
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from the pixel value of N ≧ 2) values, there printing program for printing processing based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A determination process step of sequentially performing the determination process on the pixel value using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color corresponding to the threshold value;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A print data generation step for generating print data based on the image data composed of the pixel values converted in the N-value conversion step;
A program used for causing a computer to execute a process including a print step for executing a print process based on the print data generated in the print data generation step is included.

  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 the first aspect can be obtained.

[Mode 7] Further, the printing program of mode 7 is the printing program of mode 6,
In the determination processing step, each threshold value of the threshold set read in the threshold value reading step is equal to the number of colors of the image data, and the corresponding color determination is performed in the determination processing unit for each color performing the determination processing. It distributes to a processing unit, and causes the plurality of determination processing units to execute the determination processing on the pixel values of the respective colors in parallel.
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 according to the second aspect are obtained.

[Embodiment 8] Further, the printing program of Embodiment 8 is the printing program of Embodiment 7,
The determination processing in the determination processing step is performed for each row or column of each color of the image data.
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 the third aspect can be obtained.

[Mode 9] Furthermore, the printing program of mode 9 is the printing program of any one of modes 6 to 8,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
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 the fourth aspect are obtained.

[Mode 10] Furthermore, the printing program of mode 10 is the printing program of any one of modes 6 to 9,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets. To do.
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 the fifth aspect are obtained.

[Mode 11] On the other hand, in order to achieve the above object, a computer-readable storage medium according to mode 10 is provided.
A computer-readable storage medium storing the printing program according to any one of Embodiments 6 to 10.
As a result, the printing program according to any one of Embodiments 6 to 10 is transmitted to a user such as a user via a computer-readable storage medium such as a CD-ROM, DVD-ROM, FD, or semiconductor chip. It can be provided easily and reliably.

[Mode 12] On the other hand, in order to achieve the above object, the printing method of mode 12 includes:
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from N ≧ 2) of pixel values, there printing method for printing based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A determination process step of sequentially performing the determination process on the pixel value using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color corresponding to the threshold value;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A print data generation step for generating print data based on the image data composed of the pixel values converted in the N-value conversion step;
And a printing step for executing a printing process based on the printing data generated in the printing data generation step.
Thereby, the same operation and effect as those of the printing apparatus of aspect 1 can be obtained.

[Mode 13] Furthermore, the printing method of mode 13 is the printing method of mode 12,
In the determination processing step, each threshold value of the threshold set read in the threshold value reading step is equal to the number of colors of the image data, and the corresponding color determination is performed in the determination processing unit for each color performing the determination processing. It distributes to a processing unit, and causes the plurality of determination processing units to execute the determination processing on the pixel values of the respective colors in parallel.
Thereby, an operation and effect equivalent to that of the printing apparatus of mode 2 can be obtained.

[Form 14] Furthermore, the printing method of form 14 is the printing method of form 13,
The determination processing in the determination processing step is performed for each row or column of each color of the image data.
Thereby, the same operation and effect as those of the printing apparatus of mode 3 can be obtained.

[Form 15] Furthermore, the printing method of form 15 is the printing method of any one of forms 12 to 14,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
Thereby, the same operation and effect as those of the printing apparatus of aspect 4 can be obtained.

[Mode 16] Furthermore, the printing method of mode 16 is the printing method of any one of modes 12 to 15,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets. To do.
Thereby, an operation and effect equivalent to that of the printing apparatus of mode 5 can be obtained.

[Mode 17] On the other hand, in order to achieve the above object, an image processing apparatus according to mode 17
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. A reference dither matrix, and the selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be a position different from the other colors, respectively. The predetermined threshold value is cyclically selected with respect to the reference dither matrix sequentially from the selection start position of each color in the reference dither matrix in the row direction or the column direction, and the selected threshold value and the corresponding pixel value or The M value pixel is determined by sequentially determining whether the dot is on or off according to the magnitude relationship with the value calculated based on the pixel value. The image data composed of an image processing apparatus for converting the formed image data from the pixel value of the N (M> N ≧ 2) values from,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. Reference dither matrix storage means for storing the reference dither matrix divided into threshold sets in a storage area in which addresses are consecutive in order from the threshold set of the selection start position;
In order from the threshold set of the selection start position in the reference dither matrix stored by the reference dither matrix storage means, each threshold set is subjected to the on / off determination process for all pixel values of the image data. Threshold reading means for cyclically and repeatedly reading out the plurality of threshold sets stored in the continuous storage area of the address, as many times as necessary for
Determination processing means for sequentially performing the determination processing on the pixel value using each threshold of the threshold set sequentially read by the threshold reading means and the pixel value of each color corresponding to each threshold;
N-value conversion means for converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination processing means.

  With such a configuration, the reference dither matrix storage means sequentially sets the predetermined threshold value of each color to 1 from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color. The reference dither matrix divided into a plurality of threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position, with a set of thresholds included as one threshold set.

Then, the threshold value reading means performs the on / off determination processing for each threshold value set for all pixel values of the image data in order from the threshold value set for the selection start position in the stored reference dither matrix. For the number of times necessary for the plurality of threshold sets stored in the continuous storage area of the address, and cyclically and repeatedly read out, and by the pixel value acquisition means, an acquisition start position common to each color in the image data When the pixel value of each color is acquired in order from the pixel value of each of the color values, the determination processing unit is configured to read each threshold value of the threshold set sequentially read by the threshold value reading unit and each pixel value of the color acquired by the pixel value acquisition unit. The determination processing is sequentially performed on each combination of the threshold values and the pixel values of the colors corresponding to the threshold values.
Further, the N-value conversion unit converts the pixel value of each color into any of N types of numerical values based on the determination result of the determination processing unit.
As a result, the same operations and effects as those of the printing apparatus according to mode 1 can be obtained.

[Mode 18] Further, an image processing apparatus of mode 18 is the image processing apparatus of mode 17,
The determination processing means uses the same number of determination processing units for each color as the number of colors of the image data to perform the determination processing, and each threshold value of the threshold set read by the threshold value reading means for each color determination process. And a threshold distribution unit that distributes to the corresponding color determination processing unit, and using the determination processing unit for each color, the determination processing for the pixel value of each color is executed in parallel. And
As a result, the same operations and effects as those of the printing apparatus of aspect 2 can be obtained.

[Mode 19] Furthermore, an image processing apparatus according to mode 19 is the image processing apparatus according to mode 18,
The determination processing in the determination processing means is performed for each row or column of each color of the image data.
As a result, the same operations and effects as those of the printing apparatus of aspect 3 can be obtained.

[Mode 20] Furthermore, the image processing apparatus according to mode 20 is the image processing apparatus according to any one of modes 17 to 19,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
Thereby, the same operation and effect as those of the printing apparatus of aspect 4 can be obtained.

[Mode 21] Furthermore, the image processing apparatus according to mode 21 is the image processing apparatus according to any one of modes 17 to 20,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets.
As a result, the same operations and effects as those of the printing apparatus according to mode 5 can be obtained.

[Mode 22] On the other hand, in order to achieve the above object, an image processing program of mode 22
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M There the image processing program to be converted in the composed image data from the pixel value of N ≧ 2) values,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A determination process step of sequentially performing the determination process on the pixel value using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color corresponding to the threshold value;
A program used for causing a computer to execute a process including an N-value conversion step of converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination process step, To do.

  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 image processing apparatus according to the seventeenth aspect are obtained.

[Mode 23] Further, the image processing program of mode 23 is the image processing program of mode 22,
In the determination processing step, each threshold value of the threshold set read in the threshold value reading step is equal to the number of colors of the image data, and the corresponding color determination is performed in the determination processing unit for each color performing the determination processing. It distributes to a processing unit, and causes the plurality of determination processing units to execute the determination processing on the pixel values of the respective colors in parallel.
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 image processing apparatus according to aspect 18 are obtained.

[Mode 24] Furthermore, the image processing program of mode 24 is the image processing program of mode 23,
The determination processing in the determination processing step is performed for each row or column of each color of the image data.
With such a configuration, when the program is read by the computer and the computer executes processing in accordance with the read program, operations and effects equivalent to those of the image processing apparatus according to the nineteenth aspect are obtained.

[Mode 25] Furthermore, the image processing program of mode 25 is the image processing program of any one of modes 22 to 24,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
With this 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 image processing apparatus according to the twentieth aspect are obtained.

[Mode 26] Further, the image processing program of mode 26 is the image processing program of any one of modes 22 to 25,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets. To do.
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 image processing device according to mode 21 are obtained.

[Mode 27] On the other hand, in order to achieve the above object, a computer-readable storage medium according to mode 27 is provided.
A computer-readable storage medium storing an image processing program according to any one of forms 22 to 26.
As a result, the image processing program according to any one of Embodiments 22 to 26 is sent to a user such as a user via a computer-readable storage medium such as a CD-ROM, DVD-ROM, FD, or semiconductor chip. Can be provided easily and reliably.

[Mode 28] On the other hand, in order to achieve the above object, an image processing method according to mode 28
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M There the image processing method of converting the composed image data from the pixel value of N ≧ 2) values,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A determination process step of sequentially performing the determination process on the pixel value using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color corresponding to the threshold value;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step.
Thereby, the same operation and effect as those of the image processing apparatus according to mode 17 can be obtained.

[Mode 29] Furthermore, the image processing method of mode 29 is the same as the image processing method of mode 28,
In the determination processing step, each threshold value of the threshold set read in the threshold value reading step is equal to the number of colors of the image data, and the corresponding color determination is performed in the determination processing unit for each color performing the determination processing. It distributes to a processing unit, and causes the plurality of determination processing units to execute the determination processing on the pixel values of the respective colors in parallel.
Thereby, the same operation and effect as those of the image processing device according to aspect 18 are obtained.

[Mode 30] Furthermore, the image processing method of mode 30 is the same as the image processing method of mode 29,
The determination processing in the determination processing step is performed for each row or column of each color of the image data.
Thereby, the same operation and effect as those of the image processing apparatus of mode 19 are obtained.

[Mode 31] Furthermore, the image processing method of mode 31 is the image processing method of any one of modes 27 to 30,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
Thereby, the same operation and effect as those of the image processing apparatus according to mode 20 can be obtained.

[Mode 32] Furthermore, the image processing method of mode 32 is the image processing method of any one of modes 27 to 31,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets. To do.
Thereby, the same operation and effect as those of the image processing device in mode 21 are obtained.

[Mode 33] On the other hand, in order to achieve the above object, a display device of mode 33
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. A reference dither matrix, and the selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be a position different from the other colors, respectively. The predetermined threshold value is cyclically selected with respect to the reference dither matrix sequentially from the selection start position of each color in the reference dither matrix in the row direction or the column direction, and the selected threshold value and the corresponding pixel value or The M value pixel is determined by sequentially determining whether the dot is on or off according to the magnitude relationship with the value calculated based on the pixel value. The image data composed into a composed image data from the pixel value of the N (M> N ≧ 2) values, a display device that performs display processing based on the image data after the conversion from
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. Reference dither matrix storage means for storing the reference dither matrix divided into threshold sets in a storage area in which addresses are consecutive in order from the threshold set of the selection start position;
In order from the threshold set of the selection start position in the reference dither matrix stored by the reference dither matrix storage means, each threshold set is subjected to the on / off determination process for all pixel values of the image data. Threshold reading means for cyclically and repeatedly reading out the plurality of threshold sets stored in the continuous storage area of the address, as many times as necessary for
Determination processing means for sequentially performing the determination processing on the pixel value using each threshold of the threshold set sequentially read by the threshold reading means and the pixel value of each color corresponding to each threshold;
N-value conversion means for converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination processing means;
Display data generating means for generating display data based on image data composed of pixel values converted by the N-value converting means;
Display means for executing display processing based on the display data generated by the display data generation means.

  With such a configuration, the reference dither matrix storage means sequentially sets the predetermined threshold value of each color to 1 from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color. The reference dither matrix divided into a plurality of threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position, with a set of thresholds included as one threshold set.

  Then, the threshold value reading means performs the on / off determination processing for each threshold value set for all pixel values of the image data in order from the threshold value set for the selection start position in the stored reference dither matrix. For the number of times necessary for the plurality of threshold sets stored in the continuous storage area of the address, and cyclically and repeatedly read out, and by the pixel value acquisition means, an acquisition start position common to each color in the image data When the pixel value of each color is acquired in order from the pixel value of each of the color values, the determination processing unit is configured to read each threshold value of the threshold set sequentially read by the threshold value reading unit and each pixel value of the color acquired by the pixel value acquisition unit. The determination processing is sequentially performed on each combination of the threshold values and pixel values of colors corresponding to the threshold values.

Further, the N-value conversion unit converts the pixel value of each color into one of N types based on the determination result of the determination processing unit, and the display data generation unit converts the pixel value after the conversion by the N-value conversion unit. Display data is generated based on image data composed of pixel values.
And a display means performs a display process based on the display data produced | generated by the said display data production | generation means.
Thereby, the same operation and effect as those of the printing apparatus of aspect 1 can be obtained.

[Mode 34] Furthermore, the display device of mode 34 is the display device of mode 33,
The determination processing means uses the same number of determination processing units for each color as the number of colors of the image data to perform the determination processing, and each threshold value of the threshold set read by the threshold value reading means for each color determination process. And a threshold distribution unit that distributes to the corresponding color determination processing unit, and using the determination processing unit for each color, the determination processing for the pixel value of each color is executed in parallel. And
Thereby, an operation and effect equivalent to that of the printing apparatus of mode 2 can be obtained.

[Mode 35] Furthermore, the display device of mode 35 is the display device of mode 34,
The determination processing in the determination processing means is performed for each row or column of each color of the image data.
Thereby, the same operation and effect as those of the printing apparatus of mode 3 can be obtained.

[Mode 36] Furthermore, the display device of mode 36 is the display device of any one of modes 33 to 35,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
Thereby, the same operation and effect as those of the printing apparatus of aspect 4 can be obtained.

[Mode 37] Furthermore, the display device of mode 37 is the display device of any one of modes 33 to 36.
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets.
Thereby, an operation and effect equivalent to that of the printing apparatus of mode 5 can be obtained.

[Mode 38] On the other hand, in order to achieve the above object, the display program of mode 38
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from N ≧ 2) of pixel values, there display program performs a display process based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A determination process step of sequentially performing the determination process on the pixel value using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color corresponding to the threshold value;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A display data generation step for generating display data based on the image data composed of the pixel values converted in the N-value conversion step;
A program used for causing a computer to execute a process including a display step of executing a display process based on the display data generated in the display data generation step is included.

  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 display device according to the thirty-third aspect are obtained.

[Form 39] Furthermore, the display program of form 39 is the display program of form 38,
In the determination processing step, each threshold value of the threshold set read in the threshold value reading step is equal to the number of colors of the image data, and the corresponding color determination is performed in the determination processing unit for each color performing the determination processing. It distributes to a processing unit, and causes the plurality of determination processing units to execute the determination processing on the pixel values of the respective colors in parallel.
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 display device according to the thirty-fourth aspect are obtained.

[Form 40] Furthermore, the display program of form 40 is the display program of form 39,
The determination processing in the determination processing step is performed for each row or column of each color of the image data.
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 display device according to mode 35 can be obtained.

[Form 41] Furthermore, the display program of form 41 is the display program of any one of forms 38 to 40,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
With this 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 display device according to mode 36 can be obtained.

[Form 42] Furthermore, the display program of form 42 is the display program of any one of forms 38 to 41,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets. To do.
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 display device according to the thirty-seventh aspect are obtained.

[Mode 43] On the other hand, in order to achieve the above object, a computer-readable storage medium according to mode 43 is provided.
A computer-readable storage medium storing the display program according to any one of forms 38 to 42.
As a result, the display program according to any one of Embodiments 38 to 42 is transmitted to a consumer such as a user via a computer-readable storage medium such as a CD-ROM, DVD-ROM, FD, or semiconductor chip. It can be provided easily and reliably.

[Form 44] On the other hand, in order to achieve the above object, the display method of form 44 includes:
A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from N ≧ 2) of pixel values, there display method performs display processing based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A determination process step of sequentially performing the determination process on the pixel value using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color corresponding to the threshold value;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A display data generation step for generating display data based on the image data composed of the pixel values converted in the N-value conversion step;
A display step of executing display processing based on the display data generated in the display data generation step.
Thereby, the same operation and effect as those of the display device of the form 33 can be obtained.

[Form 45] Furthermore, the display method of form 45 is the display method of form 44.
In the determination processing step, each threshold value of the threshold set read in the threshold value reading step is equal to the number of colors of the image data, and the corresponding color determination is performed in the determination processing unit for each color performing the determination processing. It distributes to a processing unit, and causes the plurality of determination processing units to execute the determination processing on the pixel values of the respective colors in parallel.
Thereby, the same operation and effect as those of the display device in the form 34 can be obtained.

[Form 46] Furthermore, the display method of form 46 is the same as the display method of form 45,
The determination processing in the determination processing step is performed for each row or column of each color of the image data.
Thereby, the same operation and effect as those of the display device in the form 35 are obtained.

[Form 47] Furthermore, the display method of form 47 is the display method of any one of forms 44 to 46,
The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The shift amount of the reading start position is H / C or W / C.
Thereby, the same operation and effect as those of the display device in the form 36 are obtained.

[Form 48] Furthermore, the display method of form 48 is the display method of any one of forms 44 to 47,
The plurality of threshold sets are stored in a storage area having the same address for each of the predetermined number of threshold sets in a storage area where the addresses are continuous for each predetermined number of the threshold sets. To do.
Thereby, the same operation and effect as those of the display device in the form 37 can be obtained.

[First Embodiment]
A first embodiment of the present invention will be described below with reference to the drawings. 1 to 17 show a printing apparatus, a printing program, a printing method, an image processing apparatus, an image processing program, an image processing method, and a storage medium storing the program according to the first embodiment of the invention. It is.

First, the configuration of the printing apparatus according to the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram showing a configuration of a printing apparatus 1 according to the first embodiment of the present invention.
As shown in FIG. 1, the printing apparatus 1 includes an image data acquisition unit 10 that acquires M-value (M ≧ 3) image data from an external device and the like, and resolution conversion and color conversion for the acquired image data. And an image processing unit 11 that performs various image processing such as N-value processing using a dither method to convert M-value image data into N-value image data, and generates print data based on the converted image data. The print data generation unit 12 and the print unit 13 that executes print processing based on the print data are included.

The image data acquisition unit 10 receives M-value image data for printing sent from a print instruction apparatus (not shown) such as a personal computer (PC) or a printer server connected to the printing apparatus 1 via a network or the like. A function of acquiring or directly reading and acquiring from an image (data) reading device such as a scanner or a CD-ROM drive (not shown) is provided.
The print data generation unit 12 generates print data (print data) that can be interpreted by the printing unit 13 based on the image data converted into N values in the image processing unit 11 (hereinafter referred to as N-valued data). It is supposed to provide the function to do.

  The printing unit 13 includes a print head in which nozzle modules corresponding to CMYK colors are formed, and moves one or both of a medium (hereinafter referred to as a print medium) used for printing such as printing paper and / or a print head. An ink jet printer configured to form a predetermined image composed of a large number of dots on the print medium by ejecting ink from the nozzle module formed on the print head in the form of dots, respectively. In addition to this, a print head feed mechanism (not shown) that reciprocates the print head in the width direction on the print medium (in the case of a multi-pass type), a paper feed mechanism (not shown) for moving the print medium, and the print data Well-known components such as a print controller mechanism (not shown) for controlling the ink ejection of the print head based on It is constructed from.

Further, a detailed configuration of the image processing unit 11 will be described with reference to FIG. FIG. 2 is a block diagram illustrating a detailed hardware configuration of the image processing unit 11.
As shown in FIG. 2, the image processing unit 11 includes a first memory 100, a second memory 101, an address generation unit 102, a resolution conversion unit 103, a color conversion unit 104, and a threshold data distribution unit 105. The first to fourth dither processing units 106 to 109 are included.

The first memory 100 is a memory that stores reference dither matrix data common to each color in the image data after color conversion. Further, the threshold value data of the designated address is read in response to a data read command from the address generation unit 102 and is output to the threshold data distribution unit 105.
Here, the reference dither matrix has a configuration in which a predetermined threshold value is arranged in a two-dimensional matrix with H rows × W columns (H and W are integers of 2 or more).

  Further, when storing the reference dither matrix in the first memory 100, first, the threshold selection start position for the image data of each color from the reference dither matrix is matched with the number of colors C of the image data (C is an integer of 2 or more). Thus, the selection start position of each color is set so as to be shifted in row units (H / C) or column units (W / C) so as to be different from the other colors. Next, a threshold value is selected one by one from the selection start position of each color in the row direction or the column direction in order, one threshold value before the selection start position of the other color, and a set of threshold values for each color is sequentially selected. Forming a set of thresholds and dividing the reference dither matrix into a plurality of threshold sets. Then, the reference dither matrix thus divided into a plurality of threshold sets is stored in the storage area in which the addresses of the first memory 100 are consecutive in the order in which they are formed from the threshold set including the threshold values of the selection start positions.

  The second memory 101 is a frame memory that stores the image data acquired by the image data acquisition unit 10, and is a two-dimensional matrix of X rows × Y columns (X and Y are integers of X ≧ H and Y ≧ W). The image data in which the pixel values are arranged is stored in the arrangement order. In addition, pixel data at a specified address is read in accordance with a data read command from the address generation unit 102 and is output to the resolution conversion unit 103.

  The address generation unit 102 cyclically sets the threshold set used in the first to fourth dither processing units 106 to 109 in the subsequent stage from the first memory 100 with respect to the plurality of threshold sets stored in the first memory 100. Addresses for repeated reading are sequentially generated, a data read command for the generated addresses is output to the first memory 100, and the generated addresses are output to the threshold data distribution unit 105. In addition, the pixel values (pixel data) of each color corresponding to the threshold set sequentially read from the first memory 100 used in the first to fourth dither processing units 106 to 109 in the subsequent stage are stored one by one from the second memory 101. An address for sequentially reading in parallel is generated, a data read command for the generated address is output to the second memory 101, and the generated address is output to the threshold data distribution unit 105.

The resolution conversion unit 103 processes the pixel data input from the second memory 101 so that the resolution of the image data stored in the second memory 101 becomes a resolution corresponding to the print resolution. Then, the processed pixel data is output to the color conversion unit 104. If there is no need to convert the resolution, the pixel data is output to the color conversion unit 104 without being processed.
When the pixel data input from the resolution conversion unit 103 is data in a color space other than CMYK, the color conversion unit 104 converts the input pixel data into CMYK color space data. Then, the pixel data of each color after conversion is separately output to the dither processing unit corresponding to each color in the first to fourth dither processing units 106 to 109 for each color. If the pixel data input from the resolution conversion unit 103 is CMYK color space data, the pixel data of each color is directly associated with each color in the first to fourth dither processing units 106 to 109 without performing conversion processing. Output to the dither processing unit.

The threshold data distribution unit 105 sequentially acquires each threshold data included in the threshold set input from the first memory 100 from the address generation unit 102 based on each address of the threshold set and the address of the pixel data of each color. The first to fourth dither processing units 106 to 109 are assigned to the dither processing units corresponding to the respective colors.
The first dither processing unit 106 corresponds to Cy (cyan) among the four colors of CMYK, compares the Cy pixel data with the corresponding threshold value, and determines the pixel data based on the magnitude relationship. Whether or not to form dots is determined. Then, based on the determination result, the pixel data of M-value Cy is converted to N-value data (hereinafter referred to as N-valued data). Then, the N-value data is output to the print data generation unit 12. Further, a detailed configuration of the first dither processing unit 106 will be described with reference to FIG. Here, FIG. 3 is a block diagram showing a detailed configuration of the first dither processing unit 106.

As shown in FIG. 3, the first dither processing unit 106 includes a determination processing unit 106a and an N-value conversion unit 106b.
The determination processing unit 106a compares the pixel value (density value) indicated by the pixel data input from the color conversion unit 104 with the threshold value indicated by the threshold data input from the threshold data distribution unit 105, and the pixel value is When the threshold value is equal to or greater than the threshold value, it is determined that a dot is formed for the pixel value. When the pixel value is less than the threshold value, it is determined that no dot is formed for the pixel value. Then, this determination result is output to the N-value conversion unit 106b.

The N-value conversion unit 106b converts the pixel value to a predetermined value when it is determined to form a dot based on the determination result input from the determination processing unit 106a. 0 ".
For example, when the printing unit 13 has a print head that forms dots of a single size, the pixel data of M value is converted into binary (N = 2) data. That is, when it is determined that a dot is to be formed, the pixel value is converted to, for example, “255”, and when it is determined that a dot is not to be formed, the pixel value is converted, for example, to “0”.

In the case where the printing unit 13 includes a print head that forms dots of a plurality of sizes, when it is determined that dots are to be formed, the pixel value is converted into a numerical value corresponding to the size.
Alternatively, the input pixel value may be converted once, and the converted data may be compared with a threshold value for conversion. In particular, when using a plurality of dots, for example, a method of converting pixel values based on printing conditions such as a dot diameter and a printing resolution and a recording rate of specific dots described in “JP 2000-79710 A” Can also be processed. In this case, regarding the comparison processing with the one-pixel threshold value data, it is possible to compare the threshold value at the shifted position and the converted value of the pixel corresponding to each size dot by using this method.

  The second dither processing unit 107 corresponds to Mg (magenta) of the four colors of CMYK, compares the pixel data of Mg with the corresponding threshold value, and determines the pixel data based on the magnitude relationship. Whether or not to form dots is determined. Then, based on this determination result, the pixel data of M-value Mg is converted into N-value data. The detailed configuration is the same as that of the first dither processing unit 106 except that the data to be handled is changed to Mg pixel data and threshold data corresponding to the Mg pixel data.

  The third dither processing unit 108 corresponds to Ye (yellow) of the four colors CMYK, compares the pixel data of Ye with a corresponding threshold value, and determines the pixel data based on the magnitude relationship. Whether or not to form dots is determined. Then, based on the determination result, the pixel data of the M-value Ye is converted into N-valued data. The detailed configuration is the same as that of the first dither processing unit 106 except that the data to be handled is changed to the pixel data of Ye and the threshold data corresponding thereto, and thus the description thereof is omitted.

  The fourth dither processing unit 109 corresponds to Bk (black) among the four colors of CMYK, compares the pixel data of Bk with the corresponding threshold value, and determines the pixel data based on the magnitude relationship. Whether or not to form dots is determined. Based on this determination result, the pixel data of Mk Bk is converted into N-valued data. The detailed configuration is the same as that of the first dither processing unit 106 except that the data to be handled is changed to the Bk pixel data and the threshold data corresponding to the Bk pixel data.

  Here, the printing apparatus 1 is a computer system for realizing various controls for printing, various controls of the image processing unit 11, the image data acquisition unit 10, the print data generation unit 12, the printing unit 13, and the like on software. As shown in FIG. 4, the hardware configuration includes a central processing unit (CPU) 60 that is responsible for various controls and arithmetic processing, and a main storage device (Main Storage). A RAM (Random Access Memory) 62 and a ROM (Read Only Memory) 64 which is a read-only storage device are connected to a PCI (Peripheral Component Interconnect) (PCI) bus or an ISA (Industrial Standard Arc). In addition to being connected by various internal and external buses 68 such as a (hecture) bus, an external storage device (Secondary Storage) 70 such as an HDD (Hard Disk Drive) is connected to the bus 68 via an input / output interface (I / F) 66, The printing unit 13, an output device 72 such as a CRT and an LCD monitor, an input device 74 such as an operation panel, a mouse, a keyboard and a scanner, and a network L for communicating with a print instruction device (not shown) and the like are connected.

  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 via the medium or the communication network L such as the Internet are similarly loaded into the RAM 62, and the CPU 60 performs various operations according to instructions described in the program loaded in the RAM 62. Each function of each unit as described above can be realized by performing predetermined control and arithmetic processing by making full use of resources.

Furthermore, the flow of the printing process of the printing apparatus 1 will be described with reference to FIG. Here, FIG. 5 is a flowchart showing a printing process in the printing apparatus 1.
As shown in FIG. 1, the printing process first proceeds to step S100, and the image data acquisition unit 10 receives print instruction information from an external device connected via the network cable L, or It is determined whether or not there has been a print instruction due to the input of print instruction information via the input device 74. If it is determined that there has been a print instruction (Yes), the process proceeds to step S102; otherwise (No ) Repeats the determination process until there is a print instruction.

When the process proceeds to step S102, the image data acquisition unit 10 outputs the image data corresponding to the print instruction to the external device, a recording medium such as a CD-ROM or a DVD-ROM, and a storage device 70 such as an HDD as described above. And the process proceeds to step S104.
In step S104, the image data acquisition unit 10 stores the image data acquired in step S102 in the second memory 101 of the image processing unit 11, and the process proceeds to step S106.

In step S106, the CPU 60 transmits an image processing execution command to the image processing unit 11, causes the image processing unit 11 to execute the image processing, and proceeds to step S108.
In step S108, the print data generation unit 12 determines whether or not N-valued data has been acquired from the image processing unit 11. If it is determined that it has been acquired (Yes), the process proceeds to step S110; In case (No), the determination process is repeated until acquisition.

When the process proceeds to step S110, the print data generation unit 12 generates print data based on the N-value data acquired in step S108, and the process proceeds to step S112.
In step S112, the print data generation unit 12 determines whether or not the print data for the image data acquired in step S102 is completed. If it is determined that the print data is completed (Yes), the process proceeds to step S114. If not (No), the process proceeds to step S108.

When the process proceeds to step S114, the print data generation unit 12 outputs the completed print data to the printing unit 13, and the process proceeds to step S116.
In step S116, the printing unit 13 executes the printing process based on the print data input from the print data generation unit 12, and ends the process.

Next, the operation of the present embodiment will be described with reference to FIGS.
Here, FIG. 6A is a diagram showing an example of the threshold data array of the reference dither matrix (8 rows × 8 columns), (b) is Cy (cyan), and (c) is Mg (magenta). , (D) is a diagram showing an example of threshold data arrangement when the selection start position is shifted in units of two rows for Ye (yellow) and (e) for Bk (black). FIG. 7 is a diagram showing a storage configuration of reference dither matrix data in the first memory 100. FIG. 8A is a diagram illustrating an example of a pixel data selection method, and FIG. 8B is a diagram illustrating an example of a dither matrix application method. FIGS. 9A and 9B are diagrams illustrating an example of a method for reading the reference dither matrix data from the first memory 100.

Here, the dither matrix used in the first to fourth dither processing units 106 to 109 of the image processing unit 11 will be described. Here, it is assumed that the reference dither matrix of 8 rows × 8 columns (H = 8, W = 8) shown in FIG. Further, the description will be made assuming that the number of colors of the image data is four colors of CMYK.
First, the selection start position of each color of CMYK is determined so that the start position of each color is different from the start position of the other colors. Here, in the reference dither matrix shown in FIG. 6A, it is determined so that the start position is shifted by H / C (8/4 = 2) rows with respect to the start position of each color.

First, the threshold of the selection start position for Cy is set to a11 in the reference dither matrix shown in FIG. Next, the starting position for Mg is a31 at a position shifted by two rows from a11. Similarly, the start position for Ye is a51 at a position shifted by two lines from a31, and the start position for Bk is a71 at a position shifted by two lines from a51.
Here, when the dither matrix of each color is configured by shifting the arrangement of the reference matrix in units of two rows, the dither matrix of each color of Cy, Mg, Ye, and Bk is shown in FIGS. 6B to 6E, respectively. It becomes the structure shown in.

  For example, in the case of Mg, as shown in FIG. 6C, the first to sixth lines are the third to eighth lines of the reference dither matrix, and the seventh to eighth lines are the reference lines. From the first line to the second line of the dither matrix. That is, when the selection start position is in the middle row of the reference dither matrix, the middle row is the start row, and the array contents from the first row to the eighth row (the last row), and the middle row from the first row to the middle row. A dither matrix is composed of the array contents up to the previous row. Similarly, the dither matrix for Ye has the configuration shown in FIG. 6D, and the dither matrix for Bk has the configuration shown in FIG. In the present invention, the dither matrix shown in FIGS. 6C to 6E is not created and four dither matrices corresponding to the respective colors are stored in the memory, but only one reference matrix is stored in the memory. To do. That is, by selecting the threshold values in the row direction in order from the determined selection start position in the reference matrix and cyclically with respect to the reference dither matrix, the same arrangement order as in FIGS. 6C to 6E is obtained. Read threshold data in order.

  When the selection start position for each color is determined, the reference dither matrix is stored in the first memory 100. However, in the present invention, instead of simply storing the reference matrix in the memory in the order of arrangement, as described above, when storing the reference dither matrix in the first memory 100, first, the reference dither matrix is stored in a plurality of threshold sets. Divide into

  Specifically, in the reference dither matrix, thresholds are selected one by one in the row direction from a11, a31, a51, and a71 which are the selection start positions of the respective colors, and a total of four threshold sets for each color are obtained. A plurality of threshold sets are formed as one threshold set. First, a set of threshold values (a11, a31, a51, a71) at the selection start position of each color is the first threshold set. In this way, the process of selecting the threshold value one by one in the row direction from the selection start position of each color and forming the threshold set is performed from the selection start position of each color to the position immediately before the selection start position of the other color. . That is, a11 to a28 including the Cy start position, a31 to a48 including the Mg start position, a51 to a68 including the Ye start position, and a71 to a88 including the Bk start position are performed in parallel. As a result, the reference dither matrix is changed to (a11, a31, a51, a71), (a12, a32, a52, a72), (a13, a33, a53, a73), ..., (a27, a47, a67, a87). ), (A28, a48, a68, a88) can be divided into 16 threshold sets.

  As shown in FIG. 7, the reference dither matrix divided into the 16 threshold sets is stored in the storage area where the addresses of the first memory 100 are continuous (the storage areas where addresses 0000h to 4000h in FIG. 7 are continuous). ) In the order in which the threshold sets are formed, that is, (a11, a31, a51, a71), (a12, a32, a52, a72), (a13, a33, a53, a73), ..., (a27, a47, a67). , A87) and (a28, a48, a68, a88). In the example of FIG. 7, each threshold value is 8 bits (FFh), and each threshold set has a size of 8 × 4 = 32 bits (3FFh). Since there are 16 threshold sets, 32 × 16 = 512 bits, and 16 addresses are set for each 32-bit storage area. That is, one address is set for each threshold set.

Hereinafter, it is assumed that the reference dither matrix is stored in the first memory 100 with the configuration shown in FIG.
First, when the printing apparatus 1 receives printing instruction information from an external apparatus or the like in the image data acquisition unit 10 (step S100), the printing apparatus 1 transmits M-value image data corresponding to the printing instruction information at the transmission source of the printing instruction information. Obtained from an external device or the like (step S102), the obtained image data is stored in the second memory 101 of the image processing unit 11 (step S104). After storing the image data in the second memory 101, the printing apparatus 1 next transmits an image processing start command to the image processing unit 11 to execute the image processing (step S106). The image processing unit 11 may detect the image data stored in the second memory 101 and execute the image processing without receiving a command.

  When the image processing is executed, the address generation unit 102 generates an address for reading the pixel data of each color of the image data one by one from the common start position in parallel with each color, and issues a data read command for the address. 2 outputs to the memory 101 and outputs the generated address to the threshold data distribution unit 105.

  Here, it is assumed that the image data acquired by the image data acquisition unit 10 is data in the RGB color space. Accordingly, pixel data is selected in order from the start position common to the RGB image data in accordance with the dither matrix size and the threshold data reading method. Here, as shown in FIG. 8A, first, the pixel data of the upper left pixel P11 of the image is set as the start position for each color. The start position common to each color is made to correspond to the start position of each color of the dither matrix. As described above, since the size of the dither matrix is 8 rows × 8 columns, the address generation unit 102 performs pixel data one by one in the order of (1) to (64) in FIG. An address is generated so that is read. In other words, each row is selected in order from left to right. When the last pixel data in each row (which varies depending on the size of the dither matrix) is reached, it moves to the next lower row and similarly from left to right. Select in turn. As a result, in one reading, pixel data of three colors of RGB is read out in parallel, one in total, for a total of three. When the pixel data of each color pixel P88 is read out, the pixel data selection start position is changed in accordance with the shift direction of the dither matrix. Here, as shown in FIG. 8B, when the reading of the threshold data for 64 pixel data corresponding to the dither matrix is completed, the entire dither matrix is shifted to the right by the size. In this way, each time reading is completed, the image is shifted to the right, and when the right end of the image is reached, the entire dither matrix is then shifted downward by that size and moved to start from the left end of the image. . Therefore, as shown in FIG. 8A, when the pixel data of the pixel P88 is read out, the pixel data of the pixel P19 is set to the common start position (1) for each color, and similarly, 64 pixel data for each color in parallel. Addresses are generated so that they are read one by one in order.

In this way, three pixel data for each of the RGB colors are sequentially read from the second memory 101 and output to the resolution conversion unit 103.
The address generation unit 102 generates an address for reading the threshold set stored in the storage area of the addresses 0000h to 4000h in parallel with the pixel data reading process, and sends a data read command for the address to the first The data is output to the memory 100, and the generated address is output to the threshold data distribution unit 105.

  Specifically, as shown in FIG. 9A, an address for sequentially reading out each threshold set stored in the storage area of addresses 0000h to 4000h one by one in the order of this address is generated. A data read command is output to the first memory 100, and the generated address is output to the threshold data distribution unit 105. As a result, the threshold sets are sequentially read from the first memory 100 one by one in the order of the addresses, and are output to the threshold data distribution unit 105.

  In addition, as shown in FIG. 7, one threshold set is continuously stored for each address in the storage area of addresses 0000h to 4000h. That is, since the increment of the address value is uniform by 32 bits, the address can be generated simply by incrementing the increment to the start address (0000h). Accordingly, since burst transfer is possible, it is possible to read out the threshold set from the first memory 100 at high speed and output it to the threshold data distribution unit 105.

  In addition, when the threshold set (a28, a48, a68, a88) of the address 4000h is read, the address generation unit 102 subsequently reads an address for reading the threshold set stored in the storage area of the addresses 0000h to 4000h. A data read command for this address is output to the first memory 100, and the generated address is output to the threshold data distribution unit 105. That is, the address generation unit 102 sets addresses 0000h to 4000h until image processing using the dither matrix for the image data to be processed is completed, such as 0000h to 4000h → 0000h to 4000h → 0000h to 4000h →. On the other hand, the addresses are generated so that the threshold set is read cyclically and in the order of the addresses.

On the other hand, when the pixel data is input from the second memory 101, the resolution conversion unit 103 reduces or increases the number of pixels according to the number of pixels with respect to the print resolution. Here, assuming that there is no excess or deficiency, RGB pixel data is output to the color conversion unit 104 as it is.
When the RGB pixel data is input from the resolution conversion unit 103, the color conversion unit 104 converts the RGB pixel data into CMYK pixel data. Then, the converted four pixel data of each color of CMYK are separately output to the dither processing units corresponding to the respective colors in the first to fourth dither processing units 106 to 109.

  On the other hand, the threshold data distribution unit 105 determines each threshold data included in the threshold set read from the first memory 100 from the size of the reference dither matrix, the number of corresponding colors, the shift amount of the selection start position, and the like. Based on the rule, the first to fourth dither processing units 106 to 109 respectively output to the dither processing units corresponding to the respective colors.

  Specifically, the threshold set read from the storage area at addresses 0000h to 4000h in the order shown in FIG. 9A is, for example, the address set at address 0000h as shown in FIG. For the threshold set (a11, a31, a51, a71), the threshold data a11 is stored in the first dither processing unit 106 for Cy, the threshold data a31 is stored in the second dither processing unit 107 for Mg, and the threshold data a51 is displayed in Ye. The threshold data a71 is allocated to the third dither processing unit 108 for Bk and the fourth dither processing unit 109 for Bk. That is, 16 threshold values sets (a11, a31, a51, a71), (a12, a32, a52, a72), (a13, a33, a53, a73), ..., (a27, a47) read out first time. , A67, a87) and (a28, a48, a68, a88), the threshold set starts from the selection start position of each color, and therefore the dither of each color is based on the positional relationship of (Cy, Mg, Ye, Bk). The threshold data corresponding to the processing unit is distributed.

  On the other hand, when the first dither processing unit 106 receives threshold data from the threshold data distribution unit 105 and receives Cy pixel data from the color conversion unit 104 in the determination processing unit 106a, the input threshold data is input. When the pixel value indicated by the pixel data is equal to or greater than the threshold value indicated by the threshold data, it is determined that a dot is to be formed for the pixel data, and when the pixel value is less than the threshold value, it is determined that no dot is formed. . Next, the N-value conversion unit 106b converts the pixel value into a value corresponding to the dot size formed by the print head when it is determined from the determination result of the determination processing unit 106a that a dot is to be formed. Is generated. Specifically, when the print head can form only one type of dot, the pixel value is converted into a value corresponding to the dot size or a value such as “1” indicating formation of a dot, and an N value Generate data. On the other hand, when it is determined that no dot is to be formed, N-valued data in which the pixel value is converted to “0” is generated. Then, the generated N-value data is output to the print data generation unit 12.

  Similarly to the first dither processing unit 106, the second to fourth dither processing units 107 to 109 also each threshold value data input from the threshold data distribution unit 105 and each color pixel input from the color conversion unit 104. Based on the data, the determination processing units 106a to 109a determine whether or not to form a dot for each input pixel data, and generate N-value data based on the determination result. Then, the generated N-valued data is output to the print data generation unit 12 respectively.

Note that the first to fourth dither processing units 106 to 109 operate in parallel, generate N-ary data at approximately the same time, and output to the print data generation unit 12.
By performing such processing on the threshold value set stored in the storage area from address 0000h to 4000h read out the first time, image data of 8 rows × 8 columns corresponding to the size of the dither matrix N-ary data can be generated for the pixel data up to the second line of each color.

  When the threshold set is read in this address order from the storage area of addresses 0000h to 4000h by the second read subsequent to the first read, as shown in FIG. 9B, for example, the threshold set (a11 of address 0000h , A31, a51, a71), the threshold data a11 is used for the Bk fourth dither processing unit 109, the threshold data a31 is used for the Cy first dither processing unit 106, and the threshold data a51 is used for Mg. The threshold data a71 is distributed to the second dither processing unit 107 and the third dither processing unit 108 for Ye. As described above, the dither matrix for each color has a configuration in which the selection start position of each color in the reference dither matrix is shifted in units of two lines with respect to the other colors, and as shown in FIGS. In the third and subsequent rows of the dither matrix for each color, the threshold data starting from the selection start position for the other color correspond to each other. That is, for the third and fourth rows of the dither matrix, the positional relationship of (Bk, Cy, Mg, Ye) is established with respect to the 16 threshold sets, so that the dither processing unit for each color is sent to the dither matrix. , The first to fourth dither processing units 106 to 109 perform pixel data up to the fourth row of each color in the image data of 8 rows × 8 columns corresponding to the size of the dither matrix. N-valued data can be generated.

  When the threshold set is read out in the order of this address from the storage area of the address 0000h to 4000h by the third reading following the second reading, as shown in FIG. 9B, for example, the threshold set (a11 at the address 0000h). , A31, a51, a71), the threshold data a11 is used for the third dither processing unit 108 for Ye, the threshold data a31 is used for the fourth dither processing unit 109 for Bk, and the threshold data a51 is used for Cy. The threshold data a71 is distributed to the second dither processing unit 107 for Mg. That is, for the fifth and sixth rows of the dither matrix, as shown in FIGS. 6B to 6E, (Ye, Bk, Cy, Mg) with respect to the above 16 threshold sets. Therefore, by assigning the threshold data corresponding to the dither processing unit for each color, the pixel data up to the sixth row of each color in the image data of 8 rows × 8 columns corresponding to the size of the dither matrix is assigned. Thus, the first to fourth dither processing units 106 to 109 can generate N-valued data.

  Then, when the threshold value set is read out from the storage area of the addresses 0000h to 4000h by the fourth reading subsequent to the third reading, as shown in FIG. 9B, for example, the threshold set of the address 0000h is set. If (a11, a31, a51, a71), this time, the threshold data a11 is stored in the second dither processing unit 107 for Mg, the threshold data a31 is stored in the third dither processing unit 108 for Ye, and the threshold data a51 is stored. The threshold data a71 is allocated to the fourth dither processing unit 109 for Bk and the first dither processing unit 106 for Cy. That is, for the seventh and eighth rows of the dither matrix, as shown in FIGS. 6B to 6E, (Mg, Ye, Bk, Cy) with respect to the above 16 threshold sets. Therefore, by assigning the threshold data corresponding to the dither processing unit for each color, the pixel data up to the 8th row for each color in the image data of 8 rows × 8 columns corresponding to the size of the dither matrix is assigned. Thus, the first to fourth dither processing units 106 to 109 can generate N-valued data. In other words, by reading out the threshold set four times from the storage area at addresses 0000h to 4000h in the order of the addresses, it is possible to generate N-valued data for a range of 8 rows × 8 columns in CMYK 4-color image data.

The series of processes described above are repeated so that the dither matrix for each color shifts as shown in FIG.
On the other hand, when the N-value data is input from the image processing unit 11, the print data generation unit 12 generates print data based on the N-value data (step S110). When print data for the acquired image data is generated (“Yes” branch in step S112), the print data is output to the printing unit 13 (step S114).

When the print data is input from the print data generation unit 12, the printing unit 13 executes a printing process based on the print data (step S116). As a result, a printed matter in which an image of the image data is printed on a predetermined print medium is output from the printing unit 13.
Furthermore, in the present embodiment, the storage configuration of the threshold set in the first memory 100 can be a configuration other than the configuration shown in FIG. Here, FIGS. 10A and 10B are diagrams illustrating an example of another storage configuration of the threshold set in the first memory 100. FIG.

  The example shown in FIG. 10A is an example in which the address of the first memory 100 is set for every 16 bits (0200h), and 4 consecutive addresses having such a value are included in the threshold set. One threshold data is divided into two, and each of the two threshold data is stored in a storage area of one address. That is, one threshold set is divided into two addresses and stored. In this case, for example, since one threshold set is divided and stored in two addresses 0000h and 0200h, the address generation unit 102 starts the threshold set stored in the storage area of addresses 0000h to 4000h. An address incremented by 16 bits (0200h) with respect to the address (0000h) is generated, a data read command for the address is output to the first memory 100, and the generated address is output to the threshold data distribution unit 105.

On the other hand, the threshold data distribution unit 105 holds, for example, the threshold data previously input until threshold data for one threshold set is input, and distribution after the threshold data for two addresses is input. Execute the process.
In the case of the example shown in FIG. 10B, the address of the first memory 100 is set every 8 bits (0100h), and a threshold value set is set for consecutive addresses having such values. Are stored in storage areas of four consecutive addresses one by one in order. In this case, for example, one threshold set is divided and stored into four addresses of addresses 0000h, 0100h, 0200h, and 0300h. An address obtained by incrementing the set by 8 bits (0100h) with respect to the start address (0000h) is generated, a data read command for this address is output to the first memory 100, and the generated address is output to the threshold data distribution unit 105. Output to.

On the other hand, the threshold data distribution unit 105 holds, for example, the threshold data previously input until threshold data for one threshold set is input, and distribution after the threshold data for four addresses is input. Execute the process.
Furthermore, in the present embodiment, processing can be performed without depending on the size of the reference dither matrix.

Here, FIG. 11A is a diagram showing an example of the arrangement of the reference dither matrix of 16 rows × 12 columns, and FIG. 11B shows an example of the storage configuration of the threshold set for the reference dither matrix of FIG. FIG.
So far, the dither matrix of 8 rows x 8 columns has been described as an example. However, the dither matrix is not limited to this size. For example, the dither matrix is expanded to 16 rows x 12 columns as shown in FIG. Even in the case of 8 rows × 8 columns, processing can be performed. Also in this case, as in the case of 8 rows × 8 columns, “H / C = 16/4 = 4” for four colors of CMYK, first, the shift amount of the selection start position is obtained, and the reference dither matrix The threshold selection start position for each color is determined as Cy: a11, Mg: a51, Ye: a91, Bk: aD1. Then, based on this start position, as shown in FIG. 11B, the reference dither matrix is divided into 192 threshold sets and stored in the storage area (the area from 00000h to 30000h) where the addresses of the first memory 100 are continuous. Remember in order. In this case, in the first reading of the 192 threshold sets, N-valued data is generated for the pixel data up to the fourth column in the corresponding 16-row × 12-column area of the image data of each color. Become. In the fourth reading, the generation of N-valued data for all pixel data in the region of 16 rows × 12 columns in the image data is completed. It should be noted that the processing is not limited to a size larger than 8 rows × 8 columns, but if there are a number of rows and columns greater than the number of colors, the same processing is performed even if the size is reduced to 4 rows × 4 columns. It can be carried out.
Further, in the present embodiment, the same processing as described above can be performed not only on data in four color spaces such as CMYK but also on data in color spaces of other colors.

  Here, FIG. 12A is a diagram illustrating an example of a reference dither matrix (8 rows × 8 columns), and FIGS. 12B and 12C are two colors in which start positions are shifted in units of 4 rows. (D) is a figure which shows an example of the storage structure of the threshold set with respect to the reference | standard dither matrix of (a), and an example of the read-out method.

  For example, with respect to the reference dither matrix of 8 rows × 8 columns shown in FIG. 12A, “H / C = 8/2 = 4” and first, the shift amount of the selection start position is obtained, and the reference dither matrix The threshold selection start position for each color is determined as C1: a11 and C2: a51, where the two colors are C1 and C2, respectively. In this case, a dither matrix having an array content as shown in FIG. 12B is formed for C1, and a dither matrix as shown in FIG. 12C is formed for C2. Next, the reference dither matrix shown in FIG. 12A is divided into a plurality of threshold sets. Here, since the number of colors is two, one threshold is selected in order in the row direction from each of the selection start positions a11 and a51 of each color, and a total of two threshold values for each color is set to one. Thirty-two threshold sets are formed as one threshold set. Then, the 32 threshold sets thus formed are stored in the storage area where the addresses of the first memory 100 are continuous. As shown in FIG. 12D, the address of the first memory 100 is set for every 16 bits (01FFh), and each threshold set in the 32 threshold sets is set to 0000h to 4000h in order from the threshold set at the selection start position. Are stored one by one for each address in a continuous storage area.

  In this case, by the first reading of the 32 threshold sets, for example, C1 and C2 are processed using the first and second dither processing units 106 and 107, respectively, to correspond to the dither matrix in the image data. N-valued data can be generated for pixel data up to the fourth column in a region of 8 rows × 8 columns. At this time, since the positional relationship of (C1, C2) is established for the read threshold set, the threshold data distribution unit 105 distributes the threshold data to the corresponding dither processing unit based on this positional relationship. Subsequently, N-ary data for pixel data of the remaining half (5 to 8 columns) of the region of 8 rows × 8 columns can be generated by the second reading. This completes the generation of N-valued data for all pixel data in the region of 8 rows × 8 columns, including the first time. Note that the positional relationship of (C2, C1) is established for the threshold set read for the second time.

  Further, in the present embodiment, N-valued data is generated using threshold sets corresponding to the four colors of CMYK in the storage configuration shown in FIG. 7 for the color space of the two colors (C1, C2). It is also possible to perform processing. Here, FIG. 13A is a diagram illustrating an example of a reference dither matrix, FIGS. 13B and 13C are diagrams illustrating a configuration example of a dither matrix in the case of two colors, and FIG. 6A is a diagram illustrating an example of a threshold set reading method for each reference dither matrix in FIG.

  When the threshold set corresponding to the four colors of CMYK shown in FIG. 7 is used, the selection start position corresponding to Cy in the reference dither matrix shown in FIG. Let the selection start position be the selection start position of C2. Then, a dither matrix having an array content as shown in FIG. 13B is formed for C1, and a dither matrix as shown in FIG. 13C is formed for C2.

  For example, if processing is performed on C1 and C2 using the first and second dither processing units 106 and 107, respectively, the method of reading the threshold set from the first memory 100 (reading order, number of readings, etc.) is as follows. 9B, but the threshold data distribution unit 105 distributes two of the four threshold data included in the threshold set to the corresponding dither processing unit. There is a need. That is, as shown in FIG. 13D, in the first reading, the positional relationship of (C1, C2,-,-) is established for the 16 threshold data read at this time. Here, “-” indicates that the threshold data at that position is not used in the first and second dither processing units 106 and 107. Similarly, the positional relationship of (−, C1, C2, −) is established in the second reading, and the positional relationship of (−, −, C1, C2) is established in the third reading. In the second reading, the positional relationship of (C2,-,-, C1) is established. That is, 16 threshold sets are repeatedly read out four times, and the threshold data is distributed to the first and second dither processing units 106 and 107 according to the positional relationship shown in FIG. N-ary data for all pixel data of 8 rows × 8 columns corresponding to the dither matrix in the image data can be generated.

Further, until now, an example has been described in which the threshold selection start position of each color in the reference dither matrix is determined by shifting by a predetermined row unit. However, in the present embodiment, the selection start position is further set by a predetermined column unit. It is also possible to determine the selection start position of the threshold value by shifting by.
Here, FIG. 14A is a diagram showing an example of the threshold data array of the reference dither matrix (8 rows × 8 columns), where (b) is Cy (cyan), (c) is Mg (magenta), (D) is a diagram showing an example of threshold data arrangement when the selection start position is shifted in units of two columns with respect to Ye (yellow) and (e) with respect to Bk (black). FIG. 15 is a diagram illustrating a storage configuration of reference dither matrix data in the first memory 100 and a method for reading a threshold set. FIGS. 16A and 16B are diagrams illustrating an example of a method for reading the reference dither matrix data from the first memory 100.

First, with respect to the reference dither matrix of 8 rows × 8 columns in FIG. 14A, the selection start position of each color of CMYK is determined so that the start position of each color is different from the start position of other colors. Here, in the reference dither matrix shown in FIG. 14A, the start position is determined so as to be shifted by W / C (8/4 = 2) columns from the start position of each color.
First, the dither matrix for Cy is set to the same array content as the reference dither matrix in FIG. The threshold value for the selection start position is set to a11. Next, the start position for Mg is set to a13 at a position shifted by two columns from a11 in the reference dither matrix. Similarly, the start position for Ye is a15 at a position shifted by two columns from a13, and the start position for Bk is a17 at a position shifted by two lines from a51.

Here, when the dither matrix of each color is configured by shifting the arrangement of the reference matrix in units of two columns, the dither matrix of each color of Cy, Mg, Ye, and Bk is shown in FIGS. 14B to 14E, respectively. It becomes composition.
For example, in the case of Mg, as shown in FIG. 14 (c), the first to sixth columns are the third to eighth columns of the reference dither matrix, and the seventh to eighth columns are the reference. It becomes the second column from the first column of the dither matrix. That is, when the selection start position is in the middle column of the reference dither matrix, the middle column is set as the start column, and the array contents from the first column to the eighth column (final row), and from the first column to the middle column. A dither matrix is composed of the array contents up to the previous column. Similarly, the dither matrix for Ye has the configuration shown in FIG. 14D, and the dither matrix for Bk has the configuration shown in FIG.

  When the selection start position of each color is determined, the reference dither matrix is first divided into a plurality of threshold sets. Specifically, in the reference dither matrix, threshold values are selected one by one in the column direction from a11, a13, a15, and a17 that are the selection start positions of the respective colors, and a total of four threshold value sets for each color is obtained. A plurality of threshold sets are formed as one threshold set. First, a set of threshold values (a11, a13, a15, a17) at the selection start position of each color is the first threshold set. In this way, the process of selecting the threshold values one by one in order from the selection start position of each color in the column direction and forming the threshold set is performed from the selection start position of each color to the position immediately before the selection start position of each other color. . That is, in the column direction, a11 to a82 including the Cy start position, a13 to a84 including the Mg start position, a15 to a86 including the Ye start position, and a17 to a88 including the Bk start position, respectively. Do in parallel. Thereby, the reference dither matrix is changed to (a11, a13, a15, a17), (a21, a23, a25, a27), (a31, a33, a35, a37), ..., (a72, a74, a76, a78). ) And (a82, a84, a86, a88) can be divided into 16 threshold sets.

  As shown in FIG. 15, the reference dither matrix divided into 16 threshold sets is stored in a continuous storage area of addresses of the first memory 100 (a continuous storage area of addresses 0000h to 4000h in FIG. 15). ) In the order in which the threshold sets are formed, that is, (a11, a13, a15, a17), (a21, a23, a25, a27), (a31, a33, a35, a37), ..., (a72, a74, a76). , A78), (a82, a84, a86, a88). In the example of FIG. 15, each threshold value is 8 bits (FFh), and each threshold set has a size of 8 × 4 = 32 bits (3FFh). Since there are 16 threshold sets, 32 × 16 = 512 bits, and 16 addresses are set for each 32-bit storage area. That is, as in the configuration shown in FIG. 7, one address is set for each threshold set.

Hereinafter, assuming that the reference dither matrix is stored in the first memory 100 with the configuration shown in FIG. 15, image processing in the image processing unit 11 of the printing apparatus 1 will be described. The method for reading out the pixel data of each color is the same as the method shown in FIG. 8A described above.
When the image processing is executed, the address generation unit 102 generates an address for reading the pixel data of each color of the image data one by one from the common start position in parallel with each color, and issues a data read command for this address 2 outputs to the memory 101 and outputs the generated address to the threshold data distribution unit 105.
The address generation unit 102 generates an address for reading the threshold set stored in the storage area of the addresses 0000h to 4000h in parallel with the pixel data reading process, and sends a data read command for the address to the first The data is output to the memory 100, and the generated address is output to the threshold data distribution unit 105.

  Specifically, as shown in FIG. 16 (a), each threshold set stored in the storage area of addresses 0000h to 4000h in sequence is first stored in addresses 0000h to 0400h as shown in FIG. 16 (b). The read threshold sets are read one by one in the order of the addresses, and are circulated from 0400h to 0000h as shown by the arrows in FIG. 15 to generate addresses for repeatedly reading the threshold sets from 0000h to 0400h in this order. . That is, the addresses are generated so that the threshold sets stored in the storage areas of the addresses 0000h and 0400h are cyclically and repeatedly read four times as 0000h → 0400h → 0000h → 0400h → 0000h → 0400h → 0000h → 0400h. The reason for repeatedly reading in this manner is that the reading direction of pixel data from the image data remains in the row direction while the threshold selection start position is shifted in units of columns. That is, since pixel data of an area of 8 rows × 8 columns corresponding to the dither matrix in the image data is sequentially read for each row for each color, N-value conversion is performed on the read CMYK four-color pixel data for each row. In order to generate data, it is necessary to repeatedly read out each of the two threshold sets having consecutive addresses in order of four times in the 16 threshold sets having consecutive addresses. Therefore, after reading out the threshold set stored in 0000h to 0400h four times, each successive two thresholds in the order of 0800h to 0C00h, 1000h to 1400h, ... 3000h to 3400h, 3800h to 4000h Read the set repeatedly 4 times.

  On the other hand, in the reading method shown in FIG. 9B described above, 16 threshold values are sequentially read one by one in the order of addresses from 0000h to 4000h, and this reading for the 16 threshold values is performed at addresses 0000h to 4000h. For example, all the pixel data in the region corresponding to the dither matrix are converted into N-value data by repeating the process four times. In contrast, here, as described above, the addresses are sequentially shifted while reading four times for each of two consecutive threshold sets in the order of addresses 0000h to 4000h, and the last two consecutive threshold values are sequentially read. By reading and processing the threshold set stored in the storage area 3800h to 4000h, which is a set, four times, all pixel data in the area corresponding to the dither matrix is converted to N-value data. Yes. Accordingly, in the first to fourth dither processing units 106 to 109, each of the two threshold sets is repeatedly used four times in succession. Therefore, a high-speed cache memory or the like is provided in the threshold data distribution unit 105, and By caching one threshold set and repeatedly using it from the cache memory, it is possible to reduce the number of readings of each of the two threshold sets once (1/4).

  In addition, as shown in FIG. 16B, the operation of the threshold data distribution unit 105 distributes each threshold data while changing the positional relationship for each number of readings of each of the two threshold sets. Specifically, the two threshold sets have a positional relationship of (Cy, Mg, Ye, Bk) for the first reading, and the two threshold sets have both (Bk, (Cy, Mg, Ye) and the two threshold sets are (Ye, Bk, Cy, Mg) for the third reading, and the two thresholds for the fourth reading. Both sets have a positional relationship of (Mg, Ye, Bk, Cy). Therefore, the threshold data distribution unit 105 distributes the threshold data of each two threshold sets to the first to fourth dither processing units 106 to 109 according to these positional relationships.

  Note that the resolution conversion processing of the resolution conversion unit 103, the color conversion processing of the color conversion unit 104, and the determination processing and the N-value conversion processing in the first to fourth dither processing units 106 to 109 are shifted in units of the predetermined lines. Since this is the same as the operation for determining the threshold selection start position, a description thereof will be omitted.

  As described above, in the present embodiment, the selection start position of the threshold value corresponding to each color of the image data in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit, and selected one by one from the selection start position in the reference dither matrix. A threshold set is formed from the threshold values for each color, and the reference dither matrix is divided into a plurality of threshold sets. The plurality of threshold sets are sequentially stored in the storage area where the addresses of the first memory 100 are consecutive, starting from the threshold set of the selection start position. The reference dither matrix stored in such a storage configuration is read cyclically and repeatedly with respect to the addresses until all pixel data of the image data is converted into N-valued data in ascending order of addresses for each threshold set. . Further, each threshold value data of the read threshold value set is distributed to the corresponding dither processing unit based on a rule determined by the size of the reference dither matrix, the number of colors of the image data, the shift amount of the selection start position, and the like. On the other hand, the pixel data at the position corresponding to the dither matrix is sequentially read out one by one for each color, and after resolution conversion and color conversion, output to the corresponding color dither processing units of the first to fourth dither processing units 106 to 109, respectively. To do.

Then, using the distributed threshold data and the input pixel data, a determination process and an N-value process are performed to generate N-value data.
As a result, only one reference dither matrix needs to be stored in the memory, so that the memory capacity required for the dither matrix can be reduced.
In addition, threshold data is stored in a storage area with continuous addresses in the order of reading and in the form of a threshold set, and this threshold set is cyclically and repeatedly read from the memory in the order of the addresses. Threshold data to be read can be read at high speed.

  In addition, since threshold data can be read at high speed, resolution conversion processing, color conversion processing, and N-valued data generation processing using a dither matrix can be continuously performed on the read pixel data. . Accordingly, in these series of processes, the number of accesses to the memory can be greatly reduced, so that the time from acquisition of image data to completion of printing can be shortened.

  In the first embodiment, the process of storing the reference dither matrix in the first memory 100 corresponds to the reference dither matrix storage means of any one of the forms 1, 6, 12, 17, 22, and 28, and the address Reading processing of threshold data (threshold set) from the first memory 100 by the generation unit 102 and the threshold data distribution unit 105 corresponds to any one of the threshold reading means in the first, second, 17th, and 18th forms, and generates an address. The pixel data reading process from the second memory 101 of the unit 102 corresponds to the pixel value acquisition unit of the form 1 or 17, and the determination processing unit 106a (-109a) is any of the forms 1-3 and 17-19. The N-value conversion unit 106b (˜109b) corresponds to the N-value conversion means of the form 1 or 17.

Further, in the first embodiment, the print data generation unit 12 corresponds to the print data generation unit of form 1, and the print unit 13 corresponds to the print unit of form 1.
In the first embodiment, steps S108 to S114 correspond to the print data generation step of form 6 or 12, and step S116 corresponds to the print step of form 6 or 12.

  In the first embodiment, the configuration in which the threshold set is stored in one first memory 100 has been described. However, the present invention is not limited to this, and the first memory 100 as in the printing apparatus 2 shown in FIG. May be physically divided into four first to first to fourth memories 100a to 100d, and the reference dither matrix data may be divided and stored in these four memories. Here, FIG. 17 is a block diagram illustrating a modification of the printing apparatus 1 according to the first embodiment.

  Specifically, the 16 threshold data a11 to a28 including the Cy selection start position in the reference dither matrix shown in FIG. 6A are stored in the continuous storage area of the address of the 1-1 memory 100a. , 16 threshold data of a31 to a48 including the selection start position of Mg are stored in the continuous storage area of the address of the first-second memory 100b, and 16 threshold values of a51 to a68 including the selection start position of Ye are stored. The data is stored in the continuous storage area of the address of the first to third memory 100c, and the 16 threshold data a71 to a88 including the selection start position of Bk are stored in the continuous storage area of the address of the first to fourth memory 100d. Remember. However, the address of each memory is set every 8 bits for one threshold data. Further, the threshold value data is selected and stored one by one in the row direction (from left to right) for each row from the start position.

  Then, the address generation unit 102 generates addresses so that threshold data is read in parallel one by one from the first addresses of the first to first to fourth memories 100a to 100d. Here, it is assumed that the addresses at which the threshold data of the first to first to fourth memories 100a to 100d are stored all match. That is, it is assumed that threshold data is stored in the addresses 0000h to 1000h of the first to first to fourth memories 100a to 100d. Accordingly, a11, a31, a51, and a71 are stored in each head address. If these are read in parallel, threshold data having the same contents as the head threshold set shown in FIG. 7 can be read. it can. Similarly, in the first to first to fourth memories 100a to 100d, the threshold value data of each address is sequentially read in parallel one by one while incrementing the address value from 0000h by (0010h). A threshold set similar to the storage configuration can be read out in the same order. Note that a storage area of one memory may be divided into four as long as the memory can be accessed in parallel.

  In the first embodiment, the image processing unit 11 is mainly configured by hardware. However, the resolution conversion unit 103, the color conversion unit 104, the threshold data distribution unit 105, and the like are realized by software. It is good also as a structure. Further, when processing is performed in a dot-sequential manner or when processing is performed using a plurality of CPUs, each processing of the first to fourth dither processing units 106 to 109 may be realized by software.

  In the first embodiment, the N-valued data generation process is performed for each of the same regions as the dither matrix in the image data. However, the present invention is not limited to this, and the N value is determined for each row of the image data. It is also possible to employ a configuration for performing generation processing of the digitized data. In this case, until N-valued data for all the pixel data of each row is generated, for example, in the storage configuration of FIG. 7, the threshold set stored in the storage area of the first memory 100 at addresses 0000h to 2000h. Are read cyclically and repeatedly in the order of addresses. Then, for the next row of image data, the threshold set stored in the storage area of the addresses 2400h to 4000h of the first memory 100 is read cyclically and repeatedly in the order of addresses. Also for the third and subsequent rows of image data, the threshold set stored in the storage area at addresses 0000h to 2000h and the threshold set stored in the storage area at addresses 2400h to 4000h are alternately read out and N for each pixel data in each row is read. Generate valued data. Accordingly, the same threshold value data is repeatedly read out as in the case where the threshold selection start position is shifted in units of columns. Therefore, a high-speed cache memory or the like is provided in the threshold value data allocation unit 105 to repeatedly read out. By caching the eight threshold sets and repeatedly using them from the cache memory, it is possible to set the number of readings of the eight threshold sets for each row of image data to one.

  In addition, the printing apparatus 1 in the first embodiment is characterized in that image data is devised by storing a dither matrix data in a memory and a reading method, etc., with almost no modification to the existing printing apparatus itself. Since the N-valued data is generated from the printer, it is not necessary to prepare a special printer as the printing unit 13, and an existing inkjet printer can be used as it is. Further, if the print data generation unit 12 and the print unit 13 are separated from the printing apparatus 1 in the above-described embodiment, the function thereof is a general-purpose print instruction terminal such as a PC or a printer server (these correspond to the image processing apparatus), etc. Can also be realized.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to the drawings. 18 to 23 show a second embodiment of a display device, a display program, a display method, an image processing device, an image processing program and an image processing method, and a storage medium storing the program according to the present invention. It is.
First, a configuration of a display device according to a second embodiment of the present invention will be described with reference to FIG. FIG. 18 is a block diagram showing a configuration of the display device 3 according to the second embodiment of the present invention.

  As shown in FIG. 18, the display device 3 includes an image data acquisition unit 10 ′ that acquires M value (M ≧ 3) image data from an external device and the like, and performs resolution conversion, color conversion on the acquired image data. An image processing unit 11 ′ that performs various image processing such as N-value processing using conversion and dithering to convert M-value image data into N-value image data; and display data based on the converted image data The display data generation unit 14 to be generated and the display unit 15 that executes display processing based on the display data are included. Note that the image processing unit 11 ′ has substantially the same configuration only by partially changing the image processing unit 11 in the first embodiment. Therefore, the same reference numerals are given to components that perform the same or substantially the same processing as the image processing unit 11, and detailed description thereof is omitted.

The image data acquisition unit 10 ′ acquires M-value image data sent from a device (not shown) such as a personal computer (PC) connected to the display device 3 via a network or the like, or not shown. A function of directly reading and acquiring data from a data reading device such as a CD-ROM drive or a DVD drive is provided.
The display data generation unit 14 generates display data (display data) that can be interpreted by the display unit 15 based on the image data converted into N values in the image processing unit 11 ′ (hereinafter referred to as N-valued data). Provides the ability to generate.

The display unit 15 provides a function of displaying an image of the image data acquired by the image data acquisition unit 10 on a liquid crystal display, a CRT display, or the like based on the display data.
Further, a detailed configuration of the image processing unit 11 ′ will be described with reference to FIG. FIG. 19 is a block diagram showing a detailed hardware configuration of the image processing unit 11 ′.

As shown in FIG. 19, the image processing unit 11 ′ includes a first memory 100, a second memory 101, an address generation unit 102, a resolution conversion unit 103, a color conversion unit 104 ′, and a threshold data distribution unit. 105 and the first to third dither processing units 106 to 108.
The resolution conversion unit 103 processes the pixel data input from the second memory 101 so that the resolution of the image data stored in the second memory 101 becomes a resolution corresponding to the display resolution. Then, the processed pixel data is output to the color conversion unit 104. If there is no need to convert the resolution, the pixel data is output to the color conversion unit 104 without being processed.

  When the pixel data input from the resolution converter 103 is data in a color space other than RGB such as YIQ, the color converter 104 displays the input pixel data as RGB (for example, standard RGB such as sRGB). (Including conversion to RGB for display) color space data. Then, the converted pixel data of each color is output separately to the dither processing unit corresponding to each color in the first to third dither processing units 106 to 108 for each color. If the pixel data input from the resolution conversion unit 103 is RGB color space data, the pixel data of each color is directly associated with each color in the first to third dither processing units 106 to 108 without performing conversion processing. Output to the dither processing unit.

The threshold data distribution unit 105 sequentially acquires each threshold data included in the threshold set input from the first memory 100 from the address generation unit 102 based on each address of the threshold set and the address of the pixel data of each color. The first to third dither processing units 106 to 108 are assigned to the dither processing units corresponding to the respective colors.
The first dither processing unit 106 corresponds to R of the three colors RGB, and compares the R (Red) pixel data input from the color conversion unit 104 ′ with the corresponding threshold value and compares it. Based on the magnitude relationship, it is determined whether or not to form dots for the pixel data. Based on the determination result, the M-value R pixel data is converted into N-value data to generate N-valued data. Then, the N-value data is output to the display data generation unit 14.

  The second dither processing unit 107 corresponds to G of the three colors RGB, and compares G (Green) pixel data input from the color conversion unit 104 ′ with a corresponding threshold value and compares it. Based on the magnitude relationship, it is determined whether or not to form dots for the pixel data. Then, based on this determination result, the M-value G pixel data is converted into N-value data to generate N-valued data.

The third dither processing unit 108 corresponds to B out of the three colors RGB, and compares the B (Blue) pixel data input from the color conversion unit 104 ′ with the corresponding threshold value and compares it. Whether or not to form dots for the pixel data is determined based on the magnitude relationship. Based on the determination result, the M-value B pixel data is converted into N-value data to generate N-valued data.
Here, the display device 3 has a hardware configuration as shown in FIG. 4 in the same manner as the printing device 1 in the first embodiment.

Furthermore, the flow of the display process of the display device 3 will be described based on FIG. Here, FIG. 20 is a flowchart showing display processing in the display device 3.
As shown in FIG. 20, the display process first proceeds to step S200, where the image data acquisition unit 10 ′ converts the image data into a recording medium such as an external device, a CD-ROM, a DVD-ROM, It is determined whether or not it has been acquired from a storage device 70 such as an HDD. If it is determined that it has been acquired (Yes), the process proceeds to step S202. If not (No), the determination process is repeated until acquisition. .

In step S202, the image data acquisition unit 10 ′ stores the image data acquired in step S200 in the second memory 101 of the image processing unit 11 ′, and the process proceeds to step S204.
In step S204, the CPU 60 transmits an image processing execution command to the image processing unit 11 ′, causes the image processing unit 11 ′ to execute image processing, and proceeds to step S206.

In step S206, the display data generation unit 14 determines whether or not N-valued data has been acquired from the image processing unit 11 ′. If it is determined that it has been acquired (Yes), the process proceeds to step S208. If not (No), the determination process is repeated until acquisition.
When the process proceeds to step S208, the display data generation unit 14 generates display data based on the N-value data acquired in step S206, and the process proceeds to step S210.

In step S210, the display data generation unit 14 determines whether or not the display data for the image data acquired in step S200 is completed. If it is determined that the display data is completed (Yes), the process proceeds to step S212. If not (No), the process proceeds to step S206.
When the process proceeds to step S212, the display data generation unit 14 outputs the completed display data to the display unit 15, and the process proceeds to step S214.
In step S214, the display unit 15 executes display processing based on the display data input from the display data generation unit 14 and ends the processing.

Next, the operation of the present embodiment will be described with reference to FIGS.
Here, FIG. 21A is a diagram showing an example of the threshold data array of the reference dither matrix (9 rows × 8 columns), where (b) is for R, (c) is for G, and (d) is for B. FIG. 10 is a diagram illustrating an example of threshold data arrangement when the selection start position is shifted in units of three rows. FIG. 22 is a diagram showing a storage configuration of the reference dither matrix data in the first memory 100. FIGS. 23A and 23B are diagrams illustrating an example of a method for reading the reference dither matrix data from the first memory 100. FIG.

Here, the dither matrix used in the first to third dither processing units 106 to 108 of the image processing unit 11 ′ will be described. Here, it is assumed that the reference dither matrix of 9 rows × 8 columns (H = 9, W = 8) shown in FIG. Further, the description will be made assuming that the number of colors of the image data is four colors of CMYK.
First, the selection start position of each color of CMYK is determined so that the start position of each color is different from the start position of the other colors. Here, in the 9-row × 8-column reference dither matrix shown in FIG. 21A, the start position is determined to be shifted by H / C (9/3 = 3) rows from the start position of each color.

First, the threshold value of the selection start position for R is set to a11 in the reference dither matrix. Next, the start position for G is a41 at a position shifted by 3 rows from a11. Similarly, the start position for B is a71 at a position shifted by 3 rows from a41.
Here, when the dither matrix of each color is configured by shifting the arrangement of the reference matrix in units of three rows, the dither matrix of each color of R, G, and B has the configuration shown in FIGS. 21B to 21D, respectively. Become.

Next, the reference dither matrix is divided into a plurality of threshold sets by the same method as in the first embodiment.
Specifically, in the reference dither matrix shown in FIG. 21A, threshold values are selected one by one in the row direction from a11, a41, and a71 which are the selection start positions of the respective colors, and a total of 3 for each of the respective colors. A plurality of threshold sets are formed with one threshold set as one threshold set. That is, a threshold set is formed by selecting threshold values in order for each color from a11 to a38 including the R start position, from a41 to a68 including the G start position, and from a71 to a98 including the B start position. . Thus, the reference dither matrix is changed to (a11, a41, a71), (a12, a42, a72), (a13, a43, a73), ..., (a37, a67, a97), (a38, a68, a98). ) 24 threshold sets.

  In this way, the reference dither matrix divided into the 24 threshold sets is converted into a continuous storage area of addresses of the first memory 100 (a continuous storage area of addresses 0000h to 4800h in FIG. 22), as shown in FIG. ) In the order of forming the threshold set. In the example of FIG. 22, each threshold value is 8 bits (FFh), and each threshold set has a size of 8 × 3 = 24 bits (2FFh). Since there are 24 threshold sets, 24 × 24 = 576 bits, and 24 addresses are set for each 24-bit storage area. That is, one address is set for each threshold set.

Hereinafter, it is assumed that the reference dither matrix is stored in the first memory 100 with the configuration shown in FIG.
First, in the image data acquisition unit 10 ′, the display device 3 acquires M-value image data from an external device or the like (“Yes” branch in step S200), and the acquired image data is stored in the image processing unit 11 ′. Store in the second memory 101 (step S202). After storing the image data in the second memory 101, the display device 3 next transmits an image processing start command to the image processing unit 11 ′ to execute the image processing (step S204). The image processing unit 11 ′ may be configured to detect that image data has been stored in the second memory 101 and execute image processing without receiving a command.

When the image processing is executed, the address generation unit 102 generates an address for reading the pixel data of each color of the image data one by one from the common start position in parallel with each color, and issues a data read command for this address 2 outputs to the memory 101 and outputs the generated address to the threshold data distribution unit 105.
Here, it is assumed that the image data acquired by the image data acquisition unit 10 ′ is data in the YIQ color space. Accordingly, pixel data is selected in order from the start position common to the image data of each YIQ value (luminance / color difference) in accordance with the dither matrix size and the threshold data reading method. In this way, three pixel data of each YIQ value are sequentially read from the second memory 101 and output to the resolution conversion unit 103.

  Further, as shown in FIG. 23A, the address generation unit 102 generates an address for sequentially reading out each threshold set stored in the storage area of the addresses 0000h to 4800h one by one in the order of the addresses, A data read command for this address is output to the first memory 100, and the generated address is output to the threshold data distribution unit 105. As a result, the threshold sets are sequentially read from the first memory 100 one by one in the order of the addresses, and are output to the threshold data distribution unit 105.

  Further, when the threshold set (a38, a68, a98) of the address 4800h is read, the address generation unit 102 generates an address for reading the threshold set stored in the storage areas of the addresses 0000h to 4800h. Then, a data read command for this address is output to the first memory 100, and the generated address is output to the threshold data distribution unit 105. That is, the address generation unit 102 sets addresses 0000h to 4800h until image processing using the dither matrix for the image data to be processed is completed, such as 0000h to 4800h → 0000h to 4800h → 0000h to 4800h →. On the other hand, the addresses are generated so that the threshold set is read cyclically and in the order of the addresses.

On the other hand, when the pixel data is input from the second memory 101, the resolution conversion unit 103 reduces or increases the number of pixels according to the number of pixels with respect to the print resolution. Here, assuming that there is no excess or deficiency, the YIQ pixel data is output to the color conversion unit 104 ′ as it is.
When the YIQ pixel data is input from the resolution conversion unit 103, the color conversion unit 104 ′ converts the YIQ pixel data into RGB pixel data. Then, the converted three pixel data of each color of RGB are separately output to the dither processing units corresponding to the respective colors in the first to third dither processing units 106 to 108.
On the other hand, the threshold data distribution unit 105 determines each threshold data included in the threshold set read from the first memory 100 from the size of the reference dither matrix, the number of corresponding colors, the shift amount of the selection start position, and the like. On the basis of the rule, the first to third dither processing units 106 to 108 separately output the dither processing units corresponding to the respective colors.

  Specifically, the threshold set read from the storage area at addresses 0000h to 4800h in the order shown in FIG. 23A is, for example, the address set at address 0000h as shown in FIG. For the threshold set (a11, a41, a71), the threshold data a11 is used for the first dither processing unit 106 for R, the threshold data a41 is used for the second dither processing unit 107 for G, and the threshold data a71 is used for the B. Each of them is assigned to the third dither processing unit 108. That is, for the 24 threshold sets that are read out for the first time, the threshold set starts from the selection start position of each color, and therefore corresponds to the dither processing section of each color according to the positional relationship of (R, G, B). Threshold data to be distributed is distributed. As in the first embodiment, the 24 threshold sets read for the second time are 24 threshold sets read for the third time because of the positional relationship of (G, B, R). , The threshold data corresponding to the dither processing unit of each color is distributed according to the positional relationship of (B, R, G).

On the other hand, when the threshold data is input from the threshold data distribution unit 105 and the R pixel data is input from the color conversion unit 104, the first dither processing unit 106 is based on the input threshold data and pixel data. N-valued data is generated. Then, the generated N-value data is output to the display data generation unit 14.
Similarly to the first dither processing unit 106, the second to fourth dither processing units 107 to 108 also each threshold value data input from the threshold data distribution unit 105 and each color pixel input from the color conversion unit 104. N-ary data is generated based on the data. Then, the generated N-valued data is output to the display data generation unit 14 respectively.
The first to third dither processing units 106 to 108 operate in parallel, generate N-valued data substantially simultaneously, and output it to the display data generation unit 14.

  By performing such processing on the threshold set stored in the storage area from address 0000h to 4800h read out first time, 9 rows × 8 columns of image data corresponding to the size of the dither matrix N-ary data can be generated for the pixel data up to the third row of each color. Similarly, N-ary data is generated for the pixel data up to the sixth row of each color in the image data of 9 rows × 8 columns corresponding to the size of the dither matrix by the second read after the first read. Can do. Similarly, N-valued data is generated for the pixel data up to the 9th row of each color in the image data of 9 rows × 8 columns corresponding to the size of the dither matrix by the third read after the second read. Can do. However, when performing such readout processing, each pixel data is read out in the order of FIG. 6A described in the first embodiment, and the dither matrix of each color is the same as that in the first embodiment. It is assumed that the shift shown in FIG. 6B described in the embodiment is performed.

By repeating the series of processes described above, all pixel data of the image data is converted into N-valued data.
On the other hand, when the N-value data is input from the image processing unit 11 ′, the display data generation unit 14 generates display data based on the N-value data (steps S206 to S208). When the display data for the acquired image data is generated (“Yes” branch in step S210), the display data is output to the display unit 15.
When the display data is input from the display data generation unit 14, the display unit 15 executes display processing based on the display data (step S214). Thereby, the image of the image data is displayed on the liquid crystal display or the like.

  Note that the image processing unit 11 ′ of the display device 3 according to the present embodiment may have a number of rows or columns equal to or greater than the number of colors, similar to the image processing unit 11 of the printing devices 1 and 2 according to the first embodiment. For example, the size of the reference dither matrix is not limited. Further, the threshold data selection start position can be determined not only by shifting in units of rows but also by shifting in units of columns. In addition, as in the configuration shown in FIG. 17 described above, the first memory 100 is physically divided (in this embodiment, divided into three for three colors of RGB), and the other colors are selected from the selection start position of each color. The threshold data up to one color selection start position can be stored separately in three memories, and the threshold data for the threshold set can be sequentially read by simultaneously accessing these three memories.

  As described above, in the present embodiment, the selection start position of the threshold value corresponding to each color of the image data in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit, and selected one by one from the selection start position in the reference dither matrix. A threshold set is formed from the threshold values for each color, and the reference dither matrix is divided into a plurality of threshold sets. The plurality of threshold sets are sequentially stored in the storage area where the addresses of the first memory 100 are consecutive, starting from the threshold set of the selection start position. The reference dither matrix stored in such a storage configuration is read cyclically and repeatedly with respect to the addresses until all pixel data of the image data is converted into N-valued data in ascending order of addresses for each threshold set. . Further, each threshold value data of the read threshold value set is distributed to the corresponding dither processing unit based on a rule determined by the size of the reference dither matrix, the number of colors of the image data, the shift amount of the selection start position, and the like. On the other hand, the pixel data at the position corresponding to the dither matrix is sequentially read out one by one for each color, and after resolution conversion and color conversion, output to the corresponding dither processing units of the first to third dither processing units 106 to 108, respectively. To do.

Then, using the distributed threshold data and the input pixel data, a determination process and an N-value process are performed to generate N-value data.
As a result, only one reference dither matrix needs to be stored in the memory, so that the memory capacity required for the dither matrix can be reduced.
In addition, threshold data is stored in a storage area with continuous addresses in the order of reading and in the form of a threshold set, and this threshold set is cyclically and repeatedly read from the memory in the order of the addresses. Threshold data to be read can be read at high speed.

  In addition, since threshold data can be read at high speed, resolution conversion processing, color conversion processing, and N-valued data generation processing using a dither matrix can be continuously performed on the read pixel data. . Therefore, in these series of processes, the number of accesses to the memory can be greatly reduced, so that the time from the acquisition of image data to the completion of display can be shortened.

  In the second embodiment, the process of storing the reference dither matrix in the first memory 100 corresponds to the reference dither matrix storage means of any one of the forms 33, 38 and 44, and the address generation unit 102 and the threshold data. The threshold value data (threshold set) reading process from the first memory 100 by the allocating unit 105 corresponds to the threshold value reading unit of the form 33 or 34, and the pixel data reading process from the second memory 101 by the address generating unit 102 Corresponds to the pixel value acquisition unit of the form 33, the determination processing unit 106a (to 108a) corresponds to the determination processing unit of any one of the forms 33 to 35, and the N-value conversion unit 106b (to 108b) This corresponds to the N-value conversion means of form 33.

In the second embodiment, the display data generation unit 14 corresponds to a display data generation unit of form 33, and the display unit 15 corresponds to a display unit of form 33.
In the second embodiment, steps S206 to S212 correspond to the display data generation step of form 38 or 44, and step S214 corresponds to the display step of form 38 or 44.

  In the second embodiment, the image processing unit 11 ′ has a hardware-based configuration, but the resolution conversion unit 103, the color conversion unit 104, the threshold data distribution unit 105, and the like are realized by software. It is good also as composition to do. Further, when processing is performed in a dot-sequential manner or when processing is performed using a plurality of processors, each processing of the first to third dither processing units 106 to 108 may be realized by software.

  In the second embodiment, the N-value data generation process is performed for each of the same regions as the dither matrix in the image data. However, the present invention is not limited to this, and the N value is calculated for each row of the image data. It is also possible to employ a configuration for performing generation processing of the digitized data. In this case, until the N-valued data for all the pixel data in each row is generated, for example, in the storage configuration of FIG. 22, the threshold set stored in the storage area of addresses 0000h to 1800h of the first memory 100 Are read cyclically and repeatedly in the order of addresses. Then, for the next row of image data, the threshold set stored in the storage area of the addresses 2B00h to 3000h of the first memory 100 is read cyclically and repeatedly in the order of addresses. Further, for the next row, the threshold set stored in the storage area of the addresses 3300h to 4800h of the first memory 100 is cyclically and repeatedly read in the order of addresses. Also in the fourth and subsequent lines of the image data, the threshold set stored in the storage area at addresses 0000h to 1800h, the threshold set stored in the storage area at addresses 2B00h to 3000h, and addresses 3300h to 4800h are repeated in this order. Read out to generate N-ary data for each pixel data in each row. Accordingly, the same threshold data is repeatedly read out as in the case where the threshold selection start position is shifted in units of columns. Therefore, a high-speed cache memory or the like is provided in the threshold data distribution unit 105 to repeatedly read out the threshold data. By caching the set and repeatedly using it from the cache memory, the threshold set can be read once for each row of image data.

1 is a block diagram showing a configuration of a printing apparatus 1 according to a first embodiment of the present invention. 2 is a block diagram illustrating a detailed hardware configuration of an image processing unit 11. FIG. 3 is a block diagram showing a detailed configuration of a first dither processing unit 106. FIG. 2 is a diagram illustrating a hardware configuration of the printing apparatus 1. FIG. 4 is a flowchart showing a printing process in the printing apparatus 1. (A) is a figure which shows an example of the threshold value data arrangement | sequence of a reference | standard dither matrix (8 rows x 8 columns), (b) is Cy (cyan), (c) is Mg (magenta), (d) is Ye (yellow) and (e) are diagrams showing an example of threshold data arrangement when the selection start position is shifted in units of two rows with respect to Bk (black). 3 is a diagram showing a storage configuration of reference dither matrix data in the first memory 100. FIG. (A) is a figure which shows an example of the selection method of pixel data, (b) is a figure which shows an example of the application method of a dither matrix. (A) And (b) is a figure which shows an example of the reading method of the reference | standard dither matrix data from the 1st memory 100. FIG. FIGS. 7A and 7B are diagrams illustrating an example of another storage configuration of a threshold set in the first memory 100. FIG. (A) is a figure which shows the example of an arrangement | sequence of the reference | standard dither matrix of 16 rows x 12 columns, (b) is a figure which shows an example of the memory structure of the threshold set with respect to the reference | standard dither matrix of (a). (A) is a figure which shows an example of reference | standard dither matrix (8 rows x 8 columns), (b) and (c) are the structures of the dither matrix in the case of 2 colors which shifted the starting position in units of 4 rows. It is a figure which shows an example, (d) is a figure which shows an example of the memory structure of a threshold set with respect to the reference | standard dither matrix of (a), and an example of the read-out method. (A) is a figure which shows an example of a reference | standard dither matrix, (b) and (c) are figures which show the structural example of the dither matrix in the case of 2 colors, (d) is a figure of (a). It is a figure which shows an example of the reading method of the threshold set with respect to a reference | standard dither matrix, and the distribution method of each threshold value data. (A) is a figure which shows an example of the threshold value data arrangement | sequence of a reference | standard dither matrix (8 rows x 8 columns), (b) is Cy (cyan), (c) is Mg (magenta), (d) is Ye. (Yellow), (e) is a diagram showing an example of threshold data arrangement when the selection start position is shifted in units of two columns with respect to Bk (black). 3 is a diagram showing a storage configuration of reference dither matrix data in the first memory 100 and a method for reading a threshold set. FIG. (A) And (b) is a figure which shows an example of the reading method of the reference | standard dither matrix data from the 1st memory 100. FIG. It is a block diagram which shows the modification of the printing apparatus 1 in 1st Embodiment. It is a block diagram which shows the structure of the display apparatus 3 which concerns on the 2nd Embodiment of this invention. It is a block diagram which shows the detailed hardware constitutions of the image process part 11 '. 4 is a flowchart showing display processing in the display device 3. (A) is a figure which shows an example of the threshold value data arrangement | sequence of a reference | standard dither matrix (9 rows x 8 columns), (b) is R, (c) is G, (d) is the selection start position with respect to B. It is a figure which shows the example of a threshold value data arrangement | sequence at the time of shifting by a 3 line unit. 3 is a diagram showing a storage configuration of reference dither matrix data in the first memory 100. FIG. (A) And (b) is a figure which shows an example of the reading method of the reference | standard dither matrix data from the 1st memory 100. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 2 ... Printing apparatus, 3 ... Display apparatus, 10, 10 '... Image data acquisition part, 11, 11' ... Image processing part, 12 ... Print data generation part, 13 ... Printing part, 14 ... Display data generation part, DESCRIPTION OF SYMBOLS 15 ... Display part, 100 ... 1st memory, 101 ... 2nd memory, 102 ... Address generation part, 103 ... Resolution conversion part, 104,104 '... Color conversion part, 105 ... Threshold data distribution part, 106-109 ... First to fourth dither processing units, 106a... Judgment processing unit, 106b.

Claims (16)

A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. A reference dither matrix, and the selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be a position different from the other colors, respectively. The predetermined threshold value is cyclically selected with respect to the reference dither matrix sequentially from the selection start position of each color in the reference dither matrix in the row direction or the column direction, and the selected threshold value and the corresponding pixel value or The M value pixel is determined by sequentially determining whether the dot is on or off according to the magnitude relationship with the value calculated based on the pixel value. The image data composed into a composed image data from the pixel value of the N (M> N ≧ 2) values, a printing apparatus that performs printing based on the image data after the conversion from
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. Reference dither matrix storage means for storing the reference dither matrix divided into threshold sets in a storage area in which addresses are consecutive in order from the threshold set of the selection start position;
In order from the threshold set of the selection start position in the reference dither matrix stored by the reference dither matrix storage means, each threshold set is subjected to the on / off determination process for all pixel values of the image data. Threshold reading means for cyclically and repeatedly reading out the plurality of threshold sets stored in the continuous storage area of the address, as many times as necessary for
Pixel value acquisition means for acquiring pixel values of the respective colors in order from pixel values of acquisition start positions common to the respective colors in the image data;
Using each threshold value of the threshold set sequentially read by the threshold value reading unit and the pixel value of each color acquired by the pixel value acquisition unit, each threshold value and a pixel value of a color corresponding to each of these threshold values Determination processing means for sequentially performing the determination processing for each combination;
N-value conversion means for converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination processing means;
Print data generation means for generating print data based on image data composed of pixel values converted by the N-value conversion means;
And a printing unit that executes a printing process based on the print data generated by the print data generation unit.   The determination processing means uses the same number of determination processing units for each color as the number of colors of the image data to perform the determination processing, and each threshold value of the threshold set read by the threshold value reading means for each color determination process. And a threshold distribution unit that distributes to the corresponding color determination processing unit, and using the determination processing unit for each color, the determination processing for the pixel value of each color is executed in parallel. The printing apparatus according to claim 1.   The printing apparatus according to claim 2, wherein the determination processing in the determination processing unit is executed for each row or column of each color of the image data. The number of rows of the dither matrix is H (H is an integer of 2 or more), the number of columns is W (W is an integer of 2 or more), and the number of colors of the image data is C (C is an integer of 2 or more).
The printing apparatus according to any one of claims 1 to 3, wherein the shift amount of the reading start position is set to H / C or W / C.   The plurality of threshold sets are stored in a storage area that has the same address for each of the predetermined number of threshold sets in a storage area in which the addresses are continuous for each predetermined number of the threshold sets. The printing apparatus according to any one of claims 1 to 4. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from the pixel value of N ≧ 2) values, there printing program for printing processing based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A pixel value acquisition step of acquiring each pixel value of each color in order from the pixel value of the acquisition start position common to each color in the image data;
Using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color acquired in the pixel value acquisition step, the threshold value and the pixel value of the color corresponding to each of these threshold values A determination processing step for sequentially performing the determination processing for each combination;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A print data generation step for generating print data based on the image data composed of the pixel values converted in the N-value conversion step;
A printing program comprising: a program used for causing a computer to execute a process including a printing step for executing a printing process based on the print data generated in the print data generation step. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from N ≧ 2) of pixel values, there printing method for printing based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A pixel value acquisition step of acquiring each pixel value of each color in order from the pixel value of the acquisition start position common to each color in the image data;
Using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color acquired in the pixel value acquisition step, the threshold value and the pixel value of the color corresponding to each of these threshold values A determination processing step for sequentially performing the determination processing for each combination;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A print data generation step for generating print data based on the image data composed of the pixel values converted in the N-value conversion step;
And a printing step that executes a printing process based on the print data generated in the print data generation step.   A computer-readable storage medium storing the printing program according to claim 6. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. A reference dither matrix, and the selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be a position different from the other colors, respectively. The predetermined threshold value is cyclically selected with respect to the reference dither matrix sequentially from the selection start position of each color in the reference dither matrix in the row direction or the column direction, and the selected threshold value and the corresponding pixel value or The M value pixel is determined by sequentially determining whether the dot is on or off according to the magnitude relationship with the value calculated based on the pixel value. The image data composed of an image processing apparatus for converting the formed image data from the pixel value of the N (M> N ≧ 2) values from,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. Reference dither matrix storage means for storing the reference dither matrix divided into threshold sets in a storage area in which addresses are consecutive in order from the threshold set of the selection start position;
In order from the threshold set of the selection start position in the reference dither matrix stored by the reference dither matrix storage means, each threshold set is subjected to the on / off determination process for all pixel values of the image data. Threshold reading means for cyclically and repeatedly reading out the plurality of threshold sets stored in the continuous storage area of the address, as many times as necessary for
Pixel value acquisition means for acquiring pixel values of the respective colors in order from pixel values of acquisition start positions common to the respective colors in the image data;
Using each threshold value of the threshold set sequentially read by the threshold value reading unit and the pixel value of each color acquired by the pixel value acquisition unit, each threshold value and a pixel value of a color corresponding to each of these threshold values Determination processing means for sequentially performing the determination processing for each combination;
An image processing apparatus comprising: an N-value conversion unit configured to convert the pixel value of each color into one of N types based on a determination result of the determination processing unit. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M There the image processing program to be converted in the composed image data from the pixel value of N ≧ 2) values,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A pixel value acquisition step of acquiring each pixel value of each color in order from the pixel value of the acquisition start position common to each color in the image data;
Using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color acquired in the pixel value acquisition step, the threshold value and the pixel value of the color corresponding to each of these threshold values A determination processing step for sequentially performing the determination processing for each combination;
And a program used for causing a computer to execute a process including an N-value conversion step of converting the pixel value of each color into any of N types of numerical values based on the determination result of the determination process step. Image processing program. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M There the image processing method of converting the composed image data from the pixel value of N ≧ 2) values,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A pixel value acquisition step of acquiring each pixel value of each color in order from the pixel value of the acquisition start position common to each color in the image data;
Using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color acquired in the pixel value acquisition step, the threshold value and the pixel value of the color corresponding to each of these threshold values A determination processing step for sequentially performing the determination processing for each combination;
And an N-value conversion step of converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination processing step.   A computer-readable storage medium storing the image processing program according to claim 10. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. A reference dither matrix, and the selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be a position different from the other colors, respectively. The predetermined threshold value is cyclically selected with respect to the reference dither matrix sequentially from the selection start position of each color in the reference dither matrix in the row direction or the column direction, and the selected threshold value and the corresponding pixel value or The M value pixel is determined by sequentially determining whether the dot is on or off according to the magnitude relationship with the value calculated based on the pixel value. The image data composed into a composed image data from the pixel value of the N (M> N ≧ 2) values, a display device that performs display processing based on the image data after the conversion from
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. Reference dither matrix storage means for storing the reference dither matrix divided into threshold sets in a storage area in which addresses are consecutive in order from the threshold set of the selection start position;
In order from the threshold set of the selection start position in the reference dither matrix stored by the reference dither matrix storage means, each threshold set is subjected to the on / off determination process for all pixel values of the image data. Threshold reading means for cyclically and repeatedly reading out the plurality of threshold sets stored in the continuous storage area of the address, as many times as necessary for
Pixel value acquisition means for acquiring pixel values of the respective colors in order from pixel values of acquisition start positions common to the respective colors in the image data;
Using each threshold value of the threshold set sequentially read by the threshold value reading unit and the pixel value of each color acquired by the pixel value acquisition unit, each threshold value and a pixel value of a color corresponding to each of these threshold values Determination processing means for sequentially performing the determination processing for each combination;
N-value conversion means for converting the pixel value of each color into one of N kinds of numerical values based on the determination result of the determination processing means;
Display data generating means for generating display data based on image data composed of pixel values converted by the N-value converting means;
Display means for executing display processing based on the display data generated by the display data generation means. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from N ≧ 2) of pixel values, there display program performs a display process based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A pixel value acquisition step of acquiring each pixel value of each color in order from the pixel value of the acquisition start position common to each color in the image data;
Using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color acquired in the pixel value acquisition step, the threshold value and the pixel value of the color corresponding to each of these threshold values A determination processing step for sequentially performing the determination processing for each combination;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A display data generation step for generating display data based on the image data composed of the pixel values converted in the N-value conversion step;
A display program comprising: a program used for causing a computer to execute a process including a display step of executing a display process based on display data generated in the display data generation step. A configuration in which pixel values of M (M ≧ 3) values are common to each color of image data having a configuration arranged in a two-dimensional matrix, and a predetermined threshold value is less than the size of the image data and arranged in a two-dimensional matrix. The selection start position of the predetermined threshold value of each color in the reference dither matrix is shifted by a predetermined row unit or a predetermined column unit of the reference dither matrix so as to be different from other colors, and each color in the reference dither matrix The predetermined threshold value is cyclically selected with respect to the reference dither matrix in order from the selection start position in the row direction or the column direction, and is calculated based on the selected threshold value and the corresponding pixel value or the pixel value. In accordance with the magnitude relationship with the value to be determined, the dot on / off is sequentially determined, and the image data composed of the M pixel values is represented by N (M Converted to composed image data from N ≧ 2) of pixel values, there display method performs display processing based on the image data after the conversion,
In order from the threshold value of the selection start position of each color to the threshold value immediately before the selection start position of each other color, a set of threshold values each including one predetermined threshold value of each color is set as a threshold value set. From the threshold set of the selection start position in the reference dither matrix of the reference dither matrix storage means in which the reference dither matrix divided into threshold sets is stored in a storage area in which addresses are consecutive in order from the threshold set of the selection start position. In order, each threshold set is stored in the plurality of threshold sets stored in the continuous storage area of the addresses for the number of times necessary to perform the on / off determination process for all the pixel values of the image data. A threshold value reading step that cyclically and repeatedly reads out;
A pixel value acquisition step of acquiring each pixel value of each color in order from the pixel value of the acquisition start position common to each color in the image data;
Using each threshold value of the threshold set sequentially read in the threshold value reading step and the pixel value of each color acquired in the pixel value acquisition step, the threshold value and the pixel value of the color corresponding to each of these threshold values A determination processing step for sequentially performing the determination processing for each combination;
An N-value conversion step of converting the pixel value of each color into one of N types of numerical values based on the determination result of the determination processing step;
A display data generation step for generating display data based on the image data composed of the pixel values converted in the N-value conversion step;
A display step of executing a display process based on the display data generated in the display data generation step.   A computer-readable storage medium storing the display program according to claim 14.

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