Print data editing device, print data editing method, and print data editing program

Abstract

To provide a print data editing device, a print data editing method and a print data editing program which edit print data that can improve both the print quality and the print speed in comparison to a conventional technique.SOLUTION: A control unit of a print data editing device acquires image data (S1), edits print data in which an image included in a column of a print image becomes the same position as an image expressed by a column of an input image or has the maximum matching degree when sliding by a prescribed amount in the sub-scanning direction Y in a case where a plurality of dots constituting the input image are compared with a plurality of dots constituting the print image in a column unit continuously arrayed from the upstream end to the downstream end in the sub-scanning direction, and the maximum value of a plurality of absolute values of prescribed amounts is equal to or greater than 1 dot (S12), and changes image data or print data of change sub dots being at least one or more sub dots in at least one sub line in at least one line in a print portion from ON to OFF (S15).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a print data editing device, a print data editing method, and a print data editing program. [Background technology]

[0002] Conventionally, there is known a printing device that prints on a print medium using a thermal line head equipped with multiple heating elements (see, for example, Patent Document 1). When a printing device is powered by a battery, AC adapter, or other power source, the current that can be simultaneously supplied to the thermal line head is limited by the specifications of the power source. For this reason, conventional printing devices correct the print data according to the number of dots to be printed, and print the print data by dividing it into dots in even and odd positions, thereby suppressing the peak value of the current supplied to the thermal line head. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-168794 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional printing devices are unable to sufficiently raise the temperature of the heating element at the start of printing a ruled line, which can result in blurred lines, making it difficult to achieve both high print quality and high print speed.

[0005] An object of the present invention is to provide a print data editing device, a print data editing method, and a print data editing program for editing print data that can improve both print quality and print speed compared to conventional methods. [Means for solving the problem]

[0006] A print data editing device according to a first aspect of the present invention is a print data editing device that edits the print data used in a printing device that includes a print head having a plurality of elements lined up in a main scanning direction, and a transport unit that moves a print object and the print head relatively in a sub-scanning direction that intersects with the main scanning direction, and that drives the plurality of elements while moving the print head relatively to the print object in the sub-scanning direction in accordance with print data that includes data instructing ON / OFF of each of the plurality of elements, thereby forming an image on the print object for each line corresponding to the plurality of elements lined up in the main scanning direction, and that includes a control unit, and the control unit includes an image data acquisition process that acquires image data that corresponds to the plurality of elements lined up in the main scanning direction, and an editing process that edits the print data corresponding to the image data, and that edits the print data corresponding to the image data, based on the image data, to arrange a plurality of dots that constitute an input image represented by the image data and a plurality of dots that constitute a print image to be printed in accordance with the print data in at least an area between an upstream end on the upstream side and a downstream end on the downstream side in the sub-scanning direction. the print data editing device can execute an editing process to edit the print data such that, when compared in columns, each of which is a plurality of dots lined up consecutively in the sub-scanning direction, the image included in the column of the print image has the greatest degree of match with the image represented by the column of the input image when the image is positioned at the same position as the image represented by the column of the input image or when the image is shifted a predetermined amount in the sub-scanning direction, and the maximum of the absolute values ​​of the predetermined amounts for the plurality of columns is 1 dot or more; and a modification process to change the image data or print data of at least one modified subdot, which is at least one of the subdots, from ON to OFF in at least one subline in at least one of the lines in the print portion, when the dots defined by the plurality of elements are divided into M units in the sub-scanning direction (M is an integer greater than or equal to 2) and the plurality of subdots lined up in the main scanning direction are defined as sub-lines, and the subdots whose print data are ON are defined as a printed portion and the subdots whose print data are OFF or portions outside the print area are defined as a non-printed portion. By executing the editing process, the print data editing device can edit print data that suppresses the peak current of the print head required to print one line.By performing a change process in addition to an edit process, the print data editing device can further reduce the possibility that the peak current supplied to the print head will exceed the maximum current that can be supplied from the power supply while maintaining print quality. By reducing the number of elements that are turned ON in one line, the print data editing device can increase the possibility of increasing print speed compared to conventional methods that do not perform the edit process and change process. Therefore, the print data editing device can edit print data that improves both print quality and print speed compared to conventional methods.

[0007] A print data editing method according to a second aspect of the present invention is a print data editing method executed by a control unit of a print data editing device that edits print data used in a printing device that includes a print head having a plurality of elements lined up in a main scanning direction, and a transport unit that moves a printing object and the print head relatively in a sub-scanning direction that intersects the main scanning direction, and that drives the plurality of elements while moving the print head relatively to the printing object in the sub-scanning direction in accordance with print data that includes data instructing ON / OFF of each of the plurality of elements, thereby forming an image on the printing object for each line corresponding to the plurality of elements lined up in the main scanning direction. The print data editing method includes an image data acquisition process that acquires image data that corresponds to the plurality of elements lined up in the main scanning direction, and an editing process that edits the print data corresponding to the image data, and based on the image data, edits a plurality of dots that constitute an input image represented by the image data and a plurality of dots that constitute a print image to be printed in accordance with the print data from an upstream end on the upstream side to a downstream end on the downstream side in the sub-scanning direction. and a change process for changing the image data or the print data of a change subdot, which is at least one of the subdots, from ON to OFF in at least one of the sublines in at least one of the lines in the print portion, when the dots defined by the elements are divided into M units (M is an integer of 2 or more) in the subscanning direction and the dots defined by the elements are defined as a print unit, and the subdots whose print data are ON are defined as a print portion, and the subdots whose print data are OFF or a portion outside the print area are defined as a non-print portion. The print data editing method according to the second aspect is executed by the control unit of the print data editing device, thereby achieving the same effects as the print data editing device of the first aspect.

[0008] A print data editing program according to a third aspect of the present invention is a print data editing program executed by a control unit of a print data editing device that edits print data used in a printing device that includes a print head having a plurality of elements lined up in a main scanning direction, and a transport unit that moves a printing object and the print head relatively in a sub-scanning direction that intersects with the main scanning direction, and that drives the plurality of elements while moving the print head relatively to the printing object in the sub-scanning direction in accordance with print data that includes data instructing ON / OFF of each of the plurality of elements, thereby forming an image on the printing object for each line corresponding to the plurality of elements lined up in the main scanning direction. The print data editing program includes an image data acquisition process that acquires image data that corresponds to the plurality of elements lined up in the main scanning direction, and an editing process that edits the print data corresponding to the image data, and based on the image data, edits a plurality of dots that constitute an input image represented by the image data and a plurality of dots that constitute a print image to be printed in accordance with the print data by dividing the plurality of dots by a distance between an upstream end on the upstream side and a downstream end on the downstream side in the sub-scanning direction. the print data is edited so that, when compared in units of columns, which are multiple dots that are lined up continuously in the sub-scanning direction at least in part, the image included in the column of the print image has the greatest degree of match when it is positioned at the same position as the image represented by the column of the input image or when it is slid a predetermined amount in the sub-scanning direction, and the maximum value among the absolute values ​​of the multiple predetermined amounts for the multiple columns is 1 dot or more; and instructions to cause the control unit to execute a change process, wherein, when the dot defined by the multiple elements is divided into M units (M is an integer of 2 or more) in the sub-scanning direction, a sub-dot is defined as a printing unit, and multiple sub-dots lined up in the main scanning direction are defined as sub-lines, the sub-dots for which the print data is ON are defined as printing portions, and the sub-dots for which the print data is OFF or portions outside the printing area are defined as non-printing portions, the image data or the print data of change sub-dots, which are at least one or more of the sub-dots, are changed from ON to OFF in at least one sub-line in at least one of the lines in the printing portion.The print data editing program according to the third aspect is executed by the control unit of the print data editing device, thereby achieving the same effects as those of the print data editing device according to the first aspect. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is an explanatory diagram of a printing device 1. [Figure 2] 2 is a block diagram showing the electrical configuration of the printing device 1. FIG. [Figure 3] 1 is a flowchart of a printing process executed by the printing device 1. [Figure 4] FIG. 10 is an explanatory diagram of an input image G of a specific example. [Figure 5] FIG. 10 is an explanatory diagram of a process for generating a high-resolution image. [Figure 6] FIG. 10 is an explanatory diagram of a method for setting a target image. [Figure 7] 10 is a flowchart of a comparison condition acquisition process executed in the printing process. [Figure 8] FIG. 10 is an explanatory diagram of an editing method. [Figure 9] 10 is a flowchart of a change process executed in the printing process. [Figure 10] FIG. 10 is an explanatory diagram of a change process in a specific example in which an edit process is not executed. [Figure 11] FIG. [Figure 12] FIG. 10 is an explanatory diagram of a change process in a specific example in which an edit process is executed. [Figure 13] FIG. 10 is an explanatory diagram comparing images before and after performing editing and changing processes on a ruled line extending in the main scanning direction, under the condition that the absolute value of the difference in a predetermined amount between any two partial images adjacent in the main scanning direction X is 150 μm. [Figure 14] FIG. 10 is an explanatory diagram of a process for generating a composite image. [Figure 15] FIG. 10 is an explanatory diagram of a process for generating a composite image. [Figure 16] FIG. 10 is an explanatory diagram of a division process. [Figure 17] FIG. 10 is an explanatory diagram of a division process. [Figure 18] FIG. 10 is an explanatory diagram of a first condition, a second condition, and a third condition that an editing method satisfies. [Figure 19] 10 is a flowchart of a change process executed in a printing process according to a modified example. [Figure 20] FIG. 10 is an explanatory diagram comparing images before and after performing editing and change processing on a ruled line extending in the main scanning direction under comparative example conditions in which the absolute value of the difference in a predetermined amount between any two partial images adjacent in the main scanning direction X is 300 μm. DETAILED DESCRIPTION OF THE INVENTION

[0010] A printing device 1 according to one embodiment of the present invention will be described with reference to the drawings. The drawings are used to explain technical features that can be adopted by the present invention. In other words, the configuration and control of the device shown in the drawings are merely illustrative examples and are not intended to be limiting.

[0011] As shown in Figure 1, the printing device 1 is a thermal printer capable of printing characters (objects such as letters, symbols, numbers, and figures) on a printing object F. The printing object F is not limited to a specific medium, but may be, for example, a sheet or tape, and in this embodiment is cut paper that is a thermal recording medium. The printing device 1 functions as a printing data editing device that edits printing data.

[0012] The printing device 1 comprises a case 2, an input unit 3, a communication unit 4, a transport unit 5, and a print head 6. The case 2 is rectangular and longer left-to-right than front-to-back and up-to-down. The case 2 houses the transport unit 5 and the print head 6. The case 2 detachably houses a power supply 10 (shown in FIG. 2). The power supply 10 supplies power to the printing device 1. An insertion slot 21 is formed on the top surface of the case 2, and an ejection slot 22 is formed on the front surface of the case 2. The insertion slot 21 and the ejection slot 22 are each formed in a rectangular shape that is long in the left-to-right direction. The printing object F is inserted into the printing device 1 through the insertion slot 21 and ejected from the printing device 1 through the ejection slot 22. The input unit 3 is located near the left end of the top surface of the case 2. The input unit 3 includes multiple push buttons. The communication unit 4 is a USB jack located on the right side of the case 2. A USB cable connector can be connected to the communication unit 4.

[0013] The transport unit 5 includes a motor 51 and a roller 52 shown in FIG. 2. The roller 52 is roller-shaped and has an axis extending in the left-right direction as its center, and is provided diagonally upward and forward within the case 2. The motor 51 rotates the roller 52. The transport unit 5 transports the print object F in the transport direction TR by the rotation of the roller 52, thereby moving the print object F relative to the print head 6. The transport direction TR is a direction perpendicular to the left-right direction, and in this embodiment, extends diagonally upward and backward and diagonally downward and forward. Hereinafter, the diagonally upward and backward in the transport direction TR will be referred to as the upstream side, and the diagonally downward and forward side will be referred to as the downstream side.

[0014] The print head 6 is provided below the roller 52. The print head 6 is a line head and includes a plurality of elements 61 and a driver IC 62 shown in FIG. 2. In this embodiment, each of the plurality of elements 61 is a heat-generating element that generates heat when energized. The plurality of elements 61 come into contact with the print target F that is pressed downward by the roller 52, and generate heat, thereby printing on the print target F. The driver IC 62 is configured to selectively energize the plurality of elements 61 to generate heat.

[0015] The electrical configuration of the printing device 1 will be described with reference to FIG. 2. The printing device 1 includes a CPU 7, RAM 8, a storage unit 9, a communication unit 4, an input unit 3, a transport unit 5, and a print head 6. The transport unit 5 includes a motor 51 and a roller 52. The print head 6 includes a driver IC 62 and multiple elements 61. The CPU 7 controls the printing device 1. The CPU 7 is electrically connected to the RAM 8, the storage unit 9, the communication unit 4, the input unit 3, the motor 51, and the driver IC 62. The RAM 8 stores temporary data such as various variables. The storage unit 9 stores programs executed by the CPU 7 to control the printing device 1, print data, and various setting information. The communication unit 4 is a controller for communicating with an external device W via a USB cable. The external device W is, for example, a known information processing device such as a PC, tablet PC, or smartphone.

[0016] The printing operation of the printing device 1 will be described. The printing device 1 selectively energizes the multiple elements 61 of the print head 6 in accordance with print data. Thermal energy is applied to portions of the printing object F that come into contact with the energized multiple elements 61. As a result, the printing device 1 forms pixel rows aligned in the main scanning direction X corresponding to the arrangement of the multiple elements 61. The printing device 1 intermittently energizes the multiple elements 61 multiple times while rotating the roller 52 using the motor 51 to transport the printing object downstream in the transport direction TR. As a result, multiple lines are formed on the printing object F, arranged in a direction perpendicular to the arrangement of pixels in one line of an image. The multiple lines create shades on the printing object F depending on whether or not each pixel is formed, forming a printed image. The above operation is referred to as the "printing operation."

[0017] In the following description, the direction in which the multiple elements 61 are arranged is referred to as the "main scanning direction X," and a printing unit corresponding to one pixel row arranged in the main scanning direction X is referred to as a "line." The arrangement direction of the multiple lines is referred to as the "sub-scanning direction Y." The sub-scanning direction Y is defined by the transport direction TR. A printing unit corresponding to each of the multiple elements 61 is referred to as a "pixel" or a "dot." A printing unit obtained by dividing a "dot" into multiple parts in the sub-scanning direction Y is referred to as a "sub-dot." A printing unit corresponding to a sub-dot row arranged in the main scanning direction X is referred to as a "sub-line."

[0018] With reference to FIGS. 3 to 18, the printing process of the printing device 1 will be described using a specific example of printing the input image G shown in FIG. 4. As shown in FIG. 4, the input image G represents an invoice in English and is printed on A4-sized thermal paper. The left-right direction of the input image G corresponds to the main scanning direction X, and the up-down direction of the input image G corresponds to the sub-scanning direction Y. The left side of the input image G corresponds to one side X1 of the main scanning direction, and the right side of the input image G corresponds to the other side X2 of the main scanning direction. The top of the input image G corresponds to the downstream side Y1 of the sub-scanning direction, and the bottom of the input image G corresponds to the upstream side Y2 of the sub-scanning direction. The input image G includes multiple ruled lines G1 to G4 extending in the main scanning direction X, multiple ruled lines G5 and G6 extending in the sub-scanning direction Y, a barcode G7, and character portions T1 to T7. In FIGS. 6, 8, 14, and 15, each of the character portions T1 to T7 is schematically represented by a shaded rectangle. Within the printing range defined by the print data, the portion made up of subdots whose print data is ON is called the "printed portion," and the portion made up of subdots whose print data is OFF is called the "non-printed portion." In this embodiment, the portion outside the printing area is also included in the non-printed portion.

[0019] The user selects the input image G to be printed, specifies at least one of a characteristic portion, a target portion, and a non-target portion as necessary, and then inputs a start instruction via the input unit 3. The characteristic portion is a portion of the input image G that is distinctive, such as a barcode, and to which it is not desirable to apply the editing and conversion processes described below. For example, a portion P4 including a barcode G7 is identified as the characteristic portion based on information input or pattern matching. The target portion is a portion of the input image G to which the user has instructed to apply the editing and conversion processes. For example, a portion P1 including a ruled line G1, a portion P2 including a ruled line G2, and a portion P3 including a ruled line G3 are specified. The non-target portion is a portion of the input image G to which the user has instructed not to apply the editing and conversion processes. For example, a portion P4 is specified as the non-target portion.

[0020] When the CPU 7 detects a start instruction, it loads a print data editing program for executing the printing process from the storage unit 9 into the RAM 8. The CPU 7 executes the printing process, which includes the following steps, in accordance with the instructions contained in the loaded print data editing program. Various data obtained during the printing process is stored in the storage unit 9 as appropriate. Hereinafter, each step is abbreviated as S. In Figures 5, 10 to 12, and 16 to 18, a portion of the multiple subdots corresponding to the print data are shown in a matrix. Subdots with print data ON are indicated by dot shading, and subdots with print data OFF are indicated by white. The left-right and up-down directions correspond to the main scanning direction X and the sub-scanning direction Y, respectively. Column names, represented by numbers, indicate identification numbers assigned to each of the multiple elements 61, starting from one side X1 in the main scanning direction. Row names, represented by numbers, indicate the identification numbers of the lines printed by the elements 61. The printing device 1 forms an image on the printing target F in ascending order of line number.

[0021] As shown in FIG. 3, the CPU 7 acquires image data representing the input image G (S1). The image data is data associated with the plurality of elements 61 arranged in the main scanning direction X. The CPU 7 acquires, for example, image data generated by the external device W and having a higher resolution than the resolution in the sub-scanning direction Y defined by the plurality of elements 61 from the external device W via the communication unit 4. The CPU 7 may acquire image data generated by the external device W and having a resolution equal to or lower than the resolution in the sub-scanning direction Y defined by the plurality of elements 61, or may acquire image data stored in the storage unit 9, or may acquire image data edited by operating the input unit 3.

[0022] The CPU 7 determines whether to perform high-resolution processing (S2). The high-resolution processing is a process for increasing the resolution in the sub-scanning direction Y by dividing each line in the sub-scanning direction Y for the image data representing the input image G acquired in S1. For example, the CPU 7 does not perform the high-resolution processing if the image data acquired in S1 is image data generated by the external device W and has a higher resolution in the sub-scanning direction Y than the resolution in the sub-scanning direction Y defined by the multiple elements 61. For example, the CPU 7 performs the high-resolution processing if the image data acquired in S1 is image data having a resolution equal to or lower than the resolution in the sub-scanning direction Y defined by the multiple elements 61.

[0023] If high-resolution processing is to be performed (S2: YES), the CPU 7 performs high-resolution processing on the image data by dividing each line in the sub-scanning direction Y to increase the resolution in the sub-scanning direction Y (S3). As shown in FIG. 5, the CPU 7, for example, divides each line into three equal parts in the sub-scanning direction Y. The number of divisions into each line may be changed as appropriate. By equally dividing each line in the sub-scanning direction Y, the start timing of each sub-dot is set to an equal cycle. Three consecutive sub-dots in the sub-scanning direction Y correspond to one dot. The CPU 7 designates all sub-dots generated by dividing a dot in the printing portion as the printing portion. The CPU 7 designates all sub-dots generated by dividing one dot in the non-printing portion as the non-printing portion. If high-resolution processing is not to be performed (S2: NO), the CPU 7 does not perform any processing on the input image G acquired in S1 (S4).

[0024] After S3 or S4, the CPU 7 determines whether a characteristic portion is set in the input image G acquired in S1 (S5). If the characteristic portion P4 is set in the input image G (S5: YES), the CPU 7 sets a non-characteristic portion H in the target image to be edited (S6), as shown in FIG. 6. The non-characteristic portion H is the high-resolution image of S3 or the input image G of S4 excluding the characteristic portion P4. By the processing of S6, if a specific pattern is included in the input image G, the target image is set so that editing processing is not performed on the specific pattern.

[0025] If no characteristic parts have been set (S5: NO), the CPU 7 determines whether or not target parts have been set in the input image G acquired in S1 (S7). If target parts P1 to P3 have been set in the input image G (S7: YES), the CPU 7 sets the target parts P1 to P3 in the target image (S8). If the target parts P1 to P3 have been set in the input image G by the processing of S8, the target image is set so that editing processing is performed on the target parts P1 to P3 and editing processing is not performed on non-target parts excluding the target parts P1 to P3.

[0026] If a non-target portion P4 is set in the input image G (S7: YES), the CPU 7 sets a portion H of the high-resolution image of S3 or the input image G of S4 excluding the non-target portion P4 as the target portion in the target image (S8). If a non-target portion P4 is set in the input image G by the processing of S8, the target image is set so that editing processing is not performed on the non-target portion P4, but on the target portion H excluding the non-target portion P4. If a target portion is not set in the input image G (S7: NO), the CPU 7 sets the high-resolution image of S3 or the input image G of S4 as the target image (S9).

[0027] After S6, S8, or S9, the CPU 7 performs a comparison condition acquisition process (S10). The comparison condition acquisition process is a process for acquiring conditions used to determine whether to perform editing processing. In this embodiment, the printing speed when editing processing is performed and the printing speed when editing processing is not performed are acquired as conditions used to determine whether to perform editing processing. The editing process is a process performed to reduce the peak number of energized elements 61 (hereinafter referred to as the "number of on dots"), and distributes multiple sub-dots on the same line across multiple lines by moving them in the sub-scanning direction Y according to a predetermined rule.

[0028] As shown in FIG. 7, in the comparison condition acquisition process, the CPU 7 acquires the print speed when no editing process is performed (S31). If there is a line where the number of ON dots is greater than a threshold, the CPU 7 divides the line into multiple blocks of multiple elements 61. The printing device 1 prints one line of an image by energizing the multiple elements 61 for each divided block multiple times. Printing performed in this manner is called "divided printing." Depending on the number of lines and blocks to be divided and printed, the print speed will be slower than when no dividing printing is performed. The CPU 7 acquires the print speed when no editing process is performed, taking into account the number of lines and blocks to be divided and printed.

[0029] The CPU 7 acquires the editing method to be used in the current editing process from among multiple editing methods (S32). The editing method may be specified by the user or selected by the CPU 7 based on the type, size, etc. of the input image G. The printing device 1 of this embodiment can select one of six editing methods. Referring to FIG. 8, an example in which the six editing methods are applied to the target portion H will be described. Each of the first through fourth editing methods divides the target image into multiple partial images by columns and edits the print data by sliding each of the multiple partial images in the sub-scanning direction Y by a predetermined amount corresponding to the partial image. More specifically, the CPU 7 divides the target image into a number of rectangles, J (a natural number), elongated in the sub-scanning direction Y. Then, relative to the initial position indicated by the dotted line PM, each rectangle is moved in the sub-scanning direction Y as a partial image within a range that satisfies editing conditions, including the following three conditions: J may be set as appropriate and is 10 in this embodiment. When the target image includes ruled lines whose longitudinal direction is the sub-scanning direction Y, such as ruled lines G5 and G6 in the input image G, the CPU 7 may adjust the lengths of the rectangles in the main scanning direction X so that the ruled lines whose longitudinal direction is the sub-scanning direction Y are not positioned on the boundaries of the rectangles. The lengths of the rectangles in the sub-scanning direction Y may be the same as or different from each other.

[0030] The first condition is that when the target image and the printed image are compared in units of columns, which are multiple dots arranged continuously in the sub-scanning direction Y, from the upstream end DE on the upstream side Y2 in the sub-scanning direction to the downstream end UE on the downstream side Y1 in the sub-scanning direction, the image included in the column of the printed image will have the highest degree of match when it is positioned at the same position as the image represented by the column of the target image or when it is shifted a predetermined amount in the sub-scanning direction Y, and the maximum absolute value of the multiple predetermined amounts for the multiple columns is 1 dot or more. The second condition is that the absolute value of the difference in the predetermined amounts between any two columns adjacent in the main scanning direction X is 1 dot or less. The multiple predetermined amounts for the multiple columns are predetermined amounts for each column. The degree of match is the number of sub-dots whose ON / OFF values ​​match when comparing the ON / OFF values ​​of sub-dots included in columns located at the same position in the main scanning direction X between the target image and the printed image, divided by the number of sub-dots included in the column. The degree of match is a value between 0 and 1. In this embodiment, the predetermined amount when sliding toward the downstream side Y1 in the sub-scanning direction is expressed by a positive value, and the predetermined amount when sliding toward the upstream side Y2 in the sub-scanning direction is expressed by a negative value. The third condition is: Of the absolute values ​​of the differences between the predetermined amounts between any two rows, the absolute values ​​of one or more of the differences are values ​​less than one dot, and are represented by subdots obtained by dividing a dot in the sub-scanning direction Y into a plurality of subdots.

[0031] For example, when comparing the ON / OFF values ​​of subdots included in columns at the same position in the main scanning direction X between input image J1 and printed image J2 in FIG. 18, the degree of match reaches the maximum value of 1 when columns 1 to 7 are slid in the secondary scanning direction Y by -3 subdots, -2 subdots, -2 subdots, -1 subdot, -1 subdot, 0 subdot, and 0 subdot. In this specific example, since 3 subdots correspond to 1 dot, input image J1 and printed image J2 satisfy the first condition. The absolute value of the difference in a predetermined amount between any two adjacent columns in the main scanning direction X is 1 subdot or 0 subdot, and input image J1 and printed image J2 satisfy the second and third conditions. On the other hand, when comparing columns 1 through 7 of the input image J1 with the print image J4, which has been edited and then modified (described later) to change the print data of some of the printed areas from ON to OFF, starting from one side X1 in the main scanning direction, the predetermined amount is the same, but the degree of match corresponding to the elements 61 with identification numbers 2 through 6 is 14 / 15, which is less than 1. Since the predetermined amount for each column when comparing the input image J1 with the print image J4 is the same as the predetermined amount for each column when comparing the input image J1 with the print image J2, the input image J1 and the print image J4 satisfy the first, second, and third conditions. The length of one dot in the sub-scanning direction Y varies depending on the resolution of the print image. The length of one dot in the sub-scanning direction Y depends on the resolution of the elements 61, but falls within a range of approximately 20 μm to 170 μm. Therefore, the second condition may be that the absolute value of the difference in the predetermined amount between any two adjacent columns in the main scanning direction X is 150 μm or less. The CPU 7 of this embodiment further edits the target image so that the absolute value of the predetermined amount is minimized in the center in the main scanning direction X. Portions corresponding to the continuous print portions in the input image J1 are also continuous in the print images J2 and J4.

[0032] The first editing method is a method of editing the target image such that, when the predetermined amount when sliding toward the upstream side Y2 in the sub-scanning direction is a negative value and the predetermined amount when sliding toward the downstream side Y1 in the sub-scanning direction is a positive value, the predetermined amount in the main scanning direction X becomes larger in the direction 90 degrees clockwise from the downstream side Y1 in the sub-scanning direction, i.e., the further toward the other side X2 in the main scanning direction. More specifically, as shown in Fig. 8, when applying the first editing method to the target image H, the CPU 7 changes the predetermined amounts E1 to E10 of the first to tenth rectangular partial images from one side X1 in the main scanning direction to -5 subdots, -4 subdots, -3 subdots, -2 subdots, - The edited image H1 is generated by setting the number of subdots to 1, 0, 1, 2, 3, and 4. In the first editing method, the difference in the predetermined amount between any two adjacent rows is 0 or 1 subdot, and is a value less than 1 dot, represented by subdots obtained by dividing a dot into multiple subdots in the sub-scanning direction Y. The maximum absolute value of the predetermined amount is 5 subdots, which is 1 dot or more.

[0033] Similarly, the second editing method is a method of editing the target image such that, when the predetermined amount when sliding toward the upstream side Y2 in the sub-scanning direction Y is a negative value and the predetermined amount when sliding toward the downstream side Y1 in the sub-scanning direction Y is a positive value, the predetermined amount in the main scanning direction X becomes smaller as it moves 90 degrees clockwise from the downstream side Y1 in the sub-scanning direction Y. More specifically, when applying the second editing method to the target image H, the CPU 7 sets the predetermined amounts E1 to E10 of the first to tenth rectangular partial images from one side X1 in the main scanning direction to 5 subdots, 4 subdots, 3 subdots, 2 subdots, 1 subdot, 0 subdot, -1 subdot, -2 subdot, -3 subdot, and -4 subdot, respectively, to generate an edited image H2.

[0034] The third editing method is a method of editing a target image so that there is only one extremum of a predetermined amount in the main scanning direction X. More specifically, when applying the third editing method to target image H, CPU 7 sets the predetermined amounts E1 to E10 of the first to tenth rectangular partial images from one side X1 in the main scanning direction to -4 subdots, -3 subdots, -2 subdots, -1 subdots, 0 subdots, -1 subdots, -2 subdots, -3 subdots, -4 subdots, and -5 subdots, respectively, to generate edited image H3. The extremum in the third editing method is 0 subdots, which corresponds to the fifth partial image from the left.

[0035] The fourth editing method is a method of editing a target image so that there are two or more extrema of a predetermined amount in the main scanning direction X. More specifically, when applying the fourth editing method to target image H, CPU 7 sets the predetermined amounts of the first to tenth rectangular partial images from one side X1 in the main scanning direction to -3 subdots, -2 subdots, -1 subdots, 0 subdots, 0 subdots, -1 subdots, -2 subdots, -3 subdots, -2 subdots, and -1 subdots, respectively, to generate edited image H4. The extrema in the fourth editing method are 0 subdots corresponding to the fourth and fifth partial images from the left, and -3 subdots corresponding to the eighth partial image from the left.

[0036] The fifth editing method is an editing method in which the target image is rotated clockwise by a predetermined angle around a reference point. The sixth editing method is an editing method in which the target image is rotated counterclockwise by a predetermined angle around a reference point. The reference point in this embodiment is set in consideration of the minimum absolute value of the predetermined amount at the center in the main scanning direction X, and is, for example, the center of the target image. The predetermined angle may be set appropriately depending on the size of the printing object F, the target image, etc. The predetermined angle is, for example, a value between 0 and 10 degrees, and is preferably 1The predetermined angle is preferably a value of 0.5 degrees or less, and more preferably a value of 0.5 degrees or less. When the CPU 7 applies the fifth editing method to the target image H with a predetermined angle of 1 degree, it generates an edited image H5. When the CPU 7 applies the sixth editing method to the target image H with a predetermined angle of 1 degree, it generates an edited image H6. When the target image is divided into J rectangular partial images elongated in the sub-scanning direction Y as in the first to fourth editing methods, edited image H5 to which the fifth editing method is applied and edited image H6 to which the sixth editing method is applied satisfy the first, second, and third conditions when the predetermined amounts E1 to E10 of each partial image are compared. When the fifth or sixth editing method is applied, the condition that the degree of match with the print image is maximized when the target image is rotated a predetermined angle around a reference, and the amount of movement of the portion furthest from the reference is greater than one dot, is satisfied.

[0037] The CPU 7 generates an edited image by editing the target image using the editing method acquired in S32 (S33). The CPU 7 acquires the print speed when printing the edited image generated in S33 (S34). The CPU 7 acquires the print speed when performing the edit process, taking into account the number of lines to be divided and printed and the number of blocks. The CPU 7 then ends the comparison condition process and returns the process to the print process of FIG. 3.

[0038] After S10, the CPU 7 determines whether to execute editing processing on the target image (S11). The criteria for determining whether to execute editing processing on the target image may be set as appropriate. A user-selected criterion from among multiple criteria may be used, or the CPU 7 may select a criterion based on the type, size, etc., of the input image G. For example, the CPU 7 may determine to execute editing processing if the target image includes a predetermined number of ruled lines extending a predetermined length or more in the main scanning direction X. The predetermined length and the predetermined number may be set as appropriate. For example, if the predetermined length is set to half the length of the target image in the main scanning direction X and the predetermined number is 3, the target image H includes ruled lines G1 to G3 that are longer than half the length of the target image in the main scanning direction X, and therefore it is determined that editing processing is to be executed. In another example, the CPU 7 may execute editing processing if the image data includes a line for which the peak current required by the print head 6 is greater than a threshold value relative to the maximum current that the power supply 10 can output (S11: YES) (S12). In another example, the CPU 7 may execute the edit process if the print speed is faster when printing is performed based on print data edited in the edit process than when the print data is not edited in the edit process (S12). 3 If the print speed acquired in S4 is faster than the print speed acquired in S31, the editing process may be executed. If the peak number of ON dots in the edited image is reduced compared to the target image, the print speed acquired in S34 may be faster than the print speed acquired in S31.

[0039] If editing processing is to be performed (S11: YES), the CPU 7 edits the target image using the editing method acquired in S32 (S12). As shown in FIG. 8, for example, if the first editing method is applied to the target image H, the CPU 7 edits the print data to generate data representing an edited image H1. If editing processing is performed on the target image set in S9, the CPU 7 performs editing processing on the entire input image G or the entire high-resolution image. If editing processing is performed on the target image set in S6 or S8, the CPU 7 performs editing processing on a portion of the input image G or a portion of the high-resolution image. If target portions P1 to P3 are set as the target image in S8, the CPU 7 performs editing processing on only a portion of the input image G or the high-resolution image in the sub-scanning direction Y. If editing processing is not to be performed (S11: NO), the CPU 7 generates print data from the image data without performing editing processing on the target image (S13).

[0040] After S12 or S13, the CPU 7 determines whether to perform modification processing (S14). Modification processing is processing that modifies the print data so as to reduce the number of ON dots in one line. The criteria for determining whether to perform modification processing may be set in advance by the user, or may be determined automatically by the CPU 7 based on the type, size, print speed, print quality, number of ON dots, etc. of the print data. If modification processing is not to be performed (S14: NO), the CPU 7 does not perform modification processing on the target image of S12 or S13 (S16). If modification processing is to be performed (S14: YES), the CPU 7 performs modification processing on the target image of S12 or S13 (S15). In the change process, the CPU 7 defines a printing unit obtained by dividing a dot defined by a plurality of elements 61 into M pieces (M is an integer of 2 or more) in the sub-scanning direction Y as a sub-dot, defines a plurality of sub-dots arranged in the main scanning direction X as a sub-line, defines sub-dots for which the print data is ON as a printed portion, and defines sub-dots for which the print data is OFF or portions outside the printing area as a non-printed portion, and changes the image data or print data of at least one or more changed sub-dots from ON to OFF in all sub-lines in at least one line within the printed portion.

[0041] The modification process will be described using the diagrams of FIGS. 10 to 12, which schematically show portions of a print image represented by print data. As shown in FIG. 9, in the modification process, the CPU 7 acquires outline conditions (S40). The printing device 1 of this embodiment allows the user to specify whether to modify the print data for the outline portion of a print portion formed by subdots whose print data is ON. Specifically, the CPU 7 defines the range of the outline portion for which modification process is not performed using variables U, D, L, and R. Variable U is a variable that sets the range of the outline portion set on the downstream side Y1 of a continuous print portion in the sub-scanning direction. Variable D is a variable that sets the range of the outline portion set on the upstream side Y2 of a continuous print portion in the sub-scanning direction. Variable L is a variable that sets the range of the outline portion set on one side X1 of a continuous print portion in the main scanning direction. Variable R is a variable that sets the range of the outline portion set on the other side X2 of a continuous print portion in the main scanning direction. The variables U, D, L, and R may each be an integer equal to or greater than 0, and may be the same or different. The variables U, D, L, and R may each be set by the user, or may be automatically set depending on the type of target image, etc. In this embodiment, the variables U, D, L, and R are 2, 1, 1, and 1, respectively.

[0042] The CPU 7 acquires one subdot from among the multiple subdots included in the print data as a subdot of interest (S41). The CPU 7 acquires the subdot of interest, for example, from left to right and from top to bottom of the target image. The CPU 7 determines whether the subdot of interest is a printed portion based on the print data of the subdot of interest acquired in S41 (S42). If the print data corresponding to the subdot of interest is OFF (S42: NO), the CPU 7 leaves the print data of the subdot of interest OFF (S47), and determines whether all subdots included in the print data have been acquired as subdots of interest in the process of S41 (S48). If there are subdots that have not been acquired in the process of S41 (S48: NO), the CPU 7 returns to S41 and acquires the next subdot of interest in the acquisition order (S41).

[0043] As shown in FIG. 10, the print data corresponding to the target subdot TS1, indicated by diagonal shading, is ON (S42: YES), so the CPU 7 determines whether the downstream reference portion is a non-print portion (S43). The downstream reference portion is one or more subdots located downstream Y1 in the sub-scanning direction from the target subdot. In this embodiment, the downstream reference portion is the subdot U-th from the target subdot TS1 downstream Y1 in the sub-scanning direction. The downstream reference portion for the target subdot TS1 is subdot UR1, indicated by diagonal lattice shading, and the print data for subdot UR1 is OFF (S43: YES). In this case, the CPU 7 sets the target subdot TS1 as a contour subdot that constitutes the contour portion, leaves the print data for the target subdot TS1 ON (S46), and proceeds to the process of S48. In this way, when a target subdot, which is one of the multiple subdots, is in the print portion (S42: YES), the CPU 7 sets the subdot that is located Uth (U is any integer equal to or greater than 0) downstream Y1 of the target subdot TS1 in the sub-scanning direction Y as the reference subdot. When the reference subdot is in the non-print portion (S43: YES), the CPU 7 sets the target subdot as a contour subdot, and leaves the image data or print data of the contour subdot ON (S46).

[0044] If the target subdot TS2 indicated by diagonal shading is acquired (S41, S42: YES), the downstream reference portion for the target subdot TS2 is the subdot UR2 indicated by diagonal lattice shading, and the print data for the subdot UR2 is ON (S43: NO). In this case, the CPU 7 determines whether at least any of the surrounding reference portions is a non-printing portion (S44). The surrounding reference portion is one or more subdots located around the target subdot. The surrounding reference portion may include, for example, the Lth subdot on one side X1 of the target subdot in the main scanning direction, the Rth subdot on the other side X2 of the main scanning direction of the target subdot, and the Dth subdot on the upstream side Y2 of the target subdot in the sub-scanning direction. If at least any of the surrounding reference portions is a non-printing portion (S44: YES), the CPU 7 performs the process of S46. In this way, when a target subdot, which is one of the multiple subdots, is a printed portion (S42: YES), if at least one of the subdots arranged as the Uth subdot on the downstream side Y1 in the sub-scanning direction Y, the Dth subdot on the upstream side Y2 in the sub-scanning direction Y, the Lth subdot on one side X1 in the main scanning direction X, and the Rth subdot on the other side X2 in the main scanning direction X is a non-printed portion (S43: YES, S44: YES), the CPU 7 designates the target subdot as a contour subdot and leaves the image data or print data of the contour subdot ON (S46).

[0045] The surrounding reference portions for the target subdot TS2 are the subdots CR1 to CR3, which are indicated by diagonal grid hatching, and the print data for the subdots CR1 to CR3 is all ON (S44: NO). In this case, the CPU 7 stores the target subdot TS2 as a candidate subdot for replacement (S45) and performs the process of S48. Through the processes of S41 to S48, a portion of the print portion R1 of the partial image B1 shown in FIG. 10 is set as a contour subdot, like the portion R3 indicated by the dark hatching in the partial image B2, and the remaining portion R4 is set as a candidate subdot for replacement. In this way, if a target subdot, which is one of the plurality of subdots, is a print portion (S42: YES), and if the Uth subdot arranged on the downstream side Y1 in the sub-scanning direction Y relative to the target subdot, the Dth subdot arranged on the upstream side Y2 in the sub-scanning direction Y relative to the target subdot, the Lth subdot arranged on one side X1 in the main scanning direction X, and the Rth subdot arranged on the other side X2 in the main scanning direction X are all print portions (S43: NO, S44: NO), the CPU 7 designates the target subdot as a candidate subdot to be changed (S45). The CPU 7 changes the print data of at least one or more candidate subdots to be changed from ON to OFF in all sublines in at least one line among all candidate subdots in the image data by the processes of S49 to S53 below.

[0046] If all subdots are acquired as target subdots in the process of S41 (S48: YES), the CPU 7 acquires the change method for one or more change candidate subdots stored in S45 (S49). The change method may be specified by the user, or may be selected by the CPU 7 depending on the type, size, printing speed, print quality, etc. of the input image G. The printing device 1 of this embodiment can select one of four change methods.

[0047] 11, an example will be described in which the four types of modification methods are applied to partial image V. Partial image V is an image in which the number of dots in the main scanning direction X and the number of dots in the sub-scanning direction Y are five and seven, respectively. Of the sub-dots that make up partial image V, the sub-dots indicated by dark shading are set as outline sub-dots, and the sub-dots indicated by light shading are set as modification candidate sub-dots.

[0048] The first modification method modifies the print data for the modification candidate subdots from ON to OFF at a ratio of B / C (B and C are natural numbers) in the main scanning direction X and B / C in the sub-scanning direction Y. B / C may be set to a value greater than 0 and less than 1, preferably 0.5 or less. For example, B / C is 1 / 5. When the first modification method is applied and fractional numbers are generated for the modification candidate subdots in the main scanning direction X and the sub-scanning direction Y, as in partial image V of FIG. 11 , the first modification method may be applied to a range where the first modification method is applicable, as in partial image V1, and other methods may be applied to other ranges. Taking into consideration cases where fractional numbers are generated for the modification candidate subdots in the main scanning direction X and the sub-scanning direction Y when the first modification method is applied, the CPU 7 may set B / C as a target value and set the number of modification candidate subdots to be modified from ON to OFF so as to be closest to the target value.

[0049] The second change method is a method in which, when the print data of a subdot of interest is ON and the subdot adjacent to the subdot of interest on the upstream side Y2 or downstream side Y1 in the sub-scanning direction Y is a change subdot, the print data of the subdot of interest remains ON. In other words, the second change method is a method in which change subdots that change from ON to OFF are not consecutive in the sub-scanning direction Y, as in partial image V2 in Figure 11.

[0050] The third change method leaves the print data of the target subdot ON if the print data of the target subdot is ON and at least one of the subdots adjacent to the target subdot in the main scanning direction X is a change subdot. In other words, the third change method is a method in which change subdots that change from ON to OFF are not consecutive in the main scanning direction X, as in partial image V3 in Figure 11.

[0051] The fourth change method leaves the print data of the target subdot ON if the print data of the target subdot is ON and at least one of the eight subdots surrounding the target subdot is a change subdot. In other words, the fourth change method is a method in which change subdots that are changed from ON to OFF are not consecutive in eight directions, as in partial image V4 in Figure 11. The eight directions in Figure 11 are the upper, upper right, right, lower right, lower, lower left, left, and upper left sides of the target subdot. In the second to fourth change methods, the ratio of change subdots to change candidate subdots in the main scanning direction X and the sub-scanning direction Y may be set appropriately.

[0052] The CPU 7 acquires a change candidate subline, which is a subline formed by one or more change candidate subdots stored in S45, in a predetermined order (S50). In this embodiment, the CPU 7 acquires the change candidate sublines in order from the downstream side Y1 in the sub-scanning direction. For example, the CPU 7 acquires the change candidate subline CL furthest downstream in the sub-scanning direction Y1 in the portion R4. The CPU 7 sets the change candidate subdots of the change candidate subline acquired in S50 according to the change method acquired in S49 (S51). For example, the CPU 7 changes the subdot CS1 included in the change candidate subline CL to a change subdot. The CPU 7 changes the print data of the subdot changed to a change subdot in S51 from ON to OFF (S52). The CPU 7 determines whether all change candidate sublines have been acquired in the process of S50 (S53). If there is a subline that has not been acquired in the process of S50 (NO in S53), the CPU 7 returns to the process of S50. If all the proposed sublines have been acquired in S50 (S53: YES), the CPU 7 ends the modification process and returns to the printing process of FIG. 3. When the fourth modification method is applied to partial image B2 in FIG. 10, the print data for modification subdots CS1 to CS5 is changed from ON to OFF, as in partial image B3, for example. On the other hand, as shown in FIG. 12, when the fourth modification method is applied to partial image C1 to which the first editing method was applied in S12 in S15, the print data is changed, as in partial image C2, for example. As shown in FIG. 13, when editing is performed using the second editing method under the conditions that the resolution is 165 dpi and the absolute value of the difference in the predetermined amount between any two adjacent partial images in the main scanning direction X is 150 μm, editing and modification processes can be performed on ruled lines extending in the main scanning direction X with thicknesses of 1 dot, 2 dots, 3 dots, 4 dots, 6 dots, 8 dots, and 16 dots. This reduces the number of ON dots while still tilting the ruled lines to a degree that is imperceptible to the naked eye. More specifically, the edited areas of the printed image under the conditions shown in FIG. 13 are less noticeable to the naked eye than the printed image edited using the second editing method under the comparative example conditions shown in FIG. 20, where the resolution is 165 dpi and the absolute value of the difference between the predetermined amounts of any two partial images adjacent in the main scanning direction X is 300 μm.When the resolution is 165 dpi, the length of one dot in the sub-scanning direction Y is approximately 154 μm. Figures 13 and 20 show the case where the values ​​of U and D are 3 (corresponding to one dot) and the change process is performed using the third change method, which satisfies the condition that B / C is 1 / 2.

[0053] After S15 or S16, the CPU 7 determines whether the target image is the input image G or a high-resolution image (S17). If the target image is the input image G or a high-resolution image (S17: YES), the CPU 7 does not perform the process of combining the partial images (S19). If the target image is the non-characteristic portion H and the target image has been edited using the sixth editing method (S17: NO), the CPU 7 edits the print data to generate data for printing a composite image G9, which is a combination of the edited image H6 edited in S12, which is the target of the processes from S11 to S16, and the characteristic portion P4, which was not the target of the processes from S11 to S16, as shown in FIG. 14 (S18). The characteristic portion P4 of the composite image G9 completely matches the characteristic portion P4 of the input image G or the high-resolution image because it has not been edited or changed. The portion of the composite image G9 excluding the characteristic portion P4 has been edited and changed, and therefore has portions that do not match the portions of the input image G or the high-resolution image excluding the characteristic portion P4. The same applies when the target image is the target portion H (S17: NO) (S18).

[0054] If the target image is target portions P1 to P3 and has been edited using the first editing method (S17: NO), CPU 7 edits the print data (S18) to produce a composite image G10 that combines target portions P1 to P3, which were the target of the processes S11 to S16 and edited in S12, with non-target portion J, which was not the target of the processes S11 to S16, as shown in FIG. 15. The portions of composite image G10 excluding target portions P1 to P3 have not been edited or modified, and therefore completely match the portions of input image G or the high-resolution image excluding target portions P1 to P3. The portions of composite image G10 excluding target portions P1 to P3 have been edited or modified, and therefore have portions that do not match the portions of input image G or the high-resolution image excluding target portions P1 to P3. In composite image G10, when the dots that make up input image G and the dots that make up the print image printed according to the print data are compared in units of columns, which are dots that are continuously lined up in the sub-scanning direction Y in target portion P1, which is a part of the area from the upstream end DE on the upstream side Y2 in the sub-scanning direction Y to the downstream end UE on the downstream side Y1 in the sub-scanning direction Y, the first, second, and third conditions are satisfied. Similarly, the first, second, and third conditions are also satisfied for target portions P2 and P3.

[0055] After S18 or S19, the CPU 7 determines whether to perform divided printing (S20). Divided printing is a printing method in which multiple elements 61 are divided into N blocks (N is an integer greater than or equal to 2) so that the peak current of the print head 6 required to print one line based on the print data is kept below the maximum current that can be supplied from the power supply 10 to the print head 6, and each of the N blocks is driven sequentially at different timings to print one line of the print data extending in the main scanning direction X. The criteria for determining whether to perform divided printing may be determined as appropriate. For example, the CPU 7 may determine whether to perform divided printing based on the number of on dots per line. If divided printing is to be performed (S20: YES), the CPU 7 edits the print data so that at least some of the lines included in the print data are divided into N blocks in the sub-scanning direction Y (S21). The division method may be determined as appropriate. In this embodiment, the CPU 7 divides the printing cycle of one line into a plurality of sub-printing cycles that are the same length and that start at the same time as the printing cycle. The CPU 7 may set the division method depending on the editing method used in S12.

[0056] When the print data is edited in the editing process of S12 so that the difference in the predetermined amount between any two adjacent columns in the main scanning direction X increases from one side X1 to the other side X2 in the main scanning direction X toward the upstream side Y2 in the sub-scanning direction, as shown in image M1 of Fig. 16, the CPU 7 edits the print data in the divided printing process so that each of the multiple elements 61 in N blocks is driven at different timings in the order from one side X1 to the other side X2 in the main scanning direction X, as shown in image M2 of Fig. 16. The line with identification number 1 in image M1 is divided into two lines, one with identification number 1 and one with identification number 1', in image M2. Similarly, the line with identification number 2 in image M1 is divided into two lines, one with identification number 2 and one with identification number 2', in image M2. In the editing process of S12, when the print data is edited so that the difference in the predetermined amount between any two adjacent columns in the main scanning direction X increases from the other side X2 to one side X1 in the main scanning direction X toward the upstream side Y2 in the sub-scanning direction, as shown in image M3 of FIG. 17 , the CPU 7 then edits the print data in the divided printing process so that each of the multiple elements 61 in N blocks is driven at different timings in the order from the other side X2 to one side X1 in the main scanning direction X, as shown in image M4 of FIG. The line with identification number 1 in image M3 is divided into two lines, one with identification number 1 and one with identification number 1', in image M4. Similarly, the line with identification number 2 in image M3 is divided into two lines, one with identification number 2 and one with identification number 2', in image M4. The CPU 7 sets the start timing of each sub-dot to be evenly spaced.

[0057] CPU7 is S2 1 Based on the print data edited in step S20, divided printing is performed (S23). The CPU 7 performs divided printing by driving a plurality of elements 61 for each of a plurality of sub-print cycles. If divided processing is not performed (S20: NO), the CPU 7 performs print processing based on the print data of S18 or S19 (S22). The CPU 7 sets the heat generation amount of the change candidate sub-dots to be larger than that of the outline sub-dots in accordance with the print data, and in S22 or S23, the CPU 7 performs print processing to form an image on the print target F by heating the plurality of elements 61 (S22, S23). S23 or SAfter step 22, the CPU 7 ends the printing process.

[0058] The modification process of the modified example will be described with reference to FIG. 19. In FIG. 19, the same processes as those in the modification process of the embodiment shown in FIG. 9 are assigned the same reference numerals. As shown in FIG. 19, the modification process of the modified example differs from the modification process of the embodiment shown in FIG. 9 in that the process of S44 is not executed. In the modification process of the modified example, if a target subdot, which is one of the subdots, is a print part (S42: YES), the CPU 7 sets the subdot that is Uth (U is an integer equal to or greater than 0) downstream Y1 from the target subdot in the sub-scanning direction Y as a reference subdot, and if the reference subdot is a print part (S43: NO), sets the reference subdot as a candidate subdot to be modified (S45). The other processes are the same as those in FIG. 9, and therefore will not be described again.

[0059] In the above embodiment, the printing device 1 is an example of the printing device and print data editing device of the present invention. The multiple elements 61, print head 6, transport unit 5, CPU 7, and communication unit 4 are each an example of the multiple elements, print head, transport unit, control unit, and communication unit of the present invention. The process of S1 is an example of the image data acquisition process of the present invention. The process of S12 is an example of the editing process of the present invention. The process of S15 is an example of the change process of the present invention. The process of S23 is an example of the divided printing process of the present invention. The processes of S22 and S23 are examples of the printing process of the present invention.

[0060] The printing device 1 of the above embodiment includes a print head 6, a transport unit 5, and a CPU 7. The printing device 1 has a plurality of elements 61 arranged in a line in the main scanning direction X. The transport unit 5 moves the print target and the print head 6 relative to each other in a sub-scanning direction Y that intersects with the main scanning direction X. The printing device 1 drives the plurality of elements 61 while moving the print head 6 relative to the print target F in the sub-scanning direction Y according to print data including data instructing each of the elements 61 to be ON / OFF, thereby editing print data used by the printing device 1 to form an image on the print target F line by line corresponding to the plurality of elements 61 arranged in the main scanning direction X. The CPU 7 acquires image data corresponding to the plurality of elements 61 arranged in the main scanning direction X (S1). The CPU 7 then performs an editing process to edit the print data corresponding to the image data (S12). Specifically, based on the image data, the CPU 7 performs an editing process to edit print data in which, when the CPU 7 compares the multiple dots that make up the input image G represented by the image data with the multiple dots that make up the print image printed according to the print data in units of columns, which are multiple dots that are lined up continuously in the sub-scanning direction Y in at least a portion of the distance from the upstream end DE on the upstream side Y2 in the sub-scanning direction Y to the downstream end UE on the downstream side Y1, the image included in the column of the print image has the highest degree of match when it is positioned at the same position as the image represented by the column of the input image G or when it is slid a predetermined amount in the sub-scanning direction Y, and the maximum value of the absolute values ​​of the multiple predetermined amounts for the multiple columns is 1 dot or more (S12). The CPU 7 defines a printing unit obtained by dividing a dot defined by multiple elements 61 into M units (M is an integer greater than or equal to 2) in the secondary scanning direction Y as a subdot, defines multiple subdots lined up in the primary scanning direction X as a subline, and defines subdots for which the print data is ON as a printed portion, and subdots for which the print data is OFF or portions outside the printing area as a non-printed portion.The CPU 7 then performs modification processing to change the image data or print data of at least one or more modified subdots, which are at least one subdot, from ON to OFF in at least one subline in at least one line within the printed portion (S15).By performing the editing processing, the printing device 1 can edit print data that suppresses the peak current of the print head 6 required to print one line.By executing the change process in addition to the edit process, the printing device 1 can further reduce the possibility that the peak current supplied to the print head 6 will exceed the maximum current that can be supplied from the power supply 10, while maintaining print quality. By reducing the number of elements 61 that are turned ON in one line, the printing device 1 can increase the possibility of increasing the printing speed compared to conventional methods that do not execute the edit process and change process. Therefore, the printing device 1 can edit print data that can improve both print quality and print speed compared to conventional methods.

[0061] In the editing process, the CPU 7 of the printing device 1 edits the print data that satisfies a second condition that the absolute value of the difference in the predetermined amount between any two adjacent columns in the main scanning direction X is 1 dot or less (S12). Because the absolute value of the difference in the predetermined amount between two adjacent columns in the main scanning direction X is 1 dot or less, the changes made to the input image G in the printed image are less noticeable than when the absolute value of the difference in the predetermined amount is greater than 1 dot, and the changes can be kept to a level that is not noticeable to the naked eye.

[0062] In the editing process, the CPU 7 of the printing device 1 edits print data such that, when compared in columns including all dots between the upstream end DE on the upstream side Y2 in the sub-scanning direction Y and the downstream end UE on the downstream side Y1 as multiple dots lined up consecutively in the sub-scanning direction Y, the images included in the columns of the print image have the highest degree of match when they are positioned at the same position as the images represented by the columns of the input image G or when they are shifted a predetermined amount in the sub-scanning direction Y, and the maximum absolute value of multiple predetermined amounts for the multiple columns is one dot or more (S12). For example, the CPU 7 acquires data representing image H shown in FIG. 8 as image data representing the input image G and edits the print data corresponding to the image data to data corresponding to any of images H1 to H6. The printing device 1 can simplify the editing process compared to when editing only a portion of the sub-scanning direction Y. More specifically, the printing device 1 can omit the process of generating a composite image, as in S18.

[0063] In the change process of S15, if a target subdot, which is one of the multiple subdots, is in the printing portion, the printer 1 sets the subdot that is located Uth (U is any integer greater than or equal to 0) downstream Y1 from the target subdot in the sub-scanning direction Y as a reference subdot, and if the reference subdot is in the non-printing portion (S43: YES), sets the target subdot as a contour subdot and leaves the image data or print data of the contour subdot ON (S46). Thus, the printer 1 can edit print data that is less likely to cause blurring at the printing start point.

[0064] In the change process, if a target subdot, which is one of the multiple subdots, is in the print portion, and at least one of the following is not in the print portion: the Uth subdot (U is any integer equal to or greater than 0) located downstream Y1 in the sub-scanning direction Y with respect to the target subdot; the Dth subdot (D is any integer equal to or greater than 0) located upstream Y2 in the sub-scanning direction Y with respect to the target subdot; the Lth subdot (L is any integer equal to or greater than 0) located on one side X1 in the main scanning direction X; and the Rth subdot (R is any integer equal to or greater than 0) located on the other side X2 in the main scanning direction X (S43: YES, S44: YES), the CPU 7 designates the target subdot as a contour subdot and leaves the image data or print data of the contour subdot ON (S46). The printing device 1 can edit print data that is less likely to cause blurring at the contours of the image formed on the printing object F.

[0065] In the printing device 1 of the modified example, if the reference subdot for the target subdot is in the printing portion in the change process of S15 (S43: NO), the target subdot is designated as a candidate subdot for change (S45), and the image data or print data of at least one candidate subdot for change in all sublines in at least one line among all candidate subdots in the image data is changed from ON to OFF (S51, S52). The printing device 1 can reduce the number of ON subdots in a portion of the printing portion where blurring is less likely to occur than at the start of printing.

[0066] In the change process of S15, if a target subdot that is one of the plurality of subdots is a print portion (S42: YES), and if the U-th subdot (U is any integer equal to or greater than 0) arranged on the downstream side Y1 in the sub-scanning direction Y, the D-th subdot (D is any integer equal to or greater than 0) arranged on the upstream side Y2 in the sub-scanning direction Y, the L-th subdot (L is any integer equal to or greater than 0) arranged on one side X1 in the main scanning direction X, and the R-th subdot (R is any integer equal to or greater than 0) arranged on the other side X2 in the main scanning direction X are all print portions (S43: NO, S44: NO), the CPU 7 sets the target subdot as a change candidate subdot (S45), and changes the print data of at least one or more change candidate subdots from ON to OFF in all sublines in at least one line among all change candidate subdots in the image data (S51, S52). 5 2) The printing device 1 can reduce the number of ON subdots in the printed area where blurring is less likely to occur than in the outline area.

[0067] In the editing process, the CPU 7 edits the print data that satisfies the condition that the absolute value of the difference in the predetermined amount between any two adjacent columns in the main scanning direction X is 150 μm or less (S12). Because the absolute value of the difference in the predetermined amount between two adjacent columns in the main scanning direction X is 150 μm or less, the changes in the printed image from the input image G are less noticeable than when the absolute value of the difference in the predetermined amount is greater than 150 μm, and the changes can be kept to a level that is not noticeable to the naked eye.

[0068] CPU 7 further executes a divided printing process (S21, S23) in which the plurality of elements 61 are divided into N blocks (N is an integer greater than or equal to 2) so as to keep the peak current of print head 6 required to print one line based on the print data below the maximum current that can be supplied from power supply 10 to print head 6, and the plurality of elements 61 are driven in block units, with each of the N blocks driven in sequence at different timings. Even if the peak current supplied to print head 6 when printing one line based on edited print data exceeds the maximum current that can be supplied from power supply 10, printing device 1 can maintain print quality while preventing the peak current from exceeding the maximum current that can be supplied from power supply 10.

[0069] The printing device 1 includes a print head 6 having a plurality of heating elements arranged in the main scanning direction X as a plurality of elements 61, and a transport unit 5. The CPU 7 executes a printing process to form an image on the printing object F by heating the plurality of elements 61 in accordance with the printing data (S22, S23). The printing device 1 can perform thermal printing while maintaining print quality and ensuring that the peak of the current supplied to the print head 6 does not exceed the maximum current that can be supplied from the power source 10. The printing object F is a thermal recording medium. The printing device 1 ,mark An image can be formed on the thermal recording medium while maintaining print quality and ensuring that the peak current supplied to the print head 6 does not exceed the maximum current that can be supplied from the power supply 10.

[0070] The CPU 7 executes a printing process that forms an image on the print target F by setting the heat generation amount of the candidate change sub-dots to be greater than that of the outline sub-dots and heating the multiple elements 61 in accordance with the print data (S22, S23). The printing device 1 can perform thermal printing while maintaining print quality so that the peak current does not exceed the maximum current that can be supplied from the power source 10. By switching the candidate change sub-dots from ON to OFF, the printing device 1 can reduce the number of sub-dots in one line while more reliably heating the candidate change sub-dots, thereby improving print quality compared to when the heat generation amount of the candidate change sub-dots is the same as that of the outline sub-dots.

[0071] The print data editing device, print data editing method, and print data editing program of the present invention are not limited to the above-described embodiments and may be modified in various ways without departing from the spirit and scope of the present invention. For example, the following modifications may be made as appropriate. The present invention can be implemented in various forms, such as a non-transitory computer-readable medium storing a print data editing program. The configuration of the printing device 1 may be modified as appropriate. The printing device 1 may be a printing device having a line thermal head that thermally transfers an ink ribbon as the print head 6. The printing device 1 may be an inkjet printer having a line inkjet head as the print head 6, with a plurality of piezoelectric elements as the plurality of elements 61. The printing device 1 may be an electrophotographic printer having a line LED head as the print head 6, with a plurality of LEDs (light-emitting diodes) as the plurality of elements 61. The print data editing device may be a dedicated or general-purpose device provided separately from the printing device 1 and performing processes S1 to S19. The printing device 1 may change the configuration of the transport unit 5 depending on the type of print head 6. The transport unit 5 may change the relative position between the print head 6 and the printing target by moving the print head 6. The communication unit 4 may be configured to be able to communicate with the external device W wirelessly or via a wire.

[0072] figure 3 The program containing the instructions for executing the above processes may be stored in the storage device of the printing device 1 before the CPU 7 executes the corresponding program. Therefore, the program acquisition method, acquisition path, and device storing the program may each be changed as appropriate. The program executed by each printing device 1 may be received from another device via a cable or wireless communication and stored in a storage device such as a memory unit. The other device may include, for example, a PC and a server connected via a network.

[0073] The steps of the printing process are not limited to being executed by the CPU 7, and may be executed in part or in whole by other electronic devices (e.g., ASIC). The steps of the printing process may be distributed among multiple electronic devices (e.g., multiple CPUs). The order of the steps of the printing process may be changed, and steps may be omitted or added as necessary. The following modifications may be made to the printing process as appropriate.

[0074] The types and number of editing methods executable by the CPU 7 may be changed as appropriate. For example, the CPU 7 may be capable of executing only one of the first through sixth editing methods. The CPU 7 may perform editing processing on the high-resolution image in S3 or the input image G in S4 without accepting designation of at least one of the characteristic portion, target portion, and non-target portion. When multiple target portions P1 to P3 are set, the CPU 7 may apply the same editing method to each target portion, or may apply different editing methods to each target portion. The CPU 7 may perform editing processing without determining whether to perform editing processing in S11. When a characteristic portion or non-target portion is designated, the CPU 7 may perform editing processing by setting a predetermined amount in the main scanning direction X within a range including the designated portion to 0. The second and third editing conditions may be omitted as appropriate.

[0075] The CPU 7 may execute the modification process without determining whether to execute the modification process in S14. The types and number of modification methods executable by the CPU 7 may be changed as appropriate. For example, the CPU 7 may be capable of executing only one of the first through fourth modification methods. The CPU 7 may also execute the modification process using a method other than the first through fourth modification methods. As shown in FIG. 18, the CPU 7 may edit the print data of print image J2 based on the image data of input image J1, and then execute the modification process to generate print image J4. Alternatively, the CPU 7 may execute the modification process to generate print image J3 based on the image data of input image J1, and then execute the editing process to generate print image J4. In the modification process, the CPU 7 may change the image data or print data of at least one or more modification subdots, which are at least one subdot, from ON to OFF in at least one subline in at least one line within the print area. The CPU 7 does not need to set the heat generation value of the modification candidate subdots higher than that of the outline subdots in S22 or S23. The CPU 7 may omit the processes of S40 to S48 and execute the modification process by treating all subdots that make up the print area as modification candidate subdots. The CPU 7 may change the set number of change candidate sub-dots according to the number of change candidate sub-dots included in the change candidate sub-line acquired in S50.

[0076] The processes of S21 and S23 may be omitted as appropriate. The CPU 7 may execute the processes of S21 and S23 without determining whether to divide the line in S20. When performing divided printing, the CPU 7 may determine the drive order of the elements 61 of multiple blocks regardless of the editing method in S12. The processes of S2 to S4 may be omitted or changed as appropriate. The above modified examples may be combined as appropriate within a range that does not cause inconsistencies. [Explanation of symbols]

[0077] 1: Printing device, 4: Communication unit, 5: Conveying unit, 6: Print head, 7: CPU, 8: RAM, 9: Storage unit

Claims

1. A print data editing device for editing print data used in a printing device, comprising: The printing device a print head having a plurality of elements arranged in a line in the main scanning direction; a conveying unit that moves the print object and the print head relatively in a sub-scanning direction that intersects with the main scanning direction; a printing device that drives the plurality of elements while moving the print head relative to the printing target in the sub-scanning direction in accordance with print data that includes data instructing ON / OFF of each of the plurality of elements, and forms an image on the printing target for each line corresponding to the plurality of elements arranged in the main scanning direction, The print data editing device includes a control unit, The control unit an image data acquisition process for acquiring image data corresponding to the plurality of elements arranged in the main scanning direction; an editing process that edits the print data corresponding to the image data, the editing process being such that, when a plurality of dots constituting an input image represented by the image data and a plurality of dots constituting a print image printed in accordance with the print data are compared on a column basis, each column being a plurality of dots that are successively lined up in the sub-scanning direction in at least a portion between an upstream end on the upstream side in the sub-scanning direction and a downstream end on the downstream side in the sub-scanning direction, the image included in the column of the print image has a maximum degree of match when the image represented by the column of the input image is positioned at the same position as the image represented by the column of the input image or is shifted by a predetermined amount in the sub-scanning direction, and the maximum value of the plurality of absolute values ​​of the predetermined amounts for the plurality of columns is one dot or more; a printing unit obtained by dividing the dot defined by the plurality of elements into M units (M is an integer of 2 or more) in the sub-scanning direction is defined as a sub-dot, a plurality of the sub-dots arranged in the main scanning direction is defined as a sub-line, the sub-dots for which the print data is ON are defined as a printing portion, and the sub-dots for which the print data is OFF or a portion outside the printing area are defined as a non-printing portion, a change process of changing the image data or the print data of at least one or more change sub-dots, which are the sub-dots, from ON to OFF in at least one of the sub-lines in at least one of the lines in the printing portion; is executable, the control unit edits the print data in the editing process so as to satisfy a condition that the absolute value of the difference in the predetermined amount between any two of the columns adjacent to each other in the main scanning direction is 1 dot or less; the degree of coincidence indicates the degree of coincidence between ON / OFF of the subdots, The printing data editing device according to the present invention, wherein the conditions further include a condition that the absolute value of one or more of the differences is a value less than one dot represented by the subdots.

2. 2. The print data editing device according to claim 1, wherein the control unit, in the editing process, edits the print data such that, when compared in column units that include all the dots between the upstream end on the upstream side in the sub-scanning direction and the downstream end on the downstream side as the multiple dots lined up continuously in the sub-scanning direction, the image included in the column of the print image has the greatest degree of match when it is at the same position as the image represented by the column of the input image or when it is slid by the predetermined amount in the sub-scanning direction, and the maximum value of the absolute values ​​of the multiple predetermined amounts for the multiple columns is 1 dot or more.

3. The control unit, in the change process, when a target subdot, which is one of the plurality of subdots, is in the printing part, sets the subdot located Uth (U is an integer equal to or greater than one) downstream of the target subdot in the sub-scanning direction as a reference subdot, and when the reference subdot is in the non-printing part, sets the target subdot as a contour subdot and leaves the image data or printing data of the contour subdot ON.

4. 3. The print data editing device of claim 1, wherein, in the change process, when a target subdot among the plurality of subdots is the printing portion, if at least one of the subdots located Uth (U is any integer equal to or greater than one) downstream of the target subdot in the sub-scanning direction, the subdot Dth (D is any integer equal to or greater than one) upstream of the target subdot in the sub-scanning direction, the subdot Lth (L is any integer equal to or greater than one) on one side of the main scanning direction, and the subdot Rth (R is any integer equal to or greater than one) on the other side of the main scanning direction is the non-printing portion, the control unit sets the target subdot to a contour subdot and leaves the image data or print data of the contour subdot ON.

5. The printing data editing device described in claim 3, characterized in that, in the change process, when the reference subdot of the target subdot is the printing part, the control unit sets the target subdot as a change candidate subdot, and changes the image data or print data of at least one or more of the change candidate subdots from ON to OFF in all sublines in at least one of the lines among all the change candidate subdots in the image data.

6. 5. The print data editing device according to claim 4, wherein, in the modification process, when the target subdot is the printing portion, if the subdot U-th (U is any integer equal to or greater than one) downstream of the target subdot in the sub-scanning direction, the subdot D-th (D is any integer equal to or greater than one) upstream of the target subdot in the sub-scanning direction, the subdot L-th (L is any integer equal to or greater than one) on one side of the main scanning direction, and the subdot R-th (R is any integer equal to or greater than one) on the other side of the main scanning direction are each the printing portion, the control unit sets the target subdot as a modification candidate subdot, and changes the print data of at least one or more of the modification candidate subdots from ON to OFF in all of the sublines in at least one of the lines among all of the modification candidate subdots in the image data.

7. the print data editing device is the printing device including the print head and the transport unit, The control unit 7. The print data editing device of claim 1, further comprising: dividing the plurality of elements into N blocks (N is an integer of 2 or more) so as to keep the peak current of the print head required when printing one line based on the print data below the maximum current that can be supplied from a power supply to the print head; and driving each of the plurality of elements in block units, with each of the N blocks driven in sequence at different timings, thereby executing a divided printing process that prints one line extending in the main scanning direction of the print data.

8. the print data editing device is the printing device including the print head having a plurality of heat generating elements aligned in the main scanning direction as the plurality of elements, and the transport unit; 8. The print data editing device according to claim 1, wherein the control unit executes a print process to form the image on the printing object by heating the plurality of heating elements in accordance with the print data.

9. 9. The print data editing device according to claim 8, wherein the printing object is a thermal recording medium.

10. the print data editing device is the printing device including the print head having a plurality of heat generating elements aligned in the main scanning direction as the plurality of elements, and the transport unit; the printing target is a thermal recording medium, the control unit executes a printing process to form the image on the printing target by heating the plurality of heating elements in accordance with the print data; The control unit executes a printing process to form the image on the printing object by setting the heat generation amount of the candidate sub-dots to be greater than that of the contour sub-dots in accordance with the printing data and heating the multiple heating elements, as described in claim 5 or 6.

11. A print data editing method executed by a control unit of a print data editing device that edits print data used in a printing device, comprising: The printing device a print head having a plurality of elements arranged in a line in the main scanning direction; a conveying unit that moves the print object and the print head relatively in a sub-scanning direction that intersects with the main scanning direction; a printing device that drives the plurality of elements while moving the print head relative to the printing target in the sub-scanning direction in accordance with print data that includes data instructing ON / OFF of each of the plurality of elements, and forms an image on the printing target for each line corresponding to the plurality of elements arranged in the main scanning direction, The print data editing method includes: an image data acquisition process for acquiring image data corresponding to the plurality of elements arranged in the main scanning direction; an editing process that edits the print data corresponding to the image data, the editing process being such that, when a plurality of dots constituting an input image represented by the image data and a plurality of dots constituting a print image printed in accordance with the print data are compared on a column basis, each column being a plurality of dots that are successively lined up in the sub-scanning direction in at least a portion between an upstream end on the upstream side in the sub-scanning direction and a downstream end on the downstream side in the sub-scanning direction, the image included in the column of the print image has a maximum degree of match when the image represented by the column of the input image is positioned at the same position as the image represented by the column of the input image or is shifted by a predetermined amount in the sub-scanning direction, and the maximum value of the plurality of absolute values ​​of the predetermined amounts for the plurality of columns is one dot or more; a printing unit obtained by dividing the dot defined by the plurality of elements into M units (M is an integer of 2 or more) in the sub-scanning direction is defined as a sub-dot, a plurality of the sub-dots arranged in the main scanning direction is defined as a sub-line, the sub-dots for which the print data is ON are defined as a printing portion, and the sub-dots for which the print data is OFF or a portion outside the printing area are defined as a non-printing portion, a change process of changing the image data or the print data of at least one or more change sub-dots, which are the sub-dots, from ON to OFF in at least one of the sub-lines in at least one of the lines in the printing portion; Equipped with the editing process is a process of editing the print data that satisfies a condition that the absolute value of the difference in the predetermined amount between any two of the columns adjacent to each other in the main scanning direction is 1 dot or less, the degree of coincidence indicates the degree of coincidence between ON / OFF of the subdots, The print data editing method, wherein the conditions further include a condition that the absolute value of one or more of the differences is a value less than one dot represented by the subdots.

12. A print data editing program executed by a control unit of a print data editing device that edits print data used in a printing device, comprising: The printing device a print head having a plurality of elements arranged in a line in the main scanning direction; a conveying unit that moves a print object and the print head relatively in a sub-scanning direction that intersects with the main scanning direction, and drives the plurality of elements while moving the print head relatively to the print object in the sub-scanning direction in accordance with print data that includes data instructing ON / OFF of each of the plurality of elements, thereby forming an image on the print object for each line corresponding to the plurality of elements lined up in the main scanning direction; The print data editing program an image data acquisition process for acquiring image data corresponding to the plurality of elements arranged in the main scanning direction; an editing process that edits the print data corresponding to the image data, the editing process being such that, when a plurality of dots constituting an input image represented by the image data and a plurality of dots constituting a print image printed in accordance with the print data are compared on a column basis, each column being a plurality of dots that are successively lined up in the sub-scanning direction in at least a portion between an upstream end on the upstream side in the sub-scanning direction and a downstream end on the downstream side in the sub-scanning direction, the image included in the column of the print image has a maximum degree of match when the image represented by the column of the input image is positioned at the same position as the image represented by the column of the input image or is shifted by a predetermined amount in the sub-scanning direction, and the maximum value of the plurality of absolute values ​​of the predetermined amounts for the plurality of columns is one dot or more; a printing unit obtained by dividing the dot defined by the plurality of elements into M units (M is an integer of 2 or more) in the sub-scanning direction is defined as a sub-dot, a plurality of the sub-dots arranged in the main scanning direction is defined as a sub-line, the sub-dots for which the print data is ON are defined as a printing portion, and the sub-dots for which the print data is OFF or a portion outside the printing area are defined as a non-printing portion, a change process of changing the image data or the print data of at least one or more change sub-dots, which are the sub-dots, from ON to OFF in at least one of the sub-lines in at least one of the lines in the printing portion; and an instruction to cause the control unit to execute the the editing process is a process of editing the print data that satisfies a condition that the absolute value of the difference in the predetermined amount between any two of the columns adjacent to each other in the main scanning direction is 1 dot or less, the degree of coincidence indicates the degree of coincidence between ON / OFF of the subdots, The print data editing program is characterized in that the conditions further include a condition that the absolute value of one or more of the differences is a value less than one dot represented by the subdots.

Images