JP5880386B2 - Image processing apparatus, image forming system, and program - Google Patents

Description

  The present invention relates to an image processing apparatus, an image forming system, and a program.

  A code image (so-called bar code) that represents information such as numerical values by a plurality of lines arranged in a striped pattern is known. When such a code image is formed on a recording medium such as paper, if a line cannot be formed with an intended width and interval, when reading information from the code image later, reading may fail or false detection may occur. There is a risk. However, when such a code image is formed using an ink jet image forming apparatus, the thickness of the line may be increased depending on the direction of the line due to secondary ink droplets or ink bleeding generated during ink ejection. It may not be well controlled. In view of this, an image forming apparatus that controls the arrangement direction of the code images and an image forming apparatus that narrows the line thickness depending on the arrangement direction have been proposed (see Patent Documents 1 and 2).

JP-A-6-44393 JP 2005-22383 A

  In the present invention, when a code image is formed by an ink jet method, even if a phenomenon (inertance) in which the start of the next discharge is delayed after the ink is discharged, a code image that can be read accurately is formed. An object of the present invention is to provide an image processing apparatus, an image forming system, and a program that can be used.

  According to the first aspect of the present invention, there is provided image acquisition means for acquiring a code image including a plurality of lines and indicating information by the widths of the plurality of lines, and ink generated when the image forming apparatus forms an image. A correction amount determining means for determining a correction amount for the width of each of the plurality of lines according to a delay of the next discharge start after the discharge, and the width of each of the plurality of lines corrected according to the correction amount An image processing apparatus comprising: a forming unit configured to form a code image on the image forming apparatus;

  A second aspect of the present invention is the image processing apparatus according to the first aspect, further comprising a measurement result acquisition unit that acquires a measurement result of a print position shift caused by the delay, and the correction amount determination unit. Determines the correction amount for the width of each of the plurality of lines according to the measurement result.

  A third aspect of the present invention is the image processing apparatus according to the first or second aspect, wherein the code image includes a plurality of lines having different widths, and the correction amount determining means is a line to be corrected. The correction amount is changed in accordance with the width of.

  A fourth aspect of the present invention is the image processing apparatus according to any one of the first to third aspects, wherein the correction amount determining unit uses the information related to printing characteristics of the image forming apparatus to The correction amount for the width of each of the plurality of lines is determined.

  According to a fifth aspect of the present invention, in the image processing apparatus according to the fourth aspect, the information relating to the printing characteristics of the image forming apparatus includes information on the number of ink ejection heads provided in the image forming apparatus. Features.

  The invention described in claim 6 includes: an image forming apparatus that forms an image by ejecting ink; and an image processing apparatus that causes the image forming apparatus to form an image to be formed. As the target image, an image acquisition means for acquiring an image including a plurality of lines and including a code image indicating information by the width of the plurality of lines, and ejecting ink generated when the image forming apparatus forms an image Correction amount determining means for determining a correction amount for the width of each of the plurality of lines according to the delay of the next discharge start after the correction, and the code for correcting the width of each of the plurality of lines according to the correction amount And an image forming apparatus that forms the image to be formed on the image forming apparatus.

  According to a seventh aspect of the present invention, there is provided image acquisition means for acquiring a code image that includes a plurality of lines and indicates information by the widths of the plurality of lines, and discharges ink that occurs when the image forming apparatus forms an image. A correction amount determining means for determining a correction amount for the width of each of the plurality of lines according to the delay of the next discharge start after the correction, and the width of each of the plurality of lines corrected according to the correction amount A program for causing a computer to function as forming means for forming a code image in the image forming apparatus.

  According to the first, sixth, and seventh aspects of the present invention, a code image that can be read accurately can be formed even when inertance occurs.

  According to the second aspect of the present invention, the code image can be corrected according to the degree of inertance actually generated in each image forming apparatus.

  According to the third aspect of the present invention, it is possible to perform correction in consideration of whether or not inertance is generated according to the width of each line to be corrected.

  According to the fourth and fifth aspects of the present invention, the code image can be corrected according to the degree of inertance assumed from the printing characteristics of the image forming apparatus.

1 is a configuration diagram illustrating a schematic configuration of an image forming system according to an embodiment of the present invention. It is a figure which shows an example of a barcode image. It is a figure which shows the example at the time of printing a barcode image without correction | amendment. It is a figure which shows the example at the time of correcting and printing a barcode image. FIG. 10 is a diagram illustrating an example when a barcode image is printed without correction by a dual head image forming apparatus. FIG. 5 is a diagram illustrating an example when a barcode image is corrected and printed by a dual head image forming apparatus. It is a functional block diagram which shows the function which the image processing apparatus which concerns on embodiment of this invention implement | achieves. It is a flowchart which shows an example of the flow of the process which the image processing apparatus which concerns on embodiment of this invention performs. It is a figure which shows an example of the correction amount determination table. It is a flowchart which shows another example of the flow of the process which the image processing apparatus which concerns on embodiment of this invention performs. It is a figure which shows another example of the correction amount determination table.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a configuration diagram illustrating a schematic configuration of an image forming system 1 according to an embodiment of the present invention. The image forming system 1 includes an image forming apparatus 3 that forms an image on a recording medium P such as paper, and an image processing apparatus 2 that outputs image data to be formed by the image forming apparatus 3. Has been. As shown in FIG. 1, the image processing apparatus 2 includes a control unit 11, a storage unit 12, and an output unit 13.

  The control unit 11 is a CPU or the like, and performs various types of information processing according to programs stored in the storage unit 12. The storage unit 12 includes a memory element such as a RAM, and stores a program executed by the control unit 11 and data to be processed by the program. In particular, in the present embodiment, the storage unit 12 stores image data of a formation target image that is to be formed by the image forming apparatus 3.

  The output unit 13 is an interface for the image forming apparatus 3, and transmits data of a formation target image to the image forming apparatus 3 in accordance with an instruction from the control unit 11.

  The image forming apparatus 3 forms an image on a recording medium P (here, it is assumed to be paper) by an ink jet method that ejects ink droplets from an ink ejection head. In the present embodiment, the image forming apparatus 3 forms an image to be formed including the barcode image B on the recording medium P.

  The barcode image B is a one-dimensional code image composed of a plurality of straight lines (bars) arranged in parallel to each other and representing information such as numerical values by the widths of the plurality of bars. In order to read the barcode image B and accurately reconstruct the original information, the width w of each bar and the distance (edge distance) dx from both edges of each bar to the corresponding edge of the adjacent bar It is necessary to accurately reproduce dy on the recording medium P. For example, FIG. 2 schematically shows three bars B1, B2, and B3 included in the barcode image B. In this figure, the width w1 of the bar B1 and the width w3 of the bar B3 are 4 dots in the printing unit (dot) of the image forming apparatus 3, and the width w2 of the bar B2 is 8 dots. In order to read the barcode image B with high accuracy, the widths w1, w2 and w3 of the three bars B1, B2 and B3, the edge distances dx1 and dy1 between the bars B1 and B2, and the bar B2 The distance between the edges dx2 and dy2 between the bar B3 and the bar B3 needs to be printed on the recording medium P with a value close to the ideal value.

  On the other hand, the inkjet image forming apparatus 3 targets the printing position and printing range of dots constituting an image due to ink bleeding, secondary ink droplets (satellite), and a phenomenon called inertance. It may deviate from the position to do. When the barcode image B is printed using such an image forming apparatus 3, the bar width w and the edge distances dx and dy are deviated from the original ideal values, and the barcode image B is read later. There is a risk of reading errors and false detections. Therefore, in the present embodiment, the width w of each bar is corrected in advance assuming the occurrence of such a shift. As a result, the barcode image B is formed on the recording medium P with the width w and the edge distances dx and dy that are close to the ideal value. In particular, when the image forming apparatus 3 is a type of printer that performs printing on a continuous form at a high speed, it is necessary to determine the correction amount in consideration of the influence of inertance. Here, inertance is a phenomenon in which the start of the next ejection is delayed when the ink ejection head attempts to perform the next ejection immediately after ejecting ink in the inkjet image forming apparatus 3. .

  3A and 3B show an example when the barcode image B shown in FIG. 2 is actually printed. FIG. 3A shows an example of printing the barcode image B shown in FIG. 2 without correction, and FIG. 3B shows an example of printing after correcting the width w of each of the bars B1, B2, and B3. Show. In FIGS. 3A and 3B, a straight line area hatched with diagonal lines indicates a line directly printed by the ink ejection head of the image forming apparatus 3, and a straight line area with thin hatching indicates ink bleeding. A line generated around a line printed directly by the above (line generated by line thickening) is shown. Here, it is assumed that bleeding of one dot occurs above and below the printed line. Here, it is assumed that the arrangement direction (vertical direction in the figure) of the bars constituting the barcode image B coincides with the feeding direction of the recording medium P, and one dot is added after the second line of each bar by inertance. It is assumed that the corresponding printing position shift occurs. For example, since the ideal value of the width w1 of the bar B1 is 4 dots, when printing the bar B1 without correction, the image forming apparatus 3 continuously forms four lines L1 to L4. However, due to inertance, the second and subsequent lines L2 to L4 are formed shifted by one dot below the original printing position, and a gap of one dot is generated between the lines L1 and L2. However, this gap is filled by ink bleeding, and one bar is not separated into two.

  When printing is performed without correction as shown in FIG. 3A, the width w of each of the bars B1 to B3 becomes 3 dots larger than the ideal value due to the occurrence of bleeding or inertance. Therefore, the image processing apparatus 2 according to the present embodiment outputs the image data of the barcode image B to the image forming apparatus 3 after performing correction by reducing the width w of each bar by 2 dots in advance. As a result, as shown in FIG. 3B, the deviation of the width w of each bar from the ideal value falls within one dot.

  In the case where the image forming apparatus 3 is a type that performs printing using a plurality of ink ejection heads, the manner in which inertance occurs is also different. For example, as shown in FIG. 3A and FIG. 3B, when the delay due to inertance is within one dot, if the dual head method in which two ink ejection heads perform printing alternately, the printing position shift due to the influence of inertance. Does not occur. This is because each head prints only every other line. However, when a delay of two dots or more occurs due to inertance, the print position shift due to the influence of inertance also occurs in the dual head image forming apparatus 3. The correction in such a case will be described below.

  4A and 4B show an example of printing a barcode image B when the image forming apparatus 3 includes two ink ejection heads, ie, a first head and a second head. FIG. 4A shows a case where no correction is performed. FIG. 4B shows a case with correction. In the examples of these drawings, the first head and the second head are alternately printing one line at a time. In FIG. 4A and FIG. 4B, the hatched hatched straight line area indicates a line printed by the first head, and the vertical hatched line area indicates a line printed by the second head. Show. Similarly to the case of FIGS. 3A and 3B, it is assumed that a blur of one dot is generated around the printing position of the dots by the ink ejection head, and the lines generated by this blur are the same as FIGS. 3A and 3B. Similarly, it is represented by thin hatching. On the other hand, unlike FIGS. 3A and 3B, after each head performs printing for one line by inertance, a delay of two dots occurs until the next printing is performed. For this reason, after each head prints the first line, the position of the next line printed by the same ink discharge head should be originally two dots below the first line. The position will be 3 dots below the eye. As a specific example, in FIG. 4A, among the lines L1 to L4 constituting the bar B1, the lines L1 and L3 are printed by the first head, and the lines L2 and L4 are printed by the second head, respectively. Of these lines, the line L3 should be printed directly below the line L2, but it is printed at a position one dot lower than that by the inertance, and there is a gap of one dot between the line L2 and the line L3. Has occurred. In FIG. 4A, the width w of each bar is 3 dots larger than the ideal value due to the gap of 1 dot generated by such inertance and the lines at both ends generated by line thickening.

  On the other hand, in FIG. 4B, since the printing is performed after the correction to reduce the width w of each bar, the width w of each printed bar matches the ideal value. However, in the example of FIG. 4B, unlike the case of FIG. 3B, the correction amount is changed for each bar. Specifically, for the bars B1 and B3 having an original width w of 4 dots, the width w is corrected by 2 dots. As a result, there are two lines to be formed, and the first head and the second head each print one line at a time to form a bar. Since each head prints only one line, inertance does not occur. On the other hand, unlike the other bars, the bar B2 is corrected to reduce the width w by 3 dots. As a result, the first head has 3 lines, the second head has 2 lines, and a total of 5 lines are printed, including the lines generated at both ends of the bar due to gaps due to inertance and ink bleeding. A bar having a width w corresponding to a dot is formed. As described above, the optimum correction amount may differ for each bar depending on the printing conditions and the degree of inertance generated. In such a case, each bar is printed with a width close to the ideal value by changing the correction amount for the width of the bar according to the width of the bar to be corrected. More specifically, when the bar width is smaller than a predetermined value, depending on the printing conditions, it is not necessary for each head to print a plurality of lines, and it is not necessary to consider the influence of inertance. On the contrary, if the width of the bar is larger than a predetermined value, each head prints a plurality of lines. Therefore, it is necessary to perform correction with a correction value corresponding to the influence of inertance.

  Hereinafter, functions of the image processing apparatus 1 that realize the control as described above will be described. As shown in FIG. 5, the image processing apparatus 1 is functionally configured to include an image acquisition unit 21, a correction amount determination unit 22, and a formation control unit 23. These functions are realized when the control unit 11 executes a program stored in the storage unit 12. This program may be provided to the image processing apparatus 1 via a communication network such as the Internet, or may be stored in a computer-readable information storage medium such as an optical disk and provided to the image processing apparatus 1.

  The image acquisition unit 21 acquires an image (formation target image) to be formed by the image forming apparatus 3. It is assumed that the image to be formed includes a barcode image B.

  The correction amount determination unit 22 determines a correction amount for the width w of each bar included in the barcode image B in the formation target image acquired by the image acquisition unit 21. For example, the correction amount determination unit 22 estimates the deviation of the printing position due to the assumed inertia using the information related to the printing characteristics of the image forming apparatus 3, and determines the correction amount accordingly. Further, the correction amount determination unit 22 may determine the correction amount according to the degree of inertance measured through experiments or the like in the past. Alternatively, the correction amount determination unit 22 measures the degree of inertance actually generated in the image forming apparatus 3 used for forming the barcode image B, and according to the measurement result, the correction amount for the width w of each bar. May be determined. The measurement result is obtained by causing the image forming apparatus 3 to print a measurement image (test pattern) that actually includes a bar having a predetermined width, and reading the image of the print result with a scanner or the like. Is obtained by comparing to the ideal value. By using such a method, a correction amount corresponding to the degree of inertance (inertance level) generated in the image forming apparatus 3 that is actually used is determined. A specific example of how the correction amount determination unit 22 determines the correction amount will be described in detail later.

  The formation control unit 23 outputs a formation target image obtained by correcting the width w of each bar with the correction amount determined by the correction amount determination unit 22 to the image forming apparatus 3 via the output unit 13. An image to be formed is formed on the forming apparatus 3. As a result, a barcode image B is printed in which the width w of each bar and the distance between edges dx and dy are close to ideal values.

  Hereinafter, a specific example of the flow of processing executed by the control unit 11 when printing the formation target image including the barcode image B in the present embodiment will be described with reference to the flowchart of FIG. In the example of this figure, the actual inertance measurement is not performed, and the width w of each bar is corrected using information relating to the known printing characteristics of the image forming apparatus 3.

  First, the control unit 11 acquires information related to the printing characteristics of the image forming apparatus 3 (S1). As a specific example, the control unit 11 acquires information related to the printing speed, the appropriate amount of ink, and the number of heads of the image forming apparatus 3. For example, when the image forming apparatus 3 performs printing on a continuous form, the printing speed is represented by the length of the recording medium P that can be printed per minute. In the present embodiment, the printing speed is assumed to be 200 m / min, 100 m / min, or 50 m / min depending on the type of the image forming apparatus 3. The ink droplet amount is the size of the ink droplet ejected by the ink ejection head. In the present embodiment, it is assumed that the ink droplet amount can be switched in three stages of many, medium, and small according to user settings or the like. The number of heads is the number of ink ejection heads provided in the image forming apparatus 3. Here, it is assumed that the image forming apparatus 3 is either a single head having only one ink ejection head or a dual head having two ink ejection heads. The control unit 11 may acquire the information by an inquiry to the image forming apparatus 3 or may acquire the information based on information input by the user.

  Next, the control unit 11 acquires a formation target image (S2). Then, the arrangement direction of the barcode image B included in the formation target image acquired in S2 is specified as vertical arrangement or horizontal arrangement (S3). Specifically, the control unit 11 determines whether or not the stretching direction of the barcode image B matches the feeding direction of the recording medium P. When the barcode image B is vertically arranged, the stretching direction of the barcode image B (the arrangement direction of each bar in the barcode image B) matches the feeding direction of the recording medium P. An inertance effect occurs. Therefore, it is necessary to correct the width w of each bar using a correction amount considering inertance. On the other hand, when the barcode image B is arranged horizontally, the stretching direction of the barcode image B is orthogonal to the feeding direction of the recording medium P, so the width w of each bar does not change due to the influence of inertance. Therefore, it is only necessary to perform correction with a correction amount that takes into account only ink bleeding or the like.

  Subsequently, the control unit 11 determines a correction amount of the width w for each of the plurality of bars included in the barcode image B, and corrects the width w of the bar with the determined correction amount. Specifically, the control unit 11 determines the correction amount by referring to the correction amount determination table using the information obtained in S1 and S3 and the information on the width w of the bar to be corrected (S4).

  FIG. 7 shows an example of the correction amount determination table. In the example of this figure, information on the printing speed, ink droplet amount, and number of heads acquired in S1, information on the arrangement direction of the barcode image B acquired in S3, and information on the width w of the bar to be corrected A correction amount is associated with the combination of. In the example of FIG. 7, the printing speed of 200 m / min is realized only with the dual head (number of heads 2), and there is no single head column. In the figure, the column corresponding to the horizontal arrangement is a correction amount that does not consider inertance, and the column corresponding to the vertical arrangement is a correction amount considering the inertance. In this case, the correction amount in consideration of the inertance is determined on the assumption of an inertance level that is normally generated in the corresponding printing characteristics. For example, when the printing characteristics are a printing speed of 200 m / min, a large amount of ink droplets, and a dual head, the correction amount is determined on the assumption that a delay due to inertance generally occurs for two dots. In the figure, a correction amount of 0 indicates that no correction is required. In the case of a printing speed of 100 m / min, a large amount of ink droplets, and a single head, the correction amount column cannot be corrected in a vertical arrangement in which inertance occurs. This indicates that printing with a width w close to an ideal value is impossible even if the correction of the bar width w is performed by the correction amount determination unit 22 under the printing conditions. When such a condition is met, the image processing apparatus 2 may stop printing by outputting a warning message, for example.

  Further, the control unit 11 corrects the width w of the bar to be corrected with the correction amount determined in S4 (S5). Thereafter, it is determined whether or not necessary correction has been performed for all the bars (S6). If an unprocessed bar remains, the process returns to S4 to determine the correction amount and correct the unprocessed bar. When necessary correction is performed for all the bars, the corrected formation target image is output to the image forming apparatus 3 to form an image (S7).

  Next, a specific example of the flow of processing when measuring the level of inertance actually generated and determining the correction amount using the measurement result will be described with reference to the flowchart of FIG.

  First, the control unit 11 outputs a test pattern prepared in advance for measuring the inertance level and causes the image forming apparatus 3 to print it (S11). And the measurement result obtained by measuring the printed test pattern is acquired (S12).

  This test pattern is, for example, an image in which bars having a predetermined width are arranged in the vertical direction (the direction that coincides with the feeding direction of the recording medium P) and the horizontal direction (the direction perpendicular to the feeding direction of the recording medium P). It may be. Bars arranged in the vertical direction are not affected by inertance, and bars arranged in the horizontal direction are affected by inertance. Therefore, if the width of each of the two printed bars is measured, the difference between the two indicates a width shift caused by inertance. The measurement for the test pattern may be performed by the user using a scanner or the like, and the result may be input to the image processing apparatus 2. Alternatively, a sensor built in the image forming apparatus 3 may read the test pattern printed in the image forming apparatus 3 as it is and output the read result to the image processing apparatus 2.

  Subsequently, the control unit 11 obtains information on the printing characteristics of the image forming apparatus 3 (S13), obtains the formation target image (S14), and arranges the barcode image B in the same manner as the processes of S1 to S3 described above. The direction is specified (S15). Thereafter, the control unit 11 determines a correction amount for the width w for each of the plurality of bars included in the barcode image B (S16). Specifically, the control unit 11 uses the information on the inertance level obtained in S12, the information obtained in S13 and S15, and the information on the width w of the bar to be corrected, as a correction amount determination table. The correction amount is determined with reference.

  FIG. 9 shows an example of a correction amount determination table used in this case. In the example of this figure, the description of the column corresponding to the horizontal arrangement not affected by inertance is omitted. As in FIG. 7, the vertical column of the table is information on printing characteristics, the arrangement direction of the barcode image B, and the width w of the bar to be corrected, and an inertance level is provided as a horizontal column. Yes. The correction amount is determined for each bar by a combination of these pieces of information.

  When the correction amount is determined, the control unit 11 corrects the bar with the correction amount determined in the same manner as in S5 (S17). Then, it is determined whether or not necessary correction has been performed for all the bars (S18). If there is a bar that has not been corrected, the process returns to S16 to determine and correct the correction amount for a new bar. When necessary correction is performed for all the bars, the corrected formation target image is output to the image forming apparatus 3 to form an image (S19).

  As described above, correction according to the degree of inertance actually occurring in the image forming apparatus 3 is performed.

  The embodiments of the present invention are not limited to those described above. For example, the image processing apparatus 2 may determine the correction amount by further using information relating to printing characteristics of the image forming apparatus 3 other than those described above and information relating to various printing conditions.

  DESCRIPTION OF SYMBOLS 1 Image forming system, 2 Image processing apparatus, 3 Image forming apparatus, 11 Control part, 12 Storage part, 13 Output part, 21 Image acquisition part, 22 Correction amount determination part, 23 Formation control part

Claims (7)

Image acquisition means for acquiring a code image including a plurality of lines and indicating information by the widths of the plurality of lines;
A correction amount determining means for determining a correction amount for the width of each of the plurality of lines according to a delay of the next discharge start after discharging the ink, which occurs when the image forming apparatus forms an image;
Forming means for causing the image forming apparatus to form the code image in which the width of each of the plurality of lines is corrected according to the correction amount;
An image processing apparatus comprising: A measurement result acquisition means for acquiring a measurement result of the displacement of the printing position due to the delay;
The image processing apparatus according to claim 1, wherein the correction amount determination unit determines a correction amount for a width of each of the plurality of lines according to the measurement result. The code image includes a plurality of lines having different widths,
The image processing apparatus according to claim 1, wherein the correction amount determination unit changes the correction amount according to a width of a line to be corrected. 4. The correction amount determination unit determines the correction amount for the width of each of the plurality of lines by using information related to printing characteristics of the image forming apparatus. 5. Image processing apparatus. The image processing apparatus according to claim 4, wherein the information related to printing characteristics of the image forming apparatus includes information on the number of ink ejection heads provided in the image forming apparatus. An image forming apparatus that forms an image by ejecting ink; and
An image processing apparatus for forming an image to be formed on the image forming apparatus;
Including
The image processing apparatus includes:
An image acquisition unit that includes a plurality of lines as the formation target image and acquires an image including a code image indicating information by the width of the plurality of lines;
A correction amount determining means for determining a correction amount for the width of each of the plurality of lines according to a delay of the next discharge start after the ink is discharged, which occurs when the image forming apparatus forms an image;
Forming means for causing the image forming apparatus to form the formation target image including the code image in which the width of each of the plurality of lines is corrected according to the correction amount;
An image forming system comprising: An image acquisition means for acquiring a code image including a plurality of lines and indicating information by a width of the plurality of lines;
A correction amount determining means for determining a correction amount for the width of each of the plurality of lines according to a delay of the next discharge start after the ink is discharged, which occurs when the image forming apparatus forms an image; and
Forming means for causing the image forming apparatus to form the code image in which the width of each of the plurality of lines is corrected according to the correction amount;
As a program to make the computer function as.

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