JP2012018498A - Printing control device and printing control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfy both reducing processing load and suppressing variation in printing results.SOLUTION: The printing control device comprises: a print data generation part for generating print data in which the occurrence and the non-occurrence of dots are set down for every pixel by applying a common image processing arranged as a processing for image data to image data to be printed; an acquisition part for acquiring characteristics information representing output characteristics specific to a designated printing device from the printing device; a regeneration part for regenerating print data by amending an amount of occurrence of dots set down by the print data based on the acquired characteristics information; and a provision part for providing the designated printing device with the regenerated print data.

Description

  The present invention relates to a print control apparatus and a print control method.

  A computer functioning as a host is connected to a printer, and the host generates print data and transmits it to the printer, and causes the printer to execute printing based on the print data. The printer ideally has output characteristics that meet the design criteria, but in reality, each printer has its own output characteristics. Specifically, the amount of ink ejected per drop is slightly different for each printer. Such variations in output characteristics cause variations in print results for each printer. Therefore, conventionally, when the host generates print data to be provided to the printer, it generates print data reflecting the output characteristics of the printer to which the print data is provided (print data specific to the printer of the supply destination). As a result, variations in printing results among printers were suppressed.

  There is also known a printer that executes editing (resolution conversion, layout and printing direction editing) on print data received from a host computer (see Patent Document 1).

Japanese Patent Laid-Open No. 6-91982

  When the host generates print data specialized for the printer of the data providing destination as described above, various conversion tables used in the process of generating the print data are recreated according to the output characteristics of the printer of the providing destination, Print data was generated using the converted conversion table. As described above, it is a heavy burden on the host to generate a conversion table that is different for each printer that provides data and thereby generate print data specialized for the printer that provides the data. In particular, when implementing distributed printing in which the host sends print data to multiple printers and prints to multiple printers, a different conversion table is generated for each printer and printing specialized for one printer is performed. It was necessary to repeat generation of data, and the processing burden was very heavy.

  The present invention has been made to solve the above-described problem, and a printing control apparatus capable of outputting a high-quality printing result to the printing apparatus while improving the efficiency of processing necessary for operating the printing apparatus, and A printing control method is provided.

  In one aspect of the present invention, the print control apparatus prescribes the occurrence or non-occurrence of dots for each pixel by performing common image processing prepared as processing for image data on the image data to be printed. A print data generation unit that generates print data; an acquisition unit that acquires characteristic information representing a specific output characteristic of the specified printing device from the printing device; and the print data based on the acquired characteristic information. Is configured to include a regeneration unit that regenerates print data by correcting the generation amount of dots defined by, and a providing unit that provides the regenerated print data to the designated printing apparatus. According to the present invention, image processing until print data defining generation / non-occurrence of dots for each pixel is generated from certain image data is common regardless of the printing apparatus. Thus, the dot generation amount is corrected according to the characteristic information for each printing apparatus, and the print data is regenerated. In other words, since it is not a configuration in which print data specialized for each printing apparatus is generated from the beginning in the process of generating print data from image data as in the past, processing until print data is finally provided to the printing apparatus The amount is reduced. In addition, the regenerated print data is provided to the designated printing device, and the printing process is executed by the printing device, so that a high-quality printing result in which variation among the printing devices is suppressed can be obtained.

  A storage unit that stores a correspondence relationship between the characteristic information and a correction table that defines a correction degree of the dot generation amount with respect to a plurality of characteristic information, and the regeneration unit includes a correction table corresponding to the acquired characteristic information May be acquired with reference to the storage unit, and the dot generation amount may be corrected using the acquired correction table. According to this configuration, it is possible to easily and accurately realize the correction of the dot generation amount according to the specified characteristic information of the printing apparatus.

  The common image processing is a color conversion table for converting the color system of image data into the color system of the color material used by the printing apparatus, and the image data is color-converted using the common color conversion table. It is good also as a structure including a process. The color conversion table is an example of the various conversion tables. According to this configuration, it is not necessary to repeat at least the color conversion process for each printing apparatus. For this reason, the amount of processing can be greatly reduced as compared to the case where print data is generated by performing color conversion corresponding to each printing apparatus using a color conversion table different for each printing apparatus as in the prior art. it can.

  The common image processing is a dot occurrence rate table for converting a gradation value into an occurrence rate of a plurality of dots having different sizes for each pixel of the image data after the color conversion. It is good also as a structure including the process which converts the image data after using the said color conversion. The dot occurrence rate table is an example of the various conversion tables. According to this configuration, it is not necessary to repeat the process of converting at least the color-converted image data into the occurrence rate of a plurality of dots having different sizes for each pixel for each printing apparatus. For this reason, the amount of processing can be greatly reduced as compared to the case where print data is generated by performing conversion corresponding to each printing device using a dot generation rate table that differs for each printing device, for example. it can.

  The technical idea of the present invention can be realized by means other than the printing control apparatus. For example, it is possible to grasp the invention of a print control method having each process corresponding to each part included in the above-described print control apparatus and a program that causes a computer to execute each function corresponding to each part included in the above-described print control apparatus. In addition, the print control method and the print control apparatus may be realized not only by a single apparatus but also by a plurality of apparatuses (for example, a computer and a plurality of printing apparatuses) in cooperation.

It is a figure which shows schematically the apparatus for implement | achieving a printing control method. 6 is a flowchart illustrating print control processing. It is a figure for demonstrating the relationship etc. between ID and a correction table.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1. FIG. 1 schematically shows an apparatus for realizing a printing control method according to this embodiment. Here, a plurality of printers 20 that can be used for distributed printing and a computer 10 that functions as a host for the printers 20 are shown. The computer 10 is connected to the printer 20 via a wired or wireless network N, and can control the printer 20 to cause the printer 20 to execute printing. Distributed printing includes various modes such as printing the same image on a plurality of printers 20, distributing each page of a file over a plurality of pages to a plurality of printers 20, and printing on each printer 20. .

  The printing control method is practically realized by the function of the computer 10. A CPU 12 included in the computer 10 reads a program stored in a memory such as a hard disk drive (HDD) 11 and executes a calculation according to the program while expanding the program in the RAM 13. The CPU 12 executes an operation according to a program (for example, the printer driver PD) on the OS, and controls the printer 20 via the network interface (I / F 14) or the network N. Therefore, the computer 10 can be regarded as a print control apparatus. A system including the computer 10 and the printer 20 can also be regarded as a print control apparatus. The computer 10 is connected to the display 40 via a video interface (I / F 15), and is connected to an operation unit 30 such as a keyboard and a mouse via an input interface (I / F 16).

  The printer driver PD performs a common image process prepared as a process for image data on the image data to be printed, thereby generating a print data generation unit that generates print data PRN that defines the occurrence or non-occurrence of dots for each pixel. PD1, an acquisition unit PD2 that acquires characteristic information representing the output characteristics unique to the designated printer 20, from the printer 20, and correcting the dot generation amount defined by the print data PRN based on the acquired characteristic information Each function of the regenerating unit PD3 that regenerates the print data and the providing unit PD4 that provides the regenerated print data PRN ′ to the designated printer 20 is realized.

2. FIG. 2 is a flowchart showing a print control process executed by the computer 10 in accordance with the printer driver PD. FIG. 2 schematically illustrates the structure of data generated and processed in each step together with each step in the flowchart.
In step S100, the computer 10 generates print data PRN by the function of the print data generation unit PD1. At the time of executing step S100, it is assumed that the computer 10 has received selection of image data representing an image to be printed, designation of the printer 20 used for printing, and the like through an operation of the operation unit 30 by the user. The user can also specify a plurality of printers 20.

  In step S100, first, the computer 10 acquires image data selected as a print target image from the HDD 11 or the like. The image data is, for example, data in which each pixel constituting the image is represented by a color system of red (R), green (G), and blue (B). Next, the computer 10 reads a color conversion lookup table (color conversion LUT) 11 a from the HDD 11. The color conversion LUT 11a is a color system (for example, cyan (C), magenta (M), yellow (Y), black (K), light cyan (Lc) of color materials (ink and toner) used by the printer 20 for image data. ), A light magenta (Lm) color system), which is referred to in order to convert the data into gradation values for each color of the input side color system (RGB) and the table on the output side. The color values (CMYKLcLm) are associated with gradation values for each color. The color conversion LUT 11a is generated on the assumption that the printer 20 that executes printing is a design standard printer, and is stored in the HDD 11 in advance. The computer 10 uses the color conversion LUT 11a to color-convert the selected image data into image data having a gradation value of CMYKLcLm for each pixel.

  Next, the computer 10 executes halftone processing on the image data after color conversion. In this case, the dot occurrence rate table 11b is read from the HDD 11. The dot occurrence rate table 11b uses one gradation value input to the table as an occurrence rate (for example, 0 to 100%) for each of a plurality of dots (for example, large dots, medium dots, and small dots) having different sizes. This table is stored in the HDD 11 in advance. The dot generation rate is a coverage by dots (ink droplets) per predetermined unit area. The computer 10 converts the gradation value for each pixel of the image data after the color conversion by the dot occurrence rate table 11b, and converts it to the occurrence rate for each of a plurality of dots having different sizes. Then, by executing a known halftone process (for example, a halftone process using a dither mask) for the occurrence rate of each of a plurality of dots for each pixel, any one of a large dot, a medium dot, and a small dot is performed for each pixel. Halftone data defining one occurrence (on) or no dot occurrence (off) is generated. Such conversion to the dot generation rate and halftone processing are performed for each color of the CMYKLcLm.

  Then, the computer 10 defines halftone data that defines dot on / off for each pixel as described above (which defines dot on or dot off of any one size for each pixel and color). Convert to a command format file that can be directly interpreted. This file corresponds to the print data PRN. As illustrated in FIG. 2, the print data PRN includes raster data R, a header H, and a footer F. The raster data R is a data portion that defines on / off of dots of each pixel constituting the image, and the header H is various information (for example, printing time) that needs to be notified to the printer 20 in addition to on / off of dots. Set value, print paper size, ink type, dot size, number of pixels, etc.). The printer 20 can print the print target image based on the print data PRN by receiving the print data PRN from the computer 10 and interpreting the print data PRN.

  However, the print data PRN generated in step S100 is data generated without considering the output characteristics of the printer 20 designated by the user. In other words, in step S100, the same print data PRN that represents the print target image is generated regardless of the designated printer 20. That is, in step S100, the same color conversion LUT 11a and the same dot occurrence rate table 11b are used in the process of generating the print data PRN, and the print data PRN is generated by applying the prepared common image processing to the image data. I can say that.

  In step 110, the computer 10 communicates with the printer 20 according to the designation on the network N, and acquires the ID held by the printer 20 according to the designation by the function of the acquisition unit PD2. ID is a kind of the characteristic information. The ID is, for example, the difference between the colorimetric value (color value) of the print result of the predetermined image by the printer 20 and the colorimetric value (reference color value) of the print result of the predetermined image printed on the printer serving as the design reference. A numerical value (ID) representing the degree of the above, generated in advance for each printer 20 and recorded in a predetermined memory in each printer 20 in advance. For example, when the printer 20 is an ink jet printer, the ink discharge amount (for example, the ink weight per dot of a predetermined size discharged from the print head) by the print head included in the printer 20 is determined by the print head of the design standard printer. It is slightly different from the ink discharge amount. Therefore, such a difference from the reference (ideal) of the ink discharge amount causes a difference in the colorimetric value, and as a result, each printer 20 has a different ID.

  However, the characteristic information for each printer that the computer 10 acquires from the printer 20 is not limited to the ID according to the difference in the colorimetric values as described above, and there are various kinds of information as long as the information represents the characteristic specific to each printer 20. Can be considered. For example, the computer 10 may acquire the ink weight ID held by the printer 20 in step S110. The ink weight ID is also a kind of the characteristic information. The ID is a numerical value representing a deviation of the ink discharge amount (the ink weight) by the print head provided in the printer 20 from the reference weight. Such an ID is acquired in advance when the print head is manufactured, and is recorded in a predetermined memory (or a memory mounted on the print head) in the printer 20 on which the print head is mounted.

The computer 10 transmits an ID acquisition request to the printer 20 specified above. Then, in response to the acquisition request, the printer 20 that has received the acquisition request reads out the ID recorded in the printer, and transmits the read ID to the computer 10. As a result, the computer 10 acquires the ID of the printer 20 according to the designation.
In step S120, the computer 10 acquires the correction table 11c corresponding to the acquired ID with reference to the HDD 11 by the function of the regeneration unit PD3, and uses the acquired correction table 11c to print the print data PRN. Corrects the amount of dots generated by.

Here, before describing step S120, the relationship between the ID and the correction table 11c will be briefly described with reference to FIG.
FIG. 3A illustrates three gray scale patterns PT1 to PT3 that are respectively printed by the first to third printers 20 having different ID values. Hereinafter, for convenience of explanation, the ID of the first printer 20 that has printed the grayscale pattern PT1 is ID1, the ID of the second printer 20 that has printed the grayscale pattern PT2 is ID2, and the third printer that has printed the grayscale pattern PT3. The ID of the printer 20 is expressed as ID3. The first printer 20 is a printer with a predetermined amount of ink ejection smaller than the design standard printer, the second printer 20 is a design standard printer, and the third printer 20 ejects ink more than the design standard printer. Assume that the printer has a predetermined amount.

  The gray scale patterns PT1 to PT3 are all printed based on exactly the same print data, and the number of dots p is the largest from the region (white) where the number of dots (K dots) p per unit area is the smallest (0). This is a gradient pattern in which the density gradually changes to a region (black). In FIG. 3B, the number of dots p (the number of dots p is a number with respect to the number of pixels PN (constant) constituting the unit area, p ≦ PN), and the densities (colorimetric results) of the gray scale patterns PT1 to PT3. Is illustrated by graphs G1 to G3. According to the graphs G1 to G3, the gray scale patterns PT1 to PT3 all increase in density as the number of dots p increases, but the density of the gray scale pattern PT1 (see graph G1) has a small ink discharge amount. Since it is printed by the first printer 20, it is generally lighter than the ideal gray scale pattern PT2 (see graph G2), and the density of the gray scale pattern PT3 (see graph G3) is the third amount with a large ink ejection amount. Since it is printed by the printer 20, the result is generally darker than the ideal gray scale pattern PT2.

  FIG. 3C illustrates the correction tables 11c generated based on the graphs G1 to G3, and the correction tables 11c1, 11c2, and 11c3 corresponding to ID1 to ID3 on a one-to-one basis. According to the graphs G1 and G2, the number of dots p required for realizing the predetermined density D by the design standard printer (second printer 20) is p1 (see the graph G2), but the same density D is the first density. The number of dots p required to be realized by the printer 20 is p2 (see graph G1). Therefore, a conversion relationship from the dot number p1 to the dot number p2 is obtained. In this way, the conversion relationship for each number of dots is acquired based on the graphs G1 and G2, and the conversion table 11c1 corresponding to the first printer 20, that is, ID1, is obtained by defining each conversion relationship thus acquired. (See FIG. 3C). Similarly, what defines the conversion relationship between the numbers of dots obtained based on the graphs G3 and G2 is the correction table 11c3 corresponding to the third printer 20 (ID3) (see FIG. 3C). In the correction table 11c2 corresponding to the second printer 20 (ID2), the number of input dots is equal to the number of output dots (see FIG. 3C). In the present embodiment, such a correspondence between the ID and the correction table 11c is obtained in advance for a plurality of IDs, and each ID and the correction table 11c corresponding to each ID are stored in the HDD 11. Therefore, the HDD 11 corresponds to a storage unit.

  Under such circumstances, in step S120, when an ID that matches the acquired ID is stored in the HDD 11, the computer 10 stores the ID in the HDD 11 corresponding to the matching ID. The correction table 11c is acquired. Further, when an ID that matches the acquired ID is not stored in the HDD 11, interpolation based on a plurality of correction tables 11c stored corresponding to a plurality of IDs approximate to the acquired ID is performed. The necessary correction table 11c is acquired by generating the correction table 11c corresponding to the acquired ID. When correcting the generated amount of dots defined by the print data PRN using the acquired correction table 11c, the computer 10 changes the number of dots for each predetermined area in the image, for example.

  In this case, the computer 10 expands the raster data R in the print data PRN in the command format and designates a region A having a constant area in the raster data R. Here, it is assumed that the area A is a rectangular area composed of the number of pixels PN. The computer 10 measures the number of pixels (number of dots) turned on in the region A, and inputs the measured number of dots into the acquired correction table 11c for conversion. Then, the number of dots defined by the raster data R in the region A is changed to be the number of dots after the conversion (dots are thinned out or dots are increased, see FIG. 2). The method of thinning or increasing the dots is not particularly limited, but basically, the pixels are thinned or increased so that the pixel positions where the dots are thinned out or added are not biased in the area A. The computer 10 designates all the areas in the raster data R once as the area A, and executes such a change in the number of dots for each designated area A.

  If there are multiple sizes of dots and ON / OFF of the dots is defined for each ink color as described above, the number of dots in a certain area is changed by the correction table 11c for each dot size and each ink color. To do. Of course, when the printer 20 has an ID for each ink color, the computer 10 acquires the ID for each ink color from the printer 20, and the correction table 11c for each ink color corresponding to the ID for each ink color. May be used to change the number of dots of each ink color. Further, when the printer 20 has an ID for each dot size, the computer 10 obtains an ID for each dot size from the printer 20, and a correction table for each size corresponding to the ID for each size. 11c may be used to change the number of dots for each size.

  In step S130, the computer 10 generates print data PRN ′ including the raster data R after the number of dots is changed by the function of the regeneration unit PD3 (regeneration of print data). In the print data PRN generated in step S100 and the print data PRN ′ regenerated in step S130, the header H and the footer F are basically the same, and the number of dots defined by the raster data R is different ( However, the case where the ID of the designated printer 20 indicates a design standard printer is excluded). Therefore, only the raster data R is to be regenerated, and the header H and footer F are the same as those of the print data PRN.

  In step S140, the computer 10 provides (transmits) the print data PRN ′ to the designated printer 20 via the network N by the function of the providing unit PD4. The printer 20 receives the print data PRN ′ from the computer 10, interprets the print data PRN ′, and prints the print target image based on the print data PRN ′. Such print data PRN ′ has a dot generation amount (the number of dots) so as to suppress variations in print results due to variations in output characteristics unique to the printer 20 that receives the print data PRN ′ (excess or deficiency in ink discharge amount). The corrected data. When a plurality of printers 20 are designated by the user, the computer 10 acquires an ID from each of the specified printers 20 (step S110), and each correction table 11c corresponding to each acquired ID. Then, the dot generation amount of the print data PRN is corrected, and the print data PRN ′ to be provided to each of the plurality of printers 20 according to the designation is regenerated (steps S120 and S130), and each regenerated print data PRN ′ is Each print data PRN ′ is provided to the corresponding designated printer 20 (step S140).

3. Summary As described above, according to the present embodiment, the computer 10 first performs various conversion processes on image data using the common color conversion LUT 11a and the dot occurrence rate table 11b prepared in advance regardless of the printer 20 designated by the user. Then, print data PRN that does not reflect the output characteristics of the printer 20 according to the designation is generated. Then, the print data PRN ′ is generated by correcting the dot generation amount defined by the print data PRN with the correction table 11c corresponding to the ID of the printer 20 related to the specification, and the print data PRN ′ is set as the specification. The printer 20 is provided. Accordingly, when the printer 20 performs printing based on the print data PRN ′, a high-quality print result is obtained in which variations in the print result due to variations in the output characteristics of the printer 20 from the design standard are suppressed.

  In the process of generating the print data PRN as described above, no correction processing (correction processing of the color conversion LUT 11a or the dot occurrence rate table 11b) according to the output characteristics of the designated printer 20 as in the past is performed. That is, conventionally, when print data is provided to each designated printer 20, correction of the color conversion LUT or dot generation rate table, and conversion processing for image data using the corrected color conversion LUT or dot generation rate table are performed. The process is repeatedly executed according to the number of printers 20 to be provided. However, according to the present embodiment, such a repetition is not necessary, so that the processing required until the print data is provided to the printer 20 as the provision destination is greatly improved in efficiency. According to the present embodiment, since the print data PRN representing the print target image can be shared, the processing amount reduction effect according to the present embodiment is particularly exhibited when executing distributed printing in which a plurality of printers 20 print the print target image. Is done.

DESCRIPTION OF SYMBOLS 10 ... Computer, 11 ... HDD, 11a ... Color conversion LUT, 11b ... Dot generation rate table, 11c, 11c1, 11c2, 11c3 ... Correction table, 12 ... CPU, 13 ... RAM, 20 ... Printer

Claims (5)

A print data generation unit that generates print data that defines the occurrence or non-occurrence of dots for each pixel by performing common image processing prepared as processing for image data on the image data to be printed;
An acquisition unit that acquires characteristic information representing unique output characteristics of the designated printing device from the printing device;
A regenerator that regenerates print data by correcting the amount of dots generated by the print data based on the acquired characteristic information;
A providing unit for providing the regenerated print data to the designated printing device;
A printing control apparatus comprising: A storage unit that stores a correspondence relationship between the characteristic information and a correction table that defines a correction degree of the amount of generated dots with respect to a plurality of characteristic information;
The regenerating unit acquires a correction table corresponding to the acquired characteristic information with reference to the storage unit, and corrects a dot generation amount using the acquired correction table. The printing control apparatus according to 1.   The common image processing is a color conversion table for converting the color system of image data into the color system of the color material used by the printing apparatus, and the image data is color-converted using the common color conversion table. The printing control apparatus according to claim 1, further comprising a process.   The common image processing is a dot occurrence rate table for converting a gradation value into an occurrence rate of a plurality of dots having different sizes for each pixel of the image data after the color conversion. The print control apparatus according to claim 3, further comprising a process of converting the image data after the color conversion by using. A print data generation step for generating print data that defines the occurrence or non-occurrence of dots for each pixel by performing common image processing prepared as processing for image data on the image data to be printed;
An acquisition step of acquiring characteristic information representing a specific output characteristic of the designated printing apparatus from the printing apparatus;
A regeneration step of regenerating the print data by correcting the amount of dots generated by the print data based on the acquired characteristic information;
A providing step of providing the regenerated print data to the designated printing device;
A printing control method comprising: