JP2005007753A - Color image output device and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a color printer to output an image processed on a screen processing condition nearly equivalent to a final print quality. <P>SOLUTION: The screen condition decision means 21 obtains a multi-value image data and a processing condition to subject the multi-value image data to the screen processing. An image output section 202 judges whether the image based on the binary image data generated by subjecting the multi-value image data to the screen processing according to the processing condition can be output or not, using the processing condition. When the image is judged possible to be output, said processing condition is used as an implement condition. When the image is judged impossible to be output, said processing condition is changed so that the image output part 202 outputs the binary image data exhibiting an image allowed to be output. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for outputting image data created for a certain image output device to another image output device having different output characteristics.
[0002]
[Prior art]
Conventionally, as a method of color proofing for printing, a method using a film prepared for plate making has been the mainstream. However, with the widespread use of CTP (Computer to Plate), which performs plate making directly from image data using a digital plate making machine, there is an increasing demand for outputting proofs using binary image data for plate making and using them for color proofing. It was. Although there is DDCP (Direct Digital Color Proof) as a technology that meets this demand, there is a problem that the user's financial burden becomes heavy because an expensive dedicated machine is used.
[0003]
On the other hand, it is convenient if the user can input image data to a color printer already owned and output a proof. However, color printers are generally not suitable for color proofing because their color output characteristics are different from those of a printing machine used in actual printing. In order to solve this problem, color correction is performed to adjust image data to be supplied to the color printer so that the color tone of the output image from the color printer matches the color tone of the printed matter of the main print. Specifically, first, the color measurement patch image data is input to the color printer, and the color measurement patch image is output. Next, the side color value of the colorimetric patch output from the color printer is obtained using a spectrophotometer. This side color value is compared with the side color value of the colorimetric patch printed by the printing machine, and a color conversion processing coefficient used for color conversion to be applied to image data given to the color printer is obtained. Color conversion of the image data is performed using the processing coefficients for color conversion, and the image data having the same color tone as that printed by the printing press is output from the color printer by giving the color converted image data to the color printer. Is done. In this way, color proofing using a proof printed by a color printer becomes possible.
[0004]
Various techniques have been proposed for color correction of binary image data. In the technique described in Patent Document 1, binary image data is converted into multi-values, image processing such as color correction is performed, error diffusion is performed, and binary image data is output. The correction is realized. In the technique described in Patent Literature 2, binary image data is subjected to soft focus filter processing to be multi-valued, color correction of the multi-value image data is performed, error diffusion is performed, and binary image data is output. . As a result, the color correction with the halftone dot information remaining is realized.
[0005]
[Patent Document 1]
Japanese Patent No. 2877356
[Patent Document 2]
International Publication No. 02/30103 Pamphlet
[0006]
[Problems to be solved by the invention]
By the way, in the above prior art, the color printer may not be able to output an image according to the screen processing conditions depending on the processing conditions of the screen processing performed when generating the binary image data for plate making. For example, in general, the number of screen lines that can be output by a color printer is 200 lpi (line per inch) or less, and when binary image data for plate making is generated with a screen line number exceeding this, the color printer uses that as an image. Cannot output.
[0007]
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to enable output of a proof print by a color printer even when screen processing conditions not supported by the color printer are given. There is.
[0008]
[Means for Solving the Problems]
In order to solve the above-described problem, the present invention acquires an image output unit that outputs an image based on binary image data, multi-value image data, and a processing condition for screen processing the multi-value image data. The image output unit can determine whether or not the image output unit can output an image based on the binary image data generated by screen processing the multi-valued image data according to the processing condition, and can output the image. If it is determined that the processing condition is an implementation condition, and if it is determined that output is not possible, the processing condition is output so that binary image data representing an image that can be output by the image output unit is output. Screen condition determining means for changing the processing conditions to be an implementation condition, raster processing means for converting the multi-valued image data into a raster data format and outputting it, and color for the multi-valued image data in the raster data format After having been subjected to conversion, to provide a color image output apparatus characterized by comprising a screen processing means for generating binary image data to the screen processing according to the execution condition.
[0009]
Further, according to the present invention, the multi-valued image data and processing conditions for screen processing the multi-valued image data are acquired by the computer device, and the multi-valued image data is generated by screen processing according to the processing conditions. Whether or not the image output unit can output an image based on the binary image data is determined using the processing condition. When it is determined that the image can be output, the processing condition is set as the execution condition and can be output. If it is determined that the processing condition is not, a screen condition determination step that changes the processing condition so as to output binary image data representing an image that can be output by the image output unit, and sets the processing condition as an execution condition; A raster processing step for converting multi-valued image data into a raster data format and outputting it, color-converting the multi-valued image data in the raster data format, and then performing a script according to the execution conditions. It provides a program for executing a screen process step of generating the binary image data down process.
[0010]
According to the present invention, the screen condition determining means acquires multi-value image data and a processing condition for screen processing the multi-value image data, and generates the multi-value image data by performing screen processing according to the processing condition. Whether or not the image output unit can output an image based on the binary image data that has been output is determined using the processing condition. If it is determined that the image can be output, the processing condition is set as an execution condition, and output is performed. When it is determined that the processing is not possible, the processing condition is changed to be an execution condition so that binary image data representing an image that can be output by the image output unit is output. Next, raster processing means converts the multi-value image data into a raster data format and outputs it. Next, the screen processing means performs color conversion on the multi-value image data in the raster data format, and then performs screen processing according to the execution conditions to generate binary image data.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
(1. First embodiment)
(1-1. Configuration)
FIG. 1 is a diagram showing a configuration according to the first embodiment of the present invention. In the configuration shown in FIG. 1, a client device 10, a color printer 20, a RIP server 40 and a plate making machine 50 are connected via a LAN (Local Area Network) 2.
[0012]
The client device 10 is a computer having a normal hardware configuration, and exchanges data with other devices via the LAN 2. The client device 10 displays an input screen that prompts the user to input the file name, processing conditions, etc. of the image data, and the operator can input the data using a keyboard and a mouse (not shown).
[0013]
The RIP server 40 acquires vector data described in a page description language such as Post Script, converts the vector data into raster data, and performs screen processing to generate binary image data for plate making. The RIP server 40 in this embodiment can generate binary image data for plate making with a resolution of 2400 dpi (dot per inch). It is also possible to select other resolutions. The binary image data for plate making generated by the RIP server 40 is, for example, image data in a TIFF (Tagged Image File Format) format, and includes or accompanies screen processing conditions and resolution information.
[0014]
The color printer 20 is used for acquiring binary image data for plate making created by the RIP server 40 and outputting a proof.
In the present embodiment, the proof printing binary image data outputted from the RIP server 40 is proofread using this proof print.
[0015]
The plate making machine 50 is a digital plate making machine that receives the calibrated binary image data for plate making from the RIP server 40, and based on this, directly exposes the plate material to produce a printing plate.
The printing machine 60 performs multicolor printing using the printing plate produced by the plate making machine 50.
[0016]
Next, the configuration of the color printer 20 will be described. As shown in FIG. 1, the color printer 20 includes a controller 201 and an image output unit 202. Here, the image output unit 202 is an electrophotographic image output apparatus that outputs an image under the control of the controller 201. The image output unit 202 can output an image having the same resolution as the RIP server 40 (here, 2400 dpi). Further, it is assumed that the image output unit 202 does not support AM (Amplitude Modulation) screen processing with a high line number exceeding 200 lpi (line per inch).
[0017]
The configuration of the controller 201 is shown in FIG. A CPU (Central Processing Unit) 30 executes a program stored in a ROM (Read Only Memory) 31 to perform control for generating a proof print by the image output unit 202. A RAM (Random Access Memory) 32 is used as a work area at that time.
[0018]
The transmission / reception unit 33 transmits / receives data to / from other devices connected to the LAN 2 under the control of the CPU 30.
The storage means 34 is a mass storage device such as a hard disk drive.
The screen condition determination unit 21, the raster processing unit 22, and the screen processing unit 23 are software modules that are executed by the CPU 30 to generate a proof. Hereinafter, these functions will be described.
[0019]
The screen condition determining means 21 is a module that acquires screen processing conditions (screen type, screen line number) and determines whether an image based on the image data generated according to the screen processing conditions can be output by the color printer 20. is there.
[0020]
The raster processing means 22 is a module that converts multi-value image data in vector data format into multi-value image data in a raster data format having a resolution that can be output by the color printer 20 and outputs the converted data.
[0021]
The screen processing unit 23 performs color conversion on the multi-value image data in the raster data format using the color conversion coefficient, and then performs screen processing according to the execution condition received from the screen condition determination unit 21 to obtain binary image data for the printer. Is a module that outputs Here, the color conversion coefficient is obtained in advance based on the difference in the output characteristics of the color printer 20 with respect to the output characteristics of the printing press 60, and is stored in the storage unit 34. The color conversion coefficient can be created using, for example, a method disclosed in Japanese Patent Application Laid-Open No. 2002-152543.
Note that the above modules may be configured by hardware, and the CPU 30 may control these modules to advance the process for proof printing output.
[0022]
(1-2. Operation)
The operation realized by the above configuration will be described. In the present embodiment, it is assumed that the color printer 20 does not support AM (Amplitude Modulation) screen processing with a high line count exceeding 200 lpi (line per inch). Multi-value image data D1 for obtaining a proof is stored in the storage means 34 in advance.
[0023]
First, when the operator inputs the file name and screen processing conditions of the multi-value image data D1 for obtaining a proof to the client device 10, an output instruction for the multi-value image data D1 is sent from the client device 10 to the color printer 20. Sent to.
[0024]
When the CPU 30 of the color printer 20 receives an output instruction from the client device 10 via the transmission / reception unit 33, the CPU 30 executes a program whose flow is shown in FIG.
First, the CPU 30 receives the multi-value image data D1 and the screen processing conditions from the client device 10 (step S11), and delivers the screen processing conditions to the screen condition determining means 21.
Next, the CPU 30 makes a determination regarding the acquired screen processing condition. First, the CPU 30 determines the screen type (step S12). If the screen type is an AM screen, the CPU 30 determines the number of screen lines (step S14). Here, when the number of screen lines is 200 lpi or less, the multivalued image data D1 can be output by the image output unit 202, and therefore raster processing and screen processing may be performed without changing the screen conditions. Therefore, in this case, the CPU 30 delivers the multi-value image data D1 to the raster processing means 22. Processing (after step S16) after the multi-value image data D1 is transferred to the raster processing means 22 will be described later.
[0025]
On the other hand, if it is determined in step S12 that the screen type is not an AM screen, the screen type is changed to an FM screen by error diffusion (step S13).
If it is determined in step S12 that the screen type is AM and the number of screen lines exceeds 200 lpi in step S14, the number of screen lines is changed to 200 lpi (step S15).
As described above, the processing conditions for the screen processing applied to the multi-value image data D1 are determined. The determined processing conditions are referred to herein as execution conditions.
[0026]
In step S <b> 16, the CPU 30 delivers the multivalued image data D <b> 1 to the raster processing means 22. When the multi-value image data D1 is in the vector data format, the raster processing means 22 converts the multi-value image data D1 into multi-value image data D2 in a raster data format having a resolution that can be output by the color printer 20, and outputs the converted data. On the other hand, when the multi-value image data D1 is in the raster data format, the multi-value image data D1 is converted into multi-value image data D2 having a resolution that can be output by the color printer 20 and output.
[0027]
Next, the CPU 30 delivers the multi-value image data D2 to the screen processing means 23. The screen processing unit 23 performs color conversion on the multi-valued image data D2 using the color conversion coefficient, and then performs screen processing according to the execution condition received from the screen condition determining unit 21, and outputs the binary image data D3 for the printer. To do. In this operation example, the image output unit 202 is a binary image that has been subjected to screen processing under the condition that the screen type is an AM screen or an error diffusion FM screen, the screen line number is 200 lpi or less, and the screen angle is an arbitrary angle. Any data can be output. Accordingly, the screen processing means 23 selects the one closest to the screen processing conditions applied to the plate-making binary image data D1 within this range, and performs the screen processing of the multi-value image data D2 according to the selected conditions. It is.
[0028]
When the printer binary image data D3 is generated by the screen processing means 23 (step S17), the CPU 30 delivers the generated printer binary image data D3 to the image output unit 202. The image output unit 202 outputs a proof print based on the binary image data D3 for the printer.
[0029]
According to the present embodiment, even when the condition of the screen processing applied to the multi-value image data D1 is a condition that cannot be output by the image output unit 202, the multi-value image data D1 is input to the color printer 20 and printed. An image can be output under screen processing conditions similar to a printed matter by the machine 60.
[0030]
(2. Second Embodiment)
(2-1. Configuration)
FIG. 4 is a diagram showing a configuration according to the second exemplary embodiment of the present invention. Constituent elements common to the first embodiment are denoted by the same reference numerals. The differences from the configuration according to the first embodiment are as follows.
As shown in FIG. 4, the color printer 20a includes a controller 201a and an image output unit 202. As shown in FIG. 5, the controller 201a has the same configuration as the controller 201 in the first embodiment except that the controller 201a includes a transfer unit 24. The transfer unit 24 is a module that determines whether or not the screen processing condition changed so as to be output by the image output unit 202, that is, the execution condition is a condition that can be executed by the screen processing unit 23 of the color printer 20a. is there. When it is determined that the screen processing unit 23 cannot execute the data, the execution condition and the multi-value image data D1 are transferred to the RIP server 40 via the transmission / reception unit 33. The binary image data D2 generated by screen processing by the RIP server 40 is supplied to the color printer 20a.
[0031]
(2-2. Operation)
The operation realized by the above configuration will be described. Multi-value image data D1 for obtaining a proof is stored in the storage means 34 in advance.
[0032]
First, when the operator inputs the file name and screen processing conditions of the multi-value image data D1 for obtaining a proof to the client device 10, an output instruction for the multi-value image data D1 is sent from the client device 10 to the color printer 20a. Sent to.
[0033]
When the CPU 30 of the color printer 20a receives an output instruction from the client device 10 via the transmission / reception unit 33, the CPU 30 executes a program whose flow is shown in FIG.
The operations from step S11 to S15 are the same as those in the first embodiment. In step S21, the CPU 30 determines whether or not the execution condition determined through step S14 or step S15 is a condition that the screen processing means 23 can execute. If it is determined that the screen processing unit 23 can execute the process, the process proceeds to step S16. On the other hand, if it is determined by the screen processing means 23 that the execution is not possible, the execution conditions, the multi-value image data D1, and the color conversion coefficient are delivered to the RIP server 40 (step S22).
[0034]
In the RIP server 40, when the multi-value image data D1 supplied from the color printer 20a is vector data, the multi-value image data D1 is converted into raster data, and multi-value image data having a resolution that can be output by the color printer 20a. Convert to D1a and output. On the other hand, when the multi-value image data D1 is raster data, the multi-value image data D1 is converted into multi-value image data D1a having a resolution that can be output by the color printer 20a and output.
[0035]
Next, the RIP server 40 performs color conversion on the multi-value image data D1 or D1a using the color conversion coefficient received from the color printer 20a. Then, the RIP server 40 performs screen processing on the multi-valued image data after color conversion in accordance with the execution conditions received from the color printer 20a, and generates binary image data D2.
The binary image data D2 generated by the RIP server 40 is supplied from the RIP server 40 to the color printer 20a.
[0036]
According to the present embodiment, even when the screen processing condition applied to the multi-value image data D1 is a condition that the image output unit 202 cannot output, the multi-value image data D1 is input to the color printer 20a and printed. An image can be output under screen processing conditions similar to a printed matter by the machine 60. Even in the case of screen processing conditions that cannot be executed by the color printer, by causing the RIP server to perform screen processing, it is possible to output an image with screen processing conditions close to a printed matter by the printing press 60.
[0037]
(3. Third embodiment)
(3-1. Configuration)
FIG. 7 is a diagram showing a configuration according to the second exemplary embodiment of the present invention. Constituent elements common to the first embodiment are denoted by the same reference numerals. The differences from the configuration according to the first embodiment are as follows.
As shown in FIG. 7, the color printer 20b includes a controller 201b and an image output unit 202. As shown in FIG. 8, the controller 201b has the same configuration as that of the controller 201 in the first embodiment except that it includes a screen condition changing unit 25. The screen condition changing unit 25 is a module that changes the screen processing conditions so that the image output unit 202 can output the screen conditions.
[0038]
(3-2. Operation)
The operation realized by the above configuration will be described. Multi-value image data D1 for obtaining a proof is stored in the storage means 34 in advance.
[0039]
First, when the operator inputs the file name and screen processing conditions of the multi-value image data D1 to obtain a proof to the client device 10, an output instruction for the multi-value image data D1 is sent from the client device 10 to the color printer 20b. Sent to.
[0040]
When the CPU 30 of the color printer 20b receives an output instruction from the client device 10 via the transmission / reception unit 33, the CPU 30 executes a program whose flow is shown in FIG.
The operations from step S11 to S14 are the same as those in the first embodiment. In step S <b> 31 to step S <b> 38, the screen processing condition acquired from the client device 10 is delivered to the screen condition changing unit 25. In the screen condition changing means 25, the CPU 30 determines whether or not the screen processing conditions are conditions that can be executed by the screen processing means 23. If it is determined that the screen processing conditions are not executable, the CPU 30 changes the conditions to be executable.
[0041]
In step S <b> 31, the CPU 30 determines whether the screen line number acquired from the client device 10 can be executed by the screen processing unit 23. If it can be executed, the process proceeds to step S33 without changing the number of screen lines. On the other hand, if it is not feasible, the line number is changed to the closest number to the screen line number acquired from the client device 10 within the range executable by the screen processing unit 23, and the process proceeds to step S33. For example, when the number of lines that can be executed by the screen processing unit 23 is 150 lpi and 190 lpi, and the number of screen lines acquired from the client device 10 is 175 lpi, the number is determined to be 190 lpi.
[0042]
In step S <b> 33, the CPU 30 determines whether the screen angle acquired from the client device 10 can be executed by the screen processing unit 23. If it can be executed, the process proceeds to step S35 without changing the screen angle. On the other hand, if it is not feasible, the angle is changed to the closest angle to the screen angle acquired from the client device 10 within the range feasible by the screen processing means 23, and the process proceeds to step S35.
[0043]
In step S <b> 35, the CPU 30 determines whether the spot shape acquired from the client device 10 can be executed by the screen processing unit 23. If it can be executed, the process proceeds to step S37 without changing the spot shape. On the other hand, if it is not feasible, the shape is changed to the shape closest to the spot shape acquired from the client device 10 within the range feasible by the screen processing means 23, and the process proceeds to step S37.
[0044]
In step S <b> 37, the CPU 30 determines whether or not the screen family acquired from the client device 10 can be executed by the screen processing unit 23. A screen family is an option item that can be specified when performing screen processing. For example, in the case of an AM screen, it is possible to specify that a rational tangent screen which is a kind of AM screen is used. If it can be executed, the process proceeds to step S16 without changing the screen family. On the other hand, if not executable, the screen family 23 is changed to an executable screen family and the process proceeds to step S16.
As described above, the processing conditions for the screen processing applied to the multi-value image data D1 are determined.
The processes after step S16 are the same as those in the first embodiment.
[0045]
According to the present embodiment, even when the condition of screen processing applied to the multi-value image data D1 is a condition that the image output unit 202 cannot output, the multi-value image data D1 is input to the color printer 20b and printed. An image can be output under screen processing conditions similar to a printed matter by the machine 60. Even in the case of a screen processing condition that cannot be executed by a color printer, an image subjected to screen processing close to a printed matter by the printing press 60 can be obtained by changing to the closest condition within the executable range of the color printer. It becomes possible to output.
[0046]
(4. Modifications)
The present invention is not limited to the form described above, and can be implemented in various forms. For example, the embodiment described above can be modified as follows.
[0047]
The present invention may be modified such that the above-described program executed by the CPU is stored in an external server, and this program is downloaded from an external server via a communication network such as the Internet. In addition, the program is stored in an external server, multi-value image data is transmitted to the server via a communication network, and the above-described program is executed by the server to generate binary image data for a printer. The present invention may be modified.
[0048]
For the color printer, the present invention may be modified to use, for example, an ink jet type color printer other than the electrophotographic system.
The multi-value image data D1 may be raster data. Further, when the output instruction is transmitted from the client device 10 to the printer 20, the multi-value image data D1 may be transmitted simultaneously.
[0049]
【The invention's effect】
According to the present invention, an image processed under a screen processing condition close to that of a printing machine for full printing can be output by a color printer.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration according to a first embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a controller 201 according to the same embodiment.
FIG. 3 is a flowchart showing a flow of processing executed by a controller 201 according to the embodiment;
FIG. 4 is a diagram illustrating a configuration according to a second embodiment of the present invention.
FIG. 5 is a diagram showing a configuration of a controller 201a according to the same embodiment.
FIG. 6 is a flowchart showing a flow of processing executed by the controller 201a according to the same embodiment;
FIG. 7 is a diagram showing a configuration according to a third embodiment of the present invention.
FIG. 8 is a diagram showing a configuration of a controller 201b according to the same embodiment.
FIG. 9 is a flowchart showing a flow of processing executed by the controller 201b according to the embodiment;
[Explanation of symbols]
2 ... LAN, 10 ... client PC, 20 ... color printer, 40 ... RIP server, 50 ... plate making machine, 60 ... printing machine, 201 ... controller, 202 ... input / output unit, 21 ... screen condition determining means, 22 ... raster processing Means, 23 ... Screen processing means, 31 ... ROM, 32 ... RAM, 33 ... Transmission / reception unit, 34 ... Storage means

Claims (7)

An image output unit for outputting an image based on the binary image data;
An image based on binary image data generated by obtaining multi-value image data and a processing condition for screen-processing the multi-value image data and screen-processing the multi-value image data according to the processing condition Whether or not the output unit can output is determined using the processing condition. When it is determined that output is possible, the processing condition is set as an implementation condition. When it is determined that output is not possible, the processing condition is determined. A screen condition determining means that changes the processing condition so as to output binary image data representing an image that can be output by the image output unit.
Raster processing means for converting the multi-value image data into a raster data format and outputting the raster data;
A color image output apparatus comprising: a screen processing unit that performs color conversion on the multi-valued image data in the raster data format, and then performs screen processing according to the execution condition to generate binary image data. It is determined whether or not the screen processing means can execute the screen processing according to the execution condition. If the screen processing means is not executable, the screen processing according to the execution condition and the multivalued image data can be executed. 2. The color image output apparatus according to claim 1, further comprising transfer means for transferring the binary image data generated by being transferred to an appropriate apparatus and subjected to screen processing by the apparatus. Screen condition changing means for determining whether or not the screen processing means can execute the screen processing according to the execution condition, and if not, can change the execution condition so that the screen processing means can be executed. The color image output apparatus according to claim 1, further comprising: The color image output apparatus according to claim 3, wherein the screen condition changing unit determines a screen processing condition according to a predetermined priority order. The color image output device according to claim 1, wherein the color image output device is a color printer. 6. The color image output apparatus according to claim 5, wherein the color printer is an electrophotographic color printer. Computer equipment,
Obtain multivalued image data and processing conditions for screen processing the multivalued image data, and output an image based on the binary image data generated by screen processing the multivalued image data according to the processing conditions The processing condition is used to determine whether or not the output is possible. When it is determined that the output is possible, the processing condition is set as the implementation condition. When it is determined that the output is not possible, the processing condition is set. A screen condition determining step in which the processing condition is changed so as to output binary image data representing an image that can be output by the image output unit;
A raster processing step of converting the multi-value image data into a raster data format and outputting the raster data;
A program for executing a screen processing step of generating binary image data by performing screen processing in accordance with the execution conditions after color conversion is performed on multi-value image data in the raster data format.

Images