JP2012086437A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a desired printed matter conforming to the specification of Collate/Uncollate.SOLUTION: An image forming apparatus analyzes input image data to generate drawing data. The image forming apparatus performs the density correction of the drawing data by using density correction data of an image. In the image forming apparatus, it is possible to set whether or not to print the image data in copy units (Collate/Uncollate), when the image data of a plurality of pages are printed by a plurality of copies. When shifted to a predetermined image quality adjusting mode in the midst of image forming, the image forming apparatus determines whether or not to interrupt image forming to perform the density correction again conforming to a set state by a Collate/Uncollate setting means. For example, when finishing the print of the first sheet of a second page after finishing the print of a first page in Uncollate setting, it is defined as a situation that new calibration data by image quality adjustment are generated (S112). In such a case, all the sheets are printed to a third page without stopping the print, and then the print is completed (S113).

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus that generates a bitmap image from page description language data transmitted from an information processing apparatus and forms an image.

  An image forming apparatus such as a printer that is connected to a host computer such as a personal computer, processes print data transmitted from the host computer, and performs printing (image formation) is generally used. For example, the host computer is installed with image generation software such as word processing software and paint software, and a printer driver that sends the generated image of a document, painting, etc. to an image processing apparatus to form an image on a recording sheet. Has been.

  The image generated by the host computer is converted by the printer driver into data (PDL data) in which a command for image formation is described in a page description language, and the converted PDL data is transmitted to the image forming apparatus. Upon receiving the PDL data, the image forming apparatus analyzes the commands included in the received PDL data and generates intermediate data including information indicating the drawing object and the attributes of the drawing object (type, coordinates, color, etc. of the drawing object). Raster image data (bitmap image) is generated by rendering the generated intermediate data. Further, the image forming apparatus forms an image on a recording sheet based on the generated raster image data. At this time, the image forming apparatus forms an image on the recording sheet while conveying the recording sheet in a predetermined direction.

  On the other hand, there is a system in which a printer driver generates intermediate data based on PDL data and transmits the generated intermediate data to an image forming apparatus. In this case, it is not necessary for the image forming apparatus to generate intermediate data, and the image forming apparatus can generate raster image data and form an image on a recording sheet by rendering the received intermediate data.

  In the image forming apparatus, raster image data generated from PDL data or the like can be stored and repeatedly printed. In this case, there arises a problem that the color characteristics of the raster image data stored initially are different due to a change in density characteristics of a print engine that forms a toner image on a photosensitive member and transfers the toner image onto a recording sheet. Specifically, there are changes in the output image due to changes in temperature, humidity, etc., or changes in the image due to deterioration of consumable parts such as toner on the photosensitive drum and toner cartridge.

There is an image forming apparatus that performs density control in order to correct such a change in density characteristics and supply a stable image. For example, the current density characteristic is measured by the image forming apparatus, and density correction information is generated according to the measurement result. Then, density correction processing is performed when generating intermediate data based on the PDL data, and the intermediate data is stored in the memory. When the same printing is repeated, the intermediate data is read and printed.
However, in the method as described above, intermediate data that has been subjected to density correction processing is repeatedly used, so that it cannot cope with changes in density correction information over time. In this case, there is a difference between the current density correction information and the density correction information when the intermediate data is generated, and the image density may not be appropriate.

In order to cope with this, for example, Patent Document 1 discloses a technique of measuring density characteristics during printing and generating intermediate data again when a difference of a certain level or more is detected.
Here, when the generated intermediate data is stored, the density correction data used to generate the intermediate data is also stored. When the stored intermediate data is reused to form an image, the density correction data stored together with the intermediate data is compared with the current density correction data. Print data is read, intermediate data is generated again, and raster image data is generated. As a result, if there is a density shift while the image formation of the intermediate data once formed is repeated many times, the intermediate data subjected to density correction can be formed again, so that the print result (color It is said that it is possible to avoid the problem that the difference is greatly different.
Hereinafter, the intermediate data generation based on the density correction data and the raster image data generation process based on the intermediate data are referred to as RIP (Raster Image Processor), and the intermediate data is generated again based on the comparison of the density correction data. A process for generating raster image data will be described as re-RIP.

Japanese Patent Laid-Open No. 2005-22298

  In an image forming apparatus such as a printer that performs printing (image formation), there is Collate / Uncollate setting as a setting condition when performing printing. This setting specifies whether or not to print in multiple units when the print job instructs to print multiple copies of the original image of multiple pages. Collate specifies printing in units of copies, and Uncollate Specifies non-copy printing. Collate / Uncollate setting is also called sort / group printing.

  As in Patent Document 1, when the current density correction data is compared with the current density correction data, and the intermediate data is regenerated using the current density correction data when there is a difference of a predetermined level or more, Collate / Depending on the Uncollate setting conditions, if the same processing is simply performed, a printed matter different from the output result expected by the user during Uncollate may be obtained. The reason for this will be described below.

  FIG. 15 is a diagram for explaining an example of the printing order of image data according to Collate / Uncollate setting. For example, it is assumed that the image data of the document instructed by the print job is 1 to 3 pages and the number of copies is three. Here, when Collate is set, printing in the page order of 1, 2, 3 is repeated three times. When Uncollate is set, 1 page is printed in 3 copies, 2 pages are 3 copies, and 3 pages are printed in 3 copies.

FIG. 16 is a diagram for explaining an example of a problem in conventional re-RIP. When three copies of original image data of 3 pages are printed with Uncollate setting, re-RIP (reproduction of intermediate data) based on density correction data is performed. The state when the process is performed is shown.
The image forming apparatus that has received the print data executes RIP at time t1 (S401). Here, density correction data (calibration data) at time t1 is acquired, density correction processing is performed on the image data, intermediate data is generated, rasterized, and printing is started. Since the setting is Uncollate, the printing order is 1, 1, and 1 pages. For example, three copies are designated as the number of print copies.

  After printing the first page, the second page is printed in the order of 2, 2, and 2. However, when the first page of the second page is finished, a new calibration by image quality adjustment is performed. It is assumed that the action data is created at time t2 (S402). In this case, in the image forming apparatus, the printing is stopped when the printing of each copy is completed (copy complete) (S403), and re-RIP using the calibration data at time t2 is performed (S404). Then, re-RIP printing is performed using the calibration data at t2.

  In this case, in the conventional processing, when printing by re-RIP, if the value obtained by subtracting the number of copies already printed (here 2 copies) from the expected number of copies (here 3 copies) is set again, the uncollate setting is set. In the same manner as when Collate is set, pages 1, 2, and 3 are printed, and printing is completed (S405). Originally, the user wants to print 3, 3, and 3 pages at the time of re-RIP, but in the conventional example, the print result is not desired by the user.

  The present invention has been made in view of the circumstances as described above. Collate / Unncollate is determined by determining Collate / Unncollate, which is a printing condition specification when shifting to the image quality adjustment mode, and changing the processing method according to the determination, thereby specifying Collate / Unncollate. An object of the present invention is to provide an image processing apparatus capable of obtaining a desired printed matter according to the above.

  In order to solve the above problem, the first technical means of the present invention analyzes input image data and generates drawing data, and density correction generated by measuring density of image formation. An image forming apparatus comprising: density correction means for correcting density of the drawing data using data; and image forming means for developing the drawing data density-corrected by the density correction means and forming an image on a recording medium. A collate / uncollate setting means for setting whether or not to print a plurality of pages of image data in units of copies, and the density correction means has a predetermined value during image formation by the image forming apparatus. When shifting to the image quality adjustment mode, it is determined whether to interrupt the image formation and perform the density correction again according to the setting state of the Collate / Uncollate setting means. .

  According to a second technical means, in the first technical means, when the setting state of the Collate / Uncollate setting means is Collate when the image forming means shifts to the image quality adjustment mode during image formation, When the unit image formation is completed, the image formation is interrupted, the density correction unit performs the density correction again by the density correction data, and the image formation unit uses the drawing data subjected to the density correction again. Then, the image formation after the interruption is executed up to a predetermined amount.

  According to a third technical means, in the second technical means, in the second technical means, if the setting state of the Collate / Uncollate setting means is Uncollate, the image quality adjustment mode is set during image formation. When the process proceeds to, image formation for each page is executed up to a predetermined amount without interrupting image formation even when the image formation for each page is completed and without performing density correction again by the density correction unit. It is characterized by.

  According to a fourth technical means, in the second technical means, when the setting state of the Collate / Uncollate setting means is Uncollate, when the image forming means shifts to the image quality adjustment mode during image formation, When the unit image formation is completed, the image formation is interrupted, the density correction unit performs the density correction again by the density correction data, and the image formation unit uses the drawing data subjected to the density correction again. Thus, image formation in units of pages after interruption is executed up to a predetermined amount.

  According to the present invention, it is possible to obtain a desired printed matter according to Collate / Unncollate designation by determining Collate / Unncollate which is a printing condition designation at the time of shifting to the image quality adjustment mode and changing the processing method according to the judgment. An image processing apparatus configured to be able to be provided can be provided.

1 is a block diagram illustrating a hardware configuration of an embodiment of an image forming apparatus according to the present invention. FIG. 2 is a diagram illustrating a software configuration of the image forming apparatus illustrated in FIG. 1. It is a figure explaining the process example at the time of Collate setting of the image processing apparatus by this invention. It is a figure explaining the example of a process at the time of Uncollate setting of the image processing apparatus by this invention. It is a figure explaining the other example of a process at the time of Uncollate setting of the image processing apparatus by this invention. It is a figure explaining an example of the execution sequence of each module at the time of Collate setting with the image processing apparatus by this invention. It is a figure which shows an example of the execution sequence of each module at the time of Uncollate setting of the image processing apparatus by this invention. FIG. 10 is a diagram describing another example of the execution sequence of each module when setting Uncollate in the image processing apparatus according to the present invention. FIG. 6 is a flowchart for explaining a processing flow of a print driver unit when Uncollate is set in the image processing apparatus according to the present invention. 12 is a flowchart for explaining another example of the processing flow of the print driver when Uncollate is set in the image processing apparatus according to the present invention. FIG. 6 is a diagram illustrating a relationship between an input density of a toner patch and a measured value. It is a figure explaining the example of a correction process of output density. It is a figure which shows an example of the spiral dither matrix when an input density and an output density are in an ideal state. It is a figure which shows an example of the spiral dither matrix when the input density and the output density are not linear. It is a figure explaining an example of the printing order of the image data according to Collate / Uncollate setting. It is a figure for demonstrating an example of the problem in the conventional re-RIP.

FIG. 1 is a block diagram showing a hardware configuration of an embodiment of an image forming apparatus according to the present invention. The image forming apparatus of this example is configured as a multifunction peripheral (MFP) having a scanner, a copy, a printer function, and the like.
The image forming apparatus records an image formation processing unit (ICU) 1 that renders PDL data transmitted from a host computer such as a PC and generates rendering image data, and rendering image data generated by the image formation processing unit 1 A printer control unit (PCU) 2 that forms (prints) an image on a medium such as paper and a scanner unit (SCN) 3 that reads a document image and outputs the image data are provided. The image data generation means, density correction means, and Collate / Uncollate setting means of the present invention are realized by the ICU 1, and the image forming means of the present invention is realized by the printer control unit 2.

  The ICU 1 is a part that performs rendering based on PDL data received from a host computer or the like and generates image data (rendered image data). The NIC (Network Interface Card) 11 that communicates with the host computer, a CPU 12, a RAM 13, VIDEO I / F 14 and I / F 19 that transmit / receive image data and the like to / from the PCU 2, an operation panel 15 that displays an operation screen and various information, and receives user operations, an image between the ROM 16, the HDD 17, and the scanner unit 3. VIDEO I / F 18 and I / F 20 for transmitting and receiving data and the like are provided.

  The PCU 2 controls the print engine to perform printing. The VIDEO I / F 21 and I / F 24 that transmit and receive image data to and from the ICU 1, the CPU 22, the ROM 23, the RAM 25, and both sides that perform duplex printing. A unit 27, a printing unit 29 for printing (image formation) on recording paper, a paper feeding unit 29 for feeding recording paper to the printing unit 29, and the like, a paper discharge unit 30 for discharging the printed recording paper, A unit I / F 26 is provided as an interface between each of these units and the CPU.

  The SCN 3 is a VIDEO I / F 21 and I / F 24 that transmit / receive image data and the like to / from the ICU 1, a CPU 22, a ROM 23, a RAM 25, a duplex unit 27 that performs duplex printing processing, and a print that performs printing (image formation) on recording paper. A unit 29, a paper feeding unit 28 for feeding recording paper to the printing unit 29, etc., a paper discharge unit 30 for discharging printed recording paper, and an interface between these units and a bus to which the CPU 22 is connected. A unit I / F 26 is provided.

FIG. 2 is a diagram showing a software configuration of the image forming apparatus shown in FIG.
The ICU 1 includes a RIP data input unit 101, a printer application module 100, a print driver unit (for printer application) 110, a printer driver (for copy application) 120, a copy application module 130, a scan application module 140, a process for operating as a printer. A control service unit 150, a print service unit 160, a file manager unit 170, a user interface unit 180, and a scan driver unit 190 are included.

  The printer application module 100 includes an interpreter module 102 for interpreting RIP data, a rendering module 104 for converting the interpreted data into bitmap data, and an optimum dither matrix pattern based on image quality adjustment values obtained from the print engine. It has a dither pattern creation unit 103 for selecting and generating, and a RIP data storage unit 105 for storing and storing RIP data for performing re-RIP.

  The print driver unit (for the printer application) 110 includes a printer job management unit 111. The file manager unit 170 saves and manages the bitmap image for each page generated by the printer application module 100, and as a printer job. The print service unit 160 that is managed and commonly used by other applications is registered as a printer job.

  The copy application module 130 includes a copy parameter setting unit 131 for setting copy parameters, and a scan data receiving unit 132 for receiving scan data. When the image processing apparatus 10 executes a copy function as an MFP, the copy application module 130 receives a copy parameter instructed by the user from the user interface unit 180, and instructs the scan driver unit 190 to perform a scan operation based on the information. To do. The user interface unit 180 includes an operation panel control unit 181 that controls the operation panel and a parameter management / storage unit 182 that manages and stores parameters.

  The scan driver unit 190 includes a scan data receiving unit 191, and obtains scan data by operating the scanner at a specified magnification or scan area in accordance with an instruction from the copy application module 130. Thereafter, the copy application module 130 sets the scanned data as a copy job, and print-registers the copy job in the print service unit 160 via the print driver 120 for the copy application.

  The scan application module 140 includes a scan parameter setting unit 141 that sets scan parameters and a scan data receiving unit 142 that receives scan data. When the image processing apparatus 10 executes a scan function as an MFP, the scan application module 140 receives a scan parameter instructed by the user from the user interface unit 180 and performs a scan operation on the scan driver unit 190 based on the information. Instruct. The scan driver unit 190 operates the scanner with the instructed magnification and scan area to obtain scan data.

  The obtained scan data is stored and managed as image data in the image data storage / management unit 171 of the file manager unit 170. The stored image data is sent as a file from the scan application module 140 to a server (not shown) as a file, used as attachment data in a mail, or directly recorded in a USB storage (not shown).

  The print service unit 160 includes a job management unit 161 that manages jobs, a print control unit 162 that performs print control, and a status management unit 163 that manages the status of the print engine obtained from the PCU. The print driver unit of each application By handling the print job data registered from 110 and 120 as print queue data, the order in which each job is processed is determined and managed.

The print service unit 160 also provides various status information of the print engine obtained from the PCU 2, such as the paper size and remaining amount of paper in each paper feed tray, the status of the paper discharge tray, the print execution status, and the remaining staple staples of the finisher. It has a function of obtaining volume information, punching volume capacity information, printing machine temperature, humidity information, and the like and displaying them on the operation panel through the user interface unit 180.
The print service unit 160 suspends printing through the PCU 2 when the user makes a job cancel processing request from the operation panel during printing and the job currently being printed is the target. . Then, after the printing is stopped, the job is deleted by requesting the print driver units 110 and 120 that manage the job to delete the registered job.

  The process control service unit 150 includes an image quality adjustment unit 151, and is based on humidity / temperature information obtained by the print service unit 160, an elapsed time since the last calibration execution, the number of printed sheets, a used toner amount, and the like. When the condition is satisfied, calibration (also referred to as a process control) is performed by the printing engine, and the printing press itself is adjusted. At the same time, information for density correction is obtained, and processing for preventing deterioration in image quality due to changes in print image quality over time is performed.

  The density correction information obtained by the process control service unit 150 is used as data for generating a dither matrix used by the printer application module 100 during rendering. The density correction information is used as a parameter for image quality adjustment by the print service unit 160 when printing RGB data input by the copy application module 130 or the like.

  The PCU 2 communicates with the process control service unit 150 and performs calibration, a calibration unit 200 that performs calibration, a print data reception unit 210 that receives print data from the print service unit 160, a print unit control unit 220 that controls the print unit, and paper feed A sheet feed unit control unit 230 that controls the unit, a duplex unit control unit 240 that controls the duplex unit, and a sheet discharge unit control unit 250 that controls the sheet discharge unit are provided.

  The SCN 3 communicates with the scan driver unit 190 to control the scan data transmission unit 310 that transmits scan data, the scan calibration unit 320 that performs scan calibration, the scanner unit control unit 330 that controls the scanner unit, and the ADF unit. An ADF unit controller 340 is provided.

FIG. 3 is a diagram for explaining a processing example when Collate is set in the image processing apparatus according to the present invention. Here, a state where re-RIP (reproduction processing of intermediate data) based on density correction data is performed when three copies of original image data of three pages is printed in Collate setting is shown.
First, the image forming apparatus that has received the print data acquires density correction data (calibration data) at time t1, performs density correction processing on the image data to generate intermediate data, rasterizes it, and starts printing ( S101). The printing order is 1, 2, and 3 pages. Here, 3 copies are designated as the number of copies to be printed.

After the first copy is completed, the second copy is printed again in the order of pages 1, 2, and 3. However, when the second copy of the first page is completed, a new image quality adjustment is performed. It is assumed that calibration data is created at time t2 (S102).
In this case, the image forming apparatus stops printing when the unit printing is completed (copies are completed) (S103), performs re-RIP using the calibration data at time t2 (S104), and the rest The number of copies (in this case, 1) is printed. This completes printing (S105). The Collate processing shown here is the same as the conventional processing.

FIG. 4 is a diagram for explaining a processing example when setting Uncollate in the image processing apparatus according to the present invention. Here, a situation is shown in which, when three copies of original image data of three pages are printed in Uncollate setting, re-RIP based on density correction data is not performed.
In the image forming apparatus that has received the print data, calibration data at time t1 is acquired, density correction processing is performed on the image data, intermediate data is generated, rasterized, and printing is started (S111). Since the setting is Uncollate, the printing order is 1, 1, and 1 pages. Three copies are designated as the number of print copies.

  After printing one page, the second page is printed in the order of 2, 2, and 2 pages. When the first page of the second page is printed, a new calibration by image quality adjustment is performed. It is assumed that data was created at time t2 (S112). In this case, since the re-RIP process is not performed in this example, printing is not stopped and all the pages up to the third page are printed and printing is completed (S113). That is, even if new calibration data is created during the printing process of a single print job, re-RIP using the new calibration data is not executed during the printing process of the print job. The new calibration data is reflected in the next print job (New Job).

  By such processing, the re-RIP processing same as Collate setting is not performed at the time of creating new calibration data even when Uncollate setting is made, and a user-desired print result (3 pages from 1 to 3) is obtained. be able to. Also, the new calibration data can be reflected from the next print job, and the printing process can be executed with an appropriate image quality based on the density correction data.

FIG. 5 is a diagram for explaining another example of processing at the time of setting Uncollate of the image processing apparatus according to the present invention. Here, a state is shown in which the re-RIP is set based on the density correction data when three copies of the original image data of three pages are printed in the Uncollate setting.
In the image forming apparatus that has received the print data, calibration data at time t1 is acquired, density correction processing is performed on the image data, intermediate data is generated, rasterized, and printing is started (S121). Since the setting is Uncollate, the printing order is 1, 1, and 1 pages. Three copies are designated as the number of print copies.

  After printing the first page, the second page is printed in the order of 2, 2, and 2. However, when the first page of the second page is finished, a new calibration by image quality adjustment is performed. It is assumed that the action data is created at time t2 (S122). In this case, in order to perform re-RIP, the printing is stopped at the end of printing (copy complete) (S123), and re-RIP is executed using the calibration data at time t2 (S124). Since printing of up to two pages has already been completed, only the third page of the generated page data is registered for printing (S125). Then, three sheets of the third page are printed. This completes printing (S126).

  By such processing, the re-RIP processing same as Collate setting is not performed at the time of creating new calibration data even when Uncollate setting is made, and a user-desired print result (3 pages from 1 to 3) is obtained. be able to. In this case, when new calibration data is created, printing is completed and printing is performed again, and re-RIP is performed. Therefore, the image quality after re-RIP can be improved. In addition, since the re-RIP data is reflected at the timing when the print job is well separated (copy complete), there is no difference in image quality between copies or pages.

FIG. 6 is a diagram illustrating an example of an execution sequence of each module when Collate is set in the image processing apparatus according to the present invention. This sequence corresponds to the processing at the time of Collate setting in FIG.
The process control service unit outputs an image quality adjustment request to the PCU for a predetermined time or every predetermined number of printed sheets, and saves calibration data (density correction data) based on the density information measured according to the image quality adjustment request. A PCU (process control unit) operates hardware of an image forming apparatus, and executes an image forming (printing) operation on a recording medium. A printer application (printer application) issues a print command to the PCU. The print driver unit inputs bitmap image data generated by a printer application (printer emulation) built in the image forming apparatus to a print service. The printer application interprets PDL data input from the PC and generates bitmap data (raster image data).

  Assume that Collate is specified as the printing condition and an instruction to print N copies of image data is issued. When PDL data (RIP data) is input from an external host computer or the like, the printer application starts RIP processing (S1). Here, the input RIP data is analyzed, and intermediate data including a drawing object is generated using density correction data. When the RIP process is completed (S2), the printer application rasterizes the intermediate data and sends it to the print driver unit (S3), and performs job registration in the print service unit (S4). At this time, the number of print copies and Collate / Uncollate conditions specified in the PDL data language are also registered in the print service portion. The print service unit returns to the print driver that the job registration has been completed (S5). The print service unit instructs the PCU to start printing the registered data (S6), and the PCU starts printing (S7).

The process control service unit requests image quality adjustment from the PCU according to the conditions of a fixed time, a fixed number of printed sheets, or both (S8). The PCU temporarily stops printing in response to the image quality adjustment request and sends a print stop event to the print service (S9). Then, the PCU enters the image quality adjustment mode and generates calibration data used by the printer application (S12).
The process control service unit sends a print stop event by image adjustment to the print driver unit before image quality adjustment (S10), and sends an image quality adjustment completion event after image quality adjustment (S13).

  When the print driver unit receives the print stop event sent from the process control service unit, the print driver unit makes a copy complete print stop request to the print service unit (S11). Here, when printing N copies of a plurality of pages, a request is made to stop printing when printing of the Mth (M <N) th copy is completed. This is because printing control becomes complicated if the printing is stopped halfway before the M-th printing is completed and the remaining printing is performed using new RIP data.

The PCU resumes printing in response to the end of image quality adjustment (S15), and at the time of resumption, sends a print resume event to the print service (S16). Then, in response to a copy complete printing stop instruction (S16) from the print service unit, printing is stopped when printing is completed in units of copies, and a copy complete stop completion event is sent to the print driver unit (S17).
When the print driver unit receives the copy complete stop event, it makes a re-RIP request to the printer application (S18). In accordance with the re-RIP request, the printer application executes re-RIP processing using the newly generated calibration data (S19 to S20), and again sends the raster image data of the first page sequentially to the print driver (S21). Then, job registration is performed in the print service (S22). The number of copies to be registered at this time is NM copies excluding M copies that have already been printed.
The print service unit returns to the print driver unit that job registration has been completed (S23). The print service unit instructs the PCU to start printing the registered data (S24), and the PCU starts printing (S25).

  When printing of the remaining number of copies (NM copies) is completed, the PCU sends a print stop event to the print service unit (S26), and the print service unit notifies the print driver unit of job print completion (S27). . Then, the print driver unit issues a RIP data deletion request to the printer application (S28). In response to the request, the printer application deletes the stored RIP data (S29).

  In this manner, the print driver unit determines that the Collate / Uncollate setting of the image processing apparatus is Collate, and outputs a copy complete print stop request to the print service in response to a print stop event input by image quality adjustment. Thus, the printing is stopped at the time when the printing for each copy is completed, and after the re-RIP process is performed, the remaining number of copies is printed. This makes it possible to perform optimum printing according to the Collate / Uncollate setting.

FIG. 7 is a diagram showing an example of an execution sequence of each module at the time of setting Uncollate of the image processing apparatus according to the present invention.
This sequence corresponds to the processing at the time of setting Uncollate in FIG. In this example, it is assumed that Uncollate is designated as the printing condition and an instruction to print N copies of image data is issued. Here, a detailed description of the repetition of the same processing as that in the sequence of FIG. 6 is omitted, and a description will be given mainly of the characteristic features of this example.

  In S31 to S35, the raster image data generated by the printer application is registered in the print service unit via the print driver unit. Here, in S34, the number of copies and the Collate / Uncollate condition specified first in the PDL data language are also registered in the print service. In this example, Uncollate is registered.

After printing is started by the PCU (S37), when the process control service sends a stop event due to image quality adjustment to the PCU (S38), it is determined that the print driver is currently set to Uncollate, Does not make a complete stop request like when Collate is set.
For this reason, the print service ends printing stop by image quality adjustment (S41), continues printing without stopping the copy even when printing is resumed (S44), and completes printing (S45 to S47). Then, the printer application deletes the stored RIP data (S48).

In this way, the print driver determines that the Collate / Uncollate setting of the image processing apparatus is Uncollate, and therefore does not output a copy complete print stop request to the print service even if a print stop event is input due to image quality adjustment. In this way, printing is performed up to the specified number of copies. As a result, even if the Uncollate setting is used, the same re-RIP process as the Collate setting is not performed when creating new calibration data, and a print result desired by the user can be obtained. Also, the new calibration data can be reflected from the next print job, and the printing process can be executed with an appropriate image quality based on the density correction data.
As described above, in the embodiment of the present invention, it is possible to perform optimum printing according to the Collate / Uncollate setting.

FIG. 8 describes another example of the execution sequence of each module at the time of setting Uncollate of the image processing apparatus according to the present invention.
This sequence corresponds to the processing at the time of setting Uncollate in FIG. In this example, it is assumed that Uncollate is designated as the printing condition and an instruction to print N copies of image data is issued. Here, a detailed description of the repetition of the same processing as that in the sequence of FIG. 6 is omitted, and a description will be given mainly of the characteristic features of this example.

  The processing from S51 to S71 is the same as that at the time of Collate setting in FIG. That is, in this example, even when the Uncollate setting is set, when a stop event occurs due to image quality adjustment of the process control service (S60), the print driver unit sends a copy complete stop request to the print service unit (S61). In response to this, the PCU stops printing when printing in units of pages is completed, and sends a copy completion stop event to the print driver unit (S67). In this case, however, the Collate / Uncollate setting is Uncolaate, so the printing order of the PCU is the first page × N, the second page × N,. Here, for example, it is assumed that printing has been completed up to m pages when printing is stopped in response to a request for the completion of copying.

  Thereafter, the printer application performs re-RIP processing (S69). When the re-RIP is completed (S71), the raster image data generated by the printer application is registered in the print service via the print driver unit (S72). At this time, the print driver unit registers the data for the (m + 1) th page and thereafter without registering the data up to m pages for which printing has already been completed in the print service. Also, Uncollate is registered as a Collate / Uncollate condition.

  Then, the PCU prints page m + 1 and subsequent pages with the uncollate setting according to the registered data (S75). When printing is completed, the printer application deletes the stored RIP data (S79).

  In this way, the print driver determines that the Collate / Uncollate setting of the image processing apparatus is Uncollate, and outputs a complete print stop request to the print service when a print stop event is input due to image quality adjustment. Then, the printing is stopped when the printing for each page is completed. Then, the re-RIP process is performed and the remaining pages are printed with the Uncollate setting. Therefore, optimal printing can be performed according to Collate / Uncollate settings without causing a difference in image quality between copies or pages.

FIG. 9 is a flowchart for explaining the flow of processing of the print driver unit when Uncollate is set in the image processing apparatus according to the present invention. When Uncollate is set as shown in FIG. 4, the re-RIP is not performed. The process of a print driver part is shown.
When the print driver unit executes job printing, if job printing has been completed (step S201—Yes), the RIP data is deleted and the process is terminated (step S211). If job printing has not been completed (step S201: No), it is determined whether a stop event due to image quality adjustment from the process control service has been received (step S202). If a stop event due to image quality adjustment has not been received, the process returns to step S201. If a stop event due to image quality adjustment is received, the current setting is confirmed to determine whether the job is a Collate job (step S203).

  If it is not a Collate job, the process returns to step S201. If the job is a Collate job, the print driver unit issues a copy completion request to the print service (step S204). When a copy complete stop event is received from the PCU (step S205), it is determined whether or not job printing is completed (step S206). If completed, the RIP data is deleted and the process is terminated (step S211). If not completed, information on the number of printed copies is acquired (step S207). Then, a re-RIP request is executed (step S208), and if the re-RIP process is completed (step S209-Yes), the remaining number of copies is set in the print service and print registration is performed (step S210).

FIG. 10 is a flowchart for explaining another example of the processing flow of the print driver when Uncollate is set in the image processing apparatus according to the present invention, and re-RIP is performed when Uncollate is set as shown in FIG. The processing of the print driver unit at that time is shown.
When the print driver unit executes job printing, if the job printing is completed (step S301-Yes), the RIP data is deleted and the process is terminated (step S312). If job printing has not been completed (step S301-No), it is determined whether a stop event due to image quality adjustment has been received from the process control service (step S302). If a stop event due to image quality adjustment has not been received, the process returns to step S301. When a stop event due to image quality adjustment is received, the print driver unit issues a copy complete request to the print service unit (step S303).

Then, the print driver unit waits for the reception of the copy complete stop event from the PCU (step S304), and upon receiving the copy complete stop completion event, it determines whether or not job printing has been completed (step S305). If the job printing is completed, the RIP data is deleted and the process is terminated (step S312). If the job printing is not completed, information on the number of printed copies is acquired (step S306). Then, a re-RIP request is executed (step S307), and if the re-RIP process is completed (step S308-Yes), the current setting is confirmed to determine whether the job is a collate job (step S309).
In the case of a Collate job, the printer driver unit sets the remaining number of copies and performs print registration for the print service (step S310). If the job is not a Collate job, only pages larger than the number of printed copies are registered for printing with the print service (S311).

Next, calibration processing executed in the image forming apparatus will be described.
As a main process of the calibration process, when a predetermined condition for executing calibration (hereinafter referred to as a calibration execution condition) is satisfied, the image forming apparatus is placed on the surface of the photosensitive drum or the intermediate transfer member. Test toner images (also referred to as toner patches) having different densities are created. The reflected light from the toner patch generated at each input density is detected using a density sensor such as an optical sensor, and the density of the toner image is measured. By performing this for each color (C, M, Y, K), it is possible to obtain output density data for the input density for each toner color.

  FIG. 11 is a diagram illustrating the relationship between the input density of the toner patch and the measured value. Here, the measured values when the input density is 256 levels from 0 to 255 and the toner patches of each level are measured by the density sensor are shown. FIG. 11A shows an ideal state. When there is no influence of optical and physical dot gain when toner is transferred / fixed on a recording sheet, the output density changes linearly with respect to the input density. To do.

  However, actual measurement results may be as shown in FIGS. 11B to 11D. For example, in FIG. 11B, the actually measured value (output density) increases with respect to the input density, and in FIG. 11C, the output density decreases with respect to the input density. In FIG. 11D, the output density decreases in the range where the input density is low, but the output density increases in the range where the input density is high. In addition, behavior other than these may be exhibited. In such a case, processing for preventing image quality is performed by correcting the output density with respect to the input density.

  FIG. 12 is a diagram for explaining the correction processing in the state of FIG. As shown in FIG. 12, when the input density value is 128, the actually measured density value Oa larger than 128 is obtained. If it is desired to obtain a density of 128 as an actual measurement value, an input value Ia smaller than 128 may be given as the input density. In order to show the basic mechanism related to density correction, here, the input density is an 8-bit gradation with 0-255, and the output gradation of the image forming apparatus is a 1-bit gradation indicated by 0,1. The gradation is expressed by the area gradation method using a spiral dither matrix of 16 dots × 16 dots on one side.

  First, in a state where the ideal input density and output density are linear, a spiral dither matrix corresponding to this is shown in FIG. This dither matrix is a dither pattern in which 0, 1, 2,... Are sequentially set as threshold values in a clockwise direction so as to wind a vortex from the central portion. When the input value 128 is input to this dither pattern, the portion where the threshold value set in each matrix is smaller than 128 is expressed as black (hatched portion), and this is represented by area gradation (128 cells out of 256 cells are black). (Recognized) is represented by a bitmap having a value of output density 128 (FIG. 13B).

When the ideal dither matrix shown in FIG. 13A has an input density-output density relationship as shown in FIG. 12, the output density becomes 128 when the input density is Ia, and the input density At 128, the output density is Oa. For example, when the density is Ia of 115 and Oa of 141, the spiral dither matrix table having the corrected threshold value is as shown in FIG. In FIG. 14A, the cell having a threshold value of 128 is 115 in the ideal state of FIG. 13A. In FIG. 14A, the cell having a threshold value of 141 is the ideal of FIG. It becomes 128 in the state.
By using the dither pattern having this threshold value when the print engine unit has the characteristics as shown in FIG. 12, the output pattern having an input value of 128 is changed to a bitmap output as shown in FIG. Become. By outputting this bitmap with the print engine characteristics shown in FIG. 12, an output density of 128 is obtained. The above is the basic concept of density correction.
Furthermore, not only 1-bit output gradation but also 2-4 bit multi-gradation is supported, and it is used in combination with a dither matrix that outputs multiple stages. In this case, the basic correction principle is the same as that in the case of 1-bit output.

DESCRIPTION OF SYMBOLS 1 ... Image formation process part, 2 ... Printer control part, 3 ... Scanner part, 10 ... Image processing apparatus, 12 ... CPU, 13 ... RAM, 14 ... VIDEO I / F, 15 ... Operation panel, 16 ... ROM, 17 ... HDD, 18 ... VIDEO I / F, 19 ... VIDEO I / F, 20 ... VIDEO I / F, 21 ... VIDEO I / F, 22 ... CPU, 23 ... ROM, 24 ... VIDEO I / F, 25 ... RAM, 26 ... Unit I / F, 27 ... Duplex unit, 28 ... Paper feed unit, 29 ... Printing unit, 30 ... Paper discharge unit, 100 ... Printer application module, 101 ... RIP data input unit, 102 ... Interpreter module, 103 ... Dither pattern Creation unit 104 ... Rendering module 105 ... RIP data storage unit 110, 120 ... Driver unit 111 ... Printer job management unit 120 ... Print driver unit 130 ... Copy application module 131 ... Copy parameter setting unit 132 ... Scan data receiving unit 140 ... Scan application module 141 ... Scan parameter setting unit 142 ... Scan data receiving unit, 150 ... Process control service unit, 151 ... Image quality adjustment unit, 160 ... Print service unit, 161 ... Job management unit, 162 ... Print control unit, 163 ... Status management unit, 170 ... File manager unit, 180 ... User interface unit, 181 ... Operation panel control unit, 182 ... Storage unit, 190 ... Scan driver unit, 191 ... Scan data receiving unit, 200 ... Calibration unit, 210, ... Print data receiving unit, 220 ... Printing unit Control unit, 230 ... feed unit control unit, 240 ... duplex unit control unit, 250 ... discharge unit control unit, 310 ... scan data transmission unit, 320 ... scan calibration unit, 330 ... scanner unit control unit, 340 ... ADF unit controller.

Claims (4)

A drawing data generation unit that analyzes input image data and generates drawing data; a density correction unit that performs density correction of the drawing data using density correction data generated by performing density measurement of image formation; In an image forming apparatus comprising image forming means for developing the drawing data density-corrected by the density correction means and forming an image on a recording medium,
When printing multiple copies of multiple pages of image data, it has Collate / Uncollate setting means for setting whether or not to print in sets,
The density correction unit interrupts image formation and performs the density correction again according to the setting state of the Collate / Uncollate setting unit when the image forming apparatus shifts to a predetermined image quality adjustment mode during image formation. An image forming apparatus that determines whether or not to perform. The image forming apparatus according to claim 1.
When the setting state of the Collate / Uncollate setting unit is Collate, the image forming unit interrupts image formation when the image formation for each unit is completed when the image forming mode is shifted to the image quality adjustment mode during image formation. ,
The density correction unit performs density correction again based on density correction data,
The image forming unit is configured to perform image formation after interruption up to a predetermined amount using the drawing data subjected to the density correction again. The image forming apparatus according to claim 2.
When the Collate / Uncollate setting unit is set to Uncollate, the image forming unit interrupts the image formation even when the image formation for each page is completed when the image forming unit shifts to the image quality adjustment mode during image formation. And an image forming apparatus that performs image formation in units of pages up to a predetermined amount without performing density correction again by the density correction unit. The image forming apparatus according to claim 2.
When the Collate / Uncollate setting unit is set to Uncollate, the image forming unit interrupts image formation when image formation in units of pages is completed when the image quality adjustment mode is entered during image formation. ,
The density correction unit performs density correction again based on density correction data,
The image forming unit is configured to perform image formation in units of pages after interruption up to a predetermined amount by using the drawing data subjected to the density correction again.

Images