JP2009065480A - Image forming apparatus and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus capable of efficiently and surely discriminating misprint even when outputting a lot of pages. <P>SOLUTION: The image forming apparatus includes: a printing section for printing on a recording paper sheet an image based on image data for printing; an output image reading section which reads the printed recording paper sheet to produce output image data; an image comparing section which compares the image data for printing with the output image data to judge presence or absence of a difference between both image data; a display section for displaying images based on the image data for printing and the output image data, respectively, side by side when the presence of the difference is judged; and a paper delivery section for delivering the recorded paper sheet. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and an image forming method, and more particularly to an image forming apparatus capable of determining misprints efficiently and reliably even when a large number of pages are output.

  Commercial printing machines output thousands or tens of thousands of pages at a time, so a sample print system that discharges printed matter to a separate tray at a specified rate is widely used to identify misprints. Has been. However, in the sample printing method, the paper is discharged to another tray at a predetermined rate regardless of whether or not there is a misprint, so that the printing process efficiency deteriorates and the recording paper is wasted. There is.

  In relation to this, the following Patent Document 1 proposes a technique of automatically detecting a misprint by a print success / failure detection unit and discharging the printout to another tray. However, since the technique only detects misprints based on uniform standards, there is a problem in that a detection result desired by the user cannot always be obtained with certainty.

In Patent Document 2 below, an image obtained by scanning the print result is transmitted to the client so that the user can proof (visually confirm) the print result, and further, the image is displayed to the user on the client. Techniques to do this have been proposed. However, in this technique, the user needs to perform proofing for all the pages, and when processing data with a large number of pages, the burden on the user becomes very large, which is inefficient.
JP-A-9-25038 Japanese Patent Laid-Open No. 10-145530

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to form an image that can efficiently and reliably determine misprints even when outputting a large number of pages. An apparatus and an image forming method are provided.

  The above object of the present invention is achieved by the following means.

  (1) A printing unit for printing an image based on printing image data on recording paper, an output image reading unit for reading printed recording paper and generating output image data, the printing image data, An image comparison unit for comparing the output image data to determine whether or not there is a difference, and based on each of the print image data and the output image data when it is determined that there is a difference An image forming apparatus comprising: a display unit for displaying images side by side; and a paper discharge unit for discharging printed recording paper.

  (2) When it is determined that there is a difference, the apparatus further includes a user operation unit that acquires an instruction as to whether or not to normally discharge printed recording paper from a user, and the paper discharge unit A tray and a separate tray, and when the user operation unit obtains an instruction to perform normal paper ejection, the paper ejection tray obtains an instruction to perform normal paper ejection. The image forming apparatus according to (1), wherein the printed recording paper is discharged.

  (3) The user operation unit can further acquire a maintenance instruction for the image forming apparatus from a user, and performs a maintenance designated by the user when the maintenance instruction is acquired by the user operation unit. The image forming apparatus according to (2), further including a maintenance execution unit.

  (4) The image forming apparatus according to (3), wherein the maintenance includes at least one of calibration, gamma adjustment, printing position alignment, and cleaning.

  (5) The image comparison unit performs an exclusive OR operation on each pixel of the print image data and the output image data, and the number of pixels in which the operation result is 1 exceeds a certain reference The image forming apparatus according to any one of (1) to (4), wherein it is determined that there is a difference between the print image data and the output image data.

(6) An image forming method executed in the image forming apparatus, the step of printing an image based on printing image data on recording paper, the step of reading the printed recording paper and generating output image data, A step of comparing the print image data and the output image data to determine whether or not there is a difference between the print image data and the output image data; Tiling images based on, and
And a step of discharging the printed recording paper.

  (7) When it is determined that there is a difference, the method further includes a step of obtaining an instruction as to whether or not to normally discharge the printed recording paper from a user who visually confirms the images displayed side by side; The image forming apparatus according to (6), wherein the printed recording sheet is discharged to a tray different from the normal discharge tray when an instruction not to normally discharge the recording sheet is acquired. Method.

  (8) When it is determined that there is a difference, a step of obtaining an instruction as to whether or not to perform maintenance of the image forming apparatus from a user who visually confirms the images displayed side by side; The image forming method according to (6) or (7), further including a step of performing maintenance instructed by the user when the instruction is acquired.

  (9) The image forming method according to (8), wherein the maintenance includes at least one of calibration, gamma adjustment, printing position alignment, and cleaning.

  (10) The determination of whether or not there is a difference is performed by calculating an exclusive OR of each pixel of the print image data and the output image data, and the number of pixels in which the calculation result is 1 is constant. The image forming method according to any one of (6) to (9), wherein the image forming method is performed by determining that there is a difference when exceeding a reference.

  According to the image forming apparatus and the image forming method of the present invention, the comparison image between the two is displayed only when a certain difference is recognized between the document and the output result thereof, so the user visually confirms the comparison image. Thus, even when a large number of pages are output, misprints can be determined efficiently and reliably. Further, since the user can select a tray as a paper discharge destination based on his / her visual judgment, it is possible to prevent misprints from being mixed into the printed matter. Furthermore, since the user can perform maintenance such as calibration, gamma adjustment, printing position alignment, and cleaning based on his / her own visual judgment, a desired print quality can be easily obtained.

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

  FIG. 1 is a front view showing an appearance of a printer 1 as an image forming apparatus according to an embodiment of the present invention. As shown in FIG. 1, the printer 1 includes an output image reading unit 150 and a display unit 160, which will be described later, and is connected to a finisher 210 having functions such as sorting and stapling when printing a plurality of copies. The finisher 210 includes a separate tray 230 provided separately from the paper discharge tray 220 in addition to the paper discharge tray 220.

  FIG. 2 is a block diagram illustrating a configuration of the printer 1 according to the present embodiment. However, the printer 1 may include components other than the components described later, or may not include some of the components described later.

  As shown in FIG. 2, the printer 1 according to the present embodiment controls each component, and also performs a control unit 10 that performs image processing and the like. A printing unit 140 that prints on the paper), an output image reading unit 150 that is provided on a path from the printing unit 140 to the finisher 210, reads the output print image, and generates output image data; And a display unit 160 that also functions as an operation unit that acquires various instructions from the user according to an instruction, and a communication I / O as described later. The communication network 200 such as a LAN is communicably connected via an F (interface) 130. However, the type and number of devices connected to the communication network 200 are not limited to the above example. Further, the printer 1 may be directly connected (locally connected) to other devices without going through the network 200.

  Next, each component of the printer 1 according to the present embodiment will be described in more detail. First, as shown in FIG. 2, the control unit 10 includes a CPU 100, a memory 110, an HDD (hard disk) 120, and a communication I / F (interface) 130, which are connected via a bus 20.

  The CPU 100 performs control of each component, image processing, various arithmetic processing, and the like according to a program. The memory 110 includes a ROM that stores various programs and parameters in advance, a RAM that temporarily stores programs and data as a work area, and the like. The memory 110 temporarily stores the print image data received from the communication I / F 130. The print image data stored in the memory 110 in this manner is subjected to image processing by the CPU 100 and transferred to the HDD 120 or the printing unit 140 as necessary.

  The HDD 120 stores programs and parameters for the CPU 100 to control each component. Various data stored in the HDD 120 is read by the CPU 100 as necessary and executed or processed on the memory 110.

  The communication I / F 130 is a network interface based on standards such as Ethernet (registered trademark), token ring, and FDDI, and establishes a connection with an external device such as a server or a client via the network 200 and executes transmission / reception of data. . In particular, in this embodiment, the communication I / F 130 receives print image data from an external device.

  The printing unit 140 prints and discharges an image on a recording paper (printing paper) by an electrophotographic method including processes such as charging, exposure, development, transfer, and fixing. However, the printing method of the printing unit 140 in the present embodiment is not limited to this, and an impact method, a thermal transfer method, an ink jet method, and the like can be adopted in addition to the electrophotographic method. In particular, in the present embodiment, the printing unit 140 prints an image based on the printing image data received by the communication I / F 130 according to an instruction from the control unit 10.

  The output image reading unit 150 is provided on the path from the print 140 to the finisher 210 as described above, and reads the recording paper on which the image is printed by the printing unit 140 to generate output image data. More specifically, the printed recording paper conveyed from the printing unit 140 is irradiated with light by a light source such as a fluorescent lamp, the reflected light is photoelectrically converted by a light receiving element such as a CCD or CMOS image sensor, and the electric signal is obtained. Output image data (bitmap data) is generated. Furthermore, the output image reading unit 150 is preferably an EDH scanner capable of reading an image while feeding paper. Here, the EDH scanner is a scanner that reads an image by moving the document relative to the fixed image reading unit rather than moving the image reading unit relative to the fixed document. By adopting the EDH scanner, it is possible to minimize the influence of the scanning operation on the productivity.

  The display unit 160 includes a touch panel type operation panel 500 capable of displaying an image according to an instruction from the control unit 110 and accepting various inputs from the user, and a start key 50 for accepting an instruction such as print execution from the user. (See FIGS. 5 and 6). In the actual embodiment, the display unit 160 can display the print image data received by the communication I / F 130 and the image based on the output image data generated by the output image reading unit 170 side by side. Therefore, the user who has viewed the display unit 160 can determine whether or not the output result from the printing unit 160 is a misprint by visually confirming the difference between the displayed images.

  In addition to the above components, the printer 1 is mounted with components (not shown) for performing maintenance such as calibration, gamma adjustment, and print alignment described later.

  Next, an outline of the operation of the printer 1 in the present embodiment will be described. FIG. 3 is a flowchart showing a procedure of image processing of the image forming apparatus 1 in the present embodiment. 3 is stored as a control program in the HDD 120, and is read out and executed by the control unit 10 at the start of the operation.

  When the printer 1 receives image data for printing from the outside through the communication I / F 130, the following procedure is repeated until output (printing) for all pages is completed (S301).

  First, the printer 1 uses the printing unit 160 to print an image based on the printing image data on recording paper (S302). At this time, it is assumed that the image data for printing is stored in the HDD 120.

  Subsequently, the printer 1 determines whether or not the paper discharge reading mode is set (S303). If the paper discharge reading mode is not set (NO in S303), the image based on the print image data is determined. Is discharged to the paper discharge tray 220 (S309), and the process returns to step S301.

  When the paper discharge reading mode is set (YES in S303), the output image reading unit 170 reads the printed recording paper and generates output image data (S304). This output image data is stored in the HDD 120. Note that, as described above, the output image reading unit 170 is provided in the middle of the paper discharge path to the finisher 210, but both sides above and below the path so that both sides of the transported recording paper can be read. May be arranged. In addition, a configuration in which both sides of the printed paper are scanned using the duplex printing mechanism of the printer 1 is also possible.

  Subsequently, the printer 1 reads out the printing image data and the output image data generated in S304 from the HDD 120, and then compares both image data by the control unit 10 and analyzes whether or not there is a difference between them (see FIG. S305). At this time, the control unit 10 performs an exclusive OR (XOR) operation on each pixel of both image data, and calculates the number of pixels whose operation result is 1 (that is, the input values of XOR are different from each other). Counting is performed, and it is determined whether there is a difference between the two image data depending on whether the count number is larger than a predetermined determination criterion.

  As a result, when it is determined that there is no difference between the two image data (NO in S306), the printed recording paper is discharged to the paper discharge tray 220 (S309), and the process returns to step S301.

  If it is determined that there is a difference between the two image data (YES in S306), an image based on the print image data and the output image data is displayed side by side on the operation panel 500 of the display unit 160, and then the printing process is performed. Pause. At this time, it is preferable that a warning message prompting the user to confirm the displayed image is also displayed. FIG. 5 is a diagram illustrating a display example of the operation panel 500. As shown in FIG. 5, the job owner window 520 on the left side of the operation panel 500 displays the owner name (Job Owner) of the job being processed and the processing status (Status) of each job. As described above, when it is determined that there is a difference between the printing image data and the output image data, images based on both image data are displayed side by side on the right side of the operation panel 500. It can be seen from the number of pages above both images that the output image being displayed is the 340th image out of 5300 images. Further, a warning message “Image error has occurred” is displayed in the message display section 510 below both images.

  Subsequently, the printer 1 acquires a predetermined instruction from the user who visually confirms the image displayed in the operation panel 500, and performs processing based on the instruction (S308). Here, the operation panel 500 also obtains instructions from the user. Specifically, as shown in FIG. 5, buttons for “maintenance” and “discharge to another tray” are displayed on the right side of the warning message display unit 510, and the user can select “maintenance” and “ By pressing one of the “discharge to tray” buttons or the start key 50, a process to be executed thereafter can be selected based on the result of its own visual confirmation. This point will be further described later. Here, the process (S308) that the printer 1 should perform according to the user's instruction will be described. FIG. 4 is a flowchart showing the procedure of the processing. As shown in FIG. 4, the printer 1 repeats the following process until an instruction to continue printing is obtained from the user (that is, until the start key 50 is pressed by the user) (S 401).

  First, the printer 1 acquires operation unit information based on a user selection result on the operation panel 500 as shown in FIG. 5 (S402). When maintenance is selected by the user (S403), the printer 1 shifts to the maintenance mode (S404).

  When the printer 1 shifts to the maintenance mode in this way, the message display unit 510 in the operation panel 500 is switched as shown in FIG. That is, the message display window 510 in FIG. 5 disappears, and an operation window 610 including buttons for “calibration”, “gamma adjustment”, “print alignment”, and “cleaning” is newly displayed. When “calibration” is selected in the operation window 610, the printer 1 automatically executes calibration. When “gamma adjustment” is selected, the job owner window 520 in FIG. 5 disappears, and a gamma adjustment window 620 as shown in FIG. 6 is newly displayed. Then, the printer 1 performs gamma adjustment according to the operation of the slider 630 by the user. When “print alignment” is selected, print alignment sliders 640 and 650 are newly displayed on the left and below the output image displayed on the operation panel 500. Then, the printer 1 adjusts the printing position according to the operation of the sliders 640 and 650 by the user. When “cleaning” is selected, the printer 1 automatically executes the cleaning of the printing unit 140. In the example of FIG. 6, since the upper left portion of the output image is dirty, the user preferably selects “cleaning”.

  When the user selects “discharge to another tray” (S405), the printer 1 sets the discharge destination of the printed recording paper to another tray (S406).

  If the user presses the start key 50 and print continuation is selected (S407), the printer 1 ends the series of processing and returns to the flowchart of FIG.

  Subsequently, the printer 1 discharges the printed recording paper to the paper discharge tray or another tray (S309), and returns to step S301 again. Then, when the discharge of all pages of the received print job is completed, a series of processing is ended.

  As described above, according to the printer 1 of the present embodiment, only when a certain difference is recognized between the document (printing image data) and the output result (output image data), the comparison image between the two is displayed. Therefore, by visually checking the comparative image, the user can efficiently and reliably determine misprinting even if the number of printed sheets is several thousand to several tens of thousands. In addition, since the user can select a discharge destination tray based on his / her own visual judgment, it is possible to prevent misprints from being mixed into the printed matter. Furthermore, since the user can perform maintenance such as calibration, gamma adjustment, printing position alignment, and cleaning based on his / her own visual judgment, a desired print quality can be easily obtained.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims. For example, in the above embodiment, the image forming apparatus of the present invention has been described as a printer, but the present invention is not limited to this. As another aspect of the image forming apparatus of the present invention, a single unit such as a scanner, a printer, a digital copying machine, a facsimile machine, an e-mail printer, or an MFP (Multi Function Peripheral Multifunctional Peripheral Device) having two or more of these functions Etc. When the image forming apparatus has a scanner function, the above processing can be executed using image data obtained by scanning a document instead of image data for printing received from the outside.

  Also, each means and image forming method constituting the image forming apparatus according to the present invention can be realized by a dedicated hardware circuit or a programmed image forming apparatus. When the present invention is realized by a programmed image forming apparatus, a program for operating the image forming apparatus can be provided by a computer-readable recording medium such as a floppy (registered trademark) disk or a CD-ROM. In this case, the program recorded on the computer-readable recording medium is usually transferred and stored in a ROM, a hard disk or the like. Further, this program may be provided as, for example, a single application software, or may be incorporated in the software of the apparatus as one function of the image forming apparatus.

1 is a front view showing an appearance of an image forming apparatus according to an embodiment of the present invention. 1 is a block diagram illustrating a configuration of an image forming apparatus according to an embodiment. It is a flowchart which shows the procedure of the process of the image processing apparatus in this embodiment. It is a flowchart which shows the procedure of the process of the image processing apparatus in this embodiment. It is the schematic which shows the example of a display by an operation panel. It is the schematic which shows the example of a display by an operation panel.

Explanation of symbols

1 printer,
10 control unit,
130 Communication I / F,
140 printing section,
150 output image reading unit,
160 display unit,
200 communication network,
210 Finisher,
220 paper output tray,
230 Separate tray,
500 Operation panel.

Claims (10)

A printing unit for printing an image based on image data for printing on a recording paper;
An output image reader for reading printed recording paper and generating output image data;
An image comparison unit for comparing the print image data and the output image data to determine whether there is a difference between the two,
A display unit for displaying images based on the print image data and the output image data side by side when it is determined that there is a difference;
An image forming apparatus comprising: a paper discharge unit for discharging printed recording paper. A user operation unit for obtaining an instruction as to whether or not to normally discharge the printed recording paper from the user when it is determined that there is a difference;
The paper discharge unit includes a normal paper discharge tray and another tray, and when an instruction to perform normal paper discharge is acquired by the user operation unit, an instruction to not normally discharge the paper is provided to the paper discharge tray. 2. The image forming apparatus according to claim 1, wherein when the image is acquired, the printed recording paper is discharged to the separate tray. The user operation unit can further obtain an instruction for maintenance of the image forming apparatus from a user,
The image forming apparatus according to claim 2, further comprising a maintenance execution unit that executes maintenance designated by a user when a maintenance instruction is acquired by the user operation unit.   The image forming apparatus according to claim 3, wherein the maintenance includes at least one of calibration, gamma adjustment, printing position alignment, and cleaning.   The image comparison unit performs an exclusive OR operation for each pixel of the print image data and the output image data, and when the number of pixels for which the operation result is 1 exceeds a certain reference, 5. The image forming apparatus according to claim 1, wherein it is determined that there is a difference between the print image data and the output image data. An image forming method executed in an image forming apparatus,
Printing an image based on image data for printing on a recording paper;
Reading printed recording paper and generating output image data;
Comparing the image data for printing and the output image data to determine whether there is a difference between the two,
When it is determined that there is the difference, displaying the images based on each of the print image data and the output image data side by side;
And a step of discharging the printed recording paper. When it is determined that there is a difference, the method further includes a step of obtaining an instruction as to whether or not to normally discharge the printed recording paper from a user who visually confirms the images displayed side by side;
The image forming apparatus according to claim 6, wherein the printed recording sheet is discharged to a tray different from a normal discharge tray when an instruction not to normally discharge the recording sheet is acquired. Method. Obtaining an instruction as to whether or not to perform maintenance of the image forming apparatus from a user who visually confirms the images displayed side by side when it is determined that there is the difference;
The image forming method according to claim 6, further comprising a step of executing maintenance instructed by a user when an instruction to perform maintenance is acquired.   The image forming method according to claim 8, wherein the maintenance includes at least one of calibration, gamma adjustment, printing position alignment, and cleaning.   The determination as to whether or not there is a difference is performed by calculating an exclusive OR of each pixel of the printing image data and the output image data, and the number of pixels in which the calculation result is 1 exceeds a certain standard. 10. The image forming method according to claim 6, wherein the image forming method is performed by determining that there is a difference between the image forming method and the image forming method.

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