Image forming apparatus, method for controlling image forming apparatus, and program

Abstract

To efficiently detect a white blank portion in image formation to facilitate performing a method for coping with the white blank portion.SOLUTION: An image forming apparatus 103 comprises: a control unit 10 that controls the operation of units; and an image forming unit (printing unit 72) that forms an image on a print medium. The control unit 10 has an image data generation unit 31 that generates image data on the basis of print job data, and a white blank detection unit 36 that detects a white blank portion in an edge portion of the image data on the basis of size data of the image data.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus, a control method for an image forming apparatus, and a program. [Background technology]

[0002] Manufacturers of image forming devices have attempted to prevent blank areas from appearing in printed images. For example, Patent Document 1 discloses an invention for preventing blank areas from appearing in edges of characters and lines. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-205967 A Summary of the Invention [Problem to be solved by the invention]

[0004] In printing, depending on the data, an error in the floating point calculation of the interpreter may occur, causing blank pages in the media image formed on the print medium. Here, the interpreter is software that converts a computer program written in a high-level programming language (high-level language) that is easy for humans to understand into a format that the computer can interpret and execute, while simultaneously executing the program little by little. In order to eliminate blank pages, it is necessary to select and determine a method of dealing with each blank phenomenon for the image data. Note that, as a method of dealing with blank parts, for example, a warning may be notified to the user, the blank parts may be filled in, or data processing may be performed to suppress the occurrence of blank parts.

[0005] The present invention has been made in consideration of the problems associated with the above-mentioned conventional technology, and an object of the present invention is to provide an image forming apparatus, a control method for an image forming apparatus, and a program that make it easier to deal with whiteout areas. [Means for solving the problem]

[0006] The above-mentioned object of the present invention can be achieved by the following means.

[0007] (1) An image forming apparatus comprising: a control unit that controls the operation of each unit; and an image forming unit that forms an image on a printing medium, wherein the control unit has an image data generation unit that generates image data based on print job data; and a whiteout detection unit that detects whiteout portions at the edges of the image data based on size data of the image data.

[0008] (2) An image forming apparatus as described in (1) above, characterized in that it has a database for storing various types of image data, in which at least size data of image data included in the print job data is registered, and the whiteout detection unit compares the size data of the generated image data generated by the image data generation unit with size data of a corresponding page of registered print job data registered in the database and size data of an object if the corresponding page contains an object, to detect whiteout portions at the edges of the generated image data.

[0009] (3) The image forming apparatus according to (1) above, characterized in that the control unit further has a data processing unit that deletes any data portion after the decimal point from the size data of the image data included in the print job data.

[0010] (4) The image forming apparatus described in (3) above, characterized in that the data processing unit deletes any data portion below the decimal point from the size data of the image data so as to suppress the occurrence of errors in floating-point calculations performed when the image data generation unit generates the image data.

[0011] (5) The image forming apparatus according to (1) above, wherein the control unit further has an image expansion unit that expands an adjacent portion adjacent to the whiteout portion to fill in the whiteout portion.

[0012] (6) The image forming apparatus according to (1) above, wherein the control unit further includes a warning notification unit that notifies a user of a warning when the blank portion is detected.

[0013] (7) The image forming device described in (6) above, characterized in that when the warning notification unit detects the whiteout portion, it causes the display unit to display a screen including a selection button for executing printing, a selection button for performing a process of expanding an adjacent portion adjacent to the whiteout portion to fill in the whiteout portion, and a selection button for canceling printing.

[0014] (8) The image forming apparatus according to (1) above, characterized in that the control unit further has a selection processing unit that accepts a method of dealing with the white-out portion selected by a user when the white-out portion is detected.

[0015] (9) An image forming device as described in (1) above, characterized in that roll paper can be used as the printing medium, and the image forming device is provided with a roll paper feed section that feeds the roll paper downstream, and a roll paper receiving section that receives the roll paper fed by the roll paper feed section.

[0016] (10) A control method for an image forming apparatus, comprising the steps of: acquiring print job data; registering size data of image data included in the print job data in a database; generating image data based on the print job data; and comparing the size data of the generated generated image data with size data of a corresponding page of registered print job data registered in the database and size data of an object if the corresponding page includes an object, to detect whiteout portions at the edges of the generated image data.

[0017] (11) The control method for an image forming apparatus according to (10) above, characterized in that in the process of registering the size data in the database, a process is performed to delete any data portion of the size data below the decimal point.

[0018] (12) The control method for an image forming apparatus according to (10) above, further comprising the step of notifying a user of a warning when a whiteout portion is detected at an edge portion of the generated image data.

[0019] (13) The control method for an image forming apparatus according to (10) above, further comprising a step of, when a whiteout portion is detected in an edge portion of the generated image data, allowing a user to select a method for dealing with the whiteout portion.

[0020] (14) The control method for an image forming apparatus according to (10) above, further comprising a step of, when a whiteout portion is detected at an edge portion of the generated image data, expanding an adjacent portion adjacent to the whiteout portion to fill in the whiteout portion.

[0021] (15) A program for causing a control unit of either an image forming device or an information processing device to execute the following steps: acquiring print job data; registering size data of image data included in the print job data in a database; generating image data based on the print job data; and comparing the size data of the generated generated image data with size data of a corresponding page of registered print job data registered in the database and size data of an object if the corresponding page includes an object, to detect white areas at the edges of the generated image data. Effect of the Invention

[0022] According to the present invention, it is possible to easily take measures against blank areas. [Brief description of the drawings]

[0023] [Figure 1] 1 is a diagram illustrating the overall configuration of an image forming system including an image forming apparatus according to an embodiment. [Diagram 2] FIG. 2 is an internal block diagram of a user terminal and an image forming apparatus according to an embodiment. [Diagram 3] 4 is a flowchart showing an operation of the image forming apparatus according to the embodiment. [Figure 4] 13 is an explanatory diagram showing an example of a warning notification screen displayed on the display unit when a blank portion is detected; FIG. [Diagram 5] FIG. 11 is an explanatory diagram of the operation of an image extension unit. [Figure 6A] FIG. 1 is an explanatory diagram (1) of the operation of the data processing unit. [Figure 6B] FIG. 2 is an explanatory diagram (2) of the operation of the data processing unit. [Figure 7] FIG. 4 is an explanatory diagram of a drawing command. [Figure 8] FIG. 11 is an explanatory diagram of size data registered in a database. [Figure 9] 10 is a flowchart showing an operation of a blank area detection unit. [Figure 10] FIG. [Figure 11] An explanatory diagram of the comparison of size data of generated image data generated from print job data with size data of the corresponding page of registered print job data registered in a database and size data of objects included in the corresponding page. [Figure 12] FIG. 13 is an explanatory diagram of a matching method and conditions. [Figure 13A] 11 is a diagram illustrating the operation of an image extension unit. FIG. [Figure 13B] 11 is a diagram illustrating the operation of an image extension unit. FIG. [Figure 14A] 10A and 10B are explanatory diagrams of streaks formed on the roll paper. [Figure 14B] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Note that each drawing is merely a schematic illustration to allow a sufficient understanding of the present invention. Therefore, the present invention is not limited to the illustrated examples. In addition, in each drawing, common or similar components are given the same reference numerals, and duplicated explanations thereof will be omitted.

[0025] <Configuration of an image forming system including an image forming apparatus> Hereinafter, a configuration of an image forming system 100 including an image forming apparatus 103 according to an embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a diagram showing the overall configuration of an image forming system 100 including an image forming apparatus 103 according to the present embodiment.

[0026] 1, the image forming system 100 includes a data creation device 101, a user terminal 102, and an image forming device 103. The data creation device 101 is a device that creates print job data D11 (PDL data). The user terminal 102 is a device that transmits the print job data D11 created by the data creation device 101 to the image forming device 103. The image forming device 103 is a device that forms an image on a print medium 106.

[0027] In this embodiment, the image forming device 103 can use roll paper as the print medium 106, and will be described as including a print medium feeding unit 104 and a print medium receiving unit 105. The print medium feeding unit 104 is a roll paper feeding unit that feeds the roll paper downstream. The print medium receiving unit 105 is a roll paper receiving unit that receives the roll paper fed by the print medium feeding unit 104.

[0028] The image forming apparatus 103 has a control unit 10 that controls the operation of each unit, and a storage unit 20 that stores various programs and data. A database DB in which various data is registered is constructed in the storage unit 20. The image forming apparatus 103 also has an operation panel 60 that is operated by a user. The operation panel 60 is provided with a display unit 61, operation keys 62 that are an input unit, and a notification unit speaker 63.

[0029] <Internal configuration of user terminal and image forming apparatus according to embodiment> The internal configurations of the user terminal 102 and the image forming apparatus 103 will be described below with reference to Fig. 2. Fig. 2 is an internal block diagram of the user terminal 102 and the image forming apparatus 103.

[0030] As shown in FIG. 2, the user terminal 102 has a printer driver 102a for causing the image forming device 103 to form (print) an image, a print job data generation unit 102b for generating print job data D10, and a network interface 102c for communicating with other devices.

[0031] The image forming device 103 also has the control unit 10, the memory unit 20, the operation panel 60, a network interface 71 for communicating with other devices, and a printing unit 72 (image forming unit) for forming an image on a printing medium 106.

[0032] The control unit 10 has an image data generation unit 31, a data processing unit 34, a blank area detection unit 36, a warning notification unit 37, an image extension unit 38, and a selection processing unit 39. These components are constructed by installing a control program Pr from a storage medium 111 into the image forming apparatus 103. The control program Pr can be installed not only into the image forming apparatus 103, but also into an information processing device (not shown) constituted by a personal computer, a tablet terminal, or the like.

[0033] The image data generating unit 31 is a component that generates image data D12 (FIG. 5) that is raster data of a page image based on print job data D11 that is PDL data.

[0034] The data processing unit 34 is a component that performs various processes on any data. For example, the data processing unit 34 can delete any data portion below the decimal point from the size data of the image data D12 included in the print job data D11. In this embodiment, the data processing unit 34 will be described as having a data inspection unit 32 that inspects any data, and a data registration unit 33 that registers the data in the database DB.

[0035] The blank area detection unit 36 ​​is a component that detects blank areas in image data D12, which is raster data of a page image. In this embodiment, the blank area detection unit 36 ​​is described as detecting blank areas in an edge portion R12 (FIG. 5) of the image data D12 based on size data of the image data D12.

[0036] The warning notification unit 37 is a component that notifies the user of a warning. In this embodiment, the warning notification unit 37 is described as notifying the user of a warning by, for example, displaying a warning notification screen I11 shown in FIG.

[0037] The image expansion unit 38 is a component that expands the adjacent portion adjacent to the blank portion to fill in the blank portion.

[0038] The selection processing unit 39 is a component that, when a blank portion is detected, accepts a countermeasure for the blank portion selected by the user. In this embodiment, when a blank portion is detected, the warning notification unit 37 displays, for example, a warning notification screen I11 shown in FIG. 4 on the display unit 61. The user selects one countermeasure from among the multiple countermeasures displayed on the warning notification screen I11. The selection processing unit 39 accepts the countermeasure selected by the user and executes the processing of the selected countermeasure (however, it may be caused to be executed by another component).

[0039] A control program Pr is stored in the storage unit 20. The storage unit 20 also stores a database in which various data are registered.

[0040] <Operation of image forming device> In this embodiment, the image forming apparatus 103 will be described as operating as follows. The image forming apparatus 103 can specify a size data portion in which an error is likely to occur in a floating point calculation performed when generating image data (raster data) from print job data D11 (PDL data) by the control program Pr or a user. A size data portion in which an error is likely to occur is, for example, a data portion with any decimal point (particularly, a data portion with three decimal places or less). When a size data portion in which an error is likely to occur is specified, the image forming apparatus 103 registers the size data portion in which an error is likely to occur in the database DB.

[0041] (1) In the data creation device 101 (or the user terminal 102), print job data D11 in a PDL (Page Description Language) format is generated by an application, a printer driver, etc. A user operates the user terminal 102 to transmit the print job data D11 (PDL data) to the image forming device 103, and the image forming device 103 receives the print job data D11.

[0042] (2) The image forming apparatus 103 stores the received print job data D11 (PDL data) in the storage unit 20. Next, the image forming apparatus 103 detects the page size of the page image data included in the print job data D11 (PDL data) from the print job data D11 by the data inspection unit 32. Then, the image forming apparatus 103 registers the detected page size in the database DB by the data registration unit 33. At this time, if a data portion with three decimal places or less is registered in the database DB as a size data portion that is prone to errors in floating point calculations, for example, the data inspection unit 32 deletes the data portion with three decimal places or less from the page size (page size data). This allows the image forming apparatus 103 to suppress the occurrence of errors in floating point calculations.

[0043] (3) The image forming apparatus 103 also detects the position and size of each object in the print job data D11 (PDL data) using the data inspection unit 32. Then, the image forming apparatus 103 causes the data registration unit 33 to register the position and size of each object for each page in the database DB.

[0044] (4) When the image forming device 103 finishes receiving the print job data D11 (PDL data), the image data generating unit 31 starts rasterization (RIP) processing of the print job data D11. Then, the image forming device 103 checks, by the blank area detecting unit 36, the rasterized valid image of the corresponding page against the positions and sizes of the objects registered in the database DB to determine whether or not blank areas have occurred.

[0045] (5) If blank areas have occurred, the image forming apparatus 103 notifies the user that blank areas have been detected by displaying, for example, a warning notification screen I11 (FIG. 4) on the display unit 61. Here, the warning notification screen I11 (FIG. 4) is described as having selectable buttons displayed thereon: "Continue printing", "Fill up", and "Abort printing".

[0046] (6) When the user selects the "Continue printing" button on the warning notification screen I11 (FIG. 4), the image forming device 103 continues printing (image formation) as is. When the user selects the "Perform filling" button on the warning notification screen I11 (FIG. 4), the image forming device 103 fills in the blank portion by expanding the adjacent portion adjacent to the blank portion using the image expansion unit 38. When the user selects the "Cancel printing" button on the warning notification screen I11 (FIG. 4), the image forming device 103 cancels printing (image formation).

[0047] Hereinafter, the operation of the image forming apparatus 103 will be described in detail with reference to Fig. 3. Fig. 3 is a flowchart showing the operation of the image forming apparatus 103. The operation of the image forming apparatus 103 shown in Fig. 3 is mainly performed by the control unit 10.

[0048] 3, first, the image forming apparatus 103 receives print job data D11 (PDL data) via the network interface 71 (step S105), and registers the print job data D11 (PDL data) in the database DB via the data registration unit 33. Hereinafter, the print job data registered in the database DB will be referred to as "registered print job data."

[0049] Next, the image forming apparatus 103 determines whether the page size and / or the position and size of an object of the image data included in the print job data D11 (PDL data) has been detected by the data inspection unit 32 (step S110).

[0050] If it is determined in step S110 that the page size and / or the position and size of the object have been detected (if "Yes"), the image forming device 103 registers the page size and / or the position and size of the object in the database DB via the data registration unit 33 (step S115).

[0051] If it is determined in step S110 that the page size and / or the object position and size have not been detected ("No"), or after step S115, the image forming device 103 determines whether the data processing unit 34 has completed receiving the print job data D11 (PDL data) (step S120).

[0052] If it is determined in step S120 that reception of the print job data D11 (PDL data) has not been completed ("No"), the process returns to step S110.

[0053] On the other hand, if it is determined in step S120 that reception of the print job data D11 (PDL data) has been completed (if "Yes"), the image forming device 103 starts rasterization (RIP) processing of the print job data D11 (PDL data) by the image data generation unit 31 (step S125). Then, the image forming device 103 generates rasterized page image data (step S130). Hereinafter, the generated page image data will be referred to as "generated image data."

[0054] After step S130, the image forming device 103 scans the generated image data using the white space detection unit 36, and performs a process of detecting white space in the page image data by comparing the size data of the generated image data with the size data of the corresponding page in the registered print job data and the object if the corresponding page contains an object (step S135).

[0055] After step S135, the image forming apparatus 103 determines whether or not a blank portion has been detected by the blank portion detection unit 36 ​​(step S140).

[0056] If it is determined in step S140 that a blank portion has been detected (if "Yes"), the image forming apparatus 103 notifies the user of the detection of the blank portion through the warning notification unit 37 (step S145).

[0057] In this embodiment, in step S145, the warning notification unit 37 displays the warning notification screen I11 shown in FIG. 4 on the display unit 61 of the operation panel 60. FIG. 4 is an explanatory diagram showing an example of the warning notification screen I11 displayed on the display unit 61 when a blank portion is detected. In the example shown in FIG. 4, the warning notification screen I11 has a warning message saying "Blank portion detected", a "Execute printing" button, a "Fill up" button, and a "Cancel printing" button. The "Execute printing" button is a selection button for executing printing. The "Fill up" button is a selection button for executing a process of expanding an adjacent portion adjacent to the blank portion to fill up the blank portion. The "Cancel printing" button is a selection button for canceling printing.

[0058] After step S145, the image forming apparatus 103 causes the selection processing unit 39 to determine what method the user has selected as a method for dealing with the blank portion (step S150).

[0059] If it is determined in step S150 that continuation of printing has been selected (i.e., the "Execute Print" button has been pressed on the warning notification screen I11 shown in FIG. 4), the image forming apparatus 103 accepts continuation of printing via the selection processing unit 39. In this case, the image forming apparatus 103 continues printing as is.

[0060] If it is determined in step S150 that printing cancellation has been selected (i.e., the "Print Cancellation" button has been pressed on the warning notification screen I11 shown in FIG. 4), the image forming apparatus 103 accepts printing cancellation via the selection processing unit 39. In this case, the image forming apparatus 103 cancels printing. This ends the series of routine processes shown in FIG. 3.

[0061] If it is determined in step S150 that the execution of the filling process has been selected (i.e., the "Perform filling" button has been pressed on the warning notification screen I11 shown in FIG. 4), the image forming apparatus 103 accepts the execution of the filling process via the selection processing unit 39. In this case, the image forming apparatus 103 executes the filling process via the image expansion unit 38 (step S155).

[0062] If it is determined in step S150 that continuing printing has been selected, or after step S155, the image forming device 103 determines whether the data processing unit 34 has completed the process of detecting whiteout areas for all pages (step S160).

[0063] If it is determined in step S160 that the process of detecting blank areas has been completed for all pages (if "Yes"), the process of the series of routines shown in Fig. 3 ends. On the other hand, if it is determined in step S160 that the process of detecting blank areas has not been completed for all pages (if "No"), the process returns to step S130.

[0064] <Image extension section operation> The image forming apparatus 103 generates image data D12 (page image) which is raster data based on print job data D11 which is PDL data using the image data generating unit 31. At this time, due to an error in floating point calculation, a blank portion R13 may occur at the edge portion R12 of the print area R11 of the image data D12. When a blank portion R13 occurs, the image forming apparatus 103 can fill in the blank portion R13 by expanding an adjacent portion adjacent to the blank portion R13 using the image expanding unit 38.

[0065] The operation of the image extension unit 38 will be described below with reference to Fig. 5. Fig. 5 is an explanatory diagram of the operation of the image extension unit 38. The left diagram of Fig. 5 shows a main part of the image data D12 generated by the image data generation unit 31. The center diagram of Fig. 5 shows an enlarged view of the edge portion R12 of the print area R11 of the image data D12. The right diagram of Fig. 5 shows the state in which the whiteout portion R13 has been filled in by the image extension unit 38.

[0066] <Operation of the data processing unit (data inspection unit and data registration unit)> (About page size) In the image forming apparatus 103, in order to suppress occurrence of errors in floating point calculations, a size data portion (e.g., a data portion having three decimal places or less) which is likely to cause errors in the floating point calculation may be registered in the database DB. In this case, the image forming apparatus 103 can delete the size data portion (e.g., a data portion having three decimal places or less) which is likely to cause errors by the data processing unit 34. Note that the accuracy of a general interpreter is guaranteed for calculations up to two decimal places.

[0067] Hereinafter, the operation of the data processing unit 34 (the data inspection unit 32 and the data registration unit 33) will be described with reference to Figs. 6A and 6B. Figs. 6A and 6B are explanatory diagrams of the operation of the data processing unit 34, respectively. Figs. 6A and 6B are an example of a page size designation in the print job data D11 (PDL data). In the example shown in Figs. 6A and 6B, the unit is points. When image data (raster data) is generated based on the print job data D11 (PDL data), the page size is converted from points to dots. At that time, the page size is prone to errors in floating point calculations. This may result in blank areas R13 occurring at the edge portions R12 of the print area R11 of the image data D12.

[0068] In the example shown in FIG. 6A, the size data D30 before deletion of the print job data D11 includes, for example, a data portion with three decimal places or less as a size data portion (deletion portion data D31) in which an error is likely to occur. When the size data portion (for example, a data portion with three decimal places or less) in which an error is likely to occur is registered in the database DB, the data inspection unit 32 of the data processing unit 34 deletes the deletion portion data D31 from the size data D30 before deletion. As a result, as shown in FIG. 6B, the data inspection unit 32 of the data processing unit 34 generates size data in which only the size data D32 after deletion remains. The data registration unit 33 of the data processing unit 34 registers the size data in which only the size data D32 after deletion remains in the database DB. That is, the image forming device 103 resets the page size shown in FIG. 6A detected from the print job data D11 to the page size shown in FIG. 6B and registers it in the database DB. As a result, the image forming device 103 can suppress the occurrence of errors in floating point calculation.

[0069] (About objects) The data inspection unit 32 of the data processing unit 34 registers the drawing commands of each corresponding interpreter in advance and detects the commands from within the print job data D11 (PDL data). FIG. 7 is an explanatory diagram showing an example of the drawing command C11. In the example shown in FIG. 7, the drawing command C11 specifies the drawing of an object, and has a configuration including a position coordinate C11a, a fill area C11b, and a fill command C11c. In the example shown in FIG. 7, the drawing command C11 sets a square object of 200 points vertically and 200 points horizontally as a fill area C11b, and fills the fill area C11b with an arbitrary color (for example, blue). The data inspection unit 32 of the data processing unit 34 detects a fill command C11c called "fill" of the drawing command C11 from within the print job data D11 (PDL data). Then, the data inspection unit 32 of the data processing unit 34 detects the position and size of the object that is the target of the fill command C11c from within the print job data D11 (PDL data). After that, as shown in Fig. 8, the data registration unit 33 of the data processing unit 34 registers the position and size of each object for each page in the database DB.

[0070] Fig. 8 is an explanatory diagram of size data D20 registered in database DB. In the example shown in Fig. 8, size data D20 includes page size data D21 and object size data D22. In the example shown in Fig. 8, for example, data "612.48 792.52" is registered as page size data D21 for a page with page number "1". Also, for example, position data "400,500" and size data "200,200" are registered as object size data D22 for the first object included in the page with page number "1".

[0071] <Operation of the whiteout detection unit> The blank area detection unit 36 ​​detects the presence or absence of a blank area R13 in the edge portion R12 of the print area R11 of the image data D12 (raster data) generated by the image data generation unit 31. The operation of the blank area detection unit 36 ​​will be described below with reference to Fig. 9. Fig. 9 is a flowchart showing the operation of the blank area detection unit 36.

[0072] 9, the blank area detection unit 36 ​​scans each line of the image data D12 of the page image rasterized by the image data generation unit 31 from the upper line to the lower line, from the left dot to the right dot of each line (step S205). Hereinafter, the image data D12 of the page image rasterized by the image data generation unit 31 will be referred to as "generated image data D40 (FIG. 10)."

[0073] Fig. 10 is an explanatory diagram of image scanning. In the example shown in Fig. 10, the blank detection unit 36 ​​scans each line from the first line at the top to the last line at the bottom, from the first dot at the leftmost to the last dot at the rightmost of each line. In the example shown in Fig. 10, the generated image data D40 includes an image D41 of a page or object, and a blank candidate portion R41 where the image D41 is not formed. The blank candidate portion R41 is a portion that may be a blank portion R42.

[0074] The method for detecting the blank candidate portion R41 is as follows. (1) For the upper part of the generated image data D40, the blank detection unit 36 ​​checks whether or not the dots in the first line are painted. If all the dots in the first line are not painted, the unpainted dots become blank candidate parts R41. (2) For the left part of the generated image data D40, the blank detection unit 36 ​​checks whether the first dot of each line is painted. If the first dot of all lines is not painted, the unpainted dot portion becomes a blank candidate portion R41. (3) For the right part of the generated image data D40, the blank detection unit 36 ​​checks whether the last dot of each line is painted. If the last dot of all lines is not painted, the unpainted dot portion becomes a blank candidate portion R41. (4) For the lower part of the generated image data D40, the blank detection unit 36 ​​checks whether the dots on the last line are painted. If all the dots on the last line are not painted, the unpainted dots become blank candidate parts R41.

[0075] Returning to FIG. 9, after step S205, the blank area detection unit 36 ​​determines whether blank area candidate portions R41 were detected above, below, left, or right of the generated image data D40 (FIG. 10) in step S205 (step S210).

[0076] If it is determined in step S210 that a blank candidate portion R41 has been detected (if "Yes"), the blank detection unit 36 ​​compares the generated image data D40 with the size data of the corresponding page of the registered print job data D50 (FIG. 11) registered in the database DB and the object if the corresponding page includes an object (step S215).Then, the blank detection unit 36 ​​executes a blank detection process (step S220).

[0077] After step S220, the blank area detection unit 36 ​​judges whether or not a blank area R42 (FIG. 11) is present (step S225). The judgment of whether or not a blank area R42 (FIG. 11) is present is made, for example, when the condition shown in FIG. 12 is satisfied. The condition shown in FIG. 12 will be described later.

[0078] If it is determined in step S225 that there is a blank portion R42 (FIG. 11) (if "Yes"), the warning notification unit 37 displays a warning notification screen I11 (FIG. 4) on the display unit 61 to notify the user of a warning (step S235). This ends the series of routine processes shown in FIG.

[0079] If it is determined in the above-mentioned step S210 that the blank candidate portion R41 has not been detected (if "No"), the process proceeds to step S230. Also, if it is determined in the above-mentioned step S225 that the blank portion R42 (FIG. 11) does not exist (if "No"), the process also proceeds to step S230. In these cases, the blank detection unit 36 ​​determines whether or not the processing has been completed for the generated image data D40 of all pages (step S225).

[0080] If it is determined in step S225 that processing has been completed for the generated image data D40 of all pages (if "Yes"), the series of routine processing shown in Fig. 9 ends. On the other hand, if it is determined in step S225 that processing has not been completed for the generated image data D40 of all pages (if "No"), the process returns to step S210.

[0081] The method of matching the generated image data D40 in step S215 with the size data of the corresponding page of the registered print job data D50 and the object if the corresponding page includes an object is as follows.

[0082] The collation method will be described below with reference to Fig. 11 and Fig. 12. Fig. 11 is an explanatory diagram of collation of size data of generated image data D40 generated from print job data with size data of a corresponding page of registered print job data D50 registered in database DB and size data of an object included in the corresponding page.

[0083] As shown in Fig. 11, the blank detection unit 36 ​​compares the size data of the generated image data D40 (Fig. 10) with the size data of the corresponding page of the print job data D11 (registered print job data D50) registered in the database DB, and with the size data of the object when the object is included in the corresponding page. In the registered print job data D50, each object is defined in units of points, for example. Therefore, the blank detection unit 36 ​​converts each object from units of points to units of dots and compares them. This point will be described later.

[0084] In the example shown in Fig. 11, the registered print job data D50 includes a page image D51. The page image D51 of the registered print job data D50 differs from the image D41 of the generated image data D40 (Fig. 10) in the following points.

[0085] 10, in image D41 of generated image data D40, no page image is present in all dots in the first line at the top, the first dot of each line at the left, the last dot of each line at the right, and all dots in the last line at the bottom. Whiteout detection unit 36 ​​detects these parts of image D41 of generated image data D40 as whiteout candidate parts R41.

[0086] In contrast, in page image D51 of registered print job data D50, page images exist in all dots of the first line at the top, the first dot of each line at the left, and all dots of the last line at the bottom, but no page image exists only in the last dot of each line at the right.

[0087] The blank area detection unit 36 ​​detects a portion where no page image exists in the page image D51 of the registered print job data D50 as a blank area R42. Also, the blank area detection unit 36 ​​detects a portion where a page image exists in the blank area candidate portion R41 of the page image D51 of the registered print job data D50 as a filled-in portion R44.

[0088] In the example shown in FIG. 11, the registered print job data D50 includes object images D52a and D52b.

[0089] The object image D52a is formed in a rectangular shape with a vertical width WD52a and a horizontal width LD52a from a start position coordinate SD52a. All dots of the object image D52a are arranged inside the page image D51.

[0090] On the other hand, the object image D52b is formed in a rectangular shape with a vertical width WD52b and a horizontal width LD52b from the start position coordinate SD52b. The object image D52b is arranged so that the final dot of each line on the right side protrudes from the page image D51. Therefore, in the registered print job data D50, the object image exists in a part of the final dot of each line on the right side.

[0091] The blank area detection unit 36 ​​detects a portion of the blank area candidate portion R41 where an object image exists as a filled-in portion R44 for the object image D52b of the registered print job data D50. Here, "a portion of the blank area candidate portion R41 where an object image exists" means a portion of the blank area candidate portion R41 where the object image D52b protrudes from the page image D51. Also, a portion of the blank area candidate portion R41 where an object image does not exist is detected as a blank area R42.

[0092] When comparing the size data of the generated image data D40 (FIG. 10) with the size data of the corresponding page (page image D51) of the print job data D11 (registered print job data D50), blank area detection unit 36 ​​compares them based on the origin O set in the upper left corner. When comparing the size data of the generated image data D40 (FIG. 10) with the size data of an object included in the corresponding page (page image D51), blank area detection unit 36 ​​acquires size data, for example, as shown in FIG. 8, based on the start position coordinates and the vertical and horizontal widths of the object. Then, blank area detection unit 36 ​​compares the size data of the generated image data D40 (FIG. 10) with the acquired size data of the object.

[0093] (Method of verification) As described above, in the registered print job data D50 (PDL data), each object is defined, for example, in units of points. Therefore, the blank detection unit 36 ​​converts each object from units of points to units of dots and compares them. The conversion from units of points to units of dots is calculated using the following formula (1). Points ÷ 72 × resolution = dots … (1)

[0094] Here, let us assume that the resolution of the generated image data D40 is n [dpi: dots per inch], and that the position coordinates of the generated image data D40 are (Ph, Pv) dots. Let us also assume that the start position coordinates of the object are (x, y) points, and the size is (h, v) points. In this case, the conversion from points to dots for the start position coordinates of the object can be found using the following equations (2) and (3). Moreover, the conversion from points to dots for the size of the object can be found using the following equations (4) and (5). About the starting position coordinate (x,y) point x÷72×n=dotx(dot) …(2) y÷72×n=doty (dot) …(3) About size (h,v) points h÷72×n=doth (dot) …(4) v÷72×n=dotv(dot) …(5)

[0095] When a blank portion R42 is detected in each portion of the generated image data D40, the blank detection unit 36 ​​executes a blank detection process by collating an object of the corresponding page from the database DB as follows.

[0096] Fig. 12 is an explanatory diagram of the matching methods and conditions. In Fig. 12, the first to fourth rows show the matching methods and conditions for "left detection", "upper detection", "right detection", and "lower detection", respectively.

[0097] For example, the first row ("Left detection") shows the matching method "when the X coordinate dotx of the object's starting position is 0, no blank areas will occur" and the condition "dotx=0".

[0098] In addition, the second row (the "Upper detection" column) shows the matching method that "if the difference between the Y coordinate doty of the object's starting position and the height dotv is 0, no white space will be generated" and the condition "doty-dotv=0".

[0099] In addition, the third row (the "Right Detection" column) shows the matching method that "if the sum of the X-coordinate dotx of the object's starting position and its width doth is equal to or greater than the X-coordinate Ph of the page image, no blank areas will occur," along with the condition "dotx+doth>0."

[0100] In addition, the fourth row ("Bottom Detection" column) shows the matching method that "if the Y coordinate doty of the object's starting position is equal to or greater than the Y coordinate Pv of the page image, no white space will occur," along with the condition "doty≧Pv."

[0101] <Image extension section operation> When it is determined in step S150 of FIG. 3 that the filling process has been selected (i.e., the "Perform filling" button has been pressed on the warning notification screen I11 shown in FIG. 4), the image forming device 103 executes the filling process using the image expansion unit 38 in step S155 of FIG. 3.

[0102] The operation of the image extension unit 38 in this case will be described below with reference to Figs. 13A and 13B. Figs. 13A and 13B are explanatory diagrams of the operation of the image extension unit 38. Fig. 13A shows the detection points and filling methods of "(1) left part", "(2) upper part", "(3) right part", and "(4) lower part" from the first row to the fourth row, respectively. Fig. 13B also shows the detection points and filling methods of "(5) upper left corner", "(6) lower left corner", "(7) upper right corner", and "(8) lower right corner" from the first row to the fourth row, respectively.

[0103] For example, the first row of Figure 13A (column "(1) Left") shows a filling method in which "the adjacent portion R43 of image 41 adjacent to the right side of the blank portion R42 is extended to the left to fill in the blank portion R42."

[0104] Furthermore, the second row of Figure 13A (column "(2) Upper part") shows a filling method in which "the white-out portion R42 is filled in by extending the adjacent portion R43 of the image 41 adjacent to the lower side of the white-out portion R42 upward."

[0105] Furthermore, the third row of Figure 13A (column "(3) Right") shows a filling method in which "the white-out portion R42 is filled in by extending the adjacent portion R43 of the image 41 adjacent to the left side of the white-out portion R42 to the right."

[0106] Furthermore, the fourth row of Figure 13A (column "(4) Lower part") shows a filling method in which "the white-out portion R42 is filled in by extending downward the adjacent portion R43 of the image 41 adjacent to the upper side of the white-out portion R42."

[0107] Furthermore, the first row of Figure 13B (column "(5) Upper left corner") shows a filling method in which "the adjacent portion R43 of the image 41 adjacent to the three gaps R42 in the upper left corner is expanded diagonally upward to the left, upward, and to the left, thereby filling in the gaps R42."

[0108] Furthermore, the second row of Figure 13B (column "(6) Lower Left Corner") shows a filling method in which "the adjacent portion R43 of the image 41 adjacent to the three gaps R42 in the lower left corner is expanded diagonally downward to the left, downward, and to the left, thereby filling in the gaps R42."

[0109] Furthermore, the third row of Figure 13B (column "(7) Upper right corner") shows a filling method in which "the adjacent portion R43 of the image 41 adjacent to the three gaps R42 in the upper right corner is expanded diagonally upward to the right, upward, and to the right, thereby filling in the gaps R42."

[0110] Furthermore, the fourth row of Figure 13B (column "(8) Lower right corner") shows a filling method in which "the adjacent portion R43 of the image 41 adjacent to the three gaps R42 in the lower right corner is expanded diagonally downward to the right, downward, and to the right, thereby filling in the gaps R42."

[0111] In this configuration, the image forming apparatus 103 can also erase streaks 81a (FIG. 14A) formed on roll paper by performing a process to fill in blank areas R42. Below, the erasure of streaks 81a (FIG. 14A) will be explained with reference to FIGS. 14A and 14B. FIG. 14A is an explanatory diagram of streaks 81a formed on roll paper. FIG. 14B is an explanatory diagram of the erasure of streaks 81a.

[0112] As shown in Fig. 14A, when processing is not performed to fill in blank areas R42 between page images, streaks 81a are formed in printed image 81 formed on roll paper. In contrast, when processing is performed by image expansion unit 38 to fill in blank areas R42 between page images as shown in Fig. 14A, image forming device 103 can erase streaks 81a shown in Fig. 14A from printed image 82 formed on roll paper.

[0113] <Main features of image forming equipment> (1) As shown in Fig. 2, an image forming apparatus 103 according to this embodiment includes a control unit 10 that controls the operation of each unit, and an image forming unit (printing unit 72) that forms an image on a print medium 106. The control unit 10 includes an image data generating unit 31 and a blank area detecting unit 36. The image data generating unit 31 is a component that generates image data D12 (raster data) based on print job data D11 (PDL data). The blank area detecting unit 36 ​​is a component that detects blank areas in edge portions R12 (Fig. 5) of the image data D12 based on size data of the image data D12.

[0114] The image forming apparatus 103 according to this embodiment can efficiently (that is, quickly and accurately) detect blank areas at the edges of generated image data, and can easily take measures to deal with the blank areas. The image forming apparatus 103 according to this embodiment can reduce the defective rate of print jobs and reduce printing costs by suppressing the occurrence of blank areas in advance or by having the user check for them.

[0115] (2) As shown in Fig. 2, the image forming apparatus 103 according to this embodiment has a database DB that stores various data. At least size data of image data D12 included in print job data D11 is registered in the database DB. As shown in step S135 in Fig. 2, the blank area detection unit 36 ​​may detect blank areas at the edges of the generated image data by comparing the size data of the generated image data generated by the image data generation unit 31 with the size data of the corresponding page of the print job data D11 (registered print job data D50) registered in the database DB and the size data of the object when the corresponding page includes an object.

[0116] The image forming device 103 of this embodiment can efficiently (i.e., quickly and accurately) detect white areas at the edges of the generated image data by comparing the size data of the generated image data with the size data of the corresponding page in the registered print job data D50 and the size data of the object if the object is included on the corresponding page.

[0117] (3) As shown in Fig. 2, in the image forming apparatus 103 according to this embodiment, the control unit 10 may further include a data processing unit 34 (a data inspection unit 32 and a data registration unit 33). The data processing unit 34 is a component that deletes any data portion below the decimal point from the size data of the image data D12 included in the print job data D11.

[0118] The image forming apparatus 103 according to this embodiment can suppress the occurrence of floating point calculation errors when generating print job data D11 (raster data) from print job data D11 (PDL data). As a result, the image forming apparatus 103 according to this embodiment can reduce the occurrence of blank areas.

[0119] (4) In the image forming apparatus 103 according to this embodiment, the data processing unit 34 (the data inspection unit 32 and the data registration unit 33) may delete any data portion after the decimal point from the size data of the image data D12 so as to suppress the occurrence of errors in floating-point calculations performed when the image data generation unit 31 generates the image data D12. In this embodiment, the data processing unit 34 is configured to delete the data portion after the third decimal place.

[0120] The image forming apparatus 103 according to this embodiment deletes data portions of the size data of the image data D12 that are below the third decimal place and for which calculation accuracy is not guaranteed. This allows the image forming apparatus 103 according to this embodiment to suppress occurrence of floating point calculation errors when generating print job data D11 (raster data) from print job data D11 (PDL data). This allows the image forming apparatus 103 according to this embodiment to reduce occurrence of blank areas.

[0121] (5) As shown in Fig. 2, in the image forming apparatus 103 according to this embodiment, the control unit 10 may further include an image expansion unit 38. The image expansion unit 38 is a component that expands an adjacent portion adjacent to a blank portion to fill in the blank portion.

[0122] When a blank portion is detected, the image forming apparatus 103 according to this embodiment can erase the blank portion by expanding the adjacent portion adjacent to the blank portion and filling in the blank portion.

[0123] (6) As shown in Fig. 2, in the image forming apparatus 103 according to the present embodiment, the control unit 10 may further include a warning notification unit 37. The warning notification unit 37 is a component that notifies a user of a warning when a blank portion is detected.

[0124] The image forming apparatus 103 according to this embodiment can notify the user when a blank portion is detected, thereby informing the user of the existence of the blank portion and accepting suggestions from the user on how to deal with the problem.

[0125] (7) As shown in Fig. 4, in the image forming apparatus 103 according to this embodiment, when a blank portion is detected, the warning notification unit 37 may display a warning notification screen I11 on the display unit 61. The warning notification screen I11 is a screen including a selection button for executing printing, a selection button for performing a process of filling in the blank portion by expanding an adjacent portion adjacent to the blank portion, and a selection button for canceling printing.

[0126] When a blank portion is detected, the image forming apparatus 103 according to this embodiment allows the user to select one of the buttons to be pressed, thereby selectively executing printing, filling in the blank portion, or canceling printing.

[0127] (8) As shown in Fig. 2, in the image forming apparatus 103 according to the present embodiment, the control unit 10 may further include a selection processing unit 39. The selection processing unit 39 is a component that, when a blank portion is detected, receives a method of dealing with the blank portion selected by the user.

[0128] When a blank portion is detected, the image forming apparatus 103 according to this embodiment can accept a solution from the user.

[0129] (9) As shown in FIG. 1, in the image forming apparatus 103 according to this embodiment, roll paper can be used as the printing medium 106, and it is preferable to include a roll paper feed unit (print medium feed unit 104) that feeds the roll paper downstream, and a roll paper receiving unit (print medium receiving unit 105) that receives the roll paper fed by the roll paper feed unit.

[0130] When roll paper is used as the print medium 106, the image forming apparatus 103 according to this embodiment can prevent streaks from appearing at the boundaries between page images.

[0131] (10) As shown in FIG. 3, the control method of image forming apparatus 103 according to this embodiment may include a step of acquiring print job data D11 (step S105), a step of registering size data of image data D12 included in print job data D11 in database DB (step S115), a step of generating image data D12 based on print job data D11 (step S130), and a step of detecting blank areas at the edges of the generated image data by comparing the size data of the generated generated image data with size data of a corresponding page of print job data D11 (registered print job data D50) registered in database DB and size data of the object if the corresponding page includes an object (step S135).

[0132] The control method of the image forming apparatus 103 according to this embodiment can efficiently detect blank areas at the edges of the generated image data and facilitate the implementation of measures to deal with the blank areas. The control method of the image forming apparatus 103 according to this embodiment can reduce the defective rate of print jobs and reduce printing costs by suppressing the occurrence of blank areas in advance or by having the user check for them.

[0133] (11) As shown in FIG. 3, in the control method for image forming apparatus 103 according to this embodiment, in the process of registering size data in database DB (step S115), a process of deleting any data portion of the size data after the decimal point may be performed.

[0134] The control method of the image forming apparatus 103 according to this embodiment can suppress the occurrence of floating point calculation errors when generating print job data D11 (raster data) from print job data D11 (PDL data). As a result, the image forming apparatus 103 according to this embodiment can reduce the occurrence of blank areas.

[0135] (12) As shown in FIG. 3, the control method for the image forming apparatus 103 according to this embodiment may further include a step (step S145) of notifying a user of a warning when a whiteout portion is detected at the edge of the generated image data.

[0136] The control method of the image forming apparatus 103 according to this embodiment can inform the user of the existence of a blank portion by notifying the user when a blank portion is detected, and can accept suggestions from the user on how to deal with the problem.

[0137] (13) As shown in FIG. 3, the method for controlling image forming apparatus 103 according to this embodiment may further include a step (step S150) of performing a process for prompting a user to select a method for dealing with a blank portion when a blank portion is detected at an edge portion of the generated image data.

[0138] The control method of the image forming apparatus 103 according to this embodiment allows the user to select a method of dealing with a case where a blank portion is detected.

[0139] (14) As shown in FIG. 3, the control method for image forming apparatus 103 according to this embodiment may further include a step (step S155) of expanding an adjacent portion adjacent to a blank portion when a blank portion is detected at an edge portion of the generated image data to fill in the blank portion.

[0140] In the control method of the image forming apparatus 103 according to this embodiment, when a whiteout portion is detected, the whiteout portion can be erased by expanding the adjacent portion adjacent to the whiteout portion and filling in the whiteout portion.

[0141] (15) As shown in FIG. 3, the control program Pr of this embodiment may be configured to cause the control unit 10 of either the image forming apparatus 103 or the information processing apparatus (not shown) to execute the steps of acquiring print job data D11 (step S105), registering size data of image data D12 included in the print job data D11 in the database DB (step S115), generating image data D12 based on the print job data D11 (step S130), and comparing the size data of the generated generated image data with size data of a corresponding page of the print job data D11 (registered print job data D50) registered in the database DB and size data of the object if the corresponding page contains an object, thereby detecting whiteout portions at the edges of the generated image data (step S135).

[0142] Such a control program Pr can provide an image forming apparatus 103 that efficiently detects blank areas at the edges of generated image data and makes it easy to take measures against the blank areas.

[0143] As described above, the image forming apparatus 103 according to the embodiment can efficiently (that is, quickly and accurately) detect blank areas during image formation, making it easier to take measures against the blank areas. Therefore, the image forming apparatus 103 according to the present embodiment can reduce the defective rate of print jobs and reduce printing costs by suppressing the occurrence of blank areas in advance or by having the user check them.

[0144] The present invention is not limited to the above-described embodiment, and various changes and modifications can be made without departing from the gist of the present invention.

[0145] For example, the above-described embodiment has been described in detail to clearly explain the gist of the present invention. Therefore, the present invention is not necessarily limited to having all of the components described. In addition, the present invention can be modified by adding other components to certain components, or by replacing some components with other components. In addition, the present invention can be modified by deleting some components.

[0146] Also, for example, the image forming apparatus 103 may be configured so that the data processing unit 34 (data inspection unit 32 and data registration unit 33) corrects the size data of the image data (raster data) when a blank portion is detected by the blank portion detection unit 36. In this case, the data processing unit 34 (data inspection unit 32 and data registration unit 33) may be configured to correct (delete) any data portion below the decimal point in the size data of the image data (raster data) so as to suppress errors in floating point calculations performed when the image data generation unit 31 generates the image data (raster data). The image forming apparatus 103 configured in this manner can efficiently suppress the occurrence of blank portions. [Explanation of symbols]

[0147] 10 Control section 20 Memory section 31 Image data generation unit 32 Data Inspection Department 33 Data Registration Department 34 Data Processing Section 36 Whiteout detection section 37 Warning Notification Section 38 Image Extension 39 Selection processing section 60 Operation Panel 61 Display section 100 Image forming system 103 Image forming device D11 Print job data (PDL data) D12 Image data (raster data) D20 Size Data D21 Page size data D22 Object Size Data D30 Size data before deletion D31 Deleted data D32 Size data after deletion D40 Generated image data (raster data) D41 Images D50 Registered print job data (PDL data) D51 Page Image D52a, D52b object images DB Database Pr control program R11 Print area R12 Edge R13 White area R41 Whiteout candidate area R42 White area R43 Adjacent part R44 Filled area (extended area)

Claims

1. A control unit that controls the operation of each unit; an image forming unit that forms an image on a print medium, The control unit is an image data generating unit that generates image data based on the print job data; a blank area detection unit that detects blank areas at edges of the image data based on size data of the image data, 1. An image forming apparatus comprising:

2. A database for storing various data is provided. The database registers size data of at least the image data included in the print job data, the blank area detection unit detects blank areas at the edges of the generated image data by comparing size data of the generated image data generated by the image data generation unit with size data of a corresponding page of the registered print job data registered in the database and size data of an object when the corresponding page includes an object.

2. The image forming apparatus according to claim 1,

3. The control unit further includes a data processing unit that deletes any data portion after a decimal point from size data of the image data included in the print job data.

2. The image forming apparatus according to claim 1,

4. the data processing unit deletes a data portion below an arbitrary decimal point from size data of the image data so as to suppress occurrence of an error in floating point calculation performed when the image data generating unit generates the image data.

4. The image forming apparatus according to claim 3.

5. The control unit further includes an image expansion unit that expands an adjacent portion adjacent to the blank portion to fill in the blank portion.

2. The image forming apparatus according to claim 1,

6. The control unit further includes a warning notification unit that notifies a user of a warning when the blank portion is detected.

2. The image forming apparatus according to claim 1,

7. the warning notification unit causes a display unit to display a screen including a selection button for executing printing, a selection button for performing a process of filling in the blank portion by expanding an adjacent portion adjacent to the blank portion, and a selection button for canceling printing when the blank portion is detected.

7. The image forming apparatus according to claim 6,

8. the control unit further includes a selection processing unit configured to accept a method of dealing with the blank portion selected by a user when the blank portion is detected.

2. The image forming apparatus according to claim 1,

9. The printing medium may be roll paper. a roll paper feed section that feeds the roll paper downstream; a roll paper receiving section for receiving the roll paper fed by the roll paper feeding section.

2. The image forming apparatus according to claim 1,

10. A control method for an image forming apparatus, comprising: obtaining print job data; registering size data of the image data included in the print job data in a database; generating image data based on the print job data; and detecting blank areas at the edges of the generated image data by comparing size data of the generated image data with size data of a corresponding page of the registered print job data registered in the database and size data of the object when the corresponding page includes an object. 2 is a control method for an image forming apparatus according to claim 1 .

11. In the step of registering the size data in the database, a process of deleting any data portion below the decimal point of the size data is performed. The method for controlling an image forming apparatus according to claim 10 .

12. Further, the method includes a step of notifying a user of a warning when a whiteout portion is detected at an edge portion of the generated image data. The method for controlling an image forming apparatus according to claim 10 .

13. Further, when a blank portion is detected at an edge portion of the generated image data, a process of prompting a user to select a method for dealing with the blank portion is included. The method for controlling an image forming apparatus according to claim 10 .

14. Further, when a blank portion is detected at an edge portion of the generated image data, the process includes a step of expanding an adjacent portion adjacent to the blank portion to fill in the blank portion. The method for controlling an image forming apparatus according to claim 10 .

15. A control unit of either the image forming apparatus or the information processing apparatus, obtaining print job data; registering size data of the image data included in the print job data in a database; generating image data based on the print job data; A program for executing a process of comparing size data of the generated generated image data with size data of the corresponding page of registered print job data registered in the database and size data of the object if the corresponding page contains an object, and detecting white areas at the edges of the generated image data.

Images