JP4788511B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus that executes booklet printing.

  2. Description of the Related Art Conventionally, there has been known an image forming apparatus that executes booklet printing for producing a booklet (booklet) formed by overlapping a plurality of sheets printed on two pages on the front and back surfaces and folding the sheet into two. .

  Note that in booklet printing, as shown in FIG. 6, the image data for four pages printed on one sheet of recording paper does not have continuous pages. It is necessary to execute composition (in the figure, when the total number of printed sheets is N).

  Accordingly, in general, the image forming apparatus stores all image data (one page of all pages) to be booklet printed in the memory, and then starts processing (sorting and combining image data). Have been to.

In particular, when booklet printing is performed using a printer dedicated to single-sided printing, guidance is given to print an image on the back side after printing on one side, and the user changes the print side of the printing paper. Booklet printing is also performed (see, for example, Patent Document 1).
JP 2003- 211774 A

  By the way, in the image forming apparatus that performs booklet printing, as described above, an image memory having a capacity sufficient to store all image data for one booklet is required, which not only makes the apparatus expensive. When the image data exceeds the memory capacity, booklet printing cannot be executed, so that the total number of pages that can be booklet printed is limited.

  In addition, if booklet printing is performed by normal printing such that printing is performed in the order in which image data is acquired without using such a function of automatically rearranging image data, image data for all pages is stored in the memory. Since there is no need to store, the total number of pages that can be booklet printed is not limited.

  However, in this case, it is necessary for the user to rearrange the order (page order) of the image data to be acquired by the printer, and there is a problem that it takes a lot of trouble for a user who is not used to booklet printing.

  SUMMARY OF THE INVENTION In order to solve the above problems, it is a first object of the present invention to provide an image forming apparatus capable of reducing the memory capacity for storing image data for booklet printing. It is a second object of the present invention to provide an image forming apparatus that can greatly reduce the trouble of manual replacement.

The image forming apparatus according to claim 1, wherein the image forming apparatus is configured to acquire a total number of pages of image data, an image acquisition unit that acquires the image data, and the image acquisition unit. Storage means for storing the image data acquired by the above, a printing means for printing the image data stored in the storage means, and a plurality of sheets each printed on the front and back surfaces for two pages are overlapped and folded in two. A pagelet printing page layout executed to create a bound booklet based on the total number of pages acquired by the page number acquisition unit; and the determination unit was in accordance with the page layout, as image data to be printed on the same paper is continuous, the image data is broadcast the page order to be acquired by the image acquiring unit, the broadcast pages order As an image data is acquired by the image acquiring unit, a first control means for executing printing on the printing unit in order of the image data to be printed on the same sheet is aligned in the storage unit, the page order of the document Assuming that the image data is acquired by the image acquisition means, when 2N + 2 pages worth of image data (where N is the number of prints calculated from the total number of pages) is stored in the storage means, A second control unit that executes booklet printing; a calculation unit that obtains a free space in the storage unit and calculates the number of pages that can be stored in the free space; and the number of pages calculated by the calculation unit is 2N + 2 pages. If the number of pages calculated by the calculation means is 2N + 2 or more, control by the second control means is started. Characterized by comprising a starting means for.

According to the image forming apparatus of the present invention configured as described above, when there is no free space for storing 2N + 2 pages of image data in the storage unit, the control by the first control unit is started, and the storage is performed. Even if the means does not have a capacity for storing image data for the total number of pages, if it has a capacity for storing all image data (for four pages) to be printed on one sheet, booklet printing is performed. Can be executed. If the storage means has a sufficient capacity for storing image data for 2N + 2 pages, the control by the second control means is started, so that the second control means does not bother the user. Booklet printing can be performed.

In particular, in the control by the first control means , the page order of the image data to be acquired by the image acquisition means is notified, so the user may acquire the image data by the image acquisition means in the notified page order, Since it is not necessary to worry about the head, the labor required for rearranging the image data can be greatly reduced, and as a result, booklet printing can be easily performed.

  It is preferable that the page order of the image data notified by the first control unit is set so that image data to be printed on the same surface of the same sheet is continuous. .

  According to the image forming apparatus of the present invention configured as described above, when the printing unit is configured to perform printing on one side at a time, all of the data to be printed on one side of one sheet (for two pages). The booklet printing can be executed if the image data has a capacity sufficient to store the image data.

By the way, as described in claim 3, the image forming apparatus of the present invention may include an update unit that updates the notification contents every time the image data is acquired by the image acquisition unit. According to a fourth aspect of the present invention, the first control unit may be configured to collectively notify the page order of the image data to be acquired by the image acquisition unit for a plurality of pages. .

  In the case of the former (Claim 3), the original (image data) to be read by the image reading means is set manually (one page) at a time, like an FB (flatbed) type image reading means. In the latter case, the document to be read by the image reading means is automatically and continuously conveyed to the document reading position by an ADF (automatic document feeder). It is suitable when it is configured as described above.

The image forming apparatus of the present invention, as described in claim 5, wherein the starting means, when the number of pages calculated by the calculating means is less than 2N + 2 pages, control by the first control means Or you may provide the selection means which makes a user select which of the control by a said 2nd control means is started .

  In other words, when the size of individual image data is not constant, such as when the image data is compressed, there is a possibility that image data of the number of pages or more calculated by the calculation means can be stored in the storage means. Even if the number of printed pages is smaller than 2N + 2 pages, there is a possibility that booklet printing without notification by the second control means can be executed. Therefore, in such a case, the user's effort can be reduced as much as possible by making the user select.

Furthermore, the image forming apparatus of the present invention, as described in claim 6, during execution of control by the second control means, when the free capacity of the storage means is equal to or less than a predetermined capacity, the storage means Switching to the control by the first control means when the total number of pages of image data already stored in the page and the number of pages of image data that can be stored in the free capacity of the storage means is less than 2N + 2 pages. Means may be provided.

  According to the image forming apparatus of the present invention configured as described above, even when it becomes clear that the image data for 2N + 2 pages cannot be stored in the storage unit during the execution of the control by the second control unit, Thus, it is possible to continue the booklet printing by switching to the control by the first control means, and to further improve the convenience of the apparatus.

  When the predetermined capacity is set to a size that cannot store image data for one page, when switching to the first control means and storing new image data, new image data is added to the already stored image data. Overwriting and overwritten image data must be handled as unread image data, and extra control is required.

Therefore, it is desirable that the predetermined capacity is a size capable of storing image data for at least two pages, as described in claim 7 .
In this case, new image data can be stored without overwriting previously stored image data, and control when switching to the first control means to continue printing can be simplified.

In addition, when switched to the control by the first control unit by the switching unit, as described in claim 8 , the first control unit is acquired by the image acquisition unit only for unread image data. It is desirable to notify the page order.

  That is, since notification of unnecessary information that has already been read is omitted, the notification content can be provided in a format that is easily recognized by the user.

Embodiments of the present invention will be described below with reference to the drawings.
<Overall configuration of image forming apparatus>
FIG. 1 is a block diagram showing a configuration of an image forming apparatus 1 to which the present invention is applied.

The image forming apparatus 1 according to the present embodiment is configured as a so-called multi-function machine having functions as a printer, a scanner, a copier, and a FAX.
As shown in FIG. 1, an image forming apparatus 1 includes an image forming unit 3 as an example of a printing unit that prints image information on a printing medium such as paper, and an example of an image acquisition unit that reads image information recorded on a document. As an image reading unit 4, cursor keys and switches for inputting various settings and commands, and a menu screen on which various menu items are displayed, and a display for various information input by the user and various notifications to the user A network interface (I / F) 6 for inputting / outputting image data between an operation panel 5 including a liquid crystal panel or the like and an external device (for example, a personal computer) via a communication network such as a LAN. A facsimile communication unit 7 for communicating image data via a general public line, a card slot for mounting various storage media, etc. An external memory card I / F 8 and a control unit 10 that realizes functions as a printer, a scanner, a copier, and a FAX by controlling each part of the apparatus in accordance with commands and settings input via the operation panel 5. It has.

  The image reading unit 4 includes a so-called flat bed that includes a main body that reads information from a document placed on the reading surface, and a cover that can be closed so as to cover the reading surface and that can be opened and closed on the main body. (FB) type. The image reading unit 4 automatically and continuously conveys the document placed on the predetermined document placing unit to the reading surface, and discharges the document to the predetermined document collecting unit after reading the image data. A known automatic document feeder (ADF) is provided.

  In addition, since the image forming unit 3, the operation panel 5, the network I / F 6, the facsimile communication unit 7, and the external memory card I / F 8 are well-known, detailed description thereof is omitted.

  However, the image forming unit 3 is configured to be capable of duplex printing, and the operation panel 5 is provided with at least a Start key that is operated when the image reading unit 4 starts reading. In addition, at least a command for executing booklet printing can be input.

  Next, the control unit 10 is configured around a well-known microcomputer including a CPU 11, a ROM 12, and a RAM 13, and further includes an EEPRM 14 that stores various setting information and the like that should be retained even when the power is turned off, and each unit 3-8. And an I / O control unit 15 for controlling input / output of various signals to / from.

Note that the RAM 13 is an example of a storage unit that stores compressed image data that is input via the image reading unit 4, the network I / F 6, the facsimile communication unit 7, and the external memory card I / F 8 in units of pages. At least the buffer area is secured.
<About booklet printing>
Next, booklet printing processing executed by the CPU 11 will be described with reference to the flowcharts shown in FIGS.

This process is started when a booklet printing execution command is input via the operation panel 5 to the image reading unit 4 as an image data acquisition destination.
When this processing is started, as shown in FIG. 2, first, in S110, an original number input instruction display for instructing input of the number of originals (total number of pages of image data) P for booklet printing is displayed via the operation panel 5. In subsequent S120, the process waits until the number of originals P is input via the operation panel 5.

If the number of originals P is input, the process proceeds to S130, the page layout for booklet printing is determined according to the input original number P, and the process proceeds to S140.
Specifically, in determining the page layout, first, the total number N of prints is calculated based on the acquired number of originals P, and then n (n = 1, 2,...) As shown in FIG. , N) pages are assigned 2n-1, 2n, 4N-2 (n-1), 4N-2 (n-1) -1 pages.

  Note that the total number of printed sheets N is a value obtained by dividing the number of original sheets P by 4 which is the number of pages printed per sheet, and rounding up the decimals. P is one of 4N-3, 4N-2, 4N-1, and 4N. However, if it is set via the operation panel 5 so as to print a standard cover and back cover prepared in advance separately from the original to be acquired, the number of originals inputted in S120 +2 is the number of originals. P.

  In S140, the free space in the buffer area of the RAM 13 is acquired, and in subsequent S150, the number of pages that can be stored in the acquired free space (hereinafter referred to as “the number of pages that can be stored”) is calculated, and the process proceeds to S160.

  The number of pages that can be stored is, for example, calculated as a unit page size obtained by compressing image data for one page composed only of characters. However, the present invention is not limited to this, and the average size of compressed image data may be used as the unit page size.

  In S160, based on the number of storable pages and the total number N of prints, it is determined whether or not there is a possibility that the free capacity of the buffer area will be insufficient (hereinafter referred to as “memory shortage”). Specifically, if the storable page number is smaller than the print start page number SP (= 2N + 2) set from the total print number N, it is determined that there is a possibility of memory shortage.

  If 2N + 2 pages worth of image data can be stored, at least all the image data (2N-1 pages, 2N pages, 2N + 1 pages, 2N + 2 pages) to be printed on the Nth sheet in FIG. Because it can start.

  If it is determined in S160 that there is a possibility of memory shortage, the process proceeds to S170, and a warning display for notifying that and manual rearrangement according to the page layout for booklet printing are performed manually. Display to let the user select whether to do it automatically.

  In subsequent S180, it is determined whether the selection input by the user via the operation panel 5 is “manual” or “automatic”. If it is “manual”, the process proceeds to S190, and the original order manual setting printing described later is performed. The process is executed and the present process is terminated.

  On the other hand, if it is determined that there is no possibility of memory shortage in the previous S160, or if the selection input by the user is “automatic” in the previous S180, the process proceeds to S200, and the document order automatic described later is performed. The setting print process is executed, and this process ends.

  In other words, in this process, if there is sufficient free space in the buffer area, the document order automatic setting print is executed, and there is a possibility that the free space necessary for executing the document order automatic setting print may not be secured. In addition to displaying a warning to that effect, the user is allowed to select whether the document is rearranged manually (manual order manual setting process) or automatically (original order automatic setting process). .

In this process, S110 to S120 are examples of page number acquisition means, S130 is an example of determination means, S140 to S150 are examples of calculation means, S160 and S180 are examples of start means, and particularly S180 is an example of selection means, S190 is an example of the first control unit, and S200 is an example of the second control unit.
<Manual setting manual printing>
Next, details of the document order manual setting print processing executed in S190 will be described with reference to the flowchart shown in FIG.

  When this process is started, as shown in FIG. 3, first, in S300, the page order of the document to be acquired by the image reading unit 4 is set in accordance with the page layout determined in S130. Specifically, it is set so that four pages of originals printed on the same recording paper are continuous, and further, originals printed on the same side are continuous. That is, two pages of originals printed on the front surface of the first recording paper, two pages of originals printed on the back side of the recording paper, and two pages printed on the front surface of the second recording paper Are arranged in the order of two originals printed on the back side of the recording paper (hereinafter the same).

  For example, when booklet printing is executed with 12 originals P1 to P12 (the nth original is Pn), as shown in FIG. 5, the original P1 is printed in order from the original printed on the first recording sheet. , P12, P2, P11, P3, P10, P4, P9, P5, P8, P6, P7.

  In S310, it is determined whether or not the ADF is used when the image reading unit 4 reads the document. This determination is made, for example, by referring to setting information set by the user via the operation panel 5.

  If it is determined in S310 that the ADF is to be used, the process proceeds to S320, where the page order of the original document set in the previous S300 is displayed, and in S330, the Start key provided on the operation panel 5 is operated. Wait until

  When the Start key is operated, in S340, the ADF is activated, the image data is read from one original conveyed to the original reading position by the ADF, the read image data is compressed, and the buffer area is compressed. To store.

  In subsequent S350, the image data is read from the original in the order of the original pages set in S300, and all (up to four pages) of image data to be printed on the same sheet are arranged on the buffer area ( If there is no printable data, the process returns to S340 and repeats reading of the image data. On the other hand, if there is printable data, the process proceeds to S360, printing of the printable data is executed, the buffer area in which the printable data is stored is released, and the process proceeds to S370.

  In S370, it is determined whether or not printing of one book (N sheets) has been completed. If printing has not been completed, the process returns to S340 to repeat the processing of S340 to S370, and if printing has been completed, The process ends.

  If it is determined in step S310 that the ADF is not used, the process proceeds to step S380, and the page of the document to be read next by the image forming unit 4 in the page order of the document set in step S300. Is displayed for one page.

  In continuing S390, it waits until the Start key provided in the operation panel 5 is operated. When the Start key is operated, in S400, the image data is read from one original placed at the original reading position by the user, and the read image data is compressed and stored in the buffer area.

  In subsequent S410, it is determined whether there is printable data on the buffer area, assuming that image data is read from the original in the page order of the original set in S300. If there is no printable data, the process returns to S380. Then, after the processing of S380 to S410, that is, the display of the page of the original to be read next is updated, the reading of the original is repeated after the Start key is operated. On the other hand, if there is printable data, the process proceeds to S420, the printable data is printed, the buffer area where the printable data is stored is released, and the process proceeds to S430.

  In S430, it is determined whether or not printing of one book (N sheets) has been completed. If printing has not been completed, the process returns to S380, and the processing of S380 to S430 is repeated. The process ends.

  That is, in this process, according to the determined page layout, the page order of the originals arranged so that the originals to be printed on the same sheet are continuous is notified, and image data is acquired in the notified page order of the originals. As an example, printing is executed from a set of image data to be printed on the same sheet (printable data). Further, when using the ADF for reading the original, it is desirable to rearrange all the originals before starting the reading. Therefore, when the page order of the originals is displayed at a time and the ADF is not used, the user can Since the original is set page by page, only the next read page is displayed.

In the present process is a process as an example of S 380 is updating means.
<Automatic document order printing>
Next, details of the document order automatic setting printing process executed in S200 will be described with reference to the flowchart shown in FIG.

When this processing is started, as shown in FIG. 4, first, in S510, as in the previous S310, it is determined whether or not the ADF is used when the image reading unit 4 reads the document.
If it is determined in S510 that the ADF is to be used, the process proceeds to S520 and waits until the Start key is operated.

  When the Start key is operated, in S530, the free space for storing the compressed image data for one page (assuming the maximum value composed only of images) in the buffer area of the RAM 13 If there is free space, the process proceeds to S540.

  In S540, the ADF is activated, the image data is read from one original conveyed by the ADF to the original reading position, and the read image data is compressed and stored in the buffer area.

  In subsequent S550, it is determined whether or not all (up to four pages) image data to be printed on the same sheet is present in the buffer area (printable data). If there is no printable data, Returning to S530, reading of image data is repeated as long as there is free space. On the other hand, if there is printable data, the process proceeds to S560, where the printable data is printed, the buffer area in which the printable data is stored is released, and the process proceeds to S570.

  In S570, it is determined whether or not printing for one book (N sheets) has been completed. If printing for one book has not been completed, the process returns to S530 and the processes in S530 to S570 are repeated to print one book. If the process is finished, this process is finished.

  If it is determined in the previous S510 that the ADF is not used, the process proceeds to S580, and only the compressed image data for one page is stored in the buffer area of the RAM 13 as in the previous S520. It is determined whether there is free space. If there is free space, the process proceeds to S590.

  In S590, the process waits until the Start key provided on the operation panel 5 is operated. When the Start key is operated, the process proceeds to S600, and the image data from one document placed at the document reading position by the user is displayed. , And the read image data is compressed and stored in the buffer area.

  In subsequent S610, it is determined whether there is printable data in the buffer area. If there is no printable data, the process returns to S580, and the process of S580-S610, that is, the free space for storing the read image data is set. If there is free space, the process of reading the document is repeated after the Start key is operated. On the other hand, if there is printable data, the process proceeds to S620, printing of the printable data is executed, the buffer area in which the printable data is stored is released, and the process proceeds to S630.

  In S630, it is determined whether or not printing for one book (N sheets) has been completed. If printing has not been completed, the process returns to S580 to repeat the processing from S580 to S630, and if printing has been completed, The process ends.

  If it is determined in S530 or S580 that the free space is insufficient, the process proceeds to S640, where the user displays a warning message for notifying that effect and whether to continue or cancel booklet printing. Display to let you select.

In subsequent S650, it is determined whether the selection input by the user via the operation panel 5 is “continue” or “cancel”, and if it is “cancel”, this processing is terminated as it is.
On the other hand, if the selection input is “continue”, the process proceeds to S660, and the compressed image data for two pages (assuming the maximum value composed only of images) can be newly stored in the buffer area. Then, the image data already stored is deleted as much as necessary, and the process proceeds to S670.

  In S670, the page layout is set for the remaining image data (original) that has not been printed, and in subsequent S680, the original order manual setting process described above is executed, and the process is terminated.

  However, in the document order manual setting process started in S680, in S300, the page order is set only for an unread document according to the page layout set in S670. Further, the document corresponding to the image data deleted in S660 is processed as being unread.

  That is, in this process, it is assumed that the image data is acquired in the order of the pages of the document, the document is read, and image data for the print start page number (2N + 2 in this embodiment) is stored in the buffer area. It is supposed to perform printing.

  When the read image data reaches the print start page number and there is not enough free space to store the image data (the memory is insufficient), the fact is notified and printing is stopped. Thus, the user is allowed to select whether to continue the printing by switching to the original order manual setting printing.

In this process, S530 is an example of a switching unit.
<Effect>
As described above, in the image forming apparatus 1 according to the present embodiment, when the original order manual setting printing is executed, according to the determined page layout, the originals arranged so that the originals to be printed on the same sheet are continuously arranged. Assuming that the page order is notified and the image data is acquired in the notified page order, printing is performed from a set of image data to be printed on the same sheet (printable data).

  Therefore, according to the image forming apparatus 1 of the present embodiment, even if there is not enough space in the buffer area to store the image data for the print start page number SP, all of the data to be printed on one sheet (four pages). Booklet printing can be executed if there is enough capacity to store the image data.

  At this time, the user only has to read the document in accordance with the notified page order, and it is not necessary to worry about the rearrangement of the document. As a result, booklet printing can be performed easily.

  Furthermore, according to the image forming apparatus 1 of the present embodiment, when the ADF is used, the page order of the originals is collectively displayed, and when the ADF is not used, only the next reading page is displayed. Since notification suitable for the form is performed, usability can be further improved.

  Further, in the image forming apparatus 1 of the present embodiment, when the number of documents P may not be able to store image data for the print start page number SP depending on the size of one page of image data to be captured. Displays a warning to that effect and determines whether to execute the manual order manual setting print process for manually rearranging the originals or the automatic original order print process for automatically rearranging the originals. And letting the user choose. Further, even when the document order automatic setting printing process is selected, when the buffer area becomes insufficient during reading of the document (image data), it is possible to switch to the document order manual setting printing process at that time. Has been.

Therefore, according to the image forming apparatus 1 of the present embodiment, booklet printing can be executed without bothering the user as much as possible.
[Other Embodiments]
As mentioned above, although several embodiment of this invention was described, this invention is not limited to the said embodiment, In the range which does not deviate from the summary of this invention, it is possible to implement in various aspects. .

  For example, in the above-described embodiment, the acquired image data is compressed and stored in the buffer area. However, the acquired image data may be stored uncompressed. In this case, since the image data of each page has the same data amount, whether or not booklet printing can be executed can be accurately determined based on the total number of pages P. It can be simplified further.

  In the above-described embodiment, when there is a possibility of memory shortage, the configuration is such that the user selects the document order manual setting printing process and the document order automatic setting printing process, but it is determined that the memory shortage is certain. If possible, the original order manual setting printing process may be executed immediately without causing the user to select.

  In the above embodiment, it is determined that there is not enough space to store image data for one page in S530 and S580 of the document order automatic setting print processing, but the free space is sufficient for two pages. When there is only a capacity for storing the image data, when there are three or more unread documents remaining, it may be determined that the available capacity is insufficient. In this case, the process of erasing a part of the already read image data and securing the free capacity for two pages (S660) can be omitted, and the process can be simplified.

  In the above-described embodiment, the case where the image forming unit 3 can perform double-sided printing has been described. However, the image forming unit 3 may perform only single-sided printing. In this case, it is desirable to perform a notification (guidance) instructing to turn the paper over when printing on one side is completed. Further, the notification may be performed every time when single-sided printing of one sheet is completed or when single-sided printing for the total number of printed sheets N is completed. These can be easily dealt with by changing the page order of the original in S300 according to each situation.

  In the above-described embodiment, the notification is performed by displaying the arrangement order of the documents on the operation panel 5, but the notification may be performed by voice guidance.

1 is a block diagram showing the overall configuration of an image forming apparatus to which the present invention is applied. The flowchart which shows the content of the booklet printing process which CPU performs. 6 is a flowchart illustrating detailed contents of a document order manual setting printing process. 6 is a flowchart showing detailed contents of a document order automatic setting printing process. FIG. 3 is an explanatory diagram illustrating a relationship between a page of a document and a reading order. Explanatory drawing showing a page layout.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 3 ... Image forming part 4 ... Image reading part 5 ... Operation panel 6 ... Network I / F 7 ... Facsimile communication part 8 ... External memory card I / F 10 ... Control part 11 ... CPU 12 ... ROM 13 ... RAM 14 ... EEPROM 15 ... I / O control unit

Claims (8)

Page number acquisition means for acquiring the total number of pages of image data;
Image acquisition means for acquiring the image data;
Storage means for storing image data acquired by the image acquisition means;
Printing means for printing the image data stored in the storage means;
The page number acquisition means acquires the page layout for booklet printing, which is executed to create a booklet that is formed by stacking two sheets of paper printed on two pages on the front and back, respectively, and folding it into two. Determining means for determining based on the total number of pages made;
According to the page layout determined by the determining means , the image data notifies the page order to be acquired by the image acquiring means so that the image data to be printed on the same sheet is continuous , and the notified page order a first control means to execute printing as the image data is acquired, the printing unit in order of the image data to be printed on the same sheet is aligned in said storage means by said image acquiring means,
Assuming that the image data is acquired by the image acquisition unit in the order of the pages of the document, when 2N + 2 pages of image data (where N is the number of prints calculated from the total number of pages) is stored in the storage unit, Second control means for causing the printing means to execute booklet printing;
Calculating means for obtaining a free capacity of the storage means and calculating the number of pages that can be stored in the free capacity;
When the number of pages calculated by the calculation means is less than 2N + 2 pages, the control by the first control means is started, and when the number of pages calculated by the calculation means is 2N + 2 or more, Starting means for starting control by the second control means;
An image forming apparatus comprising:   2. The image forming apparatus according to claim 1, wherein the page order of the image data notified by the first control unit is set so that image data to be printed on the same surface of the same sheet is continuous. .   The image forming apparatus according to claim 1, further comprising an update unit that updates notification contents every time image data is acquired by the image acquisition unit. 3. The image forming apparatus according to claim 1, wherein the first control unit collectively reports a page order of the image data to be acquired by the image acquisition unit for a plurality of pages. . The starting means is
When the number of pages calculated by the calculation means is less than 2N + 2 pages, there is provided selection means for allowing the user to select whether to start control by the first control means or control by the second control means. The image forming apparatus according to claim 1 , wherein the image forming apparatus is an image forming apparatus. During the execution of the control by the second control means, when the free capacity of the storage means falls below a predetermined capacity, the number of pages of image data already stored in the storage means and the free capacity of the storage means are stored. sum of the number of pages of the image data which can be, if it is less than 2N + 2 pages, according to any one of claims 1 to 5, characterized in that it comprises a switching means for switching the control by the first control means Image forming apparatus. The image forming apparatus according to claim 6 , wherein the predetermined capacity is large enough to store image data for at least two pages. When the switching means switches to control by the first control means, the first control means notifies the page order to be acquired by the image acquisition means only for unread image data. The image forming apparatus according to claim 6 or 7 .

Images