JP4254033B2 - Image data control apparatus, image forming apparatus, image data control method, and image forming method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention converts print data represented by a page description language (PDL) or the like representing an image to be formed into image data represented by a bitmap or the like, and sends the image data to an image forming unit provided in the image forming apparatus. The present invention relates to an image data control apparatus that controls processing to be performed, and an image forming apparatus including the image data control apparatus.
[0002]
[Prior art]
In recent years, image forming systems in which an image forming apparatus such as a digital copying machine or a printer is connected to a network such as a LAN, and the image forming apparatus is shared by a plurality of terminal devices such as a personal computer (PC) have been widely put into practical use. Yes.
When the image forming apparatus is connected to the network in this way, when data representing an image is transferred from the terminal apparatus to the image forming apparatus, if the data is transferred in the form of already developed image data such as a bitmap, the amount of data to be transferred is It becomes enormous and causes a decrease in network utilization efficiency. Accordingly, for example, the data is transferred in the form of data representing an image (hereinafter referred to as “print data”) expressed in a language called a page description language (PDL), and developed into image data on the image forming apparatus side. It is common.
[0003]
On the other hand, many recent image forming apparatuses have a so-called electronic sort function. Here, the electronic sort function refers to a function for forming a plurality of images for each part, instead of forming a plurality of images for each image when a plurality of images are formed. Therefore, when using the electronic sort function, for example, when a plurality of copies are instructed from the terminal device, even if the image formation for the first part is completed, the image for the second and subsequent copies is formed. Usually, print data or image data (hereinafter referred to as “image data” together) is stored on the image forming apparatus side.
[0004]
[Problems to be solved by the invention]
By the way, when storing image data on the image forming apparatus side, it becomes a problem whether the image data is stored in the form of print data or in the form of already developed image data. However, from the viewpoint of productivity in that image formation is performed more quickly, it can be easily imagined that it is ideal to hold all image data in the form of image data. This is because it is not necessary to develop the image data again at the time of image formation for the second and subsequent copies, and it is possible to perform image formation without interruption.
[0005]
However, since image data is usually much larger than print data, it is necessary to increase the capacity of storage means such as image memory in order to retain all image data in the form of image data. From the viewpoint of cost reduction of the image forming apparatus.
On the other hand, it is conceivable to store all the image data in the form of print data in order to reduce the capacity of the storage means, but in that case, the productivity of image formation may be reduced. In other words, there are images that require a relatively long time to develop into image data, and print data that has a long time to develop although the previous image formation has already been completed. This is because there may occur a case where image formation cannot be performed on the image data until the development is completed.
[0006]
  The present invention has been made in view of the above problems, and is an image data control apparatus capable of preventing image formation productivity deterioration while suppressing an increase in the capacity of a storage unit.,Image forming apparatus, Image data control method, and image forming methodThe purpose is to provide.
[0007]
[Means for Solving the Problems]
  In order to achieve the above object, an image data control apparatus according to the present invention converts data in a first format representing an image to be formed into data in a second format, and an image forming unit provided in the image forming apparatus. In the image data control apparatus for controlling the processing to be sent to the image data, conversion means for converting the data in the first format into the data in the second format for M (M> 1) images, Sending means for sending data in the second format to the image forming unit, first time measuring means for measuring the first time required for conversion by the converting means for each image, and conversion by the converting means Second time acquisition means for acquiring a second time relating to subsequent image formation, storage means for storing data representing the M images, and N portions (N> 1) of the M images are formed. , N-th (1 ≦ n <N) images Determination means for determining for each image whether or not to store the data of the second format when storing the data representing the image in the storage means even after the generation is completed, The decision means isFrom the sum of the second times up to the (m-1) th image, the first time for the images determined not to be stored in the second format among the images up to the (m-1) th image. It is determined whether or not the first time for the mth image is greater than the value obtained by subtracting the sum, and if so, the mth image is stored in the second format, otherwise Decide not to store the mth image in the second formatIt is characterized by.
[0008]
In this configuration, when the image data is stored in the storage unit in preparation for the image formation of the (n + 1) th copy, whether or not the second format data after conversion is stored for the mth image is determined. It was obtained by referring to at least a part of the time required for the conversion of the images up to the (m-1) th sheet, the time related to the image formation after conversion, and the determination result for the images up to the (m-1) th sheet The time is determined based on a result of comparing the time required for converting the m-th image.
[0009]
As will be described later, various specific determination methods are conceivable. However, if the determination is made as described above, the data of the second format is not stored for all images at least in all cases. A decision that can suppress the increase and prevent the occurrence of idle time (non-operation time) of the image forming unit due to the delay in the conversion of the image data of the next page rather than the image formation of one page. Therefore, it is possible to prevent deterioration in productivity of image formation.
[0010]
Here, as the “second time relating to image formation”, various times can be applied in combination with the configuration of the image data control device or the image forming device, and the time is not particularly limited. . To give a specific example, a buffer memory for storing the converted data for the page from the end timing of conversion of the image data corresponding to one page (hereinafter referred to as “when conversion is completed”). From the end of conversion until the end of the operation of the semiconductor laser for the relevant page if it is equipped with a so-called electrophotographic image forming unit. Time is considered. Note that it is not always necessary to actually measure the second time, and a value stored in advance may be acquired based on the paper size, resolution, monochrome / color, or the like. In the case of a device, there may be a case where a fixed value is acceptable (referring to a fixed value is included in “acquisition”).
[0013]
This method is based on the idea that the free time does not occur when the converting means continuously converts the image data not stored in the second format sequentially, so that the free time does not occur. This is a method that is considered to determine that the second image is not stored for a relatively large number of images, and can be said to be a method emphasizing the suppression of the increase in the capacity of the storage means.
[0014]
In order to achieve the above object, an image data control apparatus according to the present invention converts data in a first format representing an image to be formed into data in a second format, and provides an image provided in the image forming apparatus. In the image data control apparatus that controls processing to be sent to the forming unit, conversion means for converting the first format data into the second format data for M (M> 1) images, and conversion A sending means for sending the data in the second format to the image forming unit, a first time measuring means for measuring the first time required for the conversion by the converting means for each image, and the converting means. Second time acquisition means for acquiring a second time relating to image formation after conversion, storage means for storing data representing the M images, and forming N parts (N> 1) of the M images N part (1 ≦ n <N) Determining means for determining for each image whether or not to store the data of the second format when storing data representing the image in the storage means even after image formation is completed, The determination means isIf it is determined not to store the (m-1) th image in the second format, it is determined to store the mth image in the second format, and the (m-1) th image is stored in the second format. If it is determined that the image is to be stored, after searching for the most recent image before the m−1th image in which the second format data is not stored, m is determined from the next image after the searched image. It is determined whether or not the first time for the m-th image is larger than the sum of the second times up to the −1st image. And decide not to store the mth image in the second format otherwiseIt is characterized by.
[0015]
This method is effective for minimizing the capacity of the buffer memory particularly when the sending means has a buffer memory for storing the second format data after conversion. That is, if it is determined not to store the (m−1) th image in the second format, the m−1th image is also converted during the next image formation and stored in the buffer memory. If the m-th image is still stored in the buffer memory when the data conversion is performed without storing the second format data, the m-th image is still stored in the buffer memory. However, in some cases, the storage of the m-th image in the buffer memory may be started, so that it becomes necessary to mount a buffer memory capable of storing a plurality of images.
[0016]
In addition, it is preferable to predetermine in which format the first image is stored, and in consideration of the productivity of image formation, it is usually preferable to store in the second format. Although it is thought that there are many, it is not necessarily limited to it. Further, even when not determined in advance, for example, a determination method of holding in the first format when the time required for conversion of the first image is shorter than a predetermined time is also conceivable.
  Although details will be described later, according to the above method, when the (m−1) th image is present in the buffer memory, control is performed so that the data of the mth image is not converted. Therefore, even if the capacity of the buffer memory is minimized, it is possible to prevent the image formation productivity from being deteriorated. In the case where the buffer memory is provided, in particular, the second time acquisition unit calculates the time from the end of the conversion by the conversion unit to the end of the transmission of the second format data from the buffer memory. It is preferable to acquire as the second time. This is because it is considered suitable for preventing the occurrence of the idle time, but the present invention is not limited to this as described above.
[0017]
In the case where the data amount of the second format is larger than the data amount of the first format, the effect of suppressing the increase in the capacity of the storage means according to the present invention is particularly large. Specifically, The conversion means generally uses a form in which data expressed in a page description language as data in the first format is converted into data expressed in a bitmap as data in the second format. However, the present invention is not limited to this. For example, the present invention is applicable to a case where data in the first format is compressed and data in the second format is decompressed. Is possible.
[0018]
Generally, n = 1, that is, referring to the first time measured at the time of image formation of the first copy, the data stored for image formation of the second copy and thereafter It may be preferable to determine the format, but is not limited to this. In addition, it is preferable that the determination unit further includes a deletion unit that deletes data in the first format from the storage unit for an image determined to be stored in the second format. This is to increase the effect of suppressing the increase in the capacity of the storage means.
[0019]
The image forming apparatus according to the present invention also forms the M sheets after forming the n (1 ≦ n <N) images so as to form the N (N> 1) M (M> 1) images. In an image forming apparatus having a storage unit capable of storing data corresponding to an image, the format of data stored in the storage unit is determined using the above-described image data control device according to the present invention. It is said.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of an image data control apparatus and an image forming apparatus including the image data control apparatus according to the present invention will be described below with reference to the drawings.
(Embodiment 1)
(1) Overall configuration of image forming system
First, an image forming system including an image forming apparatus equipped with the image data control apparatus of the present embodiment will be described. FIG. 1 is a block diagram showing the overall configuration of the image forming system.
[0021]
As shown in the figure, the image forming system is a digital copier (hereinafter simply referred to as “copier”) that forms an image based on image data generated by reading a document or data transferred from the outside. 100) PC or the like on which software (hereinafter referred to as “printer driver”) for converting image data corresponding to a document created and edited using an application such as a word processor or drawing software into the print data is installed. Terminal device 200 and print server 300 that once spools the print data transferred from terminal device 200 via network 500 such as a LAN, and sequentially transfers the data to copying machine 100. For example, PostScript (registered trademark of Adobe Systems Incorporated) can be used as a print data expression method.
[0022]
Further, in the figure, only one copier 100 as an image forming apparatus and only one terminal device 200 are shown. However, these can be connected to a plurality of units, or a telephone line or the like. It is also possible to connect to an external device via
Document image data such as a document created and edited by an application installed in the terminal device 200 is converted into print data of a predetermined format such as the PDL by the printer driver and transferred to the print server 300. The print data transferred to the print server 300 is once spooled in a storage device such as an HDD (hard disk drive) or a RAM provided in the print server 300, and sequentially sent to the copying machine 100 for image formation. The
[0023]
(2) Configuration of the copying machine 100
Next, the configuration of the copying machine 100 according to the present embodiment will be described. FIG. 2 is a schematic cross-sectional view showing the overall configuration of the copying machine 100. As shown in the figure, the copying machine 100 includes an automatic document feeder (hereinafter referred to as “ADF”) 10, a document reading unit 30, a network management unit 40, an image forming unit 50, and a paper feeding unit 70. Yes.
[0024]
The ADF 10 is a device that automatically conveys a document to the document reading unit 30. In other words, the document placed on the document tray 11 is transported to the document reading position on the platen glass 31 by the transport belt 12. The document transported to the document reading position is scanned by the scanner 32 provided in the document reading unit 30 and then is again sent to the right in the drawing by the transport belt 12 and is discharged onto the document discharge tray 13. .
[0025]
The original reading unit 30 optically reads an image of the original conveyed to the original reading position on the platen glass 31, and includes the scanner 32, the CCD sensor 38, the scanner motor M2, and the like.
The scanner 32 is provided with an exposure lamp 33 and a mirror 34 for changing the optical path of light reflected from the original by irradiation of the exposure lamp 33 in a direction parallel to the platen glass 31, and the arrow a in the figure is driven by the scanner motor M2. The original on the platen glass 31 is scanned by moving in the direction. The reflected light from the original is reflected by the mirror 34 and then guided to the CCD sensor 38 via the mirrors 35 and 36 and the condenser lens 37, where it is converted into an electrical signal to generate image data.
[0026]
The generated image data is A / D converted by the image processing unit 39 to become a digital signal, further subjected to known image processing such as shading correction and density conversion processing, and then stored in the memory unit 45. . The image data stored in the memory unit 45 generates a drive signal of a laser diode (hereinafter referred to as “LD”) 51 described later via the print processing unit 46, and forms an image based on the drive signal. An image is formed by the unit 50.
[0027]
The network management unit 40 includes a print data receiving unit 41 that receives the print data transferred from the print server 300 via the network 500, and an image data control unit that develops the print data into image data such as a bitmap. 42 is included. The image data developed by the image data control unit 42 is sent to the print processing unit 46 and used for image formation.
[0028]
The image forming unit 50 forms an image on a recording sheet by a known electrophotographic method. As described above, the print processing unit 46 generates a drive signal for the LD 51 based on the image data stored in the memory unit 45 and the image data sent from the image data control unit 42, and based on the drive signal. Then, the LD 51 is driven to emit laser light. The laser light is reflected by the mirror surface on the side of the polygon mirror 52 that rotates at a predetermined angular velocity, and exposes the surface of the photosensitive drum 56 that is driven to rotate in the direction of arrow b via the fθ lens 53 and the mirrors 54 and 55. Scan.
[0029]
A cleaning unit 57, an eraser lamp (not shown), a charging charger 58, and a developing device 59 are provided around the photosensitive drum 56, and detailed description of these operations is omitted. The paper feed unit 70 is provided with two cassettes 71 and 72, and a recording sheet having a required size is stored in either one of the cassettes 71 and 72 in synchronization with the exposure and development operations of the photosensitive drum 56. Paper is fed from. The fed recording sheet is conveyed below the photosensitive drum 56, and the toner image formed on the surface of the photosensitive drum 56 is transferred to the surface of the recording sheet.
[0030]
Thereafter, the recording sheet is separated from the surface of the photosensitive drum 56 and conveyed to the fixing unit 63 by the conveying belt 62. In the fixing unit 63, the toner image transferred on the surface of the recording sheet is fixed, and the recording sheet after fixing is discharged onto the paper discharge tray 66. Note that the paper conveyance and the driving of the photosensitive drum 56 as described above are controlled by the main motor M1.
[0031]
The copying machine 100 according to the present embodiment applies to a plurality of images based on a series of a plurality of documents read by the document reading unit 30 and a plurality of pages of documents transmitted via the network 500. A so-called electronic sort function is provided that can form a plurality of corresponding images for each part.
When this electronic sort function is used, since image formation is performed again for an image that has once been formed, image data is usually stored in the image forming apparatus. The gist of the present invention is to determine whether print data such as PDL transmitted via the PDL is stored in a format such as PDL or in a format of image data after development by a novel method. That is, by determining the format of data stored by the method of the present invention, an increase in the capacity of storage means such as a memory is suppressed, and deterioration in image formation productivity is prevented.
[0032]
(3) Configuration of the image data control unit 42
Next, the detailed configuration of the image data control unit 42 which forms the gist of the present invention will be described. FIG. 3 is a functional block diagram showing a configuration of the image data control unit 42 of the present embodiment. The image data control unit 42 includes a print data memory 421, a data development control unit 422, and a buffer memory 423.
[0033]
In the print data memory 421, the print data received by the print data receiving unit 41 and once developed by the data development control unit 422 are stored in the form of image data, for example, in order to form a plurality of images thereafter. Data is stored. Specifically, various RAMs and HDDs can be used. In the figure, for convenience of explanation, the print data area 421a and the image data area 421b are shown separated by a dotted line, but physically, both types of data may be mixed. Hereinafter, the print data of the mth image may be represented by Pm, and the image data of the mth image may be represented by Mm. The same applies to FIG.
[0034]
The data development control unit 422 controls the development from the print data Pm to the image data Mm and the storage of the image data in the buffer memory 423 provided in the middle of the print processing unit 46. FIG. 4 is a diagram showing details of the configuration of the data development control unit 422. The data development control unit 422 includes a data development unit 501, a development time measurement unit 502, a transmission time measurement unit 503, a storage format determination unit 504, and an image data deletion unit 505.
[0035]
The data expansion unit 501 expands print data into image data for each page and stores the image data in the buffer memory 423, and also temporarily stores the image data in the print data memory 421. The development time measurement unit 502 measures the time required for the development of the print data by the data development unit 501 for each image and sends it to the storage format determination unit 504. The time measured by the deployment time measuring unit 502 is hereinafter referred to as “deployment time”.
[0036]
The sending time measuring unit 503 measures the time required for sending data from the buffer memory 423 to the print processing unit 46 for each image after the data developing unit 501 finishes developing. The time measured by the sending time measuring unit 503 is hereinafter referred to as “sending time”. The sending time is also sent to the storage format determination unit 504 in the same manner as the development time.
[0037]
The storage format determination unit 504 is configured to use a storage unit (not shown) that temporarily stores the development time and the transmission time measured for a plurality of images, and is based on the information on the two types of time. Thus, it is determined whether the print data is stored in the print data memory 421 in the print data format or the image data format. This determination method will be described in detail later. The data stored in the print data memory 421 is used to form an image on which image formation has already been performed. Specifically, for example, in the case of image formation for the second and subsequent copies when performing image formation of a plurality of copies, for example. Used for. In this case, the image stored in the print data format is expanded and used again by the data expansion unit 501 when the image is formed again, but the image stored in the image data format is used as it is. It can be used for image formation again, so that development time is not required. In the figure, the path for directly transferring the image data to the print processing unit 46 without passing through the buffer memory 423 is not shown.
[0038]
The image data deletion unit 505 stores, in the print data memory, the image data for the image determined to be stored in the print data format by the storage format determination unit 504 and the print data for the image determined to be stored in the image data format. Delete from 421. Thereby, for example, as shown in FIG. 3, there is no duplication of images stored in the print data memory 421. However, since it is normal that the capacity required for storing the print data is small compared with the image data, the print data may be stored for all the images.
[0039]
(4) Processing contents in the image data control unit 42
Next, details of specific processing contents performed by the image data control unit 42 will be described. It should be noted that, as a specific process of the image data control unit 42, the development time and the sending time are measured when the n-th image (the first image in the present embodiment) is formed, and the results are obtained. Based on the above, a process for controlling whether image data is stored in the print data format or image data format in preparation for subsequent image formation (second and subsequent copies in the present embodiment) Therefore, the following description will be focused on the storage format determination process.
[0040]
FIG. 5 is a flowchart showing the contents of the storage format determination process in the present embodiment. In this process, for example, for the mth image (m> 1), the development from the print data to the image data is completed, and the image data for the m−1th image is printed from the buffer memory 423. This can be done after everything is sent to the unit 46. This is because the measurement of the development time Cm for the mth image and the transmission time T (m-1) for the m-1st image ends. Note that it is preferable to determine a storage method for the first image in advance. Considering the productivity of the second and subsequent copies, it is usually preferable to store in the image data format, but it may be stored in the print data format, and the development time C1 of the first image is A method of saving the image data in the form of image data when the value is larger than a predetermined value is also conceivable.
[0041]
In the storage format determination process, first, the sum ΣT (m−1) of transmission times for the images up to the (m−1) th image is calculated (S101). The calculated value is hereinafter referred to as “total transmission time. Next, for the images up to the (m−1) th image, the total development time for the images determined to be stored in the print data format is calculated (S102). In the figure, for the sake of convenience, it is expressed as ΣC (m−1), but for images stored in the image data format, the expansion time for the second and subsequent copies does not occur, so the total expansion time ( Hereinafter, it is excluded from “total deployment time”). Hereinafter, for the images up to the (m−1) th image, the total transmission time calculated as described above is simply expressed as ΣT, and the total development time is simply expressed as ΣC.
[0042]
Next, it is determined whether or not the expansion time Cm for the m-th image is greater than the difference between the total transmission time ΣT and the total expansion time ΣC (S103). As a result of this determination, it is determined whether the m-th image data is stored in the print data format or the image data format. The meaning of this determination will be described in detail below.
[0043]
FIG. 6 is a timing chart for explaining the determination method of the present embodiment. In the figure, the development of the first image has been completed by timing A, and the first image from timing A is sent from the buffer memory 423 to the print processing unit 46 (hereinafter simply referred to as “sending”). ) Has been started. In this embodiment, a buffer memory 423 having a capacity capable of storing a plurality of images is used, and at the same time as the transmission of the first image starts, the print data of the second image is developed. It is also assumed that storage into the buffer memory 423 can be started.
[0044]
In the example shown in the figure, since the transmission time T1 of the first image is longer than the development time C2 of the second image, the second image is sent at a timing earlier than the completion of the transmission of the first image. Deployment ends. Therefore, as soon as the transmission of the first image is completed, the transmission of the second image can be started. In this case, since the productivity of image formation does not deteriorate even if the second image is not stored in the image data format, it is determined that the second image is stored in the print data format.
[0045]
On the other hand, in the example shown in the figure, since the expansion time C3 of the third image is long, the transmission of the third image cannot be started immediately even after the transmission of the second image is completed. Free time will occur before the start of transmission of the third image. Since this idle time means deterioration in productivity of image formation, in such a case, it is preferable to store the third image in the form of image data.
[0046]
Such a determination is performed in the comparison process in step S103. That is, the development time Cm of the m-th image is the time obtained by subtracting the total of the development time generated up to the m-1st sheet from the total of the transmission times of the images up to the m-1st sheet (in FIG. Is longer than the timing B to the timing C), the m-th image is stored in the image data format. As shown in FIG. 6, if the expansion process of the m-th image is completed earlier than the completion of the transmission of the (m-1) -th image or is completed at the same time, the space until the transmission of the m-th image is started. This is because time does not occur. Note that it is preferable to determine in advance in which format the first image is stored. In the present embodiment, the image formation is emphasized with emphasis on productivity of image formation. The data is saved in the format.
[0047]
Returning to the flowchart of FIG. 5, if Cm is larger than ΣT−ΣC as a result of the above determination (S103: Yes), the mth image data is stored in the image data as image data. The print data of the image is deleted (S104). In the opposite case, the image data of the mth image is deleted (S105). As described above, the print data may be saved by omitting step S104.
[0048]
As described above, by performing the image data control according to the present embodiment, the image data can be stored in the print data format as much as possible, so that an increase in the capacity of the print data memory 421 is suppressed. When the deterioration of productivity is caused, it is stored in the form of image data, so that the deterioration of productivity can be prevented.
Depending on the amount of images to be stored, for example, when the amount of images to be stored in the image data format increases, there may be a case where the data of all images cannot be stored in the print data memory 421. In such a case, control is performed so that the image data does not occupy a certain amount of capacity. For example, even if it is preferable from the viewpoint of productivity to store the original image data, it is stored in the print data format. It is preferable to perform a process such as.
[0049]
(Embodiment 2)
Next, a second embodiment of the present invention will be described. As described above, in the first embodiment, it is determined whether or not the expansion of the mth image is completed before the transmission of the (m-1) th image is completed. The method of saving in the format of was used. In this method, print data can be stored as much as possible within a range where productivity is not reduced. Therefore, this method is effective in suppressing an increase in the capacity of the print data memory 421. On the other hand, the (m−1) th image is effective. Since the image data of the mth image may be stored in the buffer memory 423 before the transmission of the image data is completed, it is necessary to provide the buffer memory 423 that can store a plurality of images.
[0050]
That is, in the example shown in FIG. 7, the second to sixth images are all held in the print data format in the determination by the method of the first embodiment. On the other hand, when the image is formed, when the sixth image is developed, the image data of the fourth and fifth images are already developed and stored in the buffer memory 423. For example, at the timing indicated by D in the figure, it is necessary to secure an area for three images as the capacity of the buffer memory 423. The storage element used as the buffer memory 423 is often more expensive than the print data memory 421, and as a result, the cost of the image forming apparatus can be increased.
[0051]
Therefore, in this embodiment, a method for preventing deterioration in productivity while minimizing the capacity of the buffer memory 423 will be described. FIG. 8 is a flowchart showing the contents of the storage format determination process in the present embodiment. As for the first image, it is preferable to determine the storage format in advance, as in the first embodiment, and it is usually preferable to store in the image data format. In this embodiment, the first image is stored in the image data format.
[0052]
In this embodiment, when determining the storage format of the m-th image, first, the storage format of the (m−1) -th image that is the image immediately before the image is referred to (S201), and the (m−1) -th image is stored. When the eye image is stored in the print data format (S201: Yes), the m-th image is stored in the image data format. Accordingly, the print data is deleted (S205), but the deletion process may be omitted as in the first embodiment.
[0053]
On the other hand, when the (m-1) th image is stored in the image data format, the storage format of the mth image is determined as follows. That is, a search is made for the number of images before the m-th image, which is the image stored as print data (S202). Here, the searched image data is hereinafter referred to as latest print data.
[0054]
Next, the total transmission time ΣT from the image after the most recent print data to the m−1th image is calculated (S203). In this case, all the images to be calculated are stored as image data. Then, the calculated ΣT and the m-th image development time Cm are compared (S204). If Cm is larger (S204: Yes), it is decided to save the image data and the print data is deleted. (S205), otherwise (S204: No), it is decided to save in the format of the print data, and the image data in the print data memory 421 is deleted (S206).
[0055]
As described above, the next image after the image saved in the print data format is saved as image data, and the next image after the image saved in the image data format is determined as described above. The reason for this will be described below. That is, for example, in the example of FIG. 6, if it is determined that the second image is stored in the print data format, the second image is stored in the buffer memory 423 when the third image is also stored in the print data format. Before the image is sent out, the third image is developed and stored in the buffer memory 423, so that it is necessary to secure a capacity for a plurality of images as the capacity of the buffer memory 423.
[0056]
However, if the capacity of the buffer memory 423 is to be minimized, another image should not be developed until the transmission of the image data corresponding to the second image is completed. On the other hand, in this case, if the third image is held as print data, the development of the third image starts from the timing at which the transmission of the image data of the second image is completed, and image formation production is performed. The properties are significantly reduced.
[0057]
Therefore, in this embodiment, the image next to the image stored as print data is stored unconditionally in the form of image data. In this way, in the above example, the formation of the third image can be started immediately after the transmission of the image data corresponding to the second image is completed. This is because it does not cause deterioration.
[0058]
Here, how to determine the fourth image is a problem. The determination is performed in steps S202 to S204 in FIG. This process will be described with reference to FIG. In the example shown in the figure, the second image is stored as print data, and the latest print data is the second image data. Therefore, the transmission time (T3) of the third image is compared with the development time (C4) of the fourth image.
[0059]
As shown in the figure, when C4 is larger than T3, if the fourth image is stored as print data, even if the transmission of the third image data is completed (timing G), the fourth image Image data transmission cannot be started, and image formation productivity deteriorates. This is because the fourth image cannot be sent out until the end timing F of the fourth image development.
[0060]
Therefore, when C4> T3, the fourth image is stored as image data. In other cases, the productivity is not deteriorated even if the fourth image is stored as print data, so the image is stored as print data. In addition, when the fourth sheet data is stored as image data, since the fifth sheet image can be developed from the time when the second sheet data transmission is finished (timing E), The storage format of the fifth image is determined by comparing the development time (C5) of the fifth image with (T3 + T4) (S204).
[0061]
As described above, according to the method of the present embodiment, the capacity of the buffer memory 423 can be minimized without causing deterioration in productivity of image formation. In this case, the number of images stored in the image data format is increased as compared with the method of the first embodiment, but a storage unit having a lower cost than the buffer memory 423 is used as the print data memory 421. When used, it can be said to be particularly effective.
[0062]
<Modification>
Although the embodiments of the present invention have been described above, the contents of the present invention are not limited to the specific examples shown in the above embodiments, and for example, consider the following modifications. Can do.
(1) That is, in the above embodiment, since the case where the image data once expanded when the print data is expanded into the image data is stored in the buffer memory 423 has been described, the sending time measuring unit, after the expansion ends, Although the time until the transmission of data from the buffer memory is completed is measured, the time measured by this transmission time measuring unit may be another time.
[0063]
Specifically, for example, in the case of a laser printer, there may be a method of measuring the time from the completion of the development until the driving of the semiconductor laser corresponding to the image is completed, and the image is formed. It is also possible to measure the time until completion of discharging the recorded sheet.
(2) In the above embodiment, the print data memory 421 is provided separately from the memory unit 45, but these may be physically the same memory. In the above embodiment, the case where the copying machine 100 is used as an example of the image forming apparatus has been described. However, the present invention can be applied to various image forming apparatuses such as a printer and a facsimile machine other than the copying machine. The image forming method is not limited to the electrophotographic method, and can be applied to various image forming methods. Of course, if the image formation method is different, it may be preferable to use a time different from the time until the transmission from the buffer memory is completed as the time related to the image formation expressed as the transmission time in the above embodiment. .
[0064]
(3) In the above embodiment, the sending time is measured for each image by the sending time measuring unit 505. This sending time may be a monochrome image having the same paper size and resolution, for example. In some cases, it is not necessary to actually measure, for example, it is considered that they are almost the same. Therefore, for example, it may be stored in a table or the like in advance for each of the paper size, resolution, monochrome / color, etc., and the stored value may be acquired based on each parameter. In such an apparatus, a fixed value may be used when only monochrome images of the same resolution and the same paper can be formed.
[0065]
【The invention's effect】
As described above, according to the image data control apparatus and the image forming apparatus according to the present invention, it is possible to prevent deterioration in productivity while suppressing an increase in the capacity of the storage unit that stores image data. There is.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an overall configuration of an image forming system.
FIG. 2 is a schematic cross-sectional view showing the overall configuration of the copying machine 100. FIG.
3 is a functional block diagram showing a configuration of an image data control unit 42. FIG.
FIG. 4 is a diagram showing details of the configuration of a data development control unit 422;
FIG. 5 is a flowchart showing the contents of a storage format determination process in the first embodiment.
FIG. 6 is a timing chart for explaining a determination method according to the first embodiment;
FIG. 7 is a timing chart for explaining a determination method according to the first embodiment;
FIG. 8 is a flowchart showing the contents of a storage format determination process in the second embodiment.
FIG. 9 is a timing chart for explaining a determination method according to the second embodiment;
[Explanation of symbols]
10 Automatic document feeder (ADF)
30 Document reading unit
39 Image processing section
40 Network Management Department
41 Print data receiver
42 Image data control unit
45 memory units
46 Print processing section
50 Image forming unit
70 Feeder
100 copier
200 Terminal device
300 Print server
421 Print data storage unit
422 Data development control unit
423 Buffer memory
500 networks
501 Data development department
502 Deployment time measurement unit
503 Sending time measurement unit
504 Save format determination unit
505 Image data deletion unit

Claims (14)

In an image data control device that controls processing of converting data in a first format representing an image to be formed into data in a second format and sending the data to an image forming unit provided in the image forming device.
Conversion means for converting the data of the first format into the data of the second format for M (M> 1) images;
Sending means for sending the converted second format data to the image forming unit;
A first time measuring means for measuring a first time required for conversion by the converting means for each image;
Second time acquisition means for acquiring a second time related to image formation after conversion by the conversion means;
Storage means for storing data representing the M images;
To store the data representing the image in the storage means even after the n-th (1 ≦ n <N) image formation is completed in order to form the M images (N> 1). Determining means for determining for each image whether or not to store the data in the second format,
The determining means includes
From the sum of the second times up to the (m-1) th image, the first time for the images determined not to be stored in the second format among the images up to the (m-1) th image. It is determined whether or not the first time for the mth image is greater than the value obtained by subtracting the sum, and if so, the mth image is stored in the second format, otherwise Is determined not to store the m-th image in the second format . In an image data control device that controls processing of converting data in a first format representing an image to be formed into data in a second format and sending the data to an image forming unit provided in the image forming device.
Conversion means for converting the data of the first format into the data of the second format for M (M> 1) images;
Sending means for sending the converted second format data to the image forming unit;
A first time measuring means for measuring a first time required for conversion by the converting means for each image;
Second time acquisition means for acquiring a second time related to image formation after conversion by the conversion means;
Storage means for storing data representing the M images;
To store the data representing the image in the storage means even after the n-th (1 ≦ n <N) image formation is completed in order to form the M images (N> 1). Determining means for determining for each image whether or not to store the data in the second format,
The determining means includes
If it is determined not to store the (m-1) th image in the second format, it is determined to store the mth image in the second format, and the (m-1) th image is stored in the second format. If it is determined that the image is to be stored, after searching for the most recent image before the m−1th image in which the second format data is not stored, m is determined from the next image after the searched image. It is determined whether or not the first time for the m-th image is larger than the sum of the second times up to the −1st image. The image data control device is characterized in that it is stored so that the mth image is not stored in the second format otherwise . The determining means includes
The image data control apparatus according to claim 1 or 2 , wherein the first image is determined to be stored in a predetermined format. The delivery means includes
A buffer memory for storing the converted second format data;
The second time acquisition means includes
The time from the end of the conversion by the conversion means to the end of the transmission of the data in the second format from the buffer memory is obtained as the second time . The image data control apparatus according to any one of the above. The converting means includes
The data that has been represented in a page description language as the first type of data, any of the preceding claims, characterized in 4 to be converted into data that is represented by a bitmap as a second type of data whether the image data control apparatus according to (1). It said determining means further comprises
The image determined to be stored in the second form, according to any one of claims 1 to 5, characterized in that it comprises a deletion means for deleting the data of the first format from the storage means Image data control device. In order to form N (N> 1) images of M (M> 1), data corresponding to the M images can be stored even after forming n (1 ≦ n <N) images. In an image forming apparatus having possible storage means,
An image forming apparatus using the image data control device according to claim 1 to determine a format of data stored in the storage unit.   An image provided in the image forming apparatus is provided with storage means for storing data representing M (M> 1) images, converting data in the first format representing the image to be formed into data in the second format. An image data control method in an image data control apparatus for controlling processing to be sent to a forming unit,
  A conversion step for converting the data in the first format into the data in the second format for the M images;
  A sending step of sending the converted data in the second format to the image forming unit;
  A first time measurement step of measuring a first time required for conversion by the conversion step for each image;
  A second time acquisition step of acquiring a second time relating to image formation after conversion by the conversion step;
  To store the data representing the image in the storage means even after the nth (1 ≦ n <N) image formation is completed in order to form the M images (N> 1). Determining for each image whether or not to store the data in the second format,
  The determining step includes
  From the sum of the second times up to the (m-1) th image, the first time of the images determined not to be stored in the second format among the images up to the (m-1) th image. It is determined whether or not the first time for the m-th image is larger than the value obtained by subtracting the sum, and if it is larger, the m-th image is stored in the second format, otherwise Decide not to store the mth image in the second format
  An image data control method characterized by the above.   An image provided in the image forming apparatus is provided with storage means for storing data representing M (M> 1) images, converting data in the first format representing the image to be formed into data in the second format. An image data control method in an image data control apparatus for controlling processing to be sent to a forming unit,
  A conversion step for converting the data in the first format into the data in the second format for the M images;
  A sending step of sending the converted data in the second format to the image forming unit;
  A first time measurement step of measuring a first time required for conversion by the conversion step for each image;
  A second time acquisition step of acquiring a second time relating to image formation after conversion by the conversion step;
  To store the data representing the image in the storage means even after the nth (1 ≦ n <N) image formation is completed in order to form the M images (N> 1). Determining for each image whether or not to store the data of the second format,
  The determining step includes
  If it is determined not to store the (m-1) th image in the second format, it is determined to store the mth image in the second format, and the (m-1) th image is stored in the second format. If it is determined that the image is to be stored, after searching for the most recent image before the m−1th image in which the second format data is not stored, m is determined from the next image after the searched image. It is determined whether or not the first time for the m-th image is larger than the sum of the second times up to the −1st image. And decide not to store the mth image in the second format otherwise
  An image data control method characterized by the above.   The determining step includes
  Decide to store the first image in a predetermined format
  10. The image data control method according to claim 8 or 9, wherein:   The image data control device further includes a buffer memory,
  The sending step includes
  Storing the converted second format data in the buffer memory;
  The second time acquisition step includes:
  The time from the end of the conversion in the conversion step to the end of the transmission of the second format data from the buffer memory is acquired as the second time.
  The image data control method according to claim 8, wherein:   The converting step includes
  Converting data expressed in page description language as data in the first format into data expressed in bitmaps as data in the second format
  The image data control method according to claim 8, wherein:   The determining step further comprises:
  For an image determined to be stored in the second format, a deletion substep for deleting data in the first format from the storage means is included.
  The image data control method according to claim 8, wherein:   Storage means capable of storing data corresponding to the M images even after forming n (1 ≦ n <N) images so as to form N (N> 1) M images. An image forming method in an image forming apparatus having:
  A format of data stored in the storage means is determined using the image data control method according to any one of claims 8 to 13.
  An image forming method.

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