JPH10240476A - Printing system, control method for the same and information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing system, control method for the same and information processor with which total throughput can be improved without cost-up in the printing system having a double side printing mechanism. SOLUTION: A processing load predictive part 203a calculates the predictive value of time for processing print data prepared on a host computer 200. Next, based on the calculated predictive value, the double side printing mode of a printer 100 is selected by a double side printing mode discriminating part 203b. Then, based on the selected double side printing mode, the constitution of data stream in print data is changed by a data stream processing part 203c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an information processing apparatus,
The present invention relates to a printing system having a printing apparatus having a duplex printing function capable of performing duplex printing in a plurality of types of duplex printing modes, a control method thereof, and an information processing apparatus.

[0002]

2. Description of the Related Art A method for controlling double-sided printing in a printing system having a conventional double-sided printing mechanism will be described. Here, a form in which the target double-sided printing mechanism allows n sheets of recording paper (cut sheets) to stay in the printing apparatus (a print mode capable of performing double-sided printing in such a form is referred to as an n-page double-sided print mode). The description will be made on the assumption that the printing apparatus has a mechanism (mechanical characteristic) that improves the throughput during double-sided printing depending on the staying form and the printing order (alternate sheet feeding method). Incidentally, the following are already known as those relating to the double-sided printing mechanism having such mechanical characteristics.

[0003] Japanese Patent Application Laid-Open No. 1-170953 Image Forming Apparatus Canon [Patent Document] Japanese Unexamined Patent Application Publication No. 2-289864 Double-sided Image Forming Method Ricoh Generally, in a printing apparatus equipped with such a double-sided printing mechanism or detachable, the following is known. The control method of double-sided printing as described above is used. For example, PCL or LIPS I
V and other page description languages (hereinafter PDL (Printer Descri
ption Language) for printing on both sides of a printing device.
Graphical user interface of a printer driver on a computer (hereinafter, GUI (Graphic User Inter
face)), there is only means for designating whether or not to perform double-sided printing. By the designation, the host
The printer driver on the computer adds a predetermined PDL double-sided printing designation command to the print data to be sent, or instructs the printing apparatus to perform double-sided printing by specifying parameters of the double-sided printing designation command. At this time, regardless of whether or not double-sided printing is specified, the host computer
The print data is sent to the printing apparatus in accordance with the order of pages 2, 3, and 4 from the first page and the order created by an application such as word processing software.

On the other hand, for example, in a printing apparatus corresponding to double-sided printing in a 5-page double-sided printing mode, 1, 2,.
When printing print data consisting of 3, 4, 5, 6, 7,... Pages in two-sided printing, a two-page double-sided printing mode in which printing is performed in the order of 2, 1, 4, 3,. 3,
, A 4-page duplex printing mode for printing in the order of pages 6, 8, 5, 7,..., A 5-page duplex printing mode for printing in the page order of 2, 4, 1, 6, 3, 8, 5, 10,. The three-sided printing mode is dynamically switched to perform the two-sided printing. This switching timing is determined by the state of the page developed in the page memory in the PDL controller before the PDL controller in the printing apparatus outputs the PRNT signal (or PREF signal or paper feed selection signal) to the printer engine. It is decided according to. For example, if the development of the print data for four pages following the print processing of the second page is completed, the output from the third page is switched to the four-page double-sided print mode, and 1, 2, 4, 6, 3 , 5
Are printed in the page order. By dynamically switching the two-sided printing mode in this manner, the time required to obtain the final result for the remaining four pages is reduced as compared with the case of performing the two-sided printing only in the two-page two-sided printing mode.

In the processing on the host computer side, Windows NT and Windows 95 (both are registered trademarks of Microsoft Corporation in the United States) have a function of processing a data stream of print data called a print processor. In this print processor, a data stream of print data created by a system (GDI) or a printer driver is stored in a storage medium, or a stored data stream of print data is output to a system (GDI) or a printing apparatus. Is performed specially.

[0006] Conventionally, an application is a system (G
DI) and a data stream of intermediate print data (for example, EMF in Windows 95)
(= Extended metafile) is output to the printer driver without any processing. Then, the print data is sequentially processed by the printer driver and then output to the printing device. In some cases, it is possible to specify whether to print the print data including a plurality of pages in order from the first page or to print from the last first page. In such a case, basically, in such a case, The printing order of each page is controlled at the level of application software such as a word processor or spreadsheet software, and a printer driver or a print processor does not intervene in such page-by-page processing.

Further, not all application software has a control function of a double-sided printing mechanism, and at present, only a very limited set of software supports the function. The reason for this situation is that the user environment such as a printing apparatus having a double-sided printing mechanism is not sufficiently widespread,
Application to support the control function
Work load on the software maker side can be cited.

[0008]

However, the printing system having the conventional double-sided printing mechanism has the following problems. 1. In order to achieve higher total throughput in a printing apparatus having a current double-sided printing mechanism, it is necessary to secure a storage area in a page memory of the printing apparatus. turn into.

[0009] 2. Switching of the n-page double-sided printing mode is performed only in accordance with the number of pages expanded in the page memory immediately before print data is output.
Waiting for 2 seconds, the development of print data for 4 pages is completed, and printing can be performed in the 4-page double-sided print mode. Even in the case where the printing is shorter than the printing in the page double-sided printing mode, printing is currently performed in the two-page double-sided printing mode. As described above, in order to obtain the optimum total throughput, it is not possible to determine the content of the print data and switch the n-page double-sided printing mode according to the determination result. That is, the mechanical characteristics of the double-sided printing mechanism, which should be used to increase the throughput, cannot be fully utilized.

The present invention has been made in view of the above problems, and in a printing system having a double-sided printing mechanism, a printing system capable of improving the total throughput without increasing the cost, and a control method therefor,
It is an object to provide an information processing device.

[0011]

A printing system according to the present invention for achieving the above object has the following arrangement.
That is, a printing system having an information processing apparatus and a printing apparatus having a double-sided printing function capable of performing double-sided printing in a plurality of types of double-sided printing modes, wherein the processing time of print data created on the information processing apparatus is reduced. Calculating means for calculating the predicted value, based on the predicted value calculated by the calculating means,
Selecting means for selecting a duplex printing mode of the printing apparatus;
Based on the duplex printing mode selected by the selection means,
Changing means for changing the configuration of the data stream of the print data.

Preferably, the apparatus further comprises output means for outputting the data stream changed by the change means to the printing device. Preferably, the print data is configured in page units. Preferably, the page is configured on an object record basis.

Preferably, the calculation means includes a table for managing values corresponding to a plurality of types of object records. Preferably, the calculation unit acquires a value corresponding to an object record constituting a page constituting the print data from the table, and assigns a coefficient indicating a processing capability of the information processing apparatus to the acquired value. The integrated value is calculated as the predicted value.

Preferably, the information processing device and the printing device are locally connected. Preferably, the information processing device and the printing device are connected via a network line. A printing system control method according to the present invention for achieving the above object has the following configuration. That is, a method for controlling a printing system including an information processing apparatus and a printing apparatus having a double-sided printing function capable of performing double-sided printing in a plurality of types of double-sided printing modes. A calculating step of calculating a predicted value of the processing time; a selecting step of selecting a duplex printing mode of the printing apparatus based on the predicted value calculated in the calculating step; and a duplex printing mode selected in the selecting step. Changing the configuration of the data stream of the print data based on the print data.

An information processing apparatus according to the present invention for achieving the above object has the following configuration. That is, an information processing apparatus that outputs print data to a printing apparatus having a double-sided printing function capable of performing double-sided printing in a plurality of types of double-sided printing modes, and a calculating unit that calculates a predicted value of a processing time of the print data Selecting means for selecting a double-sided printing mode of the printing apparatus based on the predicted value calculated by the calculating means; and forming a data stream of the print data based on the double-sided printing mode selected by the selecting means. Changing means for changing.

A computer readable memory according to the present invention for achieving the above object has the following configuration. That is,
A computer-readable memory storing a program code for controlling a printing system having an information processing apparatus and a printing apparatus having a duplex printing function capable of performing duplex printing in a plurality of types of duplex printing modes, wherein the program code is stored on the information processing apparatus. A program code for calculating a predicted value of the processing time of the print data created in the above, and a program code for a selecting step for selecting the duplex printing mode of the printing apparatus based on the predicted value calculated in the calculating step And a program code for a changing step of changing the configuration of the data stream of the print data based on the duplex printing mode selected in the selecting step.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. Before describing the configuration of the present embodiment, a printing apparatus (laser beam printer (hereinafter, “LB”) responsible for printing of a printing system to which the present embodiment is applied.
P))) will be described with reference to FIG. Note that the printing apparatus is not limited to the LBP, and can be applied to a printing apparatus using another recording method such as an ink jet printer or a thermal transfer printer.

FIG. 1 is a sectional view showing a basic configuration of a printing apparatus having a double-sided printing mechanism according to an embodiment of the present invention. In FIG. 1, reference numeral 100 denotes a printing apparatus main body. Printing device 100
Is a host computer 200 connected to the outside.
Print data (character codes, images, etc.) and control codes, or print data, such as job control instructions, supplied from the printer and input them, and create images such as corresponding character patterns and images in accordance with the print data. Then, an image is formed on recording paper as a recording medium. 12
Reference numeral 0 denotes an operation panel on which switches for various operations, an LED display, and the like are arranged. 110 denotes a formatter control unit that controls the printing apparatus 100 and performs a printing process for analyzing print data supplied from the host computer 200. It is. In the formatter control unit 110, the image data is converted into an image signal corresponding to the print data and output to the laser driver 131.

The laser driver 131 is a semiconductor laser 14
The first drive circuit switches on / off a laser beam 142 emitted from the semiconductor laser 141 in accordance with an image signal input from the format control unit 110. The laser beam 142 scans and exposes the electrostatic drum 144 while being swung in the left-right direction by the rotating polygon mirror 143. As a result, an electrostatic latent image such as a character pattern or an image is formed on the electrostatic drum 144. This electrostatic latent image is developed by a developing unit 145 disposed around the electrostatic drum 144 and then transferred to a recording sheet (here, in order to simplify the following description, a laser driver 131 and a semiconductor Laser 141, laser beam 142, rotating polygon mirror 143,
The electrostatic drum 144 and the developing unit 145 are collectively referred to as an image forming unit 14).

A cut sheet S is used as recording paper. The cut sheet S is stored in a detachable paper cassette 146 mounted on the printing apparatus 100. The paper cassette 146 is provided with a paper feed roller 147 for feeding the cut sheet S. In addition, the feed roller 147 and the transport roller pair 1
Downstream of the registration roller pair 14 that conveys the cut sheet S in synchronization with the image formed by the image forming unit 14
9 are provided. And this registration roller pair 1
The image forming unit 14 is provided downstream of 49. Further, a transport belt 150 that transports the cut sheet S is disposed downstream of the image forming unit 14, and a fixing device 151 is disposed downstream of the belt 150.

Downstream of the fixing device 151, a pair of transport rollers 15 is provided.
2, and a flapper 153 is provided downstream of the transport roller pair 152. In addition, the flapper 153
A discharge roller pair 154 is disposed downstream of the printing apparatus 100, and a discharge tray 155 is disposed outside the printing apparatus 100 downstream of the discharge roller pair 154. On the other hand, a front / back inversion path 156 is provided, which is branched into a flapper 153, and a conveyance roller pair 157 and a paper re-feed roller pair 158 are provided in the front / back inversion path 156.

Next, an outline of a printing operation when one-sided printing is performed by the printing apparatus 100 will be described. First, the cut sheet S is fed from the paper feed cassette 146 by the paper feed roller 147 according to the PRNT signal instruction from the formatter control unit 110. The cut sheet S abuts on the registration roller pair 149 to correct skew. Next, the print data from the host computer 200 is converted into an image signal by the formatter control unit 110 and transmitted to the image forming unit 14. Next, the cut sheet S is conveyed to the image forming unit 14 by the registration roller pair 149 in synchronization with the image formed by the image forming unit 14 by the image signal. Then, an image is formed on the cut sheet S by the image forming unit 14. Further, the cut sheet S on which the image is formed is transported by the transport belt 150 to the fixing device 151, and
The image is fixed by 51. And cut sheet S
Is transported to a flapper 153 by a transport roller pair 152 and is discharged onto a paper discharge tray 155 by a paper discharge roller pair 154.

Next, an outline of a printing operation when two-sided printing is performed by the printing apparatus 100 will be described. For duplex printing,
The first cut sheet S1 having an image formed on the surface thereof by the printing operation of the single-sided printing described above is discharged from the discharge tray 15 by the discharge roller pair 154 by the flapper 153.
5 is conveyed to the B position. At this time, when a sensor (not shown) detects that the rear end of the cut sheet S1 has passed the flapper 153, the flapper 153 moves
Switch to 6 side. Next, the sheet discharge roller pair 154 is inverted, and the cut sheet S <b> 1 is transported to the front / back inversion path 156.
Then, the cut sheet S1 is conveyed to the position A by the pair of conveying rollers 157 through the front / back inversion path 156 and stopped.

Subsequently, a second cut sheet S2 is fed from a paper cassette 146 by a paper feed roller 147. Next, the sheet is conveyed to the position B of the discharge tray 155 by the same operation as that of the first cut sheet S1. Next, the cut sheet S1 located at the position A is re-fed by the re-feed roller pair 158 in response to a re-feed signal from the formatter controller 110. Then, the skew is corrected by contacting the pair of registration rollers 149. At this time, the cut sheet S2 located at the position B is placed on the front / back inversion path 1 while maintaining a predetermined distance from the cut sheet S1.
The sheet is conveyed to the position A by the pair of conveying rollers 157 through 56.

An image is also formed on the back surface of the cut sheet S 1 by the above-described single-sided printing operation, and the cut sheet S 1 is conveyed to the fixing device 151 by the conveying belt 150. next,
The image formed on the back surface of the cut sheet S1 is
1 and is transported to the flapper 153 by the transport roller pair 152. Next, the cut sheet S1 is guided by the flapper 153 to the paper discharge roller pair 154, and is discharged onto the paper discharge tray 155 by the paper discharge roller pair 154.
Next, the third cut sheet S3 is fed from the paper cassette 146, and an image is formed on the surface by the above-described single-sided printing operation.
It is transported to the position. Hereinafter, by a similar operation, the sheet feeding and the sheet re-feeding from the sheet feeding cassette 146 and the re-feed roller pair 159 are alternately repeated, so that a predetermined number of double-sided cut sheets S are discharged. The paper is discharged onto the tray 155.

As described above, one-side printing is performed on the front surface of cut sheets that can be retained in the printing apparatus 100 (n sheets), and each time the back surface of the retained cut sheet is printed on one side, a new one is printed. By feeding a simple cut sheet and performing single-sided printing on the surface thereof, it is possible to perform double-sided printing by making full use of the recording paper conveying ability of the printing apparatus 100. The present invention is particularly applied to a printing apparatus having such a double-sided printing function. Such a double-sided printing function is referred to as an n-page double-sided printing mode according to the number n of sheets that can be retained. However, the order of printing in the n-page double-sided printing mode does not mean that the print data is printed in the order of the transmitted print data in page units.
For example, the second page print data, the fourth page print data, the first page print data, and the third page print data according to the number of pages of the print data transmitted at the start of the print processing at a certain point in time. And so on.

Next, the host computer 200 of the present invention.
The configuration of a printing system including the printer and the printing apparatus 100 will be described with reference to FIG. FIG. 2 is a block diagram showing the configuration of the printing system according to the embodiment of the present invention. still,
The printing system described in the present invention includes a host computer 200 and a printing apparatus 100. However, as long as the functions of the present invention can be realized, even if the system includes a plurality of devices, a network such as a LAN can be used. It is needless to say that the present invention can be applied to a system in which the processing is performed via the.

First, a detailed functional configuration of the printing apparatus 100 will be described. In FIG. 2, the printing apparatus 100
Is roughly divided functionally into a formatter control unit 110,
It comprises an operation panel 120, an output control unit 130, and a printer engine 140. The formatter control unit 110 includes an interface (I / F) unit 111
, Reception buffer 1121, and transmission buffer 1122
, Command analysis unit 113, print control processing execution unit 11
4, a drawing process execution unit 115, and a page memory 116.
, An output control unit 130, and a printer engine 140.

An interface (I / F) unit 111 is a communication unit with the host computer 200, and transmits and receives print data to and from the host computer 200.
The reception buffer 1121 is connected to the host computer 200
And temporarily stores and manages print data such as print information to be received. The transmission buffer 1122 temporarily holds and manages print data such as a print state to be transmitted to the host computer 200. The command analysis unit 113 analyzes the print data received by the reception buffer 1121. The print control processing execution unit 114 controls the print processing based on the analysis result of the command analysis unit 113. Drawing processing execution unit 115
Generates print data for forming an image on recording paper. The page memory 116 expands the print data generated by the drawing processing execution unit 115.

Next, an outline of the operation of the format control unit 110 will be described. First, the interface (I /
F) When the unit 111 receives print data from the host computer 200, the print data is temporarily stored in the reception buffer 1121 temporarily. The command is read by the command analysis unit 113 as necessary, and
It is processed into a command conforming to 00. Note that the command analysis unit 113 is configured by a control program conforming to each print control command system and print job control language. The commands analyzed by the command analysis unit 113 are roughly classified into commands related to an image actually formed on a recording sheet and commands related to control of a printing operation in the printing apparatus 100 for forming an image. And
A command related to the formation of an image such as a character, a graphic, or an image is passed to the drawing processing execution unit 115, and print data for forming an image is generated by the drawing processing execution unit 115.
Further, a command related to control of a printing operation in the printing apparatus 100 such as a paper feed selection or a reset command is passed to the print control processing execution unit 114, and print data for controlling the printing operation of the printing apparatus 100 is generated. .

The drawing process execution unit 115 sequentially develops print data such as characters, graphics, and images in the page memory 116 based on the command passed from the command analysis unit 113. The page memory 116 may be managed by the image signal expansion processing and the tracking of the image signal shipping to the printer engine 140, that is, banding control. If there is a sufficient storage area for storing the image signal, a storage area capable of developing the image signal for one page of the cut sheet may be secured. Also, generally, the formatter control unit 110
It is configured by a computer system having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and the like.
The processing executed by each component may be processed in a time-sharing manner under a multitask monitor (real-time OS), or a dedicated controller hardware may be prepared for each component. It may be processed independently.

The operation panel 120 is for setting and displaying various states of the printing apparatus 100. The output control unit 130 converts the print data developed in the page memory 117 into an image signal, and controls the output of the image signal to the printer engine unit 140. The printer engine section 140 is a printing mechanism section for forming a permanent visible image on a recording sheet based on the image signal input from the output control section 130, and has been described above with reference to FIG.

The functional configuration of the printing apparatus 100 has been described above. Next, the functional configuration of the host computer 200 will be described. In FIG. 2, a host computer 200 includes a keyboard 210 as an input device, a mouse 211 as a pointing device, and a display monitor 2 as a display device.
20, an interface (I / F) 230 serving as a communication unit with the printing apparatus 100 is configured as one computer system. The host
Computer 200 is MS_DOS, Windows
Operating under a basic OS such as Further, as described above, the host computer 200 outputs the print data including the print data and the control code to the printing apparatus 100.

In the host computer 200, focusing only on the functional parts related to the present invention, and the functions on the basic OS are roughly classified, the application software 201 and the Graphic Device I which are a part of the functions of the basic OS
nterface (hereinafter referred to as GDI) 202, print
The data may be divided into a processor 203, a printer driver 204, and a print spooler 205 that temporarily stores and processes data generated by the printer driver 204. In the embodiment of the present invention, it is assumed that the print processor 203 is located before the printer driver 204 and the print spooler 205 is located after the printer driver 204. In addition, these names and functional frameworks may be slightly different depending on the basic OS. However, as long as the module can realize the function of each component of the present invention, those names and frameworks are not a big problem for the present invention. Absent.

The print processor 203 of the present invention
Modules called Windows95 and Win95
This is unique to WindowsNT, and can be realized by a module called a print filter or the like in another basic OS. Also, the print spooler 205 can be realized by incorporating processing in a module called a print queue.

In general, these host computers 200 include a central processing unit (CPU), a read only memory (ROM), and a random access memory (R).
AM), a hard disk driver (HDD), various input / output control units (I / O), and other hardware, software called basic software controls the control, and the application software operates under the basic software. It is supposed to. Further, a print processor 203, a printer driver 204, a print spooler 205, and the like are also regarded as one of the application software. The application software 201 indicates application software that operates on basic software such as a word processor or a spreadsheet.

Here, the operation of the application software will be described by taking, for example, general word processing software as an example. The application software 201 mainly performs editing work of a document such as a text. And when printing the document,
A print menu is selected by the mouse 211 or the like, and printing is executed. Next, the application software 201
The GDI 202 which is a part of the function of the basic OS is called. The GDI 202 is a basic function group that controls the characteristics of a display device such as a screen display and a print output and a printing device. Then, the application software 201 uses the basic function group, and is unaware of the part depending on the model (hardware).
01 can be operated.

Next, the GDI 202 fetches information such as the drawing capability and print resolution of the printing apparatus from the printer driver 203 which manages information depending on the model of the printing apparatus. Then, the GDI function called from the application software 201 is analyzed. Next, intermediate print data called an extended metafile (EMF) 221 is generated, and the EMF 221 is temporarily spooled. When the generation of the EMF 221 is completed for all pages, the application software 201 is released from the processing, and the subsequent print processing is performed by a module called a print subsystem in the background.

In the print subsystem, first, the print processor 203 operates to read the EMF 221 temporarily spooled. Next, the read data stream of the EMF 221 is
2, the currently selected printer driver 20
Pass to 3. The printer driver 203 is a GDI 202
Based on the received EMF 221 and the print environment setting set by the graphical user interface (GUI) of the host computer 200 itself, printing including a command sequence and a data sequence conforming to the command system of the printing apparatus 100 is performed. Generate data. The generated print data is temporarily stored in the print spooler 204.

The print spooler 204 plays a role in accelerating the release of the processing of the print subsystem. That is, when print data is directly sent from the printer driver 204 to the printing apparatus 1, the receiving buffer 1121 of the printing apparatus 100 becomes full, or the communication unit goes offline due to some reason (for example, a paper jam (jam)). Then, host computer 2
From 00, the print data cannot be transmitted, and the print processing may be interrupted. However, if there is a means for temporarily storing print data like the printer spooler 204, first, the printer spooler 20
4, all print data can be ejected. As a result, application software 201 and print
The subsystem is released from print processing such as sequentially creating print data, and release of the processing can be expedited.

The print data created in this way is
After passing through the print spooler 205, the printing apparatus 10 passes through the I / F unit 230 of the host computer 200.
Sent to 0. At the same time, the I / F control unit 230
Receives print data such as a print state from the printing apparatus 100. As described above, each component constituting the printing system of the present invention has been described with reference to FIG. 2. Next, an operation performed in the present invention will be described with a specific example.

For example, Windows which is basic software
Word processing application software 20 running on
A case is considered in which a 5-page document created by activating the printer 1 is printed on both sides. When the application software 201 issues a print instruction to the host computer 200, the host computer 200 calls the GDI 202. The GDI 202 inquires of the capability of the printer driver 204 and generates an EMF 221 according to the capability. When the generation of the EMF 221 is completed for all pages, the application software 201 is released from the processing, and the subsequent printing processing is performed in the background.

First, the print processor 203, which reads the spooled EMF 221 and provides the GDI 202 with the data stream,
221 is performed. Note that the print processor 203 is a module that can also serve as a filter for extracting and processing information from the data stream during despooling. Further, a processing load predicting unit 203 according to the present invention described below.
a is realized by the print processor 203. More specifically, the processing load estimating unit 203a transmits the print data of each page to the printing apparatus 100, and estimates the processing time required immediately before the print data is expanded in the page memory 116.

Hereinafter, the processing executed by the present invention including the processing executed by the processing load estimating section 203a will be described with reference to the flowchart of FIG. FIG. 3 is a flowchart showing the processing flow of the processing executed in the embodiment of the present invention. First, in step S (1), a print job description file that controls a file for each page of a print job is opened. This print job description file is shown in FIG.
Is configured as follows.
One print job description file is generated. The position of a page data description file created for each page included in the print job is managed.

Next, in step S (2), the value of a variable i for counting the page number in the print job is initialized to indicate the first page. In step S (3), the location of the page data description file corresponding to the i-th page is obtained from the information of the print job description file, and the page data description file is opened. Step S
In (4), a data stream is identified for each object record from the opened page data description file. In step S (5), a predicted value of the processing time required for processing each object record is acquired from the processing time information prepared in advance based on the identification information for the data stream for each object record. Generally, even for the same object record, the processing time varies depending on the value of the parameter and the size of drawing. Then, in the embodiment of the present invention, a processing time such as a worst case processing time or an average processing time for processing the object record is checked in advance.
Then, a processing time appropriately tuned by giving a sufficient margin to the processing time is defined as a predicted value of the processing time required for processing the object record. The predicted value of the processing time is defined as a predicted value of the processing time when measured by a host computer having an average capability. Therefore, in practice, the environment of the printing system operating in the present invention and the host computer 20 are not required.
Since it depends on the capability of the host computer 200, the ratio between the host computer having the average capability defined above and the capability of the host computer 200 actually operating is separately calculated. Then, a predicted value of the processing time is calculated based on the calculated ratio (factor).

The processing capacity factor of the host computer 200 is calculated in advance by a simple calculation when the printer driver 204 is installed or when the print processor 203 is first started, and is stored in a storage medium such as a RAM. Shall be kept. Although it is technically possible to calculate a more precise predicted value of the processing time by strictly interpreting the object record with respect to the predicted value of the processing time, the total throughput of the entire printing system can be calculated. Because it can lead to
In the embodiments of the present invention, the point is to calculate an estimated value of the approximate processing time and to minimize the overhead for that.

The predicted processing time required for processing each object record calculated as described above is added to the already calculated predicted processing time of the object record in step S (6). Step S (7)
Then, it is determined whether or not the object record existing in the opened page data description file and for which the predicted value of the processing time has not been calculated is the final object record. If it is not the last object record (NO in step S (7)), the process returns to step S (4). on the other hand,
If it is the last object record (step S
(YES in (7)), the process proceeds to step S (8).

In step S (8), a predicted value of the processing time required for processing the calculated page data description file for one page is set in the table. Step S (9)
Then, referring to the information of the print job description file, it is determined whether or not the already processed page is the last page. If it is not the last page (NO in step S (9)), the process proceeds to step S (10). In step S (10), the content of a page counter i for counting the number of processed pages is incremented by one. Then, the process returns to step S (3). On the other hand, if it is the last page (YES in step S (9)), the process ends.

It is assumed that a predicted value as shown in FIG. 5 is obtained as a predicted value of the processing time for each page by the processing described above. Then, a process of switching the n-page double-sided print mode of the print engine 140 of the printing apparatus 100 adaptively according to the predicted value is executed by the double-sided print mode determining unit 203b. In the embodiment of the present invention, it is assumed that the processing executed by the double-sided printing mode determining unit 203b is also executed by the print processor 203, similarly to the processing executed by the processing load estimating unit 203a.

First, an optimal determination method for determining a criterion for switching the adaptive double-sided printing mode according to the predicted value of the processing time will be described with reference to FIG. FIG. 6 is a diagram for explaining the concept of an optimal determination method for determining a reference for switching the duplex printing mode according to the embodiment of the present invention. The basis for switching the duplex printing mode is m [PPM] (PPM =
Page Per Minutes). For example, consider switching between the two-sided printing mode in printing by a printing apparatus having a recording paper transport capacity of 3.2 [PPM] and printing by a printing apparatus having a recording paper transport capacity of 4.0 [PPM].

For example, print data is transmitted such that four pages are completed at the time of the checkpoint, one page is completed at the time of the checkpoint, and three pages are completed at the time of the checkpoint. In this case, the recording paper conveyance capacity is 4.0.
[PPM] printing apparatus can print in the 4-page duplex printing mode. However, even if four pages have been completed at the time of the checkpoint, the recording paper transport capacity is such that printing of the first page of print data cannot be completed in time of the checkpoint.
In the case of a printing apparatus of 2 [PPM], the total throughput cannot be improved even if printing is performed in the 4-page double-sided printing mode. Therefore, the recording paper transport capacity of 3.2 [PPM] when such print data is transmitted.
Printer must print in a two-page duplex mode.

As described above, as a criterion for selecting the n-page double-sided printing mode, the correspondence with the n-page double-sided printing mode that can be printed according to the predicted value of the processing time is prepared in advance as a table, and the table is prepared. By referring to this, an n-page double-sided printing mode corresponding to the calculated predicted value of the processing time is selected. When the recording paper conveyance capacity of the printer engine 140 is m [PPM], the predicted value of the processing time required for processing each page is (60 m) [sec].
c], it is possible to switch to the nmax page double-sided printing mode that makes the best use of the printer engine 140. In this case, it is not necessary to select the n-page double-sided printing mode by referring to the table.

For example, FIG. 5 shows an example of the predicted value of the processing time required for processing the print data for five pages created by the application software 201. This predicted value is shown in FIG. The n-sided double-sided printing mode to be selected in accordance with,, is determined. In this case, four pages have been printed at the time of the checkpoint, one page has been printed at the time of the checkpoint, and three pages have been printed at the time of the checkpoint. It is known in advance that printing is possible.

In the conventional method of transmitting print data in page order, at the time of a check point,
It can be seen that the printing process for four pages has not been completed.
In other words, in the present invention, the order of the printing process for each page is determined in advance so that the total throughput is optimized, so that there are no pages waiting to be printed in the printing apparatus 100, and efficient printing process can be performed. Further, the elimination of the output wait causes a problem that a sufficient margin cannot be obtained in a print process for a page to be printed in the printing apparatus 100, which has conventionally occurred due to the output wait in the printing apparatus 100. The problem of wasting a storage area for holding print data of a waiting page can be eliminated.

The double-sided printing mode determining unit 203 as described above
The data stream processing unit 203c executes processing for controlling the order in which print data for executing the n-page duplex printing mode selected in b is transmitted to the printing apparatus 100.
In the embodiment of the present invention, the processing executed by the data stream processing unit 203c is also performed by the processing load prediction unit 20c.
3a and the print processor 20
3 is executed.

As described above, the print job is managed by the print job description file. As for the page data description file for each page included in the print job description file, the page data description file included in the print job description file operates independently. This means that the printing environment settings such as the font attributes and paper used in the previously transmitted page data description file do not continue to form the next page data description file. Therefore, normally, the page data description file included in the print job description file is configured in a continuous page order from the first page, but this order may be changed to a discontinuous page order by operating the print job description file. Is basically no problem.

In view of such characteristics of the print job description file, the data stream processing unit 203
The page order of the page data description file included in the print job description file is changed according to the n-page double-sided print mode selected by the double-sided print mode determination unit 203b. Then, the printer driver 204 transfers the print job description file including the page data description file composed in the changed page order to the printer driver 204 via the GDI 202, and the printer driver 204 switches the n-page double-sided printing mode. It is possible to perform print processing as if performing normal print processing without being aware of it.

The outline of the present invention will be described below with reference to FIG. FIG. 8 is a diagram for explaining the outline of the embodiment of the present invention. In FIG. 8, before sending print data (pages 1 to 4) created by the application software 201 of the host computer 200 to the printer engine 140 of the printing apparatus 100, GD
The EMF 211 is created by I202. Then, the created EMF 221 is analyzed for each print job description file, and a predicted value of a processing time required for processing each page is calculated. Based on the calculated predicted processing time, an n-page double-sided processing mode for completing printing at least slightly faster than the worst case of the predicted total processing time is selected. In the case of FIG. 8, the four-page two-sided printing mode is selected in case 1, and the two-page two-sided printing mode is selected in case 2. However, at the time of network connection, the print data transmitted from the host computer does not necessarily reach the printing apparatus directly via various intermediate routes or due to the connection status of the line (so-called network traffic). Since such a disturbance factor cannot be taken into account in the predicted value calculated on the host computer side, in such an environment, the receiving buffer on the printing apparatus side should be made sufficiently large to accumulate n pages of data before processing. Or a network environment is constructed by an interface that guarantees real-time transfer as defined by the IEEE 1394 interface.

In the embodiment of the present invention, the printing system including the printing apparatus 100 locally connected to the host computer 200 has been described. However, the host computer 200 and the printing apparatus 100 are connected via a network. The present invention can be applied to such cases. In this case, the print processing prediction unit 20
Each of the components 3a, the double-sided printing mode determination unit 203b, and the data stream processing unit 203c may be configured to be distributed and processed on another computer on a network path. In this case, the data stream processing unit 203c can also perform processing such as searching for a printing apparatus capable of performing double-sided printing at the nearest printing apparatus on the network and automatically assigning a processing destination.

Further, the present embodiment has been described on the premise that a printing apparatus for monochrome printing is used, but the present invention is also applicable to a printing apparatus capable of color printing. As described above, according to the present embodiment, the host computer 200
When controlling double-sided printing executed by the printing apparatus 100, a predicted value of a processing time required for processing each page of print data is calculated in advance. When the processing of the predetermined number of pages in the host computer precedes the printing processing of the printing apparatus 100, the optimal processing is performed before the print data is transmitted to the printing apparatus 100 so that the highest total throughput is obtained. Since the operation of changing the page order of the print data is performed and the mode is positively switched to the n-page double-sided printing mode, the total throughput of the printing system can be improved.

Further, unnecessary buffering of print data is eliminated, and there is an excellent effect that the same page memory 116 can be used for single-sided printing and double-sided printing. Accordingly, the page memory 116 to be mounted on the printing apparatus 100
The storage area required for the product is reduced, and a product having an advantage in terms of price can be manufactured. Further, since the host computer 200 controls double-sided printing, which is a part of the processing load of the conventional printing apparatus, the total amount of time required until a print result is obtained in accordance with the hardware performance (processing capability) of the host computer 200. Throughput can be dramatically improved. For this reason, the printing device 10
In an environment such as a personal computer or a network where it is clear that the performance will be further improved in the future without depending on the performance of a single unit, it is expected that the effect realized by the present invention will increase in proportion to the environment. .

Even if the present invention is applied to a system composed of a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), an apparatus (for example, a copier, a facsimile, etc.) comprising one device Device). Further, an object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and a computer (or CPU or MPU) of the system or apparatus to store the storage medium. Needless to say, this can also be achieved by reading and executing the program code stored in the program.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. As a storage medium for supplying the program code, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk,
A CD-ROM, CD-R, magnetic tape, nonvolatile memory card, ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instruction of the program code. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the program code is read based on the instruction of the program code. It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the above-described flowcharts. Each module shown will be stored in a storage medium. That is, the program codes of at least the “calculation module”, “selection module”, and “change module” may be stored in the storage medium.

The "calculation module" calculates the predicted value of the processing time of the print data created on the information processing apparatus. The “selection module” selects a duplex printing mode of the printing apparatus based on the calculated predicted value. The “change module” changes the configuration of the data stream of the print data based on the selected duplex printing mode.

[0068]

As described above, according to the present invention,
In a printing system having a two-sided printing mechanism, it is possible to provide a printing system, a control method thereof, and an information processing apparatus capable of improving the total throughput without increasing the cost.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a basic configuration of a printing apparatus having a duplex printing mechanism according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a printing system according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating a processing flow of processing executed in the embodiment of the present invention.

FIG. 4 is a diagram showing a relationship between a print job description file and a page description file according to the embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of a predicted value of a processing time for each page according to the embodiment of this invention.

FIG. 6 is a diagram for explaining the concept of an optimal determination method for determining a reference for switching between two-sided printing modes according to the embodiment of the present invention.

FIG. 7 is a diagram for determining an n-page double-sided printing mode to be selected in the embodiment of the present invention.

FIG. 8 is a diagram for explaining an outline of an embodiment of the present invention.

FIG. 9 is a diagram showing a structure of a memory map of a storage medium storing a program code for realizing an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 100 printing device 110 formatter control unit 111 interface 1121 reception buffer 1122 transmission buffer 113 command analysis unit 114 print control processing execution unit 115 drawing processing execution unit 116 page memory 120 operation panel 130 output control unit 140 printer engine unit 14 image forming unit 141 semiconductor laser 142 laser beam 143 rotating polygon mirror 144 electrostatic drum 145 developing unit 146 paper feed cassette 147 paper feed roller 148 transport roller pair 149 transport roller pair 150 transport belt 151 fixing device 152 transport roller pair 153 flapper 154 discharge roller pair 155 Output tray 156 Front / reverse path 157 Transport roller pair 158 Re-feed roller pair 200 Host computer 201 Application software 02 GDI 203 print processor 203a processing load prediction unit 203b duplex print mode determination unit 203c the data stream processing unit 204 print driver 205 print spooler 210 keyboard 211 mouse 220 display monitor 230 Interface

Claims (25)

[Claims] 1. A printing system comprising: an information processing apparatus; and a printing apparatus having a double-sided printing function capable of performing double-sided printing in a plurality of types of double-sided printing modes, the printing system comprising: A calculating unit that calculates a predicted value of the processing time; a selecting unit that selects a double-sided printing mode of the printing apparatus based on the predicted value calculated by the calculating unit; and a double-sided printing mode selected by the selecting unit. On the basis of,
Changing means for changing the configuration of the data stream of the print data. 2. The printing system according to claim 1, further comprising an output unit that outputs the data stream changed by the changing unit to the printing device. 3. The printing system according to claim 1, wherein the print data is configured in page units. 4. The printing system according to claim 3, wherein the page is configured in an object record unit. 5. The printing system according to claim 4, wherein said calculating means includes a table for managing values corresponding to each of a plurality of types of object records. 6. The calculation means acquires a value corresponding to an object record constituting a page constituting the print data from the table, and assigns a coefficient indicating a processing capability of the information processing apparatus to the acquired value. The printing system according to claim 1, wherein the integrated value is calculated as the predicted value. 7. The printing system according to claim 1, wherein the information processing device and the printing device are locally connected. 8. The printing system according to claim 1, wherein the information processing device and the printing device are connected via a network line. 9. A method for controlling a printing system having an information processing apparatus and a printing apparatus having a duplex printing function capable of performing duplex printing in a plurality of types of duplex printing modes, comprising: A calculating step of calculating a predicted value of the processing time of the print data; a selecting step of selecting a double-sided printing mode of the printing apparatus based on the predicted value calculated in the calculating step; and both sides selected in the selecting step Based on the print mode,
And a changing step of changing a configuration of a data stream of the print data. 10. The method according to claim 9, further comprising an output step of outputting the data stream changed in the change step to the printing device. 11. The method according to claim 9, wherein the print data is configured in page units. 12. The method according to claim 11, wherein the page is configured in an object record unit. 13. The method according to claim 12, wherein the calculating step includes a table for managing values corresponding to a plurality of types of object records. 14. The calculating step obtains a value corresponding to an object record forming a page constituting the print data from the table, and assigns a coefficient indicating a processing capability of the information processing apparatus to the obtained value. The method according to claim 9, wherein the integrated value is calculated as the predicted value. 15. The information processing apparatus and the printing apparatus,
The method according to claim 9, wherein the printing system is locally connected. 16. The information processing apparatus and the printing apparatus,
The method according to claim 9, wherein the printing system is connected via a network line. 17. An information processing apparatus for outputting print data to a printing apparatus having a double-sided printing function capable of performing double-sided printing in a plurality of types of double-sided printing modes, wherein a predicted value of a processing time of the print data is calculated. Calculating means, a selecting means for selecting a two-sided printing mode of the printing apparatus based on the predicted value calculated by the calculating means, and a data stream of the print data based on the two-sided printing mode selected by the selecting means. And a changing unit for changing the configuration of the information processing apparatus. 18. The information processing apparatus according to claim 17, further comprising an output unit that outputs the data stream changed by the changing unit to the printing device. 19. The information processing apparatus according to claim 17, wherein the print data is configured in page units. 20. The information processing apparatus according to claim 19, wherein the page is configured in an object record unit. 21. The information processing apparatus according to claim 20, wherein said calculating means includes a table for managing values corresponding to each of a plurality of types of object records. 22. The calculation means acquires a value corresponding to an object record constituting a page constituting the print data from the table, and assigns a coefficient indicating the processing capability of the information processing apparatus to the acquired value. The information processing apparatus according to claim 17, wherein the integrated value is calculated as the predicted value. 23. The information processing apparatus according to claim 17, wherein the information processing apparatus is locally connected to the printing apparatus.
An information processing apparatus according to claim 1. 24. The information processing apparatus according to claim 17, wherein the information processing apparatus is connected to the printing apparatus via a network line. 25. A computer readable memory storing a program code for controlling a printing system having an information processing device and a printing device having a duplex printing function capable of duplex printing in a plurality of types of duplex printing modes, Selecting a double-sided printing mode of the printing apparatus based on a program code of a calculation step of calculating a predicted value of a processing time of the print data created on the information processing apparatus, and the predicted value calculated in the calculation step; Based on the program code of the selecting step, based on the duplex printing mode selected in the selecting step,
And a program code for a change step of changing a configuration of a data stream of the print data.