Abstract:
The present invention realizes resource saving and energy saving by grasping and managing a usage efficiency of an image forming apparatus. To accomplish this, a method in accordance with the present invention is an information processing method of managing usage information on a job which is issued from an information processing apparatus to an image forming apparatus, which includes: a step of acquiring the usage information from the information processing apparatus or the image forming apparatus; a step of deriving the number of logical pages and the number of physical sheets from the usage information acquired in the acquisition step; and a step of outputting usage efficiency information of the image forming apparatus using the number of logical pages and the number of physical sheets derived in the derivation step.

Description:
This application is a continuation application of application Ser. No. 10/717,451, now allowed, filed Nov. 21, 2003, which is incorporated herein by reference. 

   FIELD OF THE INVENTION 
   The present invention relates to a technique for managing use of an image forming apparatus. 
   BACKGROUND OF THE INVENTION 
   Conventionally, there have been known systems for managing use of an image forming apparatus (see Japanese Patent Laid-Open No. 11-110156). Basically, the image forming apparatus is used freely at users discretion. As concerns to environmental problems increase recently, it is required to enhance efficient use of the image forming apparatus and to reduce consumption of resources and energy. 
   However, an administrator has no data for determining how efficient a user uses the image forming apparatus. Thus, the administrator cannot perform in-depth management of use of the image forming apparatus from the point of view of resource saving and energy saving. 
   SUMMARY OF THE INVENTION 
   Accordingly, an aspect of the present invention is to manage a efficient of usage of image processing apparatus. 
   According to the present invention the foregoing aspect is attained by providing an information processing method of managing usage of information on a job issued to an image forming apparatus from an information processing apparatus, the information processing method comprising: 
   a step of acquiring the usage information from the information processing apparatus and the image forming apparatus; 
   a step of deriving the number of logical pages and the number of physical pages from the usage information acquired in the acquisition step; and 
   a step of outputting information on usage efficiency of the image forming apparatus using the number of logical pages and the number of physical pages derived in the deriving step. 
   Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures there. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram showing a structure of a job account system in accordance with an embodiment of the present invention; 
       FIG. 2  is a block diagram showing a hardware configuration of a computer constituting the job account system; 
       FIG. 3  is a diagram showing a memory map of a RAM of the computer constituting the job account system; 
       FIG. 4  is a diagram showing a memory map of a storage medium for realizing the job account system; 
       FIG. 5  is a diagram showing load from the storage medium of the job account system; 
       FIG. 6  is a block diagram showing a hardware configuration of an image forming apparatus constituting the job account system; 
       FIG. 7  is a flowchart showing processing for acquiring print information of the job account system; 
       FIG. 8  is a flowchart showing processing for acquiring history in an apparatus of the job account system; 
       FIG. 9  is a flowchart showing processing for acquiring history in an apparatus of the job account system; 
       FIG. 10  is a flowchart showing processing for calculating a saving ratio of the job account system; 
       FIG. 11  is a flowchart showing processing for calculating a saving ratio of the job account system; 
       FIG. 12  is a flowchart showing processing for calculating a saving ratio of the job account system; and 
       FIG. 13  is a flowchart showing processing for calculating a saving ratio of the job account system. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Preferred embodiments of the present invention will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of the components, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless it is specifically stated otherwise. 
   Note that job information in this specification refers to information on a job issued to an information forming apparatus such as a printer from a computer. Print information refers to information on a result of printing in the image forming apparatus such as a printer. Plural pieces of print information arranged in a form of a history are referred to as a print history. In addition, usage information refers to information indicating how the image forming apparatus is used. Basically one piece of usage information is obtained for one job. In the case in which the print information cannot be acquired from the image forming apparatus, only the job information is included in the usage information. In the case in which the job information cannot be acquired from the computer, only the print information is included in the usage information. In addition, in the case in which the job information from the computer and the print information from the image forming apparatus can be acquired for one job, the job information and the print information are combined to form the usage information. Further, a usage history is a history of the usage information and includes plural pieces of usage information. 
   &lt;Job Account System&gt; 
     FIG. 1  is a basic diagram of an entire job account system shown as this embodiment. Reference numerals  1010  and  1020  denote client computers. Reference numeral  1030  denotes a server computer serving as an information processing apparatus. 
   Reference numerals  1040  and  1060  denote printers shown as an example of the image forming apparatus. Note that the printer  1040  includes a function of holding a print history (print history holding function), and the printer  1060  does not include the print history holding function. Reference numeral  1050  denotes an MFP (Multi Function Printer). The MFP  1050  is provided with a printer function, a copy function, a scanner function, and the print history holding function. 
   The computers  1010 ,  1020 , and  1030  and the printers  1040 ,  1050 , and  1060  can communicate with other apparatuses via a network. 
   (Software Configuration of the Client Computers) 
   The client computers  1010  and  1020  include applications  1011  and  1021 , which edit a document, an image, or the like and issue a print request, GDIs (Graphics Device Interfaces)  1012  and  1022 , which receive the print request from the applications  1011  and  1021  and output print data to a printer, and spoolers  1013  and  1023 . In addition, the client computers  1010  and  1020  include job account client applications  1014  and  1024 , which hook a Windows (registered trademark)—GDI function in the case of requesting printing from the applications  1011  and  1021  to acquire job information. 
   The job information includes the number of sheets to be printer, the number of pages, a size of printing, a type of a sheet to be used, information on a user who has issued a print request, color print information, a page layout (Number up), and information on double sides or one side. However, not all of these pieces of information are always included, and only the number of pages is included depending upon an environment or an apparatus. 
   The information such as the number of pages and the number of sheets included in the job information, which can be acquired by the client computers  1010  and  1020  are those requested from the applications  1011  and  1021 . Thus, if a page layout function or a double side recording function is used, the number of pages and the number of sheets may be different from the number of pages and the number of sheets of a recording material which is actually outputted. Therefore, here, the number of pages and the number of sheets included in the job information are referred to as the number of logical pages and the number of logical sheets, which are distinguished from the number of physical pages and the number of physical sheets in the recording material which is actually outputted. 
   When the application  1011  calls the GDI  1012  in the client computer  1010 , the GDI  1012  generates print data in response to an instruction from the application  1011  and sends the print data to the spooler  1013 . The job account client application  1014  watches (hooks) the application  1011  calling the GDI  1012  and accumulates job information for the print data. 
   The spooler  1013  communicates with the printer  1040 , the MFP  1050 , and the printer  1060  via a network and, if these apparatuses are in a ready state, sends print data to the apparatuses. 
   The job account client application  1014  periodically sends the accumulated job information to the job account server application  1031 . 
   In the client computer  1020 , the application  1021 , the GDI  1022 , and the spooler  1023  operate in the same manner as the application  1010 , the GDI  1012 , and the spooler  1013 , respectively. 
   The job account client application  1024  periodically watches the spooler  1023 . If there is a print job spooled by the spooler  1023 , the job account client application  1024  uses an API (Application Program Interface) to acquire job information. More specifically, the job account client application  1024  acquires the number of discharged sheets and the number of pages of the print job. Then, the job account client application  1024  sends the accumulated job information to the job account server application  1031 . 
   If an OS includes a function of communicating a change in a state to other applications, the job account client application  1024  does not have to periodically watch the spooler  1023 . It is sufficient that the OS informs the job account client application  1024  that a print job is spooled by the spooler  1023 . 
   (Software Configuration of the Server Computer) 
   On the other hand, the server computer  1030  includes a database  1032  for storing user information  1032   a , apparatus information  1032   b , and usage history information  1032   c . The user information  1032   a  includes a computer login name and a network login name of a user using an apparatus and provides information specifying a user who used the apparatus. The apparatus information  1032   b  includes a print speed, color information, and a network address of an apparatus. 
   In addition, the server computer  1030  includes a user information management module  1031   a , an apparatus information management module  1031   b , an usage information management module  1031   c , a usage state input/output module  1031   d , and a saving ratio calculation module  1031   e.    
   The user information management module  1031   a  stores the user information  1032   a  in the database  1032  in the server computer  1030  and manages the same. 
   In addition, the apparatus information management module  1031   b  checks whether or not a printer connected to a network has the print history holding function. Then, the apparatus information management module  1031   b  stores information on an apparatus, which has the print history holding function, and other apparatus information in the database  1032  in the server computer  1030  as the apparatus information  1032   b  and manages the same. 
   The user information management module  1031   c  receives job information from the job account client applications  1014  and  1024  and stores the job information in the database  1032  as the usage history information  1032   c.    
   Further, the usage information management module  1031   c  requests usage history information from the printer  1040 , the MFP  1050 , or the like having a function of holding usage history information therein, acquires the usage history information via the usage state input/output module  1031   d , and adds the usage history information to the usage history information  1032   c  existing in the database  1032 . This processing may be periodically performed, or may be performed from the apparatus side at the point when a capacity of an area storing the usage history information in the printer  1040  or the MFP  1050  has decreased. Usage information included in the usage history information held in the apparatus is essentially of the same nature as the job information and includes the number of sheets to be printed, the number of pages, a size of printing, a type of a sheet to be used, information on a user who has issued a print request, color print information, a page layout (Number up), and information on double-sided printing or one-side printing. However, only the number of pages may be held as the usage information depending upon an environment or an apparatus. 
   The usage information held in an apparatus includes the number of physical pages and sheets which the apparatus has actually outputted. 
   The usage state input/output module  1031   d  acquires usage history information from an image forming apparatus having the usage history holding function. In addition, the usage state input/output module  1031   d  can also output a usage state report (a report indicating which user has executed how many jobs, etc.) to a printer or a monitor. 
   Therefore, an administrator can cause the usage state input/output module  1031   d  to output a usage state and obtain the usage state of the image forming apparatus. The usage state input/output module  1031   d  outputs various usage states on the basis of the user information, the apparatus information, and the usage history information stored in the database  1032 . The administrator designates an output form of the usage states which the usage state input/output module  1031   d  adopts. Note that the output of the usage states is displayed on a display (not shown) of the server computer  1030 . In addition, usage state data may be sent to the client computer  1010  or  1020  to display an output of the usage state on a display (not shown) of the client computer. 
   As a usage state report, a usage amount for each user (the number of sheets and an amount of toner used for an output) and a usage time of the image forming apparatus can be outputted. In addition, it is also possible to output a usage state for each operation mode (function) of the image forming apparatus such as color print or double-sided printing. Further, it is also possible to output a usage state for each size of a sheet used for printing or a type of the sheet. 
   In addition, in the case in which a usage fee of a printer is set in the apparatus information, the fee is outputted for each printer or each user. Moreover, since a usage fee for each operation mode, a usage fee for each sheet size, and a usage fee for each type of a sheet are set, a user who performed printing, a sheet on which the printing was applied, an operation mode in which the printing was performed, an amount of printing, and an usage amount of the printer can be outputted. Note that, usually, an object of charging is the number of physical pages (so-called number of faces of sheets). 
   Further, the saving ratio calculation module  1031   e  calculates a saving ratio as a kind of usage efficiency information on the basis of the usage history information  1032   c  and passes the saving ratio to the usage state input/output module  1031   d  to output it to a display apparatus in the outside. There are two kinds of saving ratios, namely, a page saving ratio and a number of sheets saving ratio. The page saving ratio is a saving ratio of physical pages with respect to logical pages. In the case in which a job is issued for document data with twelve logical pages, 2-up setting for printing two logical pages for one physical page is performed. Further, in the case in which double-sided printing is set, the number of logical pages is twelve, the number of physical pages is six, and the number of physical sheets is three. Therefore, the page saving ratio is calculated as (12−6)/12=½, and the number of sheets saving ratio is calculated as (12−3)/12=¾. The number of sheets saving ratio represents saving of recording sheets, and the page saving ratio represents saving of charge or a recording agent (toner or ink). Therefore, in this example, it can be indicated on a monitor or the like of the server computer  1030  that “the number of outputted sheets could be saved by ¾, and charge could be saved by ½”. 
   Note that the saving ratio calculation module  1031   e  can automatically switch a calculation method of the saving ratio according to usage information to be an object of calculation. 
   Note that, although a display screen showing the saving ratio can be displayed after calculating the saving ratio in the saving ratio calculation module  1031   e , it is also possible to calculate the page saving ratio and the number of sheets saving ratio on the basis of the number of logical pages, the number of physical pages, and the number of physical sheets, which are calculated job information acquired from various routes. 
   For example, a case in which a user  1 , a user  2 , and a user  3  are registered in a job account system will be considered. In this case, for example, it is assumed that the user has outputted 1000 logical pages, 500 physical pages, and 300 physical sheets. Based upon the above-described calculation method, the saving ratio calculation module  1031   e  calculates the page saving ratio for the user  1  as 50% and the number of sheets saving ratio for the user  1  as 70%. In the case in which the user  2  has outputted 2000 logical pages, 400 physical pages, and 200 physical sheets, the saving ratio calculation module  1031   e  calculates the page saving ratio as 80% and the number of sheets saving ratio as 90%. In the case in which the user  3  has outputted 500 logical pages, 300 physical pages, and 250 physical sheets, the saving ratio calculation module  1031   e  calculates the page saving ratio as 40% and the number of sheets saving ratio as 50%. The usage state input/output module  1031   d  receives a list, in which user names of the user  1 , the user  2 , and the user  3 , the number of logical pages, the number of physical pages, the number of physical sheets, and the number of sheets saving ratio of the respective users are associated with each other, from the saving ratio calculation module  1031   e . Moreover, the usage state input/output module  1031   d  can also be constituted so as to control processing for displaying the list in a table format on the job account server. In this case, the display processing may be controlled such that a user name of a user, whose usage efficiency including the number of sheets saving ratio and the page saving ratio is equal to or lower than that set in advance, is displayed in an identifiable manner. 
   &lt;Control Configuration of a Computer&gt; 
     FIG. 2  is a diagram showing a hardware configuration of the client computer  1010 , the client computer  1020 , and the server computer  1030 . 
   Reference numeral  201  denotes a CPU (central processing unit). The CPU  201  performs control and arithmetic processing of the entire computer apparatus. 
   Reference numeral  202  denotes a ROM (read only memory). The ROM  202  is a storage area having stored therein information on a system startup program or the like. Reference numeral  203  denotes a RAM (random access memory). The RAM  203  is a storage area without limitation of use. An operating system (OS), an application program, a device driver (printer driver), a program for communication control, and the like are loaded to the RAM  203  and executed by the CPU  201 . 
   Reference numeral  204  denotes a KBC (keyboard controller). The KBC  204  receives input data from a keyboard (not shown) attached to the computer and communicates the input data to the CPU  201 . Reference numeral  205  denotes a CRTC (display controller). The CRTC  205  applies display control to a not-shown display. Reference numeral  206  denotes a HD (hard disk). Note that the HD  206  can be replaced by or used with an external storage device such as a FD (floppy (registered trademark) disk), an SRAM (nonvolatile memory), or the like. The HD  206  stores a program and data, which are loaded to the RAM  203  as required. For example, in the case of the HD in the server computer  1030 , user information, apparatus information, and usage history information are stored therein. 
   Reference numeral  207  denotes a communication unit, which controls network communication. With this communication unit  207 , the computer is capable of communicating with other computers and image forming apparatuses connected to the network. 
   Reference numeral  208  denotes a system bus. Data exchanges among the above-described components pass through this system bus  208 . 
   &lt;Memory Map&gt; 
     FIG. 3  is a diagram showing a memory map in a state in which a job account server application is loaded to the RAM  203  and is executable by the CPU  201 . Reference numeral  301  denotes a basic I/O program. Reference numeral  302  denotes an operating system such as a Windows system. Reference numeral  304  denotes a related data of the job account server application  1031 . Reference numeral  305  denotes a work area which the CPU  201  uses when it executes various programs. 
   The server computer  1030  operates as the basic I/O program  301 , the operating system  302 , and the job account server application  1031  are executed. The basic I/O program  301  is stored in the ROM  202  of  FIG. 2 . The operating system  302  and the job account server application  1031  are stored in the HD  206 . When a power supply of the apparatus is applied, the operating system  302  and the job account server application  1031  are read in the RAM  203  from the HD  206  according to an IPL (initialize program loading) function in the basis I/O program  301  and started to operate. 
   Note that the job account server application  1031  and the related data  304  are stored in a flexible disk (FD) or a CD-ROM and supplied to the computer from the same.  FIG. 4  is a diagram showing a memory map in a state in which a job account server application and related data are stored in an FD or a CD-ROM. A storage area  400  of the FD or the CD-ROM includes volume information  401 , directory information  402 , an execution file  403  of the job account server application, and a related data file  404  of a job account. 
   That is, the server computer  1030  is constituted by supplying a storage medium  500  such as an FD or a CD-ROM provided with the memory map shown in  FIG. 4  to a disk driver  501  of a computer  502  as shown in  FIG. 5  and installing a job account server application stored in the storage medium  500  in the HD  206  of the computer. Then, various effects are realized by the CPU  201  reading out and execute a program code stored in the HD  206 . In this case, the program code itself read out from the storage medium  500  realizes the function of the embodiment, and the storage medium  500  having the program code stored therein constitutes the present invention. 
   As a storage medium for supplying a program code, an optical disk, a magneto-optical disk, a CD-R, a magnetic tape, a nonvolatile memory card, ROM car, HD card, and the like can be used other than the CD-ROM and the flexible disk. In addition, the function of the embodiment is not only realized by the computer reading out the read out program. It is needless to mention that the OS (operating system) or the like running on the computer performs a part or all of actual processing on the basis of an instruction of the program code, and the function of the embodiment is also realized by the processing. Moreover, it is needless to mention that, after the program code read out from the storage medium is written in a memory provided in a function extended board inserted in the computer or a function extended unit connected to the computer, a CPU provided in the function extended board or the function extended unit performs a part or all of actual processing on the basis of an instruction of the program code, and the function of the embodiment is realized by the processing. 
   &lt;Hardware Configuration of the Image Forming Apparatus&gt; 
     FIG. 6  is a diagram showing a schematic structure of the image forming apparatus. Reference numeral  605  denotes a controller unit for controlling the entire image forming apparatus. The controller unit  605  includes a CPU  601 , a ROM  602 , a RAM  603 , and a HD  604 . 
   The CPU  601  performs control and arithmetic processing of the controller unit and the entire image forming apparatus. The ROM  602  is a read only memory, which is a storage area for storing a system startup program or the like. The RAM  603  is a random access memory, which is a data storage area. The HD  604  is a hard disk, which can be replaced by or used with another nonvolatile storage device such as an SRAM. The image forming apparatus having the job history holding function stores a job history in the RAM  603  or the HD  604 . In addition, an operating system, a program for communication control, and a program for engine control are loaded to the RAM  603  and executed by the CPU  601 . 
   Reference numeral  606  denotes an engine unit of the image forming apparatus, which performs a print operation and an image reading operation under the control of the controller unit  605 . The engine unit  606  includes a printer engine or a scanner engine, or both of the engines. 
   Reference numeral  607  denotes a communication unit, which controls network communication. With this communication unit  607 , the image forming apparatus is capable of communicating with the client computer and the server computer. Reference numeral  608  denotes a system bus. Data exchanged among the above-described components passes through the system bus  608 . 
   &lt;Operation of the Client Computer&gt; 
   An operation of the client computer  1010  of this embodiment will be described with reference to a flowchart of  FIG. 7 . This flowchart shows the case of print output. 
   First, the client computer  1010  performs print designation of a document which a user desires to print. The print designation means designation of an output printer and designation of an output range, the number of output copies, and the like. After the print designation, the client computer  1010  executes actual printing (step S 100 ). The client computer  1010  judges appropriateness of a print request on the basis of contents of the print designation in step S 100  (S 101 ). 
   In step S 102 , in order to perform appropriate print management, the client computer  1010  acquires the number of sheets to be printed, a page layout, information on double sides, and user information as job information. 
   In step S 103 , the client computer  1010  sends the job information acquired in step S 102  to the server computer. Thereafter, if the user does not cancel the print processing, the client computer  1010  proceeds to step S 104  and actually sends a print request to the apparatus. 
   &lt;Usage History Acquisition Operation of the Server Computer&gt; 
   A usage history acquisition operation to be performed by the usage information management module  1031   c  of the server computer  1030  of this embodiment will be described with reference to flowcharts of  FIGS. 8 and 9 . 
     FIG. 8  is a flowchart showing processing in the case in which the server computer  1030  acquires a usage history automatically. 
   The usage information management module  1031   c  performs processing for print history information acquisition from the apparatus such as the printer  1040  or the printer  1050  for each designated period. That is, in step S 201 , the usage information management module  1031   c  confirms whether or not it is time for executing the processing for print history information acquisition. If it is the time for acquisition, in step S 202 , the usage information management module  1031   c  collects print history information from the apparatus and registers the information in the database  1032  as the usage history information  1032   c.    
     FIG. 9  is a flowchart showing processing in the case in which the server computer  1030  acquires a print history in response to an instruction of the apparatus. 
   In step S 301 , the server computer  1030  confirms whether or not an event of print history information acquisition is generated by the apparatus. If the event has been generated, the server computer  1030  acquires print information in step S 302  and registers the print information in the database  1032  as the usage history information  1032   c . If the event has not been generated, in step S 303 , the server computer  1030  confirms whether or not an end request has been received. If the end request has been received, the server computer  1030  ends the processing. If the end request has not been received, the server computer  1030  returns to step S 301  and repeats the processing for event generation confirmation. 
   &lt;Processing of the Saving Ratio Calculation Module&gt; 
   Processing for calculating a saving ratio to be performed by the saving ratio calculation module  1031   e  will be described with reference to a flowchart of  FIG. 10 . 
   First, in step S 400 , the saving ratio calculation module  1031   e  reads out one piece of usage information, which becomes an object of saving ratio calculation, from the usage history information  1032   c  of the database  1032 . In step S 401 , the saving ratio calculation module  1031   e  judges whether or not the usage information includes a print history acquired from the apparatus. If the usage information does not include the print history, sine the usage information is usage information including only job information acquired by the client computers  1010  and  1020 , in step S 403 , the saving ratio calculation module  1031   e  calculates a saving ratio according to only the job information. 
   If it is judged in step S 401  that the print information is included, the saving ratio calculation module  1031   e  proceeds to step S 402  and judges whether or not the job information acquired by the client computers  1010  and  1020  is included in the usage information. 
   If the job information is not included, the saving ratio calculation module  1031   e  proceeds to step S 404  and calculates a saving ratio according to only the print information acquired from the apparatus. 
   If the job information is included, in step S 405 , the saving ratio calculation module  1031   e  calculates a saving ratio according to both the print information from the apparatus and the job information from the client computers  1010  and  1020 . 
   When the calculation of the saving ratio ends, in step S 406 , the saving ratio calculation module  1031   e  outputs the saving ratio to the database  1032  or the usage state input/output module  1031   d.    
   Then, in step S 407 , the saving ratio calculation module  1031   e  judges whether or not the calculation processing has been finished for all pieces of usage information to be objects of the saving ratio calculation. If the calculation processing has not been finished, the saving ratio calculation module  1031   e  returns to step S 400 . If the calculation processing has been finished, the saving ratio calculation module  1031   e  ends the processing of  FIG. 10 . 
   Note that the saving ratio calculation module  1031   e  may calculate a saving ratio in advance and store the saving ratio as a part of usage history information or may calculate a saving ratio on the basis of stored usage history information in response to an output request for a saving ratio from the user and output the saving ratio using the usage state input/output module  1031   d.    
   (Saving Ratio Calculation from Job Information) 
   Next, saving ratio calculation processing, which is performed in step s 403 , will be described with reference to  FIG. 11 .  FIG. 11  is a flowchart showing processing for calculating a saving ratio only from job information. It is assumed that this job information includes at least information on the number of logical pages. 
   In step S 501 , the saving ratio calculation module  1031   e  judges whether or not page layout information (information of contents for laying out the Nup number of logical pages in one physical page) is included in the job information. If the page layout information is included, in step S 502 , the saving ratio calculation module  1031   e  divides the number of logical pages in the job information with the Nup number to thereby calculate the number of physical pages which seems to be actually outputted. If it is judged in step S 501  that the page layout information is not included, in step S 503 , the saving ratio calculation module  1031   e  regards the number of logical pages as the number of physical pages. 
   In step S 504 , the saving ratio calculation module  1031   e  judges whether or not double-sided printing/one-side printing information is included in the job information. If the double-sided printing/one-side printing information is included, in step S 505 , the saving ratio calculation module  1031   e  judges whether the job is a job for performing double-sided printing. If the job is the job for performing double-sided printing, in step S 506 , the saving ratio calculation module  1031   e  divides the number of physical pages by two to thereby calculate the number of physical sheets. If the double-sided printing/one-side printing information is not included, or if the job is not for double-sided printing, the saving ratio calculation module  1031   e  regards the number of physical pages as the number of physical sheets. 
   Then, in step S 508 , the saving ratio calculation module  1031   e  substitutes the number of logical pages, the number of physical pages, and the number of physical sheets calculated in the above-described processing in the expression [page saving ratio=(number of logical pages−number of physical pages)/number of logical pages], whereby a page saving ratio is calculated. In addition, in step S 509 , the saving ratio calculation module  1031   e  substitutes the number of logical pages, the number of physical pages, and the number of physical sheets calculated in the above-described processing in the expression [number of sheets saving ratio=(number of logical pages−number of logical sheets)/number of logical pages], whereby a number of sheets saving ratio is calculated. 
   (Saving Ratio Calculation from Print Information) 
   Next, processing for saving ratio calculation, which is performed in step S 404 , will be described with reference to  FIG. 12 .  FIG. 12  is a flowchart showing processing for calculating a saving ratio only from print information. Here, it is assumed that at least the number of physical sheets is included in the print information. 
   In step S 601 , the saving ratio calculation module  1031   e  judges whether or not page layout information (Nup) is included in the print information. If the page layout information is included, in step S 602 , the saving ratio calculation module  1031   e  multiplies the number of physical pages in the print information by the Nup number to thereby calculate the number of logical pages which seems to be requested by an application. If it is judges in step S 601  that the page layout information is not included, in step S 603 , the saving ratio calculation module  1031   e  regards the number of physical pages as the number of logical pages. 
   In step S 604 , the saving ratio calculation module  1031   e  judges whether or not double-sided printing/one-side printing information exists in the print information. If the double-sided printing/one-side printing information exists, in step S 605 , the saving ratio calculation module  1031   e  judges whether or double-sided printing has been performed. If the double-sided printing has been performed, in step S 606 , the saving ratio calculation module  1031   e  further multiplexes the number of logical pages calculated by the above-described processing by two to thereby calculate the number of logical pages. In addition, the saving ratio calculation module  1031   e  calculates the number of physical pages by multiplying the number of physical sheets by two. If the information indicating double/one sided printing mode does not exist, or if the double-sided printing has not been performed, in step S 607 , the saving ratio calculation module  1031   e  regards the number of physical sheets as the number of physical pages directly. 
   Then, in step S 608 , the saving ratio calculation module  1031   e  substitutes the number of logical pages, the number of physical pages, and the number of physical sheets calculated in the above-described processing in the expression [page saving ratio=(number of logical pages−number of physical pages)/number of logical pages] to thereby calculate a page saving ratio. In addition, in step S 609 , the saving ratio calculation module  1031   e  substitutes the number of logical pages, the number of physical pages, and the number of physical sheets calculated in the above-described processing in the expression [number of sheets saving ratio=(number of logical pages−number of logical sheets)/number of logical pages] to thereby calculate a number of sheets saving ratio. 
   Note that in the case in which the number of physical pages is included in the print information, it is sufficient to substitute the number of physical pages for the number of logical pages in step S 603 , and substitute the number of physical pages×Nup number for the number of logical pages in step S 602 . In this case, the processing of steps S 604  to S 607  is unnecessary. 
   (Saving Ratio Calculation from Job Information and Print Information) 
   Next, processing for saving ratio calculation, which is performed in step S 405 , will be described with reference to  FIG. 13 .  FIG. 13  is a flowchart showing processing for calculating a saving ratio from job information and print information. Here, it is assumed that at least the number of physical sheets is included in the print information. 
   In step S 701 , the saving ratio calculation module  1031   e  judges whether or not double-sided printing/one-side printing information exists in the print information. If the double-sided printing/one-side printing exists, in step S 702 , the saving ratio calculation module  1031   e  judges whether or not double-sided printing has been performed. If the double-sided printing has been performed, in step S 703 , the saving ratio calculation module  1031   e  multiplies the number of physical sheets by two to thereby calculate the number of physical pages. If the double-sided printing/one-side printing information does not exist, or if the double-sided printing has not been performed, in step S 704 , the saving ratio calculation module  1031   e  regards the number of physical sheets as the number of physical pages directly. 
   Then, in step S 705 , the saving ratio calculation module  1031   e  substitutes the number of logical pages, the number of physical pages, and the number of physical sheets calculated in the above-described processing in the expression [page saving ratio=(number of logical pages−number of physical pages)/number of logical pages] to thereby calculate a page saving ratio. In addition, in step S 706 , the saving ratio calculation module  1031   e  substitutes the number of logical pages, the number of physical pages, and the number of physical sheets calculated in the above-described processing in the expression [number of sheets saving ratio=(number of logical pages−number of logical sheets)/number of logical pages] to thereby calculate a number of sheets saving ratio. 
   Note that, in the case in which both the number of physical sheets and the number of physical pages are included in the print information, the processing of steps S 701  to S 704  are unnecessary. 
   According to the above-described embodiment, it is possible to acquire not only the number of logical pages but also information relating to saving such as a page layout and double-sided printing from the job information to increase a saving ratio. 
   In addition, even in an environment in which such information cannot be acquired at the time of print request, it is possible to acquire the actual number of outputted sheets from the apparatus and acquire information relating to saving such as a page layout and double-sided printing included in the print information from the apparatus to calculate a saving ratio. 
   Further, even in the case in which information relating to saving such as a page layout and double-sided printing cannot be acquired, it is possible to acquire the number of logical pages from the client computer and acquire the number of outputted pages and the number of sheets from the apparatus, and uses the number of logical pages, the number of outputted pages, and the number of sheets to thereby calculate a saving ratio. 
   Moreover, it is possible to judge presence or absence of these pieces of information and automatically switch a calculation method of a saving ratio to thereby calculate a saving ratio efficiently in any environment or apparatus. 
   Other Embodiments 
   The embodiment of the present invention has been described in detail. The present invention may be applied to a system comprising plural apparatuses or may be applied to an apparatus comprising one device. 
   In addition, although a saving ratio is calculated as usage efficiency information in the above description, usage efficiency may be indicated by other numerical values. For example, it is also possible to calculate a page usage ratio according to [page usage ratio=number of physical pages/number of logical pages], calculate a number of sheets usage ratio according to [number of sheets usage ratio=number of physical sheets/number of logical pages], and output these usage ratios as the usage ratio information. Further, it is also possible to simply calculate the reduced number of pages according to [reduced number of pages=number of logical pages−number of physical pages], calculate reduced number of sheets according to [reduced number of sheets=number of logical pages−number of physical pages], and output these reduced numbers as the usage efficiency information. 
   Note that the present invention also includes a case in which the present invention is attained by supplying a program of software realizing the function of the above-described embodiment to a system or an apparatus directly or from a distant location, and a computer of the system or the apparatus reading out to execute a supplied program code. In that case, a form the software needs not be the program as long as it has a function of the program. 
   Therefore, a program code itself to be installed in a computer in order to realize the functional processing of the present invention with the computer also realizes the present invention. That is, the present invention includes a computer program itself for realizing the functional processing of the present invention. 
   In that case, the program may be in any form such as an object code, a program to be executed by an interpreter, a script data to be supplied to an OS, or the like as long as it has a function of the program. 
   As a recording medium for supplying a program, for example, there are a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, an MO, a CD-ROM, a CD-R, a CD-RW, a magnetic tape, a nonvolatile memory card, a ROM, and a DVD (DVD-ROM, DVD-R). 
   Besides, a program can also be supplied by making connection to a web page on the Internet using a browser of a client computer and downloading a computer program itself of the present invention or a file, which is compressed and includes an automatic installation function, to a recording medium such as a hard disk from the web page. In addition, the functional processing of the present invention can also be realized by dividing a program code constituting a program of the present invention into plural files and downloading the respective files from different web pages. That is, a WWW server, which downloads a program file for realizing the functional processing of the present invention with a computer to plural users, is also included in the present invention. 
   In addition, the functional processing of the present invention can also be realized by encrypting the program of the present invention and store the program in a storage medium such as a CD-ROM to distribute it to users, causing users who has cleared predetermined conditions to down load key information solving the encryption from the web page via the Internet, and executing the encrypted program by using the key information to cause the computer to install the program. 
   Further, the function of the embodiment can be realized by a computer executing a read out program. Besides, an OS or the like running on the computer performs a part or all of actual processing on the basis of an instruction of the program, and the function of the embodiment can be realized by the processing. 
   Moreover, a program read out from a recording medium is written in a memory provided in a function extended board inserted in a computer or a function extended unit connected to the computer, and then, a CPU or the like provided in the function extended board or the function extended unit performs a part or all of actual processing on the basis of an instruction of the program, and the function of the embodiment is realized by the processing. 
   According to the above-described embodiments, it becomes possible to grasp a usage ratio of an image forming apparatus. There is an effect that understanding for resource saving and energy saving is improved by managing a system on the basis of this information, and an efficient apparatus using environment can be realized. 
   As many apparently widely different embodiments of the present invention can be made without departing from the spirit and scope thereof, it is to be understood that the invention is not limited to the specific embodiments thereof except as defined in the appended claims.