Abstract:
An output system includes a user terminal including a first processor; an information processing system including one or more second processors; and one or more output apparatuses each including a third processor, wherein the first processor is configured to receive an output request from a user, an output request designating an output target data and an output destination selected from among the one or more output apparatuses, and send, in response to receiving the output request, the output target data to the information processing system and an acquisition request of outputting to the designated output apparatus and wherein the third processor is configured to execute, in response to receiving the acquisition request from the user terminal, an acquisition process to acquire the designated output target data from the information processing system.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation application of U.S. patent application Ser. No. 13/632,367 filed on Oct. 1, 2012, which claims the benefit of priority of Japanese Priority Application No. 2011-229742 filed on Oct. 19, 2011, the entire contents of which are hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a technique of controlling printing. 
         [0004]    2. Description of the Related Art 
         [0005]    In Patent Document 1, for example, a technique in which a server receives application data from a portable terminal, converts the application data to print data capable of being printed by rendering, and sends the converted print data to a printer is disclosed. As described above, a print control system of a push type printing is known. 
         [0006]    In the above print control system, the server is connected to an internal network such as an internal Local Area Network (LAN) or the like. In other words, in the above print control system, the portable terminal, the server, and the printer are connected with each other in a private environment. However, recently, a wide area print service has been developed in which a server is connected to an external network such as the INTERNET or the like so that application data to be converted by the server is accepted via the external network and converted print data is also sent to a printer via the external network. 
         [0007]    When a server connected to the external network is used to convert the application data, according to the conventional method as described above, there may be a problem as follows. Generally, there is provided a firewall between an internal network and an external network in a view of security. In such a case, the server connected to the external network cannot send the converted print data to a printer connected to an internal network. It means that according to the conventional method, a push type printing cannot be performed using a server provided in a public environment. 
       PATENT DOCUMENT 
     [Patent Document 1] Japanese Laid-open Patent Publication No. 2001-290742 
     SUMMARY OF THE INVENTION 
       [0008]    The present invention is made in light of the above problems, and provides a technique of controlling printing by which a push type printing can be performed using a data conversion apparatus connected to an external network. 
         [0009]    According to an embodiment, there is provided a print control system including a data conversion apparatus including a data conversion unit that converts application data to print data; an image processing apparatus including a print control unit that prints print data; and a data processing apparatus including a data conversion request unit that sends conversion request data including application data to be processed to the data conversion apparatus for requesting the converting of the application data to print data, and a print request unit that sends print request data including converting apparatus data indicating a data conversion apparatus from which print data to print is to be obtained to the image processing apparatus for requesting the obtaining of the converted print data from the indicated data conversion apparatus and printing the obtained print data. 
         [0010]    According to another embodiment, there is provided a method of controlling printing used in a print control system including a data conversion apparatus that converts application data to print data, an image processing apparatus that prints print data, and a data processing apparatus including a data conversion requesting step, performed by the data processing apparatus, of sending conversion request data including application data to be processed to the data conversion apparatus for requesting the converting of the application data to print data, and a print requesting step, performed by the data processing apparatus, of sending print request data including converting apparatus data indicating a data conversion apparatus from which print data to print is to be obtained to the image processing apparatus for requesting the obtaining of the print data converted by the indicated data conversion apparatus and printing the obtained print data. 
         [0011]    According to another embodiment, there is provided a non-transitory computer-readable recording medium having recorded thereon a program that causes a computer connected to a data conversion apparatus that converts application data to print data and an image processing apparatus that prints print data to execute a method of controlling printing, including a data conversion requesting step, performed by the data processing apparatus, of sending conversion request data including application data to be processed to the data conversion apparatus for requesting the converting of the application data to print data, and a print requesting step, performed by the data processing apparatus, of sending print request data including converting apparatus data indicating a data conversion apparatus from which print data to print is to be obtained to the image processing apparatus for requesting the obtaining of the print data converted by the indicated data conversion apparatus and printing the obtained print data. 
         [0012]    Note that also arbitrary combinations of the above-described constituents, and any exchanges of expressions in the present invention, made among method, device, system, recording medium, computer program and so forth, are valid as embodiments of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings. 
           [0014]      FIG. 1  is a view showing an example of a structure of a print control system of an embodiment; 
           [0015]      FIG. 2  is a view showing an example of an operation of a print service provided by the print control system; 
           [0016]      FIG. 3  is a block diagram showing an example of a hardware structure of a data processing apparatus of the embodiment; 
           [0017]      FIG. 4  is a block diagram showing an example of the print control function of the embodiment; 
           [0018]      FIG. 5  is a view showing an example of conversion request data of the embodiment; 
           [0019]      FIG. 6  is a view showing an example of print request data of the embodiment; 
           [0020]      FIG. 7  is a view showing an example of management information of the embodiment; 
           [0021]      FIG. 8  is a view showing an example of control information of the embodiment; 
           [0022]      FIG. 9  is a sequence diagram showing an example of an operation of print control of the embodiment; 
           [0023]      FIG. 10  is a view showing another example of the conversion request data; 
           [0024]      FIG. 11  is a view showing an example of a spooling operation of the example; 
           [0025]      FIG. 12  is a block diagram showing an example of the print control function of the embodiment; 
           [0026]      FIG. 13A  is a view showing an example of conversion request data TRD of the embodiment 
           [0027]      FIG. 13B  is a view showing an example of job ID notification data of the embodiment; 
           [0028]      FIG. 14  is a sequence diagram showing an example of an operation of print control of the embodiment; 
           [0029]      FIG. 15  is a block diagram showing an example of the print control function of the embodiment; 
           [0030]      FIG. 16A  is a view showing an example of conversion request data of the embodiment; 
           [0031]      FIG. 16B  is a view showing an example of job ID-predicted time notification data of the embodiment; 
           [0032]      FIG. 17  is a view showing an example of calculation data for calculating a predicted time; 
           [0033]      FIG. 18  is a view showing an example of print request data of the embodiment; 
           [0034]      FIG. 19  is a sequence diagram showing an example of an operation of print control of the embodiment; 
           [0035]      FIG. 20  is a block diagram showing an example of the print control function of the embodiment; and 
           [0036]      FIG. 21  is a sequence diagram showing an example of an operation of print control of the embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0037]    The invention will be described herein with reference to illustrative embodiments. Those skilled in the art will recognize that many alternative embodiments can be accomplished using the teachings of the present invention and that the invention is not limited to the embodiments illustrated for explanatory purposes. 
         [0038]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
       First Embodiment 
     System Structure 
       [0039]      FIG. 1  is a view showing an example of a structure of a print control system  1  of the embodiment. 
         [0040]    The print control system  1  shown in  FIG. 1  includes one or more data processing apparatuses  100   1  to  100   n  (each of which is simply referred to as a “data processing apparatus  100 ” as well), one or more image processing apparatuses  300   1  to  300   n  (each of which is simply referred to as an “image processing apparatus  300 ” as well), and one or more data conversion apparatuses  200 . The data processing apparatuses  100   1  to  100   n  and the image processing apparatuses  300   1  to  300   n  are respectively connected to an internal network N. The data conversion apparatuses  200  are connected to an external network I which is connected to the internal networks N via the firewalls FW, respectively. It means that the data processing apparatuses and the image processing apparatuses  300  are secured by the firewalls FW, with respect to the data conversion apparatuses  200 . 
         [0041]    The data processing apparatus  100  has a data processing function and is a user terminal such as a Personal Computer (PC) or the like. The image processing apparatus  300  has an image processing function including a printing function. The image processing apparatus  300  may be a printer, a Multifunction Peripheral (MFP) or the like. 
         [0042]    The data conversion apparatus  200  has a data conversion function of converting data received from the data processing apparatus  100  to print data capable of being printed by the image processing apparatus  300 . The data conversion apparatus  200  is a rendering server or the like. 
         [0043]    The print control system  1  of the embodiment provides the print service as shown in  FIG. 2 , for example.  FIG. 2  is a view showing an example of an operation of a print service provided by the print control system  1 . 
         [0044]    The data processing apparatus  100  accepts selections of application data to be processed and a data conversion apparatus  200  by a user via an operation panel or the like and sends a request of converting application data to print data with the application data to the selected one of the data conversion apparatuses  200 . Then, the data conversion apparatus  200  converts the received application data to print data. Further, upon accepting the selection of the application data to be processed, the data processing apparatus  100  sends a request of printing the print data converted by the selected data conversion apparatus  200  data with data indicating the selected data conversion apparatus  200 , to a selected one of the image processing apparatuses  300 . Then, upon receiving the request of printing, the selected image processing apparatus  300  sends a request of sending the converted print data, to the data conversion apparatus  200  specified by the data indicating the selected data conversion apparatus  200 . Subsequently, when the print data is obtained from the selected data conversion apparatus  200 , the image processing apparatus  300  prints the print data sent from the selected data conversion apparatus  200 . 
         [0045]    At this time, the data conversion apparatus  200  to convert and the image processing apparatus  300  to print may be automatically selected by the data processing apparatus  100 , a functional component of the print control system  1  or the like. 
         [0046]    As described above, according to the print control system  1  of the embodiment, a print service capable of performing a push type printing using the data conversion apparatus  200  connected to the external network I is provided. 
         [0047]    Further, in this embodiment, as described above, the data processing apparatus  100  can use the print service by just sending the application data, not the print data. Thus, it is not necessary for the data processing apparatus  100  to have a function of converting application data to print data, such as is performed by a printer driver. Specifically, the data processing apparatus  100  may be a Smartphone, a tablet PC, a projector, a media board or the like. 
       (Hardware Structure) 
       [0048]      FIG. 3  is a block diagram showing an example of a hardware structure of the data processing apparatus  100  of the embodiment. 
         [0049]    As shown in  FIG. 3 , the data processing apparatus  100  includes an input device  101 , a display device  102 , an external interface (I/F)  103 , a Random Access Memory (RAM)  104 , a Read-Only Memory (ROM)  105 , a Central Processing Unit (CPU)  106 , a communication interface (I/F)  107 , a Hard Disk Drive (HDD)  108  and the like, which are connected with each other via a BUS B. 
         [0050]    The input device  101  includes a keyboard, a mouse or the like and is used for inputting various operational signals into the data processing apparatus  100 . The display device  102  includes a display or the like and displays a result processed by the data processing apparatus  100 . 
         [0051]    The communication I/F  107  connects the data processing apparatus  100  to a network such as the internal networks N shown in  FIG. 1 . With the function of the communication I/F  107 , the data processing apparatus  100  is capable of communicating with other apparatuses such as the data conversion apparatus  200 , the image processing apparatus  300  or the like via the communication I/F  107 . 
         [0052]    The HDD  108  is a nonvolatile storage device storing programs or data. The programs or data stored in the HDD  108  may be an Operating System (OS) which is basic software controlling the entirety of the apparatus, application software providing various functions on the OS, or the like. The HDD  108  manages the programs or data stored therein by a predetermined file system and/or a Database (DB). 
         [0053]    The external I/F  103  is an interface for an external device such as a recording medium  103   a  or the like. With the function of the external I/F  103 , the data processing apparatus  100  is capable of reading and/or writing data in the recording medium  103   a  via the external I/F  103 . The recording medium  103   a  may be a floppy (registered trademark) disk, a Compact Disk (CD), a Digital Versatile Disk (DVD), an SD memory card, a Universal Serial Bus memory (USB memory) or the like. 
         [0054]    The ROM  105  is a nonvolatile semiconductor memory (storage device) capable of storing data even when power is switched off. The ROM  105  stores Basic Input/Output System (BIOS) which is executed when initiating the data processing apparatus  100 , program or data for setting the OS or network, or the like. The RAM  104  is a volatile semiconductor memory (storage device) temporarily storing programs or data. The CPU  106  is an arithmetic unit which reads out the programs or data from the storage devices such as the HDD  108 , the ROM  105  or the like on the RAM  104  and actualizes controlling of the entirety of the apparatus and functions on the apparatus. 
         [0055]    As described above, according to the data processing apparatus  100  of the embodiment, various processing services including controlling printing, with the above hardware structure. 
         [0056]    Although not shown in the drawings, each of the data conversion apparatuses  200  and each of the image processing apparatuses  300  have the same hardware structures as explained above with reference to  FIG. 3 . 
       (Print Control Function) 
       [0057]    The print control function of the embodiment is explained. 
         [0058]    In the print control system  1  of the embodiment, the data processing apparatus  100  connected to the internal network N sends conversion request data including application data to be processed, to the data conversion apparatus  200  connected to the external network I for requesting a conversion of the application data to print data. Upon receiving the conversion request data, the data conversion apparatus  200  converts the received application data to print data. 
         [0059]    Further, the data processing apparatus  100  sends print request data including an indication of one of the data conversion apparatuses  200  selected to convert the application data and from which the image processing apparatus  300  is to obtain the converted print data, to one of the image processing apparatuses  300  connected to the internal network N and selected to print for requesting the printing. Upon receiving the print request data, the image processing apparatus  300  requests sending the print data to the data conversion apparatus  200  selected to convert the application data. Then, upon receiving the print data, the image processing apparatus  300  prints the print data. The print control system  1  of the embodiment has such a print control function. 
         [0060]    According to the conventional system, a following problem may occur. In the internal network N, internal addresses of apparatuses may be masked by a router so that it may be difficult to determine the addresses within the firewall FW (see  FIG. 1 ) from the external network I. Further, even when an apparatus can be specified by a public address, the external access may be blocked by the firewall FW. Thus, in the conventional system, a push type printing cannot be performed as it is difficult to send converted print data from a data conversion apparatus connected to the external network I to an image processing apparatus connected to the internal network N because of the firewall FW. 
         [0061]    Thus, in the print control system  1  of the embodiment, the data processing apparatus  100  is configured to send a request of obtaining print data from the selected data conversion apparatus  200  and printing the obtained print data to the image processing apparatus  300  selected to print, in addition to sending a request of converting application data to print data to the selected data conversion apparatus  200 . 
         [0062]    With this, the print control system  1  of the embodiment provides an environment in which the image processing apparatus  300  selected to print is capable of dynamically obtaining the print data from the data conversion apparatus  200  and printing the obtained print data. Thus, according to the print control system  1  of the embodiment, it is not necessary for a user to perform a pull type printing as follows. 
         [0063]    In the pull type printing, for example, it is necessary for a user to first send a request of converting application data to print data, to the selected data conversion apparatus  200 . Then, it is necessary for the user to move to the image processing apparatus  300 , select the print data converted by the data conversion apparatus  200  to be obtained from the data conversion apparatus  200  and instruct to print the obtained print data at the image processing apparatus  300 . 
         [0064]    According to the print control system  1  of the embodiment, a pseudo-push type printing can be performed using the data conversion apparatus  200  connected to the external network I. 
         [0065]    The print control function of the embodiment is explained. 
         [0066]      FIG. 4  is a block diagram showing an example of the print control function of the embodiment. 
         [0067]    As shown in  FIG. 4 , the data processing apparatus  100  of the embodiment includes a data conversion request unit  11 , a printer information obtaining unit  12 , a print request unit  13  and the like as the print control function. 
         [0068]    The data conversion apparatus  200  includes a data conversion request receiving unit  21 , a data conversion unit  22 , a print data sending unit  23  and the like as the print control function. The data conversion apparatus  200  further includes a management information storing unit  90 . 
         [0069]    The image processing apparatus  300  includes a print request receiving unit  31 , a print data obtaining unit  32 , a print control unit  33  and the like as the print control function. The image processing apparatus  300  further includes a control information storing unit  80 . 
         [0070]    As described above, the print control function of the embodiment is actualized by a combination of the components. 
       (Data Processing Apparatus  100 ) 
       [0071]    The data conversion request unit  11  requests a data conversion to the data conversion apparatus  200 . The data conversion request unit  11  sends conversion request data including application data to be processed for requesting a conversion of the application data to print data, to the data conversion apparatus  200 . 
         [0072]    The conversion request data sent by the data conversion request unit  11  is explained. 
         [0073]      FIG. 5  is a view showing an example of conversion request data TRD of the embodiment. As shown in  FIG. 5 , the conversion request data TRD includes data corresponding to items such as “conversion format”, “job ID”, “printer ID” or the like, in addition to the application data, although the application data is not shown in  FIG. 5 . 
         [0074]    Data corresponding to the item “conversion format” (hereinafter simply referred to as “conversion format data”) indicates a conversion format (a data format) of print data to be generated. The conversion format data may be an identifier of Page Description language (PDL) (PDL name, for example, hereinafter simply referred to as a “PDL identifier”) or the like. 
         [0075]    Data corresponding to the item “job ID” (hereinafter simply referred to as “job ID data”) is a value for identifying the application data (a job) to be processed. The job ID data may be an identifier uniquely allocated to the application data. 
         [0076]    Data corresponding to the item “printer ID” (hereinafter simply referred to as “printer ID data”) is a value for identifying the image processing apparatus  300  selected to print. The printer ID data may be an identifier uniquely allocated to the image processing apparatus  300  such as printer ID, Internet Protocol Address (IP address) or the like, for example. 
         [0077]    Referring back to  FIG. 4 , the data conversion request unit  11  displays an operation panel for accepting a selection of application data to be processed and a selection of one of the image processing apparatuses  300  to print. When a user selects application data (job) to be processed and the image processing apparatus  300  to print via the operation panel, the data conversion request unit  11  accepts the selections. Then, the data conversion request unit  11  generates the conversion request data TRD. At this time, the data conversion request unit  11  issues unique job ID data for the selected application data. Further, the data conversion request unit  11  obtains printer information including printer ID data of the selected image processing apparatus  300  to print and conversion format data from the printer information obtaining unit  12 , as will be explained later. 
         [0078]    With this, the data conversion request unit  11  generates the conversion request data TRD including the application data, the job ID data, the printer ID data, and the conversion format data. Then, the data conversion request unit  11  sends the generated conversion request data TRD to the data conversion apparatus  200 . 
         [0079]    Here, before sending the conversion request data TRD, the data conversion request unit  11  may determine whether the data conversion apparatus  200  is capable of converting the application data to be processed to the print data. Then, the data conversion request unit  11  may send the conversion request data TRD to the data conversion apparatus  200  when it is determined that the data conversion apparatus  200  is capable of converting the application data to the print data. At this time, the data conversion request unit  11  may determine whether the data conversion apparatus  200  is capable of converting the application data to the print data based on an extension of the application data such that whether the extension of the application data matches the extensions of data capable of being converted by the data conversion apparatus  200 . 
         [0080]    Further, when there are plural data conversion apparatuses  200  existing, the data conversion request unit  11  may automatically select one of the data conversion apparatuses  200  to send the conversion request data TRD. 
         [0081]    The printer information obtaining unit  12  obtains printer information. The printer information may be obtained by a two-way communication of a printer driver, or may be obtained from a registry of the OS, for example. The printer information includes the printer ID data, the conversion format data such as the PDL identifier which is adaptable for the corresponding image processing apparatus, or the like. The printer information obtaining unit  12  obtains printer information of the image processing apparatus  300  selected to print via the operation panel, and stores the obtained printer information in the predetermined storage area. 
         [0082]    Here, when the data conversion request unit  11  cannot obtain sufficient data such as the printer ID data, the conversion format data or the like from the printer information, the data conversion request unit  11  may display an operation panel capable of inputting or selecting the insufficient data, and may accept input or selection by the user. At this time, the operation panel may include information formed based on a configuration file in which default values for the corresponding items are set, for example. Then, the accepted values may be stored in the configuration file. The default values of the conversion format data in the configuration file may include a value indicating the conversion format capable of being converted by the data conversion apparatus  200 , conversion format adaptable for an environment in which the image processing apparatus  300  is placed, or the like. 
         [0083]    The print request unit  13  requests printing to the image processing apparatus  300 . The print request unit  13  sends print request data including information indicating the data conversion apparatuses  200  selected to convert the application data and from which the image processing apparatus  300  is to obtain the converted print data, to the image processing apparatus  300  selected to print among the image processing apparatuses  300  connected to the internal network N. 
         [0084]    The print request data is explained. 
         [0085]      FIG. 6  is a view showing an example of print request data PRD of the embodiment. As shown in  FIG. 6 , the print request data PRD includes data corresponding to items such as the “job ID”, “converting apparatus” or the like. 
         [0086]    Data corresponding to the item “job ID” (job ID data) is the value for identifying the application data (a job) to be processed for which the data conversion request unit  11  requests converting to print data the conversion to the print data. It means that the job ID data in the print request data PRD is identification of print data to obtain for the image processing apparatus  300 . 
         [0087]    Data corresponding to the item “converting apparatus” (hereinafter simply referred to as “converting apparatus data”) is a value indicating the data conversion apparatus  200  selected to convert to which the data conversion request unit  11  requests converting to print data. The converting apparatus data may be an access path to the data conversion apparatus  200  (“Uniform Resource Identifier (URI), for example). It means that the converting apparatus data in the print request data PRD is information about the data conversion apparatus  200  to obtain the print data for the image processing apparatus  300 . 
         [0088]    Referring back to  FIG. 4 , the print request unit  13  receives the data corresponding to the items from the data conversion request unit  11 , generates the print request data PRD including the converting apparatus data based on the received data, and sends the print request data PRD to the image processing apparatus  300  selected to print. 
         [0089]    As described above, the data processing apparatus  100  requests obtaining the print data and printing the obtained print data to the image processing apparatus  300  selected to print as well as requesting converting to the print data to the data conversion apparatus  200 . 
       (Data Conversion Apparatus  200 ) 
       [0090]    The data conversion request receiving unit  21  receives the request of converting application data to print data from the data processing apparatus  100 . Specifically, the data conversion request receiving unit  21  receives the conversion request data TRD including the application data sent from the data conversion request unit  11  of the data processing apparatus  100 . 
         [0091]    The data conversion unit  22  converts the received application data to print data. The data conversion unit  22  specifies a conversion format (a data format) for the print data based on the conversion format data included in the conversion request data TRD, and converts the application data to the print data (PDL data, for example) of the specified conversion format. The data conversion unit  22  stores the converted print data in a predetermined storage area in a storing device of the data conversion apparatus  200 . 
         [0092]    The conversion request data TRD received by the data conversion request receiving unit  21  and the print data converted by the data conversion unit  22  are managed in the data conversion apparatus  200  based on management information as shown in  FIG. 7 , for example. 
         [0093]    The management information is explained.  FIG. 7  is a view showing an example of management information  90 D of the embodiment. 
         [0094]    As shown in  FIG. 7 , the management information  90 D includes one or more data sets in each of which the job ID, the printer ID, an access path, a status and the like are corresponded with each other. The data set is prepared for each of the received request of converting application data to print data. 
         [0095]    The job ID data in the conversion request data TRD is stored in the item “job ID”. The printer ID data in the conversion request data TRD is stored in the item “printer ID”. 
         [0096]    The item “access path” stores information indicating an access path to the print data (storage area at which the print data is stored, hereinafter referred to as “access path data”). 
         [0097]    The item “status” stores a status of a data conversion (hereinafter referred to as “status information”). The status may be “start conversion”, “converting”, “converted (completed)” or the like. 
         [0098]    These data corresponding to the items are stored in the management information storing unit  90 . 
         [0099]    These data corresponding to the items are stored and updated by the data conversion request receiving unit  21  and the data conversion unit  22 . 
         [0100]    The data conversion request receiving unit  21  accesses the management information storing unit  90 , and generates the data set for the received conversion request data TRD by registering the job ID data and the printer ID data included in the received conversion request data TRD for the item “job ID” and the item “printer ID”, respectively. 
         [0101]    The data conversion unit  22  records the status of the data conversion for the item “status” of the corresponding data set generated by the data conversion request receiving unit  21 , and further updates the status in accordance with the progress of the data conversion. When the data conversion is completed and the converted print data is stored in the predetermined storage area in the storing device of the data conversion apparatus  200 , the data conversion unit  22  records an access path for the item “access path” of the corresponding data set generated. 
         [0102]    The print data sending unit  23  responds to a request of sending print data sent from the image processing apparatus  300 . Specifically, the print data sending unit  23  receives the request of sending print data of the application data to be processed identified by the job ID data received from the image processing apparatus  300 , and sends the status information or the print data. At this time, when the print data sending unit  23  receives the request from the image processing apparatus  300 , the print data sending unit  23  accesses the management information storing unit  90 , specifies the data set in the management information  90 D based on the received job ID data, and refers to the status information (or the access path data) of the specified data set. When the status information is “start conversion” or “converting”, the print data sending unit  23  sends a notice that the application data to be processed in the request of sending print data is now being converted to the image processing apparatus  300  in response. On the other hand, when the status information is “converted (completed)”, the print data sending unit  23  obtains the print data based on the access path data, and sends the obtained print data to the image processing apparatus  300  in response. 
         [0103]    As described above, the data conversion apparatus  200  converts the application data to be processed to the print data in accordance with the request of converting application data to print data from the data processing apparatus  100 , and sends the converted print data to the image processing apparatus  300  in accordance with the request of sending print data. 
       (Image Processing Apparatus  300 ) 
       [0104]    The print request receiving unit  31  receives a request of printing from the data processing apparatus  100 . The print request receiving unit  31  receives the print request data PRD including the converting apparatus data sent from the print request unit  13  of the data processing apparatus  100 . 
         [0105]    The print data obtaining unit  32  sends a request of sending print data to the data conversion apparatus  200 . Specifically, the print data obtaining unit  32  accesses the data conversion apparatus  200  based on the converting apparatus data included in the print request data PRD received by the print request receiving unit  31 , and sends a request command of sending print data including the job ID data of the application data to be processed included in the print request data PRD for requesting the sending of the print data. 
         [0106]    Then, in response to the request, the print data sending unit  23  of the data conversion apparatus  200  sends the status information or the print data to the print data obtaining unit  32 . When the status information is sent from the data conversion apparatus  200 , the print data obtaining unit  32  re-sends the request of sending print data after a predetermined period has passed and repeats this operation until the print data is sent from the data conversion apparatus  200 . This operation is controlled by control information as shown in  FIG. 8 , for example. 
         [0107]      FIG. 8  is a view showing an example of control information  80 D of the embodiment. As shown in  FIG. 8 , the control information  80 D includes control parameter values such as “inquiring time interval” indicating time interval for sending the request, “response time limit” indicating response time limit (time out) in response to the request or the like. The control information  80 D is stored in the control information storing unit  80 . 
         [0108]    The control information  80 D may be previously set in accordance with an operating policy of the provided print service by an administrator, for example. 
         [0109]    Referring back to  FIG. 4 , when sending the request, the print data obtaining unit  32  accesses the control information storing unit  80 , and controls communication with the data conversion apparatus  200  based on the response time limit set in the control information  80 D. Specifically, the print data obtaining unit  32  counts response time from the data conversion apparatus  200  by a timing circuit (not shown in the drawings) of the image processing apparatus  300 , performs a predetermined error operation when the counted value exceeds the set response time limit and then completes sending the request. When the status information is sent from the data conversion apparatus  200 , the print data obtaining unit  32  controls inquiring to the data conversion apparatus  200  based on the inquiring time interval set in the control information  80 D. Specifically, the print data obtaining unit  32  repeats inquiring to the data conversion apparatus  200  with the set inquiring time interval. 
         [0110]    The print control unit  33  controls printing. The print control unit  33  prints the print data obtained by the print data obtaining unit  32 . Specifically, the print control unit  33  sends the print data to a plotter (not shown in the drawings) included in the image processing apparatus  300 , and controls printing by the plotter in accordance with a predetermined printing condition. 
         [0111]    As described above, the image processing apparatus  300  requests sending the print data which is converted from the application data to be processed, to the data conversion apparatus  200  in response to a request of printing from the data processing apparatus  100 , and prints the obtained print data. 
         [0112]    As described above, the print control function of the embodiment is actualized by a combination of the components. Further, the above functional components are actualized when arithmetic units (CPUs) read programs installed in the apparatuses or devices composing the print control system  1  from the storage devices (HDDs or ROMs) on the memories (RAMs), respectively. 
         [0113]    The operation of the print control function of the embodiment is explained in detail with respect to a sequence diagram. 
         [0114]      FIG. 9  is a sequence diagram showing an example of an operation of print control of the embodiment. 
       (Operation by Data Processing Apparatus  100 ) 
       [0115]    Upon an instruction from the user, the data conversion request unit  11  displays an operation panel and accepts selections of application data to be processed and the image processing apparatus  300  to print the selected application data. At this time, the data conversion request unit  11  issues job ID data for the application data to be processed. 
         [0116]    Then, the data conversion request unit  11  indicates the printer information obtaining unit  12  to obtain the printer information of the selected image processing apparatus  300  (step S 101 ). 
         [0117]    When the printer information obtaining unit  12  obtains the printer information, the data conversion request unit  11  refers to the printer information obtained by the printer information obtaining unit  12  (step S 102 ). Then, the data conversion request unit  11  generates the conversion request data TRD including the selected application data, the job ID data, and the conversion format data and the printer ID data obtained from the printer information of the selected image processing apparatus  300  (step S 103 ). The data conversion request unit  11  sends the conversion request data TRD for requesting a conversion of the application data to print data, to the data conversion apparatus  200  (step S 104 ). 
         [0118]    Further, the data conversion request unit  11  indicates the print request unit  13  to send a request of printing (step S 107 ). At this time, the data conversion request unit  11  outputs the job ID data and the converting apparatus data to the print request unit  13 . Then, the print request unit  13  generates the print request data PRD including the job ID data and the converting apparatus data (step S 108 ). The print request unit  13  sends the print request data PRD for requesting the obtaining of the print data and printing the obtained print data, to the image processing apparatus  300  (step S 109 ). 
       (Operation by Data Conversion Apparatus  200 ) 
       [0119]    When the data conversion apparatus  200  receives the conversion request data TRD from the data processing apparatus  100 , the data conversion request receiving unit  21  indicates the data conversion unit  22  to convert the received application data to print data (step S 201 ). At this time, the data conversion request receiving unit  21  outputs the application data, the conversion format data, the job ID data, and the printer ID data included in the conversion request data TRD to the data conversion unit  22 . 
         [0120]    Further, at this time, the data conversion request receiving unit  21  accesses the management information storing unit  90 , records the job ID data and the printer ID data included in the received conversion request data TRD as values for the items “job ID” and “printer ID” respectively, and generates a data set of the management information  90 D for the received conversion request data TRD. 
         [0121]    Then, the data conversion unit  22  starts converting the application data to print data (step S 202 ). At this time, the data conversion unit  22  converts the application data to print data of the conversion format specified by the conversion format data. Meanwhile, the data conversion unit  22  records the status of the conversion “start conversion” or “converting” for the item “status” in the data set of the management information  90 D generated by the data conversion request receiving unit  21 . The data conversion unit  22  may periodically update the status of the conversion in accordance with the operation. 
         [0122]    The data conversion unit  22  indicates the print data sending unit  23  to wait for a request of sending print data from the image processing apparatus  300  (step S 203 ). At this time, the data conversion unit  22  outputs the printer ID data to the print data sending unit  23 . 
         [0123]    Then, the print data sending unit  23  starts waiting for the request of sending print data from the image processing apparatus  300  identified by the printer ID data (step S 204 ). When the print data sending unit  23  receives the request of sending print data from the identified image processing apparatus  300 , the print data sending unit  23  accesses the management information storing unit  90 , and refers to the status information of the management information  90 D specified by the received job ID data. When the status information is “start conversion” or “converting”, the print data sending unit  23  responds to the image processing apparatus  300  which has sent the request that the application data to be processed specified by the request is now being converted. When the status information is “converted (completed)”, the print data sending unit  23  obtains the converted and stored print data based on the access path data, and sends the converted print data converted from the application to be processed specified by the job ID data included in the request of sending print data, to the image processing apparatus  300 . 
       (Operation by Image Processing Apparatus  300 ) 
       [0124]    When the image processing apparatus  300  receives the request of obtaining the print data and printing the obtained print data from the data processing apparatus  100 , the print request receiving unit  31  indicates the print data obtaining unit  32  to send the request of sending print data (step S 301 ). At this time, the print request receiving unit  31  outputs the job ID data and the converting apparatus data included in the received print request data PRD to the print data obtaining unit  32 . 
         [0125]    Then, the print data obtaining unit  32  sends the request of sending print data to the data conversion apparatus  200  (step S 302 ). At this time, the print data obtaining unit  32  accesses the data conversion apparatus  200  identified by the converting apparatus data, and sends the request of sending print data by sending the request command of sending print data of the application data to be processed including the job ID data (step S 4011 ). At this time, when the application data identified by the job ID data is being converted by the data conversion apparatus  200 , the fact that the application data is being converted is sent to the print data obtaining unit  32 , for example (step S 4012 ). 
         [0126]    Further at this time, the print data obtaining unit  32  accesses the control information storing unit  80  and controls communication with the data conversion apparatus  200  based on the response time limit set in the control information  80 D. Specifically, when the status information is sent from the data conversion apparatus  200 , the print data obtaining unit  32  repeats sending the request to the data conversion apparatus  200  with the inquiring time interval set in the control information  80 D, “300 (sec)”, for example. When there is no response from the data conversion apparatus  200  more than the response time limit set in the control information  80 D, “60 (sec)”, for example, the print data obtaining unit  32  performs the predetermined error operation (for example, sending an error notice to the data processing apparatus  100  which has sent the print request data PRD) and ends the operation of sending the request. 
       (Operation by Data Conversion Apparatus  200 ) 
       [0127]    When the data conversion unit  22  of the data conversion apparatus  200  completes the conversion of the application data to the print data, the data conversion unit  22  stores the print data in the predetermined storage area (step S 205 ). At this time, the data conversion unit  22  records the access path to the stored converted print data for the item “access path” of the management information  90 D. Further, the data conversion unit  22  updates the status of the conversion for the item “status” of the management information  90 D to “converted (completed)”. 
       (Operation by Image Processing Apparatus  300 ) 
       [0128]    At this time, when the print data obtaining unit  32  of the image processing apparatus  300  sends the request of sending print data to the data conversion apparatus  200  identified by the converting apparatus data (step S 4021 ), the converted print data is sent from the data conversion apparatus  200  (step S 4022 ). 
         [0129]    With this operation, the print data obtaining unit  32  ends sending the request of sending print data, and indicates the print control unit  33  to print the obtained print data (step S 303 ). At this time, the print data obtaining unit  32  outputs the received print data to the print control unit  33 . 
         [0130]    Then, the print control unit  33  outputs the print data to the plotter (not shown in the drawings) included in the image processing apparatus  300 , and performs printing in accordance with a predetermined printing condition (step S 304 ). 
         [0131]    As described above, according to the print control system  1  of the embodiment, the data processing apparatus  100  requests obtaining the print data and printing the obtained print data to the image processing apparatus  300  selected to print as well as requesting the converting of the application data to the print data to the data conversion apparatus  200 . 
         [0132]    Thus, the print control system  1  of the embodiment is capable of providing an environment in which the image processing apparatus  300  selected to print dynamically obtains the print data from the data conversion apparatus  200  to print the print data. 
         [0133]    Therefore, according to the print control system  1  of the embodiment, the data conversion request unit  11  of the data processing apparatus  100  connected to the internal network N sends the conversion request data TRD including the application data to be processed to the data conversion apparatus  200  connected to the external network I for requesting the converting of the application data to print data. Then, the data conversion unit  22  of the data conversion apparatus  200  converts the received application data to the print data. 
         [0134]    Further, the print request unit  13  of the data processing apparatus  100  sends the print request data PRD including the converting apparatus data to the image processing apparatus  300  selected to print connected to the internal network N for requesting the printing. Then, the image processing apparatus  300  sends a request of sending the print data to the data conversion apparatus  200  selected to convert by the print data obtaining unit  32  and prints the obtained print data by the print control unit  33 . 
         [0135]    With this, the print control system  1  of the embodiment is capable of providing an environment in which the image processing apparatus  300  selected to print dynamically obtains the print data from the data conversion apparatus  200 , and prints the obtained print data. Thus, it is possible to perform a pseudo-push type printing using the data conversion apparatus  200  connected to the external network I. 
       (Alternative Example) 
       [0136]    In the above embodiment, the data conversion apparatus  200  is configured to perform a data conversion of the application data to be processed received from the data processing apparatus  100  in a received order. 
         [0137]    In this example, the data processing apparatus  100  sends a request of converting application data to print data in which the order of data conversion is indicated, to the data conversion apparatus  200 . 
         [0138]    With this, according to the example, an environment in which the order of data conversion is controlled can be provided. 
         [0139]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
       (Print Control Function) 
       [0140]    In this example, functions of the data conversion request unit  11  of the data processing apparatus  100  and the data conversion unit  22  of the data conversion apparatus  200  are different from those of the above embodiment. 
       (Data Processing Apparatus  100 ) 
       [0141]    The data conversion request unit  11  sends the conversion request data TRD as shown in  FIG. 10 , for example, to the data conversion apparatus  200  for requesting a conversion of the application data to be processed to print data. 
         [0142]      FIG. 10  is a view showing another example of the conversion request data TRD. 
         [0143]    As shown in  FIG. 10 , the conversion request data TRD includes data corresponding to an item “priority” in addition to the conversion format data, the job ID data, the printer ID data or the like. 
         [0144]    Data corresponding to the item “priority” (hereinafter simply referred to as “priority data”) indicates a priority value by which the order of conversion is determined. The priority data may be a stepwise value indicating priority such as one of 1 to 5, for example. The priority data may be selected by the user via an operation panel. 
         [0145]    The data conversion request unit  11  displays an operation panel capable of inputting or selecting the priority data, generates the conversion request data TRD including the application data based on the priority data input or selected via the operation panel, and sends the conversion request data TRD to the data conversion apparatus  200 . 
         [0146]    With this, the data processing apparatus  100  of the embodiment sends the request of converting application data to print data in which the order of data conversion is indicated, to the data conversion apparatus  200 . 
       (Data Conversion Apparatus  200 ) 
       [0147]    When the data conversion request receiving unit  21  receives the request of converting application data to print data, the data conversion unit  22  controls a spooling operation in a data conversion as shown in  FIG. 11 , for example. 
         [0148]      FIG. 11  is a view showing an example of the spooling operation of the example. (A) of  FIG. 11  shows an example of the spooling operation in accordance with a received order. (B) of  FIG. 11  shows a spooling operation in accordance with an order of priority. 
         [0149]    As shown in (A), in the above embodiment, when the data conversion request receiving unit  21  receives the application data to be processed from the data processing apparatus  100 , the received application data to be processed are stored in a spooler in the received order and then, the application data to be processed are converted to corresponding print data in the stored order. Thus, the data conversion unit  22  performs the data conversion in accordance with “First In First Out (FIFO)”. 
         [0150]    In this example, as shown in (B), when the data conversion apparatus  200  receives the application data to be processed from the data processing apparatus  100 , the received application data to be processed are stored in the spooler in an order based on the priority data included in the conversion request data TRD. Then, the application data to be processed are converted to corresponding print data in the stored order. Thus, in this example, the received application data to be processed are sorted in the order based on the priority data included in the conversion request data TRD. As a result, the data conversion unit  22  converts the application data in an order of priority (sort order). 
         [0151]    As described above, in the data conversion apparatus  200  of the example, the order of converting the application data to be processed is controlled in accordance with a priority. 
       Second Embodiment 
       [0152]    In the print control system  1 , it is necessary to uniquely set the job ID data. Thus, in this embodiment, the job ID data are managed (allocated) at the data conversion apparatus  200  side. 
         [0153]    Thus, according to the embodiment, the data conversion apparatus  200  automatically issues job ID data when receiving the request of converting application data to print data, and sends the issued data job ID data to the processing apparatus  100 . 
         [0154]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
       (Print Control Function) 
       [0155]      FIG. 12  is a block diagram showing an example of the print control function of the embodiment. 
         [0156]    As shown in  FIG. 12 , in this embodiment, the data conversion unit  22  of the data conversion apparatus  200  includes a job ID issuing unit  211 . Further, in this embodiment, the functions of the data conversion request unit  11  and the print request unit  13  of the data processing apparatus  100  and the data conversion unit  22  of the data conversion apparatus  200  are different from those of the first embodiment. 
       (Data Processing Apparatus  100  and Data Conversion Apparatus  200 ) 
       [0157]    In the data processing apparatus  100 , the data conversion request unit  11  sends the conversion request data TRD as shown in  FIG. 13A , for example, to the data conversion apparatus  200  for requesting the converting to the print data. Then, in the data conversion apparatus  200 , upon receiving the request of converting application data to print data, the data conversion request receiving unit  21  issues job ID data for the received application data to be processed and sends the issued job ID to the data processing apparatus  100  in response. 
         [0158]      FIG. 13A  is a view showing an example of the conversion request data TRD of the embodiment. As shown in  FIG. 13A , the conversion request data TRD includes the conversion format data, the printer ID data or the like, but does not include the job ID data. 
         [0159]    Referring back to  FIG. 12 , in the data processing apparatus  100 , when a user selects application data (job) to be processed and the image processing apparatus  300  to print via the operation panel, the data conversion request unit  11  accepts the selections. At this time, the data conversion request unit  11  does not issue job ID data for the selected application data to be processed. The data conversion request unit  11  generates the conversion request data TRD including the selected application data, and sends the conversion request data TRD to the data conversion apparatus  200 . 
         [0160]    In the data conversion apparatus  200 , when the data conversion request receiving unit  21  receives the request of converting application data to print data, the job ID issuing unit  211  issues unique job ID data for the application data included in the received request of converting application data to print data. 
         [0161]      FIG. 13B  is a view showing an example of job ID notification data JRD. 
         [0162]    As shown in  FIG. 13B , the job ID notification data JRD includes the job ID data corresponding to the item “job ID”. The job ID data is a value issued by the job ID issuing unit  211  of the data conversion request receiving unit  21 . 
         [0163]    Referring back to  FIG. 12 , the data conversion request receiving unit  21  sends the job ID notification data JRD including the job ID data issued by the job ID issuing unit  211  to the data processing apparatus  100  as a reply. 
         [0164]    At this time, the data conversion request receiving unit  21  accesses the management information storing unit  90 , and generates the data set for the received conversion request data TRD by registering the job ID data issued by the job ID issuing unit  211  and the printer ID data included in the received conversion request data TRD for the item “job ID” and the item “printer ID”, respectively. 
         [0165]    Then, in the data processing apparatus  100 , the data conversion request unit  11  receives the job ID notification data JRD sent from the data conversion request receiving unit  21  of the data conversion apparatus  200 , outputs the job ID data included in the job ID notification data JRD to the print request unit  13  with the converting apparatus data and indicates the print request unit  13  to send a request of obtaining the print data and printing the obtained print data. 
         [0166]    As described above, in the print control system  1  of the embodiment, the data conversion apparatus  200  issues the job ID data when receiving the request of converting application data to print data from the data processing apparatus  100 , and replies the issued job ID data to the data processing apparatus  100  which has sent the request. 
         [0167]    As described above, the print control function of the embodiment is actualized by a combination of the components. 
         [0168]    The operation of the print control function of the embodiment is explained in detail with respect to a sequence diagram. 
         [0169]      FIG. 14  is a sequence diagram showing an example of an operation of print control of the embodiment. For the operation shown in  FIG. 14 , processes after step S 201  and processes after step S 301  are the same as those shown in  FIG. 9 , and thus the explanation is not repeated. Only steps S 101  to S 114  which are different from those shown in  FIG. 9  are explained. 
       (Operation by Data Processing Apparatus  100 ) 
       [0170]    As shown in  FIG. 14 , upon an instruction from the user, the data conversion request unit  11  of the data processing apparatus  100  displays an operation panel and accepts selections of application data to be processed and the image processing apparatus  300  to print the selected application data. Then, the data conversion request unit  11  indicates the printer information obtaining unit  12  to obtain the printer information of the selected image processing apparatus  300  (step S 101 ). When the printer information obtaining unit  12  obtains the printer information, the data conversion request unit  11  refers to the printer information obtained by the printer information obtaining unit  12  (step S 102 ). 
         [0171]    Then, the data conversion request unit  11  generates the conversion request data TRD including the selected application data, and the conversion format data and the printer ID data obtained from the printer information of the selected image processing apparatus  300  (step S 110 ). At this time, the data conversion request unit  11  does not issue the job ID data and the conversion request data TRD does not include the job ID data. The data conversion request unit  11  sends the conversion request data TRD for requesting the converting of application data to print data to the data conversion apparatus  200  (step S 112 ). 
       (Operation by Data Conversion Apparatus  200 ) 
       [0172]    When the data conversion apparatus  200  receives the request of converting application data to print data from the data processing apparatus  100 , the data conversion request receiving unit  21  indicates the job ID issuing unit  211  to issue job ID data for the application data included in the received conversion request data TRD (step S 114 ). The data conversion request receiving unit  21  generates the job ID notification data JRD including the issued job ID data, and sends the generated job ID notification data JRD to the data processing apparatus  100  (step S 116 ). 
         [0173]    Subsequently, the data conversion request receiving unit  21  indicates the data conversion unit  22  to convert the received application data to print data (step S 201 ). Then, the data conversion unit  22  converts the application data to the print data. 
       (Operation by Data Processing Apparatus  100 ) 
       [0174]    In the data processing apparatus  100 , when the job ID notification data JRD is sent from the data conversion apparatus  200 , the data conversion request unit  11  indicates the print request unit  13  to send a request of printing (step S 107 ). At this time, the data conversion request unit  11  outputs the received job ID data and the converting apparatus data to the print request unit  13 . 
         [0175]    Then, the print request unit  13  generates the print request data PRD including the job ID data and the converting apparatus data (step S 108 ). The print request unit  13  sends the print request data PRD for requesting the obtaining of the print data and printing the obtained print data to the image processing apparatus  300  (step S 109 ). 
       (Operation by Image Processing Apparatus  300 ) 
       [0176]    When the image processing apparatus  300  receives the request of obtaining the print data and printing the obtained print data from the data processing apparatus  100 , the print request receiving unit  31  indicates the print data obtaining unit  32  to send a request of sending print data (step S 301 ). Then, the image processing apparatus  300  performs operations of obtaining the print data from the data conversion apparatus  200  and printing the obtained print data. 
         [0177]    As described above, according to the print control system  1  of the embodiment, the data conversion request unit  11  of the data processing apparatus  100  connected to the internal network N sends the request data TRD including the application data to be processed for requesting the converting of the application data to the print data to the data conversion apparatus  200  connected to the external network I. Then, the data conversion request receiving unit  21  of the data conversion apparatus  200  issues the job ID data for the application data to be processed. 
         [0178]    With this, in the data conversion apparatus  200 , the data conversion request receiving unit  21  sends the job ID notification data JRD including the issued job ID data to the data processing apparatus  100 . Subsequently, in the data conversion apparatus  200 , the data conversion unit  22  converts the received application data to the print data. The print data is corresponded with the job ID data. 
         [0179]    In the data processing apparatus  100 , when the data conversion apparatus  200  sends the job ID notification data JRD, the print request unit  13  sends the print request data PRD including the job ID data issued by the data conversion apparatus  200  and the converting apparatus data to the image processing apparatus  300  selected to print connected to the internal network N. With this, in the image processing apparatus  300 , the print data obtaining unit  32  sends a request of sending the print data to the conversion apparatus  200  selected to convert based on the converting apparatus data and the job ID data, and the print control unit  33  prints the obtained print data. 
         [0180]    With this, in the print control system  1  of the embodiment, similar to the first embodiment, it is possible to perform a pseudo-push type printing using the data conversion apparatus  200  connected to the external network I. 
       (Alternative Example) 
       [0181]    The conversion request data TRD sent from the data processing apparatus  100  to the data conversion apparatus  200  may potentially not include the conversion format data, in addition to the job ID data. In such a case, the conversion request data TRD may include only the printer ID data in addition to the application data. In this case, the processes are as follows. 
         [0182]    When the data conversion apparatus  200  receives the conversion request data TRD from the data processing apparatus  100 , the data conversion request receiving unit  21  indicates the data conversion unit  22  to convert the received application data to print data. Then, upon receiving the received application data, the printer ID data, and the issued job ID data from the data conversion request receiving unit  21 , the data conversion unit  22  enters a wait state for the data conversion. 
         [0183]    In the image processing apparatus  300 , upon receiving the print request data PRD from the data processing apparatus  100 , the print request receiving unit  31  sends the conversion format data such as the PDL identifier adaptable for the image processing apparatus  300 , to the data conversion request receiving unit  21  of the data conversion apparatus  200 . 
         [0184]    When the data conversion apparatus  200  receives the conversion format data from the image processing apparatus  300 , the data conversion request receiving unit  21  outputs the received conversion format data to the data conversion unit  22 . Then, the data conversion unit  22  starts converting the application data based on the received conversion format data. 
         [0185]    As described above, in this example, the same merits can be obtained by a different method as the print control function of the embodiment. 
       Third Embodiment 
       [0186]    In the above embodiment, the image processing apparatus  300  is configured to repeat sending the request of sending print data after a predetermined period when the status information is sent to the image processing apparatus  300  from the data conversion apparatus  200  until the print data is sent. At this time, data are periodically sent and received between the image processing apparatus  300  and the data conversion apparatus  200 . Thus, if there are a large number of image processing apparatuses  300  which send the request to the data conversion apparatus  200  exists, for example, a load of a data communication process becomes large to cause a delay in printing. 
         [0187]    Thus, in this embodiment, the data conversion apparatus  200  is configured to predict time necessary to convert the application data to be processed to print data when receiving the request of converting application data to print data and send the predicted time to the data processing apparatus  100 . With this, in this embodiment, an environment in which the load of a data communication process between the image processing apparatus  300  and the data conversion apparatus  200  is reduced can be provided. 
         [0188]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
       (Print Control Function) 
       [0189]      FIG. 15  is a block diagram showing an example of the print control function of the embodiment. 
         [0190]    As shown in  FIG. 15 , in this embodiment, the data conversion unit  22  of the data conversion apparatus  200  further includes a time calculation unit  212  in addition to the job ID issuing unit  211  shown in  FIG. 12  of the second embodiment. Further, in this embodiment, the functions of the data conversion request unit  11  and the print request unit  13  of the data processing apparatus  100 , the data conversion unit  22  of the data conversion apparatus  200 , and the print data obtaining unit  32  of the image processing apparatus  300  are different from those of the second embodiment. 
       (Data Processing Apparatus  100  and Data Conversion Apparatus  200 ) 
       [0191]    In the data processing apparatus  100 , the data conversion request unit  11  sends the conversion request data TRD as shown in  FIG. 16A , for example, to the data conversion apparatus  200  for requesting the converting to the print data. Then, in the conversion apparatus  200 , upon receiving the request of converting application data to print data, the data conversion request receiving unit  21  issues job ID data by the job ID issuing unit  211  and predicts time necessary for converting the application data to be processed to print data by the time calculation unit  212 . Subsequently, the data conversion request receiving unit  21  sends the issued job ID data and the predicted time to the data processing apparatus  100  in response. 
         [0192]      FIG. 16A  is a view showing an example of conversion request data TRD of the embodiment. As shown in  FIG. 16A , the conversion request data TRD includes data corresponding to an item such as “size”, which indicates size of the application data to be processed, in addition to the conversion format data and the printer ID data. 
         [0193]    Data corresponding to the item “size” (hereinafter simply referred to “size data”) indicates the size of the application data to be processed. The size data may be a data size value or a file size value (hereinafter simply referred to as a “data size value”) capable of being obtained from a property or the like of the application data. 
         [0194]    Referring back to  FIG. 15 , in the data processing apparatus  100 , when a user selects application data (job) to be processed and the image processing apparatus  300  to print via the operation panel, the data conversion request unit  11  accepts the selections. At this time, the data conversion request unit  11  obtains the size data from the property or the like of the selected application data. Then, the data conversion request unit  11  generates the conversion request data TRD including the selected application data, the conversion format data, the printer ID data and the data size value, and sends the conversion request data TRD to the data conversion apparatus  200 . 
         [0195]    In the data conversion apparatus  200 , when the data conversion request receiving unit  21  receives the request of converting application data to print data, the time calculation unit  212  calculates time necessary for converting the received application data to print data of the set conversion format based on the received conversion format data and the size data. 
         [0196]      FIG. 16B  is a view showing an example of job ID-predicted time notification data JTRD. 
         [0197]    Data corresponding to the item “predicted time” (hereinafter referred to as “predicted time data”) indicates a value of predicted time necessary for converting the application data to be processed to print data. The predicted time data is predicted (calculated) by the time calculation unit  212  of the data conversion request receiving unit  21 . 
         [0198]    As shown in  FIG. 16B , the job ID-predicted time notification data JTRD includes the job ID data and the predicted time data. The job ID data is issued by the job ID issuing unit  211  of the data conversion request receiving unit  21 . 
         [0199]      FIG. 17  is a view showing an example of calculation data  212 D for calculating the predicted time. 
         [0200]    When calculating the predicted time, the time calculation unit  212  may refer to the calculation data  212 D shown in  FIG. 17 , for example, and calculates the predicted time in accordance with a method of calculation previously set for each of the conversion format data. 
         [0201]    As shown in  FIG. 17 , the calculation data  212 D includes one or more data sets in each of which the conversion format data and the method of calculation corresponding with each other. The data set is prepared for each of the conversion format data. 
         [0202]    The item “conversion format” indicates the conversion format data, and may be PDL identifier or the like. The item “method of calculation” indicates the method of calculation of the predicted time. For the data corresponding to the item “method of calculation” may be a formula for calculating the predicted time by inputting size data as a parameter value. 
         [0203]    The conversion format data are previously set based on the conversion formats adaptable for the data conversion apparatus  200 . For the method of calculation, formulas may be obtained by actually converting application data of various data size to print data of various conversion formats by the data conversion apparatus  200 . For the formulas shown in  FIG. 17 , “x” expresses the data size of original data and “y” expresses the predicted time necessary for converting the application data to print data. 
         [0204]    Referring back to  FIG. 15 , in the data conversion apparatus  200 , the time calculation unit  212  refers to the calculation data  212 D and specifies the “method of calculation” corresponding to the conversion format data which is the same as the received conversion format data. The time calculation unit  212  inputs the size data as the parameter value of the specified “method of calculation” and calculates the predicted time necessary for converting the received application data to the print data of the specified conversion format. Further, the time calculation unit  212  adds the calculated predicted time to a receiving time of the application data (receiving time of the request of converting application data to print data) and sets the added value as the predicted time data. 
         [0205]    Then, the data conversion request receiving unit  21  sends the job ID-predicted time notification data JTRD including the job ID data issued by the job ID issuing unit  211  and the predicted time data calculated by the time calculation unit  212  to the data processing apparatus  100  in response. 
         [0206]    Then, in the data processing apparatus  100 , the data conversion request unit  11  outputs the job ID data and the predicted time data of the job ID-predicted time notification data JTRD received from the data conversion request receiving unit  21  of the data conversion apparatus  200  to the print request unit  13  with the converting apparatus data to indicate to send a request of obtaining the print data and printing the obtained print data. 
         [0207]    As described above, in the print control system  1  of the embodiment, upon receiving the request of converting application data to print data from the data processing apparatus  100 , the data conversion apparatus  200  is configured to automatically issue job ID data for the application data included in the request, calculate predicted time data, and reply to the data processing apparatus  100  which has sent the request. 
         [0208]    Further, in this embodiment, the time calculation unit  212  is configured to include the calculation data  212 D (the method of calculation is included in the software for actualizing the time calculation function). However, alternatively, the calculation data  212 D may be stored in a predetermined storage area as external data, and the time calculation unit  212  may access and refer to the calculation data  212 D stored in the predetermined storage area. 
       (Image Processing Apparatus  300 ) 
       [0209]    The print request unit  13  of the data processing apparatus  100  sends the print request data PRD as shown in  FIG. 18  to the image processing apparatus  300 , for example. 
         [0210]      FIG. 18  is a view showing an example of the print request data PRD of the embodiment. 
         [0211]    As shown in  FIG. 18 , the print request data PRD includes the predicted time data in addition to the job ID data and the converting apparatus data. 
         [0212]    Referring back to  FIG. 15 , the print request receiving unit  31  outputs the job ID data, the converting apparatus data, and the predicted time data included in the received print request data PRD to the print data obtaining unit  32  and indicates the print data obtaining unit  32  to send a request of sending print data. 
         [0213]    Then, the print data obtaining unit  32  sends the request of sending print data to the data conversion apparatus  200  based on the predicted time data. Specifically, the print data obtaining unit  32  accesses the data conversion apparatus  200  after the time defined by the predicted time data has passed and sends the request command of sending print data including the job ID data. 
         [0214]    As described above, in the print control system  1  of the embodiment, the data processing apparatus  100  sends the print request data PRD including the predicted time data for the application data to be processed to the image processing apparatus  300 . Then, the image processing apparatus  300  controls the timing of obtaining the print data from the data conversion apparatus  200  based on the received predicted time data. Thus, according to the print control system  1  of the embodiment, as the image processing apparatus  300  obtains the print data at an appropriate timing after the application data to be processed is converted from the data conversion apparatus  200 , the load of a data communication process between the apparatuses can be reduced. 
         [0215]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
         [0216]    The operation of the print control function of the embodiment is explained in detail with respect to a sequence diagram. 
         [0217]      FIG. 19  is a sequence diagram showing an example of an operation of print control of the embodiment. 
       (Operation by Data Processing Apparatus  100 ) 
       [0218]    Upon an instruction from the user, the data conversion request unit  11  of the data processing apparatus  100  displays an operation panel and accepts selections of application data to be processed and the image processing apparatus  300  to print the selected application data. Then, the data conversion request unit  11  indicates the printer information obtaining unit  12  to obtain the printer information of the selected image processing apparatus  300  (step S 101 ). Then, the data conversion request unit  11  refers to the printer information obtained by the printer information obtaining unit  12  (step S 102 ). 
         [0219]    Subsequently, the data conversion request unit  11  generates the conversion request data TRD including the selected application data, the size data of the application data obtained from the property or the like of the application data, and the conversion format data and the printer ID data obtained from the printer information (step S 120 ). The data conversion request unit  11  sends the generated conversion request data TRD to the data conversion apparatus  200  for requesting the converting of the application data to print data (step S 122 ). 
       (Operation by Data Conversion Apparatus  200 ) 
       [0220]    When the data conversion apparatus  200  receives the request of converting application data to print data from the data processing apparatus  100 , the data conversion request receiving unit  21  indicates the job ID issuing unit  211  to issue job ID data for the application data included in the received conversion request data TRD. Further, the data conversion request receiving unit  21  indicates the time calculation unit  212  to calculate the predicted time necessary for converting the received application data to the print data of the set conversion format based on the conversion format data and the size data of the received conversion request data TRD (step S 124 ). At this time, the time calculation unit  212  refers to the calculation data  212 D, inputs the size data as the parameter value of the formula corresponding to the set conversion format to obtain the predicted time. Further, the time calculation unit  212  adds the calculated predicted time to a receiving time of the request of converting application data to print data to generate the predicted time data. 
         [0221]    The data conversion request receiving unit  21  generates the job ID-predicted time notification data JTRD including the issued job ID data and the calculated predicted time data, and sends the generated job ID-predicted time notification data JTRD to the data processing apparatus  100  as a reply (step S 126 ). 
       (Operation by Data Processing Apparatus  100 ) 
       [0222]    In the data processing apparatus  100 , when the job ID-predicted time notification data JTRD is sent from the data conversion apparatus  200 , the data conversion request unit  11  indicates the print request unit  13  to send a request of printing (step S 128 ). At this time, the data conversion request unit  11  outputs the job ID data and the predicted time data of the received job ID-predicted time notification data JTRD and the converting apparatus data to the print request unit  13 . 
         [0223]    Then, the print request unit  13  generates the print request data PRD including the job ID data, the converting apparatus data, and the predicted time data (step S 130 ). The print request unit  13  sends the generated print request data PRD for requesting the obtaining of the print data and printing the obtained print data to the image processing apparatus  300  (step S 132 ). 
       (Operation by Data Conversion Apparatus  200 ) 
       [0224]    Referring back to the explanation of the data conversion apparatus  200 , when the data conversion apparatus  200  receives the request of converting application data to print data from the data processing apparatus  100 , the data conversion request receiving unit  21  indicates the data conversion unit  22  to convert the received application data to print data (step S 201 ). At this time, the data conversion request receiving unit  21  accesses the management information storing unit  90 , records the issued job ID data and the printer ID data included in the received conversion request data TRD, and generates a data set of the management information  90 D for the received request of converting application data to print data. 
         [0225]    Then, the data conversion request receiving unit  21  outputs the issued job ID data, the application data included in the conversion request data TRD, the conversion format data, and the printer ID data to the data conversion unit  22 . 
         [0226]    Then, the data conversion unit  22  starts converting the application data to the print data (step S 202 ). At this time, the data conversion unit  22  converts the application data to print data of the conversion format specified by the conversion format data. Meanwhile, the data conversion unit  22  records the status of the conversion “start conversion” or “converting” for the item “status” in the data set of the management information  90 D generated by the data conversion request receiving unit  21 . The data conversion unit  22  may periodically update the status of the conversion in accordance with the operation. 
         [0227]    The data conversion unit  22  indicates the print data sending unit  23  to wait for a request of sending print data from the image processing apparatus  300  (step S 203 ). At this time, the data conversion unit  22  outputs the printer ID data to the print data sending unit  23 . 
         [0228]    Then, the print data sending unit  23  starts waiting for the request of sending print data from the image processing apparatus  300  identified by the printer ID data (step S 204 ). The print data sending unit  23  enters a wait state for the request of sending print data image from the processing apparatus  300 . 
         [0229]    When the data conversion unit  22  of the data conversion apparatus  200  completes the conversion of the application data to the print data, the data conversion unit  22  stores the print data in the predetermined storage area (step S 205 ). At this time, the data conversion unit  22  records the access path to the stored converted print data for the item “access path” of the management information  90 D. Further, the data conversion unit  22  updates the status of the conversion for the item “status” of the management information  90 D to “converted (completed)”. 
         [0230]    When the print data sending unit  23  receives the request of sending print data from the identified image processing apparatus  300  after the predicted time has passed, the print data sending unit  23  accesses the management information storing unit  90 , and refers to the status information of the management information  90 D specified by the received job ID data. As the status information of the management information  90 D is “converted (completed)” at this time, the print data sending unit  23  obtains the converted print data based on the access path data, and sends the converted print data to the corresponding image processing apparatus  300  in response. 
       (Operation by Image Processing Apparatus  300 ) 
       [0231]    When the image processing apparatus  300  receives the request of obtaining the print data and printing the obtained print data from the data processing apparatus  100 , the print request receiving unit  31  indicates the print data obtaining unit  32  to send a request of sending print data (step S 310 ). At this time, the print request receiving unit  31  outputs the job ID data, the converting apparatus data and the predicted time data included in the received print request data PRD to the print data obtaining unit  32 . 
         [0232]    Then, the print data obtaining unit  32  starts sending the request of sending print data to the data conversion apparatus  200  based on the predicted time data (step S 302 ). Specifically, the print data obtaining unit  32  starts sending the request of sending print data after the predicted time of the predicted time data has passed. At this time, the print data obtaining unit  32  accesses the data conversion apparatus  200  identified by the converting apparatus data, and sends the request of sending print data by sending a request command of sending print data of the application data to be processed including the job ID data (step S 4021 ). At this time, when the application data identified by the job ID data is converted to the print data by the data conversion apparatus  200 , the converted print data is sent to the print data obtaining unit  32  (step S 4022 ). 
         [0233]    With this operation, the print data obtaining unit  32  ends sending the request of sending print data, and indicates the print control unit  33  to print the obtained print data (step S 303 ). At this time, the print data obtaining unit  32  outputs the received print data to the print control unit  33 . 
         [0234]    Then, the print control unit  33  outputs the print data to the plotter (not shown in the drawings) included in the image processing apparatus  300 , and performs printing in accordance with a predetermined printing condition (step S 304 ). 
         [0235]    As described above, according to the print control system  1  of the embodiment, in the data processing apparatus  100  connected to the internal network N, the data conversion request unit  11  sends the request data TRD including the application data to be processed to the data conversion apparatus  200  connected to the external network I for requesting a conversion of the application data to print data. 
         [0236]    Then, in the data conversion apparatus  200 , the data conversion request receiving unit  21  issues job ID data for the application data to be processed. Further, in the data conversion apparatus  200 , the data conversion request receiving unit  21  calculates the predicted time data indicating the predicted time necessary for converting the application data to be processed to print data. 
         [0237]    Then, in the data conversion apparatus  200 , the data conversion request receiving unit  21  sends the job ID-predicted time notification data JTRD including the issued job ID data and the calculated predicted time data to the data processing apparatus  100  in response. Thereafter, in the data conversion apparatus  200 , the data conversion unit  22  converts the received application data to print data. 
         [0238]    Further, when the data processing apparatus  100  receives a response from the data conversion apparatus  200 , the print request unit  13  sends the request data PRD including the converting apparatus data, and the issued job ID data and the calculated predicted time data by the data conversion apparatus  200  to the image processing apparatus  300  selected to print connected to the internal network N for requesting the printing. 
         [0239]    Then, in the image processing apparatus  300 , the print data obtaining unit  32  requests sending the print data based on the job ID data in accordance with a controlled timing after the predicted time has passed based on the predicted time data to the data conversion apparatus  200  selected to convert. Then, the print control unit  33  prints the obtained print data. 
         [0240]    With this, the print control system  1  of the embodiment can provide an environment in which the load of a data communication process between the image processing apparatus  300  and the data conversion apparatus  200  is reduced to perform a pseudo-push type printing using the data conversion apparatus  200  connected to the external network I. 
       Fourth Embodiment 
       [0241]    In the print control system  1 , the data conversion apparatus  200  may convert application data to print data using a conversion format for which conversion time is short when considering a speed of a printing operation. 
         [0242]    Thus, in this embodiment, the data conversion apparatus  200  is configured to predict a time necessary for converting application data to print data of each of conversion formats adaptable for the image processing apparatus  300  selected to print when receiving a request of converting application data to print data. Then, the data conversion apparatus  200  is configured to determine the conversion format for which the predicted time is the shortest to be the conversion format of print data converted from the application data to be processed. With this, in this embodiment, a printing environment which is convenient and with a high-speed can be provided. 
         [0243]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
       (Print Control Function) 
       [0244]      FIG. 20  is a block diagram showing an example of the print control function of the embodiment. 
         [0245]    As shown in  FIG. 20 , in this embodiment, the data conversion unit  22  of the data conversion apparatus  200  further includes a conversion format determining unit  213  in addition to the job ID issuing unit  211  and the time calculation unit  212  shown in  FIG. 15  of the third embodiment. Further, in this embodiment, the functions of the data conversion request unit  11  and the print request unit  13  of the data processing apparatus  100 , and the data conversion unit  22  of the data conversion apparatus  200  are different from those of the second embodiment. 
       (Data Processing Apparatus  100  and Data Conversion Apparatus  200 ) 
       [0246]    In the data processing apparatus  100 , the data conversion request unit  11  sends the conversion request data TRD to the data conversion apparatus  200  for requesting a conversion to the print data. At this time, the conversion request data TRD sent from the data conversion request unit  11  to the data conversion apparatus  200  includes the printer ID data, the size data or the like, but does not include the conversion format data. 
         [0247]    In the data conversion apparatus  200 , when the data conversion request receiving unit  21  receives the request of converting application data to print data, the data conversion request receiving unit  21  sends the job ID issued for the received application data to be processed and the predicted time necessary for converting the application data to be processed to the data processing apparatus  100  in response. 
         [0248]    At this time, the time calculation unit  212  of the data conversion request receiving unit  21  refers to the calculation data  212 D, and calculates predicted times necessary for converting the received application data to print data for all of the conversion formats in accordance with the predetermined methods of calculation based on the received size data. In other words, the time calculation unit  212  calculates the predicted times for all of the conversion formats which are capable of being printed by the image processing apparatus  300  to print. Specifically, for example, when the image processing apparatus  300  is capable of printing print data whose conversion format are “PCL”, “PS”, and “RPCS”, the data conversion request receiving unit  21  calculates predicted times necessary for converting the received application data to print data of these three conversion formats in accordance with the predetermined methods for each of the conversion formats. 
         [0249]    Then, the conversion format determining unit  213  of the data conversion request receiving unit  21  determines the conversion format to be used based on the predicted time data calculated by the time calculation unit  212 . At this time, the conversion format determining unit  213  compares the calculated predicted time data and selects the conversion format by which the predicted time becomes the shortest as the conversion format to be used. In other words, the conversion format determining unit  213  determines the conversion format by which the conversion of the application data to the print data is completed the fastest as the conversion format to be used. 
         [0250]    Then, in the data conversion apparatus  200 , the data conversion request receiving unit  21  sends the job ID-predicted time notification data JTRD including the job ID data issued by the job ID issuing unit  211 , the predicted time data calculated by the time calculation unit  212  and selected by the conversion format determining unit  213  to the data processing apparatus  100  in response. 
         [0251]    Further, the data conversion request receiving unit  21  outputs the conversion format data determined by the conversion format determining unit  213  to the data conversion unit  22  with the received application data and the printer ID data and instructs to convert the application data to print data. 
         [0252]    As described above, according to the print control system  1  of the embodiment, the data conversion apparatus  200  determines the conversion format by which the conversion time necessary for converting the application data to the print data becomes the shortest as the conversion format to be used based on the predicted time data for the conversion formats applicable for the image processing apparatus  300  to print. 
         [0253]    It is to be noted that, in the explanation of the drawings, the same components are given the same reference numerals, and explanations are not repeated. 
         [0254]    The operation of the print control function of the embodiment is explained in detail with respect to a sequence diagram. 
         [0255]      FIG. 21  is a sequence diagram showing an example of an operation of print control of the embodiment. For the operation shown in  FIG. 21 , processes from steps S 101  to S 120 , steps S 128  to S 132 , after step S 203 , and after step S 310  are the same as those shown in  FIG. 19 , and thus the explanation is not repeated. Only steps S 133  to S 135 , and steps S 210  and S 212  which are different from those shown in  FIG. 19  are explained. 
       (Operation by Data Processing Apparatus  100 ) 
       [0256]    As shown in  FIG. 21 , the data conversion request unit  11  of the data processing apparatus  100  sends a request of converting application data to print data with the conversion request data TRD to the data conversion apparatus  200  (step S 133 ). At this time, as described above, the conversion request data TRD does not include the conversion format data. 
       (Operation by Data Conversion Apparatus  200 ) 
       [0257]    When the data conversion apparatus  200  receives the request of converting application data to print data from the data processing apparatus  100 , the job ID issuing unit  211  of the data conversion request receiving unit  21  issues job ID data for the received application data included in the received conversion request data TRD (step S 134 ). 
         [0258]    Further, in step S 134 , the time calculation unit  212  of the data conversion request receiving unit  21  calculates predicted times necessary for converting the received application data to print data for all of the conversion formats capable of being printed by the image processing apparatus  300  based on the size data included in the received conversion request data TRD (STEP  1  in step S 134 ). At this time, the time calculation unit  212  refers to the calculation data  212 D, inputs the data size as a parameter value for each of the formulas corresponding to the conversion formats to obtain the predicted time for each of the conversion formats, and adds the predicted times to the receiving time of the request of converting application data to print data. 
         [0259]    Then, the conversion format determining unit  213  of the data conversion request receiving unit  21  determines the conversion format to be used based on the calculated predicted time data to be the conversion format data (STEP  2  in step S 134 ). At this time, as described above, the conversion format determining unit  213  compares the predicted time data for each of the conversion formats, and selects the conversion format by which the predicted time is the shortest to be the conversion format to be used to be the conversion format data. 
         [0260]    Then, the data conversion request receiving unit  21  generates the job ID-predicted time notification data JTRD including the issued job ID data and the predicted time data of the selected conversion format, and sends the generated job ID-predicted time notification data JTRD to the data processing apparatus  100  as a response (step S 135 ). 
       (Operation by Data Conversion Apparatus  200 ) 
       [0261]    Further, when the conversion format determining unit  213  determines the conversion format to be used, the data conversion request receiving unit  21  indicates the data conversion unit  22  to convert the received application data to the print data (step S 201 ). At this time, the data conversion request receiving unit  21  accesses the management information storing unit  90 , records the issued job ID data and the printer ID data included in the received conversion request data TRD, and generates a data set of the management information  90 D for the received request of converting application data to print data. Further, the data conversion request receiving unit  21  outputs the issued job ID data, the determined conversion format data, and the application data, and the printer ID data included in the conversion request data TRD to the data conversion unit  22 . 
         [0262]    Then, the data conversion unit  22  starts converting the application data to the print data (step S 202 ). At this time, the data conversion unit  22  converts the application data to the print data of the data format based on the determined conversion format data, by which the data conversion finished first. Meanwhile, the data conversion unit  22  records the status of the conversion “start conversion” or “converting” for the item “status” in the data set of the management information  90 D generated by the data conversion request receiving unit  21 . The data conversion unit  22  may periodically update the status of the conversion in accordance with the operation. 
         [0263]    As described above, according to the print control system  1  of the embodiment, the data processing apparatus  100  connected to the internal network N sends the request data TRD including the application data to be processed by the data conversion request unit  11 , to the data conversion apparatus  200  connected to the external network I for requesting the converting of the application data to print data. In response, in the data conversion apparatus  200 , the data conversion request receiving unit  21  issues job ID data for the application data to be processed. Further, in the data conversion apparatus  200 , the data conversion request receiving unit  21  calculates the predicted time necessary for converting the application data to be processed as the predicted time data. Further, in the data conversion apparatus  200 , the data conversion request receiving unit  21  determines the conversion format by which the predicted time becomes the shortest as the conversion format to be used. 
         [0264]    With this, in the data conversion apparatus  200 , the data conversion request receiving unit  21  sends the job ID-predicted time notification data JTRD including the issued job ID data and the predicted time data of the determined conversion format to the data processing apparatus  100  in response. Thereafter, in the data conversion apparatus  200 , the data conversion unit  22  converts the application data based on the conversion format data of the determined conversion format to the print data. 
         [0265]    Further, when the data processing apparatus  100  receives the job ID data and the predicted time data of the application data to be processed from the data conversion apparatus  200 , the print request unit  13  sends a request of printing to the image processing apparatus  300  selected to print connected to the internal network N by sending the print request data PRD including the issued job ID data, the predicted time data, and converting apparatus data. 
         [0266]    In response to this, in the image processing apparatus  300 , the print data obtaining unit  32  sends a request of sending the print data to the data conversion apparatus  200  selected to convert based on the job ID data in accordance with a timing controlled by the predicted time data. Then, when the print data is obtained, the print control unit  33  pints the obtained print data. 
         [0267]    With this, according to the print control system  1  of the embodiment, a printing environment which is convenient with a high-speed can be provided. Further, the print control system  1  is capable of providing a pseudo-push type printing using the data conversion apparatus  200  connected to the external network I. 
         [0268]    The “print control function” of the above embodiments can be actualized by executing the programs in which the above processes explained with reference to drawings are coded by programming languages in accordance with the respective operating environments (platforms) by the arithmetic units (CPU) of the apparatuses (the data processing apparatuses  100 , the data conversion apparatuses  200 , the image processing apparatuses  300  and the like) of the print control system  1 . 
         [0269]    The above programs may be stored in a computer readable recording medium  103   a . With this, for example, for the data processing apparatus  100 , the above programs may be installed in the data processing apparatus  100  via the external I/F  103 . Further, as the data processing apparatus  100  includes the communication I/F  107 , the above programs may be downloaded using an electrical communication line and installed. 
         [0270]    According to the embodiments, a print control system, a method of controlling printing, a data processing apparatus, and a recording medium in which a pseudo-push type printing using a data conversion apparatus connected to an external network data conversion apparatus can be performed is provided. 
         [0271]    The individual constituents of the print control system  1  may be embodied by arbitrary combinations of hardware and software, typified by a CPU of an arbitrary computer, memory, a program loaded in the memory so as to embody the constituents illustrated in the drawings, storage units for storing the program such as a hard disk, and an interface for network connection. It may be understood by those skilled in the art that methods and devices for the embodiment allow various modifications. 
         [0272]    Although a preferred embodiment of the print control system  1  has been specifically illustrated and described, it is to be understood that minor modifications may be made therein without departing from the sprit and scope of the invention as defined by the claims. 
         [0273]    The present invention is not limited to the specifically disclosed embodiments, and variations and modifications may be made without departing from the scope of the present invention.