Abstract:
Disclosed is a print controlling device including a control unit to control printing according to an instruction which relates to the printing, wherein the control unit analyzes a page description language which relates to the printing, determines whether the printing is practically monochrome printing or color printing, and changes a first command of the page description language to a second command for monochrome printing when it is determined that the printing is monochrome printing.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to a print controlling device, an image forming device provided with the print controlling device, a print controlling method, and a computer readable recording medium storing a control program.  
         [0003]     2. Description of the Related Art  
         [0004]     When a monochrome document prepared by an application for document preparation is printed by a color printer, there is a case where the monochrome document is processed as a color document. This is caused, since a particular application generates a data to conduct processing of the monochrome document as a color document at a printer driver, the printer driver outputs data using a command which assigns color. At an interpreter, since the command assigns color, processing is conducted as color, and color printing is executed. Therefore, even for a monochrome document, unnecessary color processing and the like are conducted, resulting in decrease in processing speed. In addition, in case of a printer which charges for color printing, inconvenience arose in that money was charged even when it was a monochrome document.  
         [0005]     Concerning above problems, a technique for processing monochrome document as a monochrome is in demand. As for such technique, for example, in Japanese Laid-open Patent Specification No. 2004-243569, a technique to draw as monochrome for data sent as monochrome, and to draw as color for data sent as color, is disclosed. According to the technique, information, indicating whether each pixel is a color pixel or a monochrome pixel, is attached to information plane (Tag bit) when a draw command (PDL (Page Description Language) data) is converted into a bit map data.  
         [0006]     However, concerning the above conventional image forming device, it was determined whether a printing is a color printing or a monochrome printing, after conversion to bit map (after rasterization). Therefore, burden of processing was large, and decrease in processing speed and determination accuracy were likely to occur.  
       SUMMARY  
       [0007]     The present invention has been made to solve the above problem. An object of the present invention is to increase processing speed and to improve determination accuracy, by determining whether a printing is a color printing or a monochrome printing, based on a page description language.  
         [0008]     A printing controlling device according to an embodiment reflecting one aspect of the invention comprises: a control unit to control printing according to an instruction which relates to the printing; wherein the control unit: analyzes a page description language which relates to the printing, and determines whether the printing is practically monochrome printing or color printing; and changes a first command of the page description language to a second command for monochrome printing when it is determined that the printing is monochrome printing.  
         [0009]     Preferably, the control unit does not conduct a following determination processing which relates to the printing when it is determined that the printing is color printing.  
         [0010]     Additionally, the control unit may determine whether the printing is practically monochrome printing or color printing for each page.  
         [0011]     An image forming device according to an embodiment reflecting another aspect of the invention comprises: a receiving unit to receive an instruction which relates to printing; a control unit to control the printing according to the instruction which relates to the printing received by the receiving unit; and a printing unit to execute the printing according to a control from the control unit; wherein the control unit: analyzes a page description language which relates to the printing, and determines whether the printing is practically monochrome printing or color printing; and changes a first command of the page description language to a second command for monochrome printing when it is determined that the printing is monochrome printing.  
         [0012]     Preferably, the control unit does not conduct a following determination processing which relates to the printing when it is determined that the printing is color printing.  
         [0013]     Additionally, the control unit may determine whether the printing is practically monochrome printing or color printing for each page.  
         [0014]     A print controlling method according to an embodiment reflecting one aspect of the invention comprises: an analyzing and determining step to analyze a page description language which relates to a printing, and determine whether the printing is practically monochrome printing or color printing; and a changing step to change a first command of the page description language to a second command for monochrome printing when it is determined that the printing is monochrome printing.  
         [0015]     Preferably, a following determination processing which relates to the printing is not conducted when it is determined that the printing is color printing.  
         [0016]     Additionally, determination whether the printing is practically monochrome printing or color printing may be conducted for each page.  
         [0017]     A computer readable recording medium according to an embodiment reflecting another aspect of the invention that stores a control program which is executed by a control unit of print controlling device that controls printing according to an instruction which relates to the printing, the control program causing the control unit execute: a analyzing and determining step to analyze a page description language which relates to the printing, and determine whether the printing is practically monochrome printing or color printing; and a changing step to change a first command of the page description language to a second command for monochrome printing when it is determined that the printing is monochrome printing.  
         [0018]     Preferably, the control program does not cause the control unit execute a following determination processing which relates to the printing when it is determined that the printing is color printing.  
         [0019]     Additionally, the control program may cause the control unit execute determination on whether the printing is practically monochrome printing or color printing for each page. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0020]     The present invention will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only, and thus are not intended as a definition of the limits of the scope of the invention, and wherein:  
         [0021]      FIG. 1  is a view showing a structure of an image forming system according to the embodiment of the present invention;  
         [0022]      FIG. 2  is a block diagram showing a structure of main portion of a PC according to the present embodiment;  
         [0023]      FIG. 3  is a block diagram showing a structure of main portion of an image forming device according to the present embodiment;  
         [0024]      FIG. 4  is a flowchart showing a print processing executed by the image forming device according to the present embodiment;  
         [0025]      FIG. 5  is a flowchart showing a color/monochrome processing;  
         [0026]      FIG. 6  is a flowchart showing a color/monochrome determination processing;  
         [0027]      FIG. 7  is a flowchart showing processing of color space set command;  
         [0028]      FIG. 8  is a flowchart showing processing of pen information/brush information set command;  
         [0029]      FIG. 9  is a flowchart showing processing of image pattern information/image information set command; and  
         [0030]      FIG. 10  is a view showing an example of the color space set command. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0031]     An embodiment of the present invention will be described hereinafter with reference to figures.  
         [0032]     First of all, a system structure according to the embodiment will be explained.  
         [0033]      FIG. 1  shows a structure of an image forming system  100  according to the embodiment of the present invention. As shown in  FIG. 1 , the image forming system  100  comprises a PC (Personal Computer)  1  and an image forming device  2 , such as a printer, copy machine, and the like. The PC  1  and the image forming device  2  are connected through a communication network N.  
         [0034]     The communication network N comprises LAN (Local Area Network) which connects apparatuses through standards such as Ethernet (registered trademark), TokenRing, FDDI (Fiber Distributed Data Interface), and the like; WAN (Wide Area Network) which connects the LAN through an exclusive line; and the like.  
         [0035]     Here, the number of PC  1  and the number of image forming device  2  connected to the communication network N are not limited. In addition, connecting means for the PC  1  and the image forming device  2  is not limited to network connection, and may be connected through a local connection.  
         [0036]      FIG. 2  shows a structure of main portion of the PC  1 . As shown in  FIG. 2 , the PC  1  comprises CPU (Central Processing Unit)  10 , ROM (Read Only Memory)  11 , RAM (Random Access Memory)  12 , storage device  13 , operation unit  14 , display unit  15 , and network I/F  16 .  
         [0037]     The CPU  10  controls performance of each unit of the PC  1  according to a control program stored in the ROM  11 . For example, when printing of a file is instructed from the operation unit  14 , the CPU  10 , by using a printer driver which is a software to control printing, executes processing which converts the file into page description languages (PDL) such as PS (PostScript), PCL (Printer Control Language), and the like, and sends them to the image forming device  2  through the network I/F  16 .  
         [0038]     The ROM  11  stores control program to actualize various kinds of performances of the PC  1  executed by the CPU  10 , and data used when the control program is executed.  
         [0039]     The RAM  12  spreads various kinds of control programs executed by the CPU  10  in a program storage area, and temporarily stores data, such as processing result obtained by executing these control programs, in a work area.  
         [0040]     The storage device  13  comprises a recording medium that conducts record reproduction magnetically or optically, a recording medium of a semiconductor memory, and the like, and conducts writing and reading of instructed data. This recording medium is either provided fixedly, or attached in a detachable manner to the storage device  13 .  
         [0041]     The operation unit  14  includes numeric keypad, cursor key, and various kinds of functional keys, and outputs an operation signal by key depression to the CPU  10 .  
         [0042]     The display unit  15  comprises a display such as LCD (Liquid Crystal Display) and the like, and performs required display processing corresponding to a display control signal inputted from the CPU  10 .  
         [0043]     The network I/F  16  is an interface to connect the PC  1  with external device through communication network N. As for the external device, the image forming device  2  and the. like can be mentioned.  
         [0044]      FIG. 3  shows a structure of main portion of the image forming device  2 . As shown in  FIG. 3 , the image forming device  2  comprises CPU  20 , ROM  21 , RAM  22 , HDD (Hard Disc Drive)  23 , USB (Universal Serial Bus) I/F  24 , network I/F  25 , display unit  26 , color/monochrome processing unit  27 , color/monochrome status transition unit  28 , language analysis unit  29 , rasterization processing unit  30 , and printing unit  31 , and are connected through bus  32 .  
         [0045]     The CPU  20  controls performance of each part of the image forming device  2 , according to a control program stored in ROM  21 . Print processing executed under control by the CPU  20  will be described later in detail with reference to  FIG. 4  through  FIG. 10 .  
         [0046]     The ROM  21  stores control program to actualize various kinds of performances with regard to performance of the image forming device  2  executed by the control unit  20 , and data used in case of executing the control program.  
         [0047]     The RAM  22  spreads various kinds of control programs executed by the CPU  20  in the program storage area, and temporarily stores data, such as inputted print data, processing result obtained by executing the various kinds of control programs, and the like in a work area. The HDD  23  stores data such as confidential printing job data and the like.  
         [0048]     The USB I/F  24  is an interface to connect USB memory.  
         [0049]     The network I/F  25  is an interface to connect the image forming device  2  with an external device through communication network N. As for the external device, PC  1  can be mentioned as an example.  
         [0050]     The display unit  26  comprises a display such as LCD (Liquid Crystal Display) and the like. According to display control signal inputted from the CPU  20 , the display unit  26  displays icons and key buttons, or displays various kinds of settings required for printing. The display unit  26  is provided with a touch-sensitive panel which covers the display, and detects coordinates by coordinate reading principles such as electromagnetic guidance, magnetostriction, pressure sensing, or the like, and outputs detected coordinates as a position signal to the CPU  20 .  
         [0051]     The color/monochrome processing unit  27 , by analyzing page description language included in a print data inputted from PC  1  through the network I/F  25 , determines whether the printing is practically a monochrome printing or a color printing, for each page. In case the color/monochrome processing unit  27  determines that it is a monochrome printing, a command of page description language is converted into a command for monochrome printing and outputted to the language analysis unit  29 .  
         [0052]     The color/monochrome status transition unit  28  manages a state transition of a current page that is analyzed by the color/monochrome processing unit  27 . In the present embodiment, four state transitions as mentioned below are defined. Page description language will be referred to as PDL hereinafter.  
         [0000]     [RGB]: A state in case a command of PDL assigns RGB, and it is not possible to determine whether content is Gray or not;  
         [0000]     [Gray]: A state in case a command of PDL assigns Gray;  
         [0000]     [RGB→Gray]: A state in case a command of PDL assigns RGB, content is determined as Gray, and the command is replaced so as to assign Gray;  
         [0000]     [Only RGB]: A state in case a command of PDL assigns RGB, and content is determined as RGB.  
         [0053]     Here, while a command within a page is analyzed, in case a state transition becomes [Only RGB] once, it is regarded that the page has already been assigned a command for color, and color printing is conducted. Therefore, color/monochrome determination processing (step S 11  in  FIG. 5 ) is not conducted thereinafter within that page.  
         [0054]     The language analysis unit  29  analyzes print data inputted from PC  1  through network I/F  25  and color/monochrome processing unit  27 , and generates intermediate data. Intermediate data is a data before spreading it into a bit map data, and can be stored in small portion compared to the bit map data.  
         [0055]     The rasterization processing unit  30  converts the intermediate data generated by language analysis unit  29  into a printable bit map data.  
         [0056]     The printing unit  31  prints the bit map data generated by the rasterization processing unit  30  by a predetermined method of printing (laser beam method, for example).  
         [0057]     Here, according to the present embodiment, each of the color/monochrome processing unit  27 , the color/monochrome state transition unit  28 , the language analysis unit  29 , and the rasterization unit  30 , are functional module of aforementioned control program, and is actualized by the CPU  20 .  
         [0058]     Next, the performance according to the present embodiment is described.  
         [0059]     First of all, with reference to flowchart of  FIG. 4 , print processing executed under control by the CPU  20  is described.  
         [0060]     When a print data is inputted from PC  1  to the image forming device  2 , print data (PDL) is received at the color/monochrome processing unit  27  (step S 1 ), and it is determined whether the page is the first page or not (step S 2 ).  
         [0061]     In step S 2 , when it is determined that the page is not the first page (step S 2 ; No), a color/monochrome processing ( FIG. 5 ) described later is conducted (step S 4 ). In step S 2 , when it is determined that the page is the first page (step S 2 ; Yes); after the state transition is initialized to [RGB] (step S 3 ), the color/monochrome processing ( FIG. 5 ) described later is conducted (step S 4 ).  
         [0062]     After the color/monochrome processing is completed, analysis of print data is conducted at the language analysis unit  29 , and an intermediate data is generated (step S 5 ). Subsequently, it is determined whether the entire data is received from PC  1  or not (step S 6 ). In step S 6 , when it is determined that the entire data is not received (step S 6 ; No), it returns to step S 1  and repeats the processing of steps S 1  through S 5 .  
         [0063]     In step S 6 , when it is determined that the entire data is received (step S 6 ; Yes), the intermediate data is analyzed at the rasterization processing unit  30 , and a bit map data is generated from the intermediate data (step S 7 ). Subsequently, print output processing is conducted for the bit map data generated in step S 7  at the printing unit  31  (step S 8 ), and the print processing is completed.  
         [0064]     Next, with reference to flowchart of  FIG. 5 , the color/monochrome processing (step S 4  of  FIG. 4 ) is described in detail.  
         [0065]     First of all, at the color/monochrome state transition unit  28 , it is determined whether the current state transition within the page is [Only RGB] or not (step S 10 ). In step S 10 , when it is determined that the current state transition is [Only RGB] (step S 10 ; Yes), it is regarded that the page has already been assigned a command for color, and color printing is conducted. Therefore, color/monochrome determination processing of step S 11  is not conducted thereinafter within that page, and moves on to step S 5  of  FIG. 4 .  
         [0066]     In step S 10 , when it is determined that the current state transition is other than [Only RGB] (step S 10 ; No), color/monochrome determination processing described later ( FIG. 6 ) is conducted (step S 11 ), and the color/monochrome processing is completed.  
         [0067]     Next, with reference to flowchart of  FIG. 6 , the color/monochrome determination processing (step S 11  of  FIG. 5 ) is described in detail.  
         [0068]     In the color/monochrome determination processing, each of the following processing is executed according to a command relating to color space of PDL, however, no processing is executed in case it is a command of other type. An example of command relating to color space is shown in Tables 1 and 2. As shown in Tables 1 and 2, concerning commands relating to color space, there are two types of commands, a command to set the color space, and a command to observe the color space. As shown in Table 1, as for commands to set the color space, there is color space set command, pen information set command, and brush information set command. Additionally, as shown in Table 2, as for commands to observe the color space, there is image pattern information set command and image information set command.  
                           TABLE 1                                   Command to               Set Color           Space   Object                           Color Space   Set color space for pen information, brush           Set Command   information, image pattern information, and               image information.               Concerning color space, assigning RGB/Gray,               and setting palette data, which can be used               within image pattern information or image               information, can be conducted.           Pen   Set pen information.           Information   A command to set colors when drawing vector           Set Command   or text.               Color of pen can be assigned by RGB/Gray, or               by pattern assigned by image pattern               information.           Brush   Set brush information.           Information   Brush is a command to set colors to fill           Set Command   vector, text, or image.               Color of brush can be assigned by RGB/Gray,               or by pattern assigned by image pattern               information.                      
 
         [0069]    
       
         
               
               
               
             
           
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                   
               
               
                   
                 Command to 
                   
               
               
                   
                 Observe Color 
               
               
                   
                 Space 
                 Object 
               
               
                   
                   
               
             
             
               
                   
                 Image Pattern 
                 Set image pattern information. 
               
               
                   
                 Information 
                 Image pattern information can be used within 
               
               
                   
                 Set Command 
                 pen information and brush information. 
               
               
                   
                   
                 Set information on whether size of image 
               
               
                   
                   
                 pattern, bit depth, or image pattern is 
               
               
                   
                   
                 assigned directly or by palette, and 
               
               
                   
                   
                 information of pattern ID. 
               
               
                   
                   
                 Image pattern is assigned within the color 
               
               
                   
                   
                 space assigned by the color space set 
               
               
                   
                   
                 command. 
               
               
                   
                   
                 Palette is also assigned by the color space 
               
               
                   
                   
                 set command. 
               
               
                   
                 Image 
                 Set image information. 
               
               
                   
                 Information 
                 Set information on whether size of image 
               
               
                   
                 Set Command 
                 data, bit depth, or image data is assigned 
               
               
                   
                   
                 directly or by palette. 
               
               
                   
                   
               
             
          
         
       
     
         [0070]     First of all, it is determined whether the command of PDL is color space set command or not (step S 20 ). In step S 20 , when it is determined that the command of PDL is color space set command (step S 20 ; Yes), processing of color space set command ( FIG. 7 ) described later is conducted (step S 21 ), and the color/monochrome determination processing is completed.  
         [0071]     In step S 20 , when it is determined that the command of PDL is not color space set command (step S 20 ; No), it is determined whether the command of PDL is a pen information set command (step S 22 ). In step S 22 , when it is determined that the command of PDL is a pen information set command (step S 22 ; Yes), processing of pen information set command ( FIG. 8 ) described later is conducted (step S 23 ), and the color/monochrome determination processing is completed.  
         [0072]     In step S 22 , when it is determined that the command of PDL is not pen information set command (step S 22 ; No), it is determined whether the command of PDL is brush information set command (step S 24 ). In step S 24 , when it is determined that the command of PDL is brush information set command (step S 24 ; Yes), processing of brush information set command ( FIG. 8 ) described later is conducted (step S 25 ), and the color/monochrome determination processing is completed.  
         [0073]     In step S 24 , when it is determined that the command of PDL is not brush information set command (step S 24 ; No), it is determined whether the command of PDL is image pattern information set command (step S 26 ). In step S 26 , when it is determined that the command of PDL is image pattern information set command (step S 26 ; Yes), processing of image pattern information set command ( FIG. 9 ) described later is conducted (step S 27 ), and the color/monochrome determination processing is completed.  
         [0074]     In step S 26 , when it is determined that the command of PDL is not image pattern information set command (step S 26 ; No), it is determined whether the command of PDL is image information set command (step S 28 ). In step S 28 , when it is determined that the command of PDL is image information set command (step S 28 ; Yes), processing of image information set command ( FIG. 9 ) described later is conducted (step S 29 ), and the color/monochrome determination processing is completed.  
         [0075]     In step S 28 , when it is determined that the command of PDL is not image information set command (step S 28 ; No), the color/monochrome determination processing is completed.  
         [0076]     Next, with reference to flowchart of  FIG. 7 , processing of color space set command (step S 21  of  FIG. 6 ) is described in detail.  
         [0077]     First of all, it is determined whether the color space assigned by the color space set command is RGB or not (step S 30 ). In step S 30 , when it is determined that the color space is not RGB (step S 30 ; No), the state transition is set to [Gray] (step S 31 ), and the processing of color space set command is completed.  
         [0078]     In step S 30 , when it is determined that the color space is RGB (step S 30 ; Yes), it is determined whether palette is assigned or not (step S 32 ). In step S 32 , when it is determined that palette is not assigned (step S 32 ; No), the state transition is set to [RGB] (step S 33 ), and the processing of color space set command is completed.  
         [0079]     In step S 32 , when it is determined that palette is assigned (step S 32 ; Yes), content of palette data is analyzed, and it is determined whether the content of palette data is RGB or not (step S 34 ). In step S 34 , when it is determined that the content of palette data is RGB (step S 34 ; Yes), the state transition is set to [Only RGB] (step S 35 ), and the processing of color space set command is completed.  
         [0080]     In step S 34 , when it is determined that the content of palette data is not RGB but mix gray (step S 34 ; No), after the original color space set command is stored (step S 36 ), palette data is converted to gray and the color space set command is converted to a command which assigns gray (step S 37 ). Subsequently, the state transition is set to [RGB→Gray] (step S 38 ), and the processing of color space set command is completed. Here, mix gray is a data, whose content is gray although the assigned color space is RGB, such as [255,255,255], for example. In such case, by converting the data to [255] and by setting command that assigns gray, color/monochrome determination processing is conducted.  
         [0081]      FIG. 10  shows an example of color space set commands. As shown in  FIG. 10 , in case a palette is assigned, even when the color space is RGB, palette data is converted to gray ([0 255]) and the color space command is converted to a command which assigns gray, when content of the palette data is mix gray.  
         [0082]     Next, with reference to flowchart of  FIG. 8 , processing of pen information set command (step S 23  of  FIG. 6 ) and processing of brush information set command (step S 25  of  FIG. 6 ) will be described in detail. Since the two processing are similar, the same flowchart is used for description.  
         [0083]     First of all, it is determined whether RGB is assigned or not in the pen information set command or the brush information set command (step S 40 ). In step S 40 , when it is determined that RGB is not assigned (step S 40 ; No), the state transition is set to [Gray] (step S 41 ), and the processing for pen information/brush information set command is completed.  
         [0084]     In step S 40 , when it is determined that RGB is assigned (step S 40 ; Yes), it is determined whether the content of the assigned data is RGB or not (step S 42 ). In step S 42 , when it is determined that the content of the assigned data is RGB (step S 42 ; Yes), the state transition is set to [Only RGB] (step S 43 ), and the processing for pen information/brush information set command is completed.  
         [0085]     In step S 42 , when it is determined that the content of assigned data is not RGB but mix gray (step S 42 ; No), the data is converted to gray and the command is converted to a command that assigns gray (step S 44 ). Subsequently, the state transition is set to [ RGB→Gray] (step S 45 ), and the processing for pen information/brush information set command is completed.  
         [0086]     Next, with reference to flowchart of  FIG. 9 , processing of image pattern information set command (step S 27  of  FIG. 6 ) and processing of image information set command (step S 29  of  FIG. 6 ) is described in detail. Since the two processing are similar, the same flowchart is used for description.  
         [0087]     Within image pattern information set command and image information set command, pattern and image can be assigned directly (direct assignment.) (in case of bit map data for example), or be assigned using a palette which is assigned by color space set command, respectively.  
         [0088]     First of all, it is determined whether the image pattern information set command or the image information set command is assigned directly or not (step S 50 ). In step S 50 , when it is determined that it is not direct assignment (step S 50 ; No), the color/monochrome determination processing has already been conducted by the color space set command. Therefore, nothing is further conducted, and moves on to step S 5  of  FIG. 4 .  
         [0089]     In step S 50 , when it is determined that it is direct assignment (step S 50 ; Yes), it is determined whether the current state transition is [ RGB→Gray] or not (step S 51 ). In step S 51 , when it is determined that the current state transition is not [ RGB→Gray] (step S 51 ; No), it moves on to step S 53 , described later.  
         [0090]     In step S 51 , when it is determined that the current state transition is [ RGB→Gray] (step S 51 ; Yes), a processing to turn back the color space set command is conducted (step S 52 ). The reason to turn back the color space set command is as follows. In case of a direct assignment, data is directly assigned within the color space assigned by the color space set command. Therefore, when the color space is changed from RGB to Gray before processing of the image pattern information set command or the image information set command has been conducted, only one third of the actual data amount is read out, in case the color space is changed to Gray although the actual data is RGB. As a result, the data left unread will be read as a command in the following command analysis. However, since this is not a command of PDL, it will result in data error.  
         [0091]     Subsequently, it is determined whether direct data is RGB or not (step S 53 ). In step S 53 , when it is determined that the direct data is RGB (step S 53 ; Yes), the state transition is set to [Only RGB] (step S 54 ), and the processing of image pattern information/image information set command is completed.  
         [0092]     In step S 53 , when it is determined that the direct data is not RGB (step S 53 ; No), the direct data is converted to gray and the command is converted to a command that assigns gray (step S 55 ). Subsequently, the state transition is set to [Gray] (step S 56 ), and the processing of image pattern information/image information set command is completed.  
         [0093]     As aforementioned, according to the image forming device  2  of the present embodiment, by determining whether a printing is particularly a color printing or particularly a monochrome printing based on a PDL, and changing command of the PDL to a command for monochrome printing in case it is monochrome printing, memory area used can be decreased compared to conducting determination processing after rasterization. Therefore, processing speed can be increased and determination accuracy can be improved.  
         [0094]     Particularly, by omitting determination within the page once it is determined as a color printing in that page, processing speed can be further increased.  
         [0095]     Here, the description in the aforementioned embodiment can be modified as long as it does not deviate the scope of the present invention.  
         [0096]     For example, in the aforementioned embodiment, processing of steps S 2  through S 4  in  FIG. 4  were conducted within image forming device  2 , which received print data from PC  1 . However, these processing can be conducted within the PC  1 . That is, PC  1  may be provided with the functions of the print controlling device of the present invention. In particular, processing or steps S 2  through S 4  in  FIG. 4  are conducted within the PC  1 , and processing result of color/monochrome processing in step S 4  is sent to the image forming device  2 .  
         [0097]     The present U.S. patent application claims a priority under the Paris Convention of Japanese patent application No. 2005-375359 filed on Dec. 27, 2005, and shall be a basis of correction of an incorrect translation.