JP2015116703A - Image formation device and image formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform load dispersion of a rendering process and an object coupling process.SOLUTION: An image formation device performs a coupling process in which a plurality of objects contained in print data are coupled into a single object. Based on a content of the print data, the number of objects which are subjected to the coupling process is decided. Based on the number of objects that has been decided, a plurality of objects contained in the print data are coupled into a single object.

Description

  The present invention relates to an image forming apparatus and an image forming method for generating intermediate data from PDL (Page Description Language) data and rendering the intermediate data to generate a bitmap image.

  With recent diversification of application software and OS, and performance improvement of the host PC, print drawing commands have become complicated, and the load of drawing processing in the image forming apparatus has increased. The image forming apparatus includes an intermediate data generation unit that generates intermediate data called a display list from PDL data received from an external device, and a rendering processing unit that draws a bitmap image from the generated intermediate data. This intermediate data includes edge data (also simply referred to as an edge) indicating the outline of each object to be rendered. A bitmap image is drawn by processing the intermediate data including the edge data by the rendering processing unit.

  When the PDL data includes a large number of objects having complicated contour shapes, a large number of edges are generated. As a result, the load on the rendering processing unit increases, and the processing time may become longer.

  On the other hand, Patent Document 1 determines whether or not a plurality of edges included in the intermediate data satisfy the joining condition, and if the joining condition is satisfied, joins the plurality of edges to one edge and creates new intermediate data. The technique which produces | generates is disclosed. By performing such edge combination processing, new intermediate data with a reduced number of edges is generated, and the load on the rendering processing unit is reduced.

JP 2006-350802 A

  In the method disclosed in Patent Document 1, a process of combining a plurality of edges is performed when an edge combining condition is satisfied. For this reason, depending on the data, a large amount of drawing commands satisfy the combining condition, and processing for combining a large amount of edges is performed, which places a load on the combining processing itself. As a result, the load on the rendering processing unit is reduced and the time of the rendering processing unit is increased, but the combining process takes a very long time, and the combining process is not performed by performing the combining process as the total printing time. It can be slower than the case.

  An image forming apparatus according to the present invention is an image forming apparatus that performs a combining process for combining a plurality of objects included in print data into one object, an acquisition unit that acquires print data, and the acquired A determining unit that determines the number of objects to be combined in the combining process based on the contents of the print data, and a plurality of objects included in the acquired print data based on the determined number of objects A coupling means for coupling to the object.

  According to the present invention, it is possible to perform load distribution between the combining process and the rendering process.

1 is a hardware configuration diagram showing an embodiment of a printing system including an image forming apparatus in an embodiment of the present invention. FIG. 2 is a software block diagram illustrating an embodiment of a print data control apparatus and an image forming apparatus in an embodiment of the present invention. It is a schematic diagram which shows the example of PDL data, intermediate data, and bitmap data in the embodiment of the present invention. It is a schematic diagram which shows an example of drawing total information in embodiment of this invention. It is a schematic diagram which shows the example of the input data to a joint process part, and the output data from a joint process part in embodiment of this invention. It is a figure which shows the case of a coupling | bonding excess in a coupling | bond part, and a coupling | bonding insufficient case. It is a figure which shows the flowchart regarding acquisition of drawing total information in embodiment of this invention. It is a figure which shows the flowchart regarding a series of drawing processes in embodiment of this invention. It is a figure which shows the flowchart regarding determination of the number of coupling | bonding in embodiment of this invention. It is a schematic diagram which shows an example of the drawing data regarding determination of the number of coupling | bonding in an embodiment of the present invention, an example of drawing total information, and a prediction formula used for prediction of processing time. It is a figure which shows the shortening effect of the processing time in embodiment of this invention.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the components described in this embodiment are merely examples, and are not intended to limit the scope of the present invention thereto.

  FIG. 1 is a block diagram illustrating an example of a printing system including an image forming apparatus on which a controller as an electronic component related to the present embodiment is mounted and peripheral devices. The printing system includes an image forming apparatus 100, a PC 170, a file server 180, and a LAN (Local Area Network) 160.

  The image forming apparatus 100 is connected to a PC 170 as a host computer and a file server 180 via a LAN such as Ethernet (registered trademark). The image forming apparatus 100 includes a reader unit 120, a printer unit 130, an operation unit 140, an image storage unit 150, and a controller unit 110 that controls these components. The controller unit 110 includes a CPU 112, a ROM 114, and a RAM 116.

  The CPU 112 performs overall control of the entire image forming apparatus 100 based on a program stored in the ROM 114 or other storage medium. For example, the controller unit 110 uses the CPU 112 to load a predetermined program for performing PDL analysis processing, combining processing, intermediate data generation processing, rendering processing, and the like. For rendering processing, dedicated hardware may be used.

  The printer unit 130 outputs the rendered image data (bitmap data) on paper. The operation unit 140 includes a keyboard for performing various print setting operations for performing image output processing, a liquid crystal panel for displaying operation buttons for performing image output settings, and the like. The image storage unit 150 can store print data such as image data, document data, and a printing apparatus control language (for example, ESC code, PDL). For example, the image storage unit 150 can store image data, document data, PDL data (page description language data) received from the PC 170 or the file server 180 via the LAN, and image data read by controlling the reader unit 120. .

  In this embodiment, the image forming apparatus 100 will be described using an MFP (Multi Function Printer) as an example. Of course, it goes without saying that a single function printer (SFP), a laser beam printer (LBP), or other printers may be used.

  The PC 170 includes a CPU 172, a ROM 174, and a RAM 176. The PC 170 generates a print job and transmits it to the file server 180.

  The file server 180 includes a data storage unit 185 and a print data control unit 187. The print data control unit 187 includes a CPU 181, a ROM 182, and a RAM 183.

  The print job generated by the PC 170 is transmitted to the file server 180 via the LAN. The print job is stored in the data storage unit 185 in the file server 180.

  FIG. 2 is a diagram illustrating an example of a software module diagram that operates in the print data control unit 187 of the file server and the controller unit 110 of the image forming apparatus 100 in the present embodiment.

  FIG. 2A is a module diagram of software that is stored in the ROM 182 of the print data control unit 187, developed into the RAM 183, and executed by the CPU 181 at the time of activation.

  The data control unit 240 controls processing from input to output of a print job stored in the data storage unit 185 by a method such as a function call or message communication.

  The PDL analysis units 241, 242, and 243 exist according to the type of PDL (for example, PostScript (registered trademark), PCL, and XPS) installed in the image forming apparatus 100. For example, when three types of PDL are mounted on the image forming apparatus 100, three PDL analysis units are provided. The PDL analysis units 241 to 243 read PDL data from the print job stored in the data storage unit 185 and execute analysis processing according to the control from the data control unit 240. The drawing total information generation unit 245 executes processing using the PDL command (drawing command) passed from the PDL analysis units 241 to 243 in accordance with the control from the data control unit 240, and performs edge / level / Count the number of elements such as fills. The drawing command is a command included in the PDL command. That is, in more detail, the drawing tabulation information generation unit 245 tabulates the number of elements constituting the intermediate data using the drawing command group included in the PDL command. The details of the difference between the PDL command and the drawing command will be described later. However, in the following cases where both are used as similar meanings, both may be written together as described above.

  The drawing total information generation unit 245 counts the number of the above elements for each object when generating intermediate data from the drawing command, and generates the counted number as the drawing total information 248. As described above, the drawing total information is a total of the number of elements constituting intermediate data of an object in a certain area. Details of the drawing total information will be described later. The generated drawing total information is stored in the RAM 183 on the file server 180 as a print job.

  A print job including drawing total information stored in the file server 180 is transmitted to the image forming apparatus 100 via the LAN. The user transmits a print job using the PC 170, and then performs user authentication using the ID in the image forming apparatus 100, and selects a print job for paper output. The selected print job is transmitted from the data storage unit 185 in the file server 180 to the image forming apparatus 100. In the present exemplary embodiment, a print job is stored in the file server 180 from the PC 170 as described above, and an example in which the user performs authentication in the image forming apparatus 100 and selects a print job will be described. It is not limited to. In other words, the print job may be transmitted from the PC 170 to the image forming apparatus 100 and the image forming apparatus 100 may generate the drawing total information. In other words, the image forming apparatus 100 and the file server 180 in the example of FIG. 1 may be integrated. Accordingly, the image forming apparatus 100 may acquire a print job obtained from an external apparatus, or may acquire a print job stored therein.

  FIG. 2B is a module diagram of software that is stored in the ROM 114 in the image forming apparatus 100, developed to the RAM 116 at the time of activation, and operated by the CPU 112. The job control unit 200 controls the output from the input of the print job stored in the data storage unit 185 by means such as a function call or message communication. The PDL analysis units 201, 202, and 203 exist according to the type of PDL (for example, PostScript (registered trademark), PCL, XPS, etc.) installed in the image forming apparatus 100. PDL analysis units 201 to 203 sequentially read PDL data from print jobs stored in the RAM 116 and execute analysis processing in accordance with control from the job control unit 200. The combination processing unit 205 determines the number of objects to be combined based on the contents of the print job. For example, the number of combined objects is determined for each print area using the drawing total information passed from the job control unit 200 and the PDL command (drawing command) passed from the PDL analysis unit 201-203. Further, the combination processing unit 205 executes object combination processing until the determined number of combinations is reached. Then, the combination processing unit 205 sends a drawing command indicating the combined object to the intermediate data generation unit 210. More specifically, the combination processing unit 205 generates intermediate data from the PDL command (drawing command) for the objects to be combined, and locally performs rendering processing (hereinafter referred to as pre-rendering). Then, a rendering command (that is, a rendering command for image data) indicating image data (bitmap data) including the object to be combined after being locally rendered is transmitted to the intermediate data generation unit. Details of the combining process will be described later. Note that the combination processing unit 205 directly sends a drawing command to the intermediate data generation unit 210 for objects that are not to be combined. That is, the combination processing unit is a local intermediate data generation unit and a local pre-rendering processing unit, and has a function of outputting a drawing command for drawing image data (bitmap data) after the pre-rendering processing. It can be said that there is.

  The intermediate data generation unit 210 generates intermediate data from the drawing command received from the combination processing unit 205 and stores it in the RAM 116 as a display list. The display list is a list format of elements constituting the intermediate data described above. When intermediate data for one page is generated, the rendering processing unit 220 reads the intermediate data from the RAM 116, executes the rendering process, and outputs image data (bitmap data). The output image data is stored in the image storage unit 150. Details of a series of processes related to the combination processing unit 205 and the intermediate data generation unit 210 by the image forming apparatus 100 will be described later.

  FIG. 3 shows a PDL command (drawing command) of an object obtained by analyzing PDL data, intermediate data obtained from the drawing command, and image data obtained by rendering the intermediate data according to the present embodiment. It is a schematic diagram.

  FIG. 3A is a schematic diagram showing a PDL command (drawing command) of a certain object obtained by analyzing PDL data output from an application, and an example of drawing the object on a page. A print job generated by the PC 170 includes PDL data. For example, a PDL command 300 as shown in FIG. 3A is obtained from the PDL data by analysis by the PDL analysis unit. As shown in FIG. 3A, the PDL command includes a drawing command group such as designation of a canvas to be drawn, the start point, the coordinate position of each point sequence, the color value, and the stroke width. The intermediate data generation unit generates intermediate data from the drawing command group. A PDL command 300 (that is, a drawing command group) in FIG. 3A is a command intended to draw the page view 310 in FIG.

  FIG. 3B is a diagram illustrating intermediate data generated by the intermediate data generation unit using the PDL command 300 illustrated in FIG. The intermediate data shown in FIG. 3B includes edge data 330 having drawing object outline information, level data 331 having drawing object overlap information, and fill data 332 having drawing object fill information. . Data corresponding to each object has a list configuration (display list) referred to in the order of edge, level, and fill. The rendering processing unit performs the rendering process by tracing the intermediate data in order from the edge.

  FIG. 3C is a diagram illustrating the image data after being rendered by the rendering processing unit from the intermediate data (display list) illustrated in FIG. As shown in FIG. 3C, the bitmap data 320 of the drawing object is generated after the rendering process is executed.

  FIG. 4 is a schematic diagram showing an example of drawing total information related to the present embodiment. The drawing total information is generated by the drawing total information generation unit 245 of the file server 180. The drawing total information is used in the combination processing unit 205 in order to predict the processing time in the rendering processing unit 220 and the combination processing unit 205 of the image forming apparatus 100. An example of processing time prediction will be described later. The drawing total information is a value obtained by totaling information on each element constituting intermediate data such as edges, levels, and fills in the intermediate data format described with reference to FIG. 3B for each area (for example, for each band or block). . Specifically, the information is as shown in FIG. For example, the total number of edges is a value describing the number of edges of each object included in each band or block. The drawing total information generation unit 245 can estimate the number of edges, for example, by interpreting a drawing command, tracking the coordinate position of a point, or counting the number of rectangles. Similarly, the number of elements of other elements constituting the intermediate data can be estimated without actually generating the intermediate data.

  FIG. 5 is a schematic diagram illustrating an example of an input / output result in the combination processing unit 205 according to the present embodiment. The combination processing unit 205 of the image forming apparatus 100 combines objects drawn by PDL commands issued by the PDL analysis units 201 to 203 in order to shorten the processing time of the rendering processing unit 220. The PDL command is a command including a drawing command group as shown in FIG. In the present embodiment, it is assumed that a plurality of drawing commands are included in one PDL command, and one object is drawn by a group of drawing commands included in one PDL command. This drawn object is referred to as a drawing object.

  FIG. 5A is a schematic diagram illustrating an example of a drawing object drawn by a PDL command input to the combination processing unit 205. In the example of FIG. 5A, five rectangular objects are included in a predetermined area. That is, in the example of FIG. 5A, five PDL commands as shown in FIG. The combination processing unit 205 determines the number of elements that will constitute the intermediate data with reference to the drawing total information of the area corresponding to the PDL command. Using this result, the combination processing unit 205 performs a combination process. In the example of FIG. 5A, the combination processing unit 205 determines that five rectangular objects are included from the input PDL command, and uses 10 edges, 5 levels, 5 fills as the number of elements of intermediate data from the drawing total information. To include the information.

  When there are a large number of drawing objects in a drawing area, the time required for rendering increases exponentially. Therefore, in order to shorten the processing time of the rendering processing unit 220, it is possible to reduce the time required for the rendering process by combining drawing objects, in other words, by performing the pre-rendering process locally. .

  FIG. 5B is a schematic diagram illustrating an example of a result of combining the drawing objects in FIG. 5A as one drawing object. The number of elements of the intermediate data to be generated is reduced by pre-rendering five drawing objects in the combination processing unit 205 and collecting them into a drawing object including one image. In other words, the combination processing unit 205 generates intermediate data from PDL commands indicating five drawing objects. The generated intermediate data includes information of 10 edges, 5 levels, and 5 fills as shown in FIG. Then, the combination processing unit 205 pre-renders the generated intermediate data to generate bitmap data including five drawing objects. The combination processing unit 205 generates a drawing command for drawing bitmap data including these five drawing objects. Then, the combination processing unit 205 outputs a drawing command for drawing the generated bitmap image data to the intermediate data generating unit 210 instead of the PDL command (drawing command group) indicating the five drawing objects. The intermediate data generated by the intermediate data generation unit 210 from the rendering command output in this way is 2 edges, 1 level, and 1 fill as shown in FIG. That is, the intermediate data shown in FIG. 5B has a smaller number of elements constituting the intermediate data than the intermediate data shown in FIG. As described above, the drawing information in the intermediate data is reduced by the combining process, so that the processing time of the rendering processing unit 220 can be shortened.

  However, if the number of connections in the dark clouds is increased, the connection process may take too long. As described above, the combining process can be said to be a local rendering process. In rendering processing, as the number of elements of intermediate data increases, the time required for rendering processing increases exponentially. Here, increasing the number of combinations increases the number of elements of intermediate data to be pre-rendered in the combination processing unit, so that a situation occurs in which the combination processing (that is, pre-rendering processing) takes too much time. .

  FIG. 6 is a schematic diagram illustrating a state of insufficient coupling and excessive coupling in the coupling processing unit. FIG. 6A is a schematic diagram illustrating an example of a drawing object drawn by a PDL command input to the combination processing unit 205. FIG. 6A shows an example in which twelve polygonal objects represented by twelve PDL commands are locally densely arranged. That is, the PDL command input to the combination processing unit is a command for drawing a drawing object as shown in FIG. For such a group of drawing objects that are locally crowded, a combining process (pre-rendering process) is performed by the combining processing unit 205 in order to shorten the processing time of the rendering processing unit 220.

  FIG. 6B is a schematic diagram showing a state where the 12 drawing objects of FIG. 6A are combined into one drawing object. In practice, the combination processing unit 205 generates intermediate data of a local area based on the rendering command obtained from the PDL command as described above, and pre-renders to generate one bitmap data. Then, the combination processing unit 205 generates a drawing command for drawing the bitmap data and outputs the drawing command to the intermediate data generation unit 210. Such processing is drawing object combining processing. In the following, in order to simplify the description, such a combination process may be described with a conceptual expression of simply combining a plurality of drawing objects into one drawing object. The intermediate data generation unit 210 generates intermediate data from the rendering command output from the combination processing unit 205, and the rendering processing unit 220 performs processing for rendering the intermediate data.

  As shown in FIG. 6B, when all drawing objects are combined as a combination target, the processing time of the rendering processing unit 220 is greatly shortened, but the pre-rendering processing time in the combining processing unit 205 is increased. As a result, the processing time of the software operating on the CPU 112 of the image forming apparatus 100 may increase due to the combining process.

  FIG. 6C is a schematic diagram showing a state in which two drawing objects in FIG. 6A are combined into one drawing object. In this way, when a small number of drawing objects are combined, the processing time of the combining processing unit 205 is short. However, the processing time of the rendering processing unit 220 is not shortened, and the processing time of the software operating on the CPU 112 of the image forming apparatus 100 is very long due to the rendering process.

  FIG. 6D is a diagram illustrating an example of processing times for the excessive coupling case and the unexpected coupling case. In FIG. 6A, the drawing object is described as 12. However, FIG. 6D illustrates the processing time of software operating on the CPU 112 of the image forming apparatus 100 when the number of drawing objects is 1024 × 1024. FIG. The excessive combination case (corresponding to FIG. 6B) is when all the 1024 × 1024 drawing objects are combined by the combination processing unit. In this case, the rendering processing time is as short as 0.5 seconds, but the combining processing time is very long as 1984.2 seconds. In the case of insufficient combination (corresponding to FIG. 6C), the time when 1024 × 1024 drawing objects are combined in units of 10 and then converted to intermediate data, and the rendering processing unit 220 performs the rendering process. It is. In this case, the combining processing time is as short as 12.3 seconds, but the rendering processing time is very long as 762.2 seconds. Since the time taken for the sorting process in the rendering process is high, the processing time tends to increase exponentially as the edge data increases. Therefore, in the present embodiment, by adjusting the number of drawing objects, insufficient and excessive combinations are avoided, and the processing time load of the combination processing unit 205 and the rendering processing unit 220 is distributed.

  FIG. 7 is a flowchart showing an example of the operation of the software module of FIG. 2A, which is software operating on the CPU 181 in the print data control unit 187 of the file server 180. First, in step S701, the data control unit 240 included in the print data control unit reads the PDL data stored in the data storage unit 185, and executes an analysis processing request to the corresponding PDL analysis unit. Next, in step S702, the PDL analysis units 241, 242, and 243 analyze the PDL command as shown in FIG. 3A obtained from the PDL data. In step S703, the PDL analysis units 241 to 243 analyze the PDL command, issue a drawing command, and notify the drawing total information generation unit 245 of the drawing command. In step S704, the drawing total information generation unit 245 estimates the number of elements of intermediate data issued by the drawing command. For example, the number of elements of the intermediate data as shown in FIG. 3B is estimated from the PDL command (drawing command) shown in FIG. In step S705, the estimated number of elements of intermediate data is totaled. In step S706, the drawing total information generation unit 245 generates drawing total information obtained by totaling the number of elements of the intermediate data for each area. The processes in steps S702 to S706 are repeated until the PDL command analysis is completed. When the analysis of all PDL commands is completed, the process advances to step S707, and the print data control unit 187 includes the drawing total information 248 in the print job and stores it in the data storage unit 185.

  FIG. 8 is a flowchart showing an operation of the drawing process of an example of the software module of FIG. 2B that operates on the CPU 112 in the controller unit 110 of the image forming apparatus 100. First, in step S <b> 801, the job control unit 200 stores the print job received from the file server 180 in the RAM 116. The print job includes PDL data and drawing total information. In step S802, the PDL analysis units 201 to 203 analyze the PDL data included in the print job.

  In step S803, the PDL analysis unit 201-203 issues a page start command and performs PDL analysis of the first page. In step S804, the combination processing unit 205 determines the number of drawing objects combined by the combination processing unit in a certain area. In step S804, the combination processing unit 205 reads the drawing total information, performs time prediction of rendering processing, and determines the number of drawing objects to be combined. The process for determining the number of connections in step S804 will be described later with reference to FIGS.

  In step S805, the PDL analysis unit 201-203 analyzes the PDL command in the corresponding page of the PDL data. As described above, one drawing object is drawn from one PDL command. In step S805, the subsequent processing is performed using one PDL command as a processing unit among a plurality of PDL commands corresponding to the page.

  In step S806, the PDL analysis units 201 to 203 issue a drawing command included in the PDL command, and notify the combination processing unit 205 of the drawing command. In step S807, the combination processing unit 205 determines whether the notified drawing command satisfies the combination condition. The combination condition is determined by the position and attribute of the drawing object drawn by the drawing command and the position and attribute of the drawing object drawn by the drawing command before and after the drawing command. For example, it is determined that the joining condition is satisfied when the positions of the drawing objects overlap by a certain amount or when the attributes of the drawing objects are the same. The coupling condition is not limited to this example, and an arbitrary condition can be set.

  If it is determined in step S807 that the join condition is not satisfied, the process proceeds to step S813, and the intermediate data generation unit 210 starts processing to generate intermediate data. If it is determined in step S807 that the join condition is satisfied, the process advances to step S808, and the join processing unit 205 determines whether the number of drawing objects satisfying the join condition is equal to or less than the join number. More specifically, the combination processing unit 205 determines whether or not the number of drawing objects satisfying the combination condition is equal to or less than the number of combinations determined in step S804 corresponding to the current processing target area. In this embodiment, since the number of connections is determined for each predetermined area, the determination in step S808 is also performed for each predetermined area.

  In step S808, if the number of objects satisfying the join condition is greater than the number of joins, the process proceeds to step S813, where the intermediate data generation unit 210 starts processing for generating elements included in the intermediate data. On the other hand, if the number of objects satisfying the join condition is equal to or less than the join number in step S808, the process proceeds to step S809, and the join processing unit 205 sets the draw object drawn by the draw command issued in step S806 as the object to be joined. And decide.

  In step S810, the combination processing unit 205 determines whether the number of objects to be combined is the number of connections determined in step S804. When the number of objects to be combined is the determined number of objects to be combined, in step S812, the combining processing unit 205 performs a combining process on the objects to be combined. If the number of objects to be combined is not determined in step S810, the combination processing unit 205 determines in step S811 whether the PDL command currently being processed is the last PDL command. Here, since the combination process is performed for each area, it is determined whether it is the last PDL command in the area to be processed. If it is the last PDL command, the process proceeds to step S812, and the combining process is performed using the objects to be combined so far. If it is not the last PDL command, the process returns to step S805.

  In step S812, the combination processing unit 205 performs combination processing of objects to be processed. That is, each of a plurality of objects to be processed is pre-rendered to generate one bitmap data. Then, a rendering command indicating the generated bitmap data is output to the intermediate data generation unit 210.

  A specific example will be given to supplement the processing from step S808 to step S812. For example, assume that the number of connections determined in step S804 for a certain region is 100. This means that when 100 drawing objects are combined in this area, the time required for the combining process and the time required for the rendering process are well balanced. At this time, it is assumed that there are 300 drawing objects in this area. Further, it is assumed that all these 300 objects satisfy the coupling condition. In this case, the first to 100th drawing objects are combined into one drawing object. The next 101st to 200th drawing objects are similarly combined into one drawing object.

  In step S813, the intermediate data generation unit 210 generates intermediate data based on the received drawing command. That is, an element included in the intermediate data is generated.

  Steps S805 to S813 are repeated until all the PDL commands of the corresponding page are analyzed. When all the PDL commands of the corresponding page are analyzed and the elements included in the intermediate data are generated, the process advances to step S813 to close the intermediate data. In step S814, the rendering processing unit 220 reads intermediate data from the RAM 116, renders the intermediate data, and outputs an image in step S815. The intermediate data is generated for all pages, and the processing from S803 to S816 is repeated until the rendering processing is performed, and the series of processing ends.

  FIG. 9 is a flowchart illustrating the operation of the combination processing unit 205 that operates on the CPU 112 in the controller unit 110 of the image forming apparatus 100, and illustrates the process of determining the number of connections from the drawing total information in S804. In step S <b> 901, the combination processing unit 205 reads drawing total information passed from the job control unit 200. Next, the processing proceeds to step S902, where the band that is the head region is set as a region for which the rendering processing time is predicted and the number of connections is determined. Hereinafter, the region is referred to as a band.

  In the present embodiment, as shown in the schematic diagram of FIG. 10A, drawing total information is generated in band units. Therefore, the number of couplings is also determined for each band. That is, rendering time prediction processing is performed from the first band 1 to band 2 and band 3 in order from the drawing total information of each band. Details will be described later.

  In step S903, the combination processing unit 205 sets the number of combinations to an initial value. The initial value may be any value, but in the present embodiment, since the process of increasing the number of connections is performed in the subsequent processes, a small value such as 2 or 5 is used. Moreover, 0 which shows not couple | bonding may be sufficient. The combination processing unit 205 updates the received drawing total information with the number of elements of the reduced intermediate data estimated when the combination processing unit 205 combines the drawing objects according to the initial number of combinations. For example, when the number of combined initial values is 5, the estimated number of elements of the intermediate data included in the received drawing total information is reduced according to the combined number. As described above, this process estimates the drawing object to be combined that will be combined from the drawing instruction of the PDL command, and estimates the number of elements of the intermediate data remaining when the drawing object to be combined is combined. To do. The combination processing unit 205 updates the received drawing total information using the decreased value.

  In step S904, the combination processing unit 205 predicts the rendering processing time from the updated drawing total information in the target band. In step S905, the combination processing unit 205 determines whether the rendering prediction time is N minutes or longer. N can arbitrarily set the time that the user thinks that the processing takes too much time if the estimated rendering time exceeds this value. For example, suppose N is 3.

  This will be described using a specific example. When FIG. 10A is an example of input data, in step S905, the drawing total information of band 1 is read as FIG. 10B. Since there is only one rectangular object in band 1, drawing total information such as 2 for the total number of edges is described. FIG. 10E shows a prediction formula used for prediction of rendering time from the drawing total information performed in step S904. The rendering time is predicted using each parameter of the drawing total information. “A” to “n” in FIG. 10E are predetermined coefficients. EdgeCount corresponds to the total number of edges, VectorEdge corresponds to the type of edge, SegmentHeight corresponds to the total number of edge lengths, SegmentCount corresponds to the number of point sequences, and EdgeDensity corresponds to the edge density. CompositeLevel corresponds to the total number of levels, and LevelDensity corresponds to the level density. FillCount corresponds to the total number of fills, RotateImage corresponds to the total number of rotated images, and NoRotateImage corresponds to the total number of non-rotated images. CompositeImage corresponds to the total number of composite images, NoCompositeImage corresponds to the total number of non-composite images, and GradImage corresponds to the total number of gradations. C is a constant. Whether or not the predicted time calculated by this formula is N minutes or more is determined in the process of step S905.

  In step S905, the combination processing unit 205 determines whether the predicted rendering time is N minutes or longer. If it is less than or equal to N minutes, it is not band data that imposes a load on the rendering process, so the process proceeds to step S913 as it is, and the process for all bands is repeated. In step S905, if the estimated rendering processing time is N minutes or more, the process proceeds to step S906, and the number of connections (= initial value) set in step S903 is increased by M (M is added to the number of connections). In step S907, the drawing total information is updated according to the increased number of connections. The update of the drawing total information is performed in the same manner as described in step S903. In step S908, the combination processing unit 205 predicts the rendering time based on the updated drawing total information.

  In step S909, the combination processing unit 205 determines whether the rendering prediction time obtained in step S909 is less than N minutes. If it is not less than N minutes, the rendering process time has not yet reached N minutes as the reference time, and there is a need for further combining. Therefore, the process proceeds to step S906 to increase the number of connections, and the processes from step S906 to step 909 are repeated again.

  If it is determined in step S909 that the predicted rendering time is less than N minutes, the process advances to step S910 to similarly predict the combination processing time for the combination processing unit 205 with the increased number of combinations. That is, the processing time when the rendering objects corresponding to the number of pulled-up connections is pre-rendered is predicted.

  Next, proceeding to step S911, the combination processing unit 205 calculates the predicted time of the rendering process performed in step S908 and the time obtained by adding N minutes as a reference value to the predicted time of the combination process performed in step S910. Compare. In step S911, when the prediction time of the rendering process is larger than the predicted time of the combination process + N, the combination process functions as an acceleration process because the cost of the combination process is low. Therefore, it progresses to step S912 and it determines with applying the number of coupling | bonding raised in S906 to the said band. In step S911, if the rendering processing prediction time is smaller than the joint processing prediction time + N, the cost of the joint processing is high and the joint processing itself becomes a bottleneck, so the number of joints is not increased, and the band is initially set. Use the value as it is. In step S913, it is determined whether there is a next band. If there is a next band, the target band is advanced in step S914. When the number of bonds has been calculated for all the bands, the series of processing ends.

  This will be specifically described below with reference to the example of FIG. When band 2 in FIG. 10A is an example of input data, the drawing total information of band 2 is read as FIG. 10C in step S901. Since a large number of polygonal objects exist in band 2, the total number of edges includes values such as 1,048,576. Since the band 2 includes a large amount of edges, the rendering time is predicted to be 3 minutes or more. Accordingly, the process proceeds to step S906 to start increasing the number of connections. In step S907, the drawing total information is updated by using the number of connections increased by M (for example, M = 100) as the initial value (for example, initial value = 10) of the number of connections set in step S903. In step S908, the combination processing unit 205 calculates the rendering time again based on the prediction formula of FIG. The number of connections is sequentially increased by M until the rendering prediction time becomes 3 minutes or less. FIG. 10D shows the drawing total information that finally becomes 3 minutes or less. The number of bonds at this time is 1210, and this number of bonds is applied to band 2.

  FIG. 11 is a specific example showing the effect in the present embodiment. As shown in FIG. 6 (d), the input excess data including 1024 × 1024 drawing objects has the combined number of 1024 × 1024 and the combined excessive case, and the combined insufficient case has the combined number of 10. And are comparison targets. In an appropriate combination case according to the present embodiment, the number of combinations is obtained as 1010, the processing time is load-balanced between the combination processing time and the rendering processing time, and a result of shortening the total time can be obtained.

<Other examples>
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, or the like) of the system or apparatus reads the program. It is a process to be executed.

Claims (11)

An image forming apparatus that performs a combination process for combining a plurality of objects included in print data into one object,
Acquisition means for acquiring print data;
Determining means for determining the number of objects to be combined in the combining process based on the content of the acquired print data;
A combining unit configured to combine a plurality of objects included in the acquired print data into one object based on the determined number of objects;
An image forming apparatus.   The image forming apparatus according to claim 1, further comprising a drawing unit that performs a drawing process using data obtained from the print data.   3. The determination unit according to claim 2, wherein the number of the objects is determined so that a time required for the drawing process performed by the drawing unit is shorter than a time required for the combining process performed by the combining unit. The image forming apparatus described. The acquisition means acquires page description language data described in a page description language as the print data,
The image forming apparatus includes:
Further comprising generating means for generating intermediate data based on a drawing command obtained from the page description language data;
The image forming apparatus according to claim 2, wherein the drawing unit performs a drawing process using the intermediate data generated by the generation unit.   The combining unit generates image data in which a plurality of objects are combined into one object based on a drawing command corresponding to the object to be combined, and outputs a drawing command for drawing the generated image data to the generating unit The image forming apparatus according to claim 4.   6. The determination unit according to claim 2, wherein the determination unit totals the number of elements constituting the intermediate data of the print data, and estimates the time required for the drawing process performed by the drawing unit from the total number of elements. The image forming apparatus according to claim 1.   The determining means is a combination performed by the combining means for a time required to generate image data in which a plurality of objects are combined into one object based on a drawing command corresponding to the number of objects to be combined with the print data. The image forming apparatus according to claim 2, wherein the time required for processing is estimated.   The image forming apparatus according to claim 1, wherein the combining unit performs a combining process for each print area included in the print data.   When the number of combined objects exceeds the number of objects determined by the determining means in the print area to be processed, the combining means combines the number of objects determined by the determining means into one object. 9. The image forming apparatus according to claim 8, further comprising a combination using another object in the print area to be processed. An image forming method for performing a combining process for combining a plurality of objects included in print data into one object,
An acquisition process for acquiring print data;
A determination step of determining the number of objects to be combined in the combining process based on the content of the acquired print data;
A combining step of combining a plurality of objects included in the acquired print data into one object based on the determined number of objects;
An image forming method comprising: A program for causing a computer to function as each unit of the image forming apparatus according to any one of claims 1 to 9.