JP6008115B2 - Printing device, printing system - Google Patents

Description

  The present invention relates to a printing apparatus using an image generation server and a printing system for the printing apparatus.

  Printing presses using digital image processing functions are spreading not only in general offices but also in fields that require higher image quality and productivity, such as publishing and commercial printing. This digital printing machine includes a printer controller that generates an electronic raster image from print data in PDL (Page Description Language) format, and an actual image on a paper medium based on the raster image generated by the printer controller. Is generally combined with a printer engine that outputs the final printed matter.

  There are PDL types such as PostScript (registered trademark), PDF (Portable Document Format), PCL (Printer Control Language) 6, XPS (XML Paper Specification), PPML (Personalized Print Markup Language), etc. Digital for commercial printing The printing machine has an imaging model that is basically the same as PostScript, which has been regarded as a language for high-definition printing, but also adds transparency effects and color space definitions as language specifications, further improving image expression and reproducibility. Reinforced PDF is used relatively often, and in particular, PPML that introduces the concept of reusable objects and the concept of memory caching and composition to cope with variable printing that prints while replacing part of the contents. Is also used relatively well.

  The raster image generation processing performed by the printer controller is called RIP (Raster Image Processing) processing. Generally, in a system that prints a full-color image or the like, many CPUs (Central Processing Units) are used in this RIP processing. Consumes computer resources. For this reason, the raster image generation speed may be lower than the print output speed of the printer engine depending on the balance between the capabilities of the printer controller and the printer engine, or the amount of data per page in the print data.

  For example, the capability (printing output speed) of the printer engine is generally expressed as 80 PPM (Pages Per Minute) in A4 size long side paper feeding, that is, 80 pages can be printed per minute. The In this example, if the printer controller can generate an A4 raster image of 80 pages or more per minute and supply it to the printer engine, the print output of the printer engine is maintained at the maximum speed. However, when the number of A4 raster images that the printer controller can supply to the printer engine per minute is less than 80 pages, the supply speed of the raster image becomes a bottleneck, and the maximum output speed of the printer engine cannot be maintained. Speed down will occur.

  The time required to generate a raster image for one page (hereinafter referred to as a page raster image) is the amount of data when an object placed on the page is developed into pixel data and the amount of calculation required at that time. It is greatly influenced by. There are various types of objects such as image objects digitized and captured by scanners and digital cameras, character objects (outline font data) represented by equations / curves / straight lines, and vector graphic objects. If there is a large amount of data when mapping as pixel representation data in raster image data for printers taking into account the printer resolution and its color space / color depth, etc. It takes a relatively long time to generate a raster image for the page. When it takes a long time to generate this raster image, it is impossible to supply an image corresponding to the printing output speed of the printer engine, and the possibility of the above-described speed reduction is increased. Therefore, a plurality of methods for preventing the occurrence of such speed reduction have been proposed.

  For example, Patent Document 1 describes a method for increasing the processing speed by incorporating hardware for performing parallel processing in a printing apparatus (Patent Document 1).

JP 2011-83914 A JP 2011-253337 A

  With the method disclosed in Patent Document 1, it is possible to increase the speed of the RIP process and to prevent the printer engine from speeding down as much as possible. However, since the raster image generation speed varies depending on the contents of the input print data, the ratio between the raster image generation speed and the print output speed of the printer engine is not always constant. When print data with a small amount of data that does not cause the printer engine speed reduction does not occur even if parallel processing is not performed, hardware resources that have excessive performance temporarily exist, and some of them An idle state will occur.

  Patent Document 2 discloses a method of performing parallel processing using a cloud server instead of built-in hardware. The cloud is an area where servers in a cloud computing environment are arranged. In a cloud computing environment, a user uses computer processing as a service via a network. In this method, a divided job is generated by dividing print data included in a print job, and RIP processing or the like (referred to as print data conversion processing in Patent Document 2) for a part of the divided job is requested to the cloud server. . However, in the method disclosed in Patent Document 2, parallel processing is performed using all available cloud servers. In this case, when print data with a small amount of data that does not cause a speed reduction of the printer engine does not occur even if parallel processing is not performed, parallel processing is performed using a cloud server even though it is unnecessary. It will be.

  In addition, when the cloud server is crowded, the processing capacity of the cloud server decreases. In a state where the processing capacity of the cloud server is reduced, the processing efficiency may be lower when the processing is requested from the cloud server than when the processing is not requested from the cloud server.

  The present invention solves the above-described problem. Only when necessary to maintain the speed of the printer engine, the image generation server is used efficiently, so that the printer engine can be used efficiently while using limited computer resources efficiently. An object of the present invention is to provide a printing apparatus and a printing system that can prevent the speed reduction of the printer as much as possible.

  The gist of the present invention for achieving the object lies in the inventions of the following items.

[1] A raster image generation unit that performs RIP processing for generating a raster image based on print data;
A printer engine that forms an image on paper based on the raster image generated by the raster image generation unit;
If it is determined that the raster image generation speed by the raster image generation unit is lower than the image formation speed of the printer engine, a part of the RIP processing for the print data is transferred to a predetermined image generation server on the network. A control unit that causes the printer engine to perform image formation based on the raster image generated by the raster image generation unit and the raster image received as a result of the substitution from the image generation server;
I have a,
The raster image generating unit expands a reuse object when generating a raster image of each page based on the print data, and then uses the image of the expanded reuse object based on the print data. Generate raster images for each page,
The control unit measures the time taken for the raster image generation unit to generate raster images for N (N is an integer equal to or greater than 1) pages using the expanded image of the reused object, and the measurement A printing apparatus that calculates a development speed per page based on a result .

  In the above invention, when it is determined that the generation speed of the raster image by the image generation unit is lower than the image formation speed of the printer engine, the RIP processing for the print data is performed by substituting a part of the RIP processing to the image generation server. Processing is performed in parallel by the image generation unit and the image generation server. As a result, the total raster image generation speed is increased, and the speed reduction of the printer engine can be prevented as much as possible. If the raster image generation speed of the printing apparatus alone (image generation unit alone) is not lower than the image formation speed of the printer engine, the RIP process is performed only by the printing apparatus. By using the image generation server only when it is necessary to maintain the speed of the printer engine, it is possible to prevent the speed reduction of the printer engine as much as possible while efficiently using limited computer resources.

[2] The printing apparatus according to [1], wherein the control unit determines a processing amount to be substituted for the image generation server according to a load state of the image generation server.

  In the above invention, the amount of RIP processing to be performed on behalf of the image generation server is determined according to the load status of the image generation server. When the image generation server is crowded, the processing capacity of the image generation server is reduced. Therefore, the requested processing amount is determined according to the processing capacity when requesting proxy for the RIP processing. Thereby, it is possible to request a processing amount corresponding to the processing capability of the image generation server.

[3] The control unit determines a load status of the image generation server based on a time from when the image generation server is requested to perform the RIP processing on behalf to when a raster image as a result of the proxy is received. The printing apparatus according to [2], which is characterized.

  In the above invention, the processing capacity (load status) of the image generation server is determined based on the time from when the predetermined amount of processing is requested to the image generation server until the processing result is received.

[4] The control unit determines a processing amount to be substituted for the image generation server, with an upper limit of RIP processing for the raster image generation by the raster image generation unit in time for image formation of the printer engine. The printing apparatus according to any one of [1] to [3].

In the above invention, the RIP processing for the time when the raster image generation by the image generation unit is in time for the image formation of the printer engine is performed by the image generation unit, and the RIP processing for the shortage (the time for the shortage) is set as the upper limit. The requested amount is determined in such a way as to act on behalf of. As a result, it is possible to minimize the occurrence of a printer engine speed reduction while using hardware resources of the printing apparatus as much as possible.
[5] A raster image generation unit that performs RIP processing for generating a raster image based on print data;
A printer engine that forms an image on paper based on the raster image generated by the raster image generation unit;
If it is determined that the raster image generation speed by the raster image generation unit is lower than the image formation speed of the printer engine, a part of the RIP processing for the print data is transferred to a predetermined image generation server on the network. A control unit that causes the printer engine to perform image formation based on the raster image generated by the raster image generation unit and the raster image received as a result of the substitution from the image generation server;
Have
The control unit determines a load state of the image generation server based on a time period from requesting the image generation server to perform the RIP processing on behalf to receiving a raster image of the substitution result, and the image generation server The processing amount to be substituted for the image generation server is determined according to the load status of
A printing apparatus characterized by that.
[6] A raster image generation unit that performs RIP processing for generating a raster image based on print data;
A printer engine that forms an image on paper based on the raster image generated by the raster image generation unit;
If it is determined that the raster image generation speed by the raster image generation unit is lower than the image formation speed of the printer engine, a part of the RIP processing for the print data is transferred to a predetermined image generation server on the network. A control unit that causes the printer engine to perform image formation based on the raster image generated by the raster image generation unit and the raster image received as a result of the substitution from the image generation server;
Have
The control unit determines a processing amount to be substituted for the image generation server, with an upper limit of RIP processing for the raster image generation by the raster image generation unit in time for image formation of the printer engine.
A printing apparatus characterized by that.

[ 7 ] The control unit sets a processing amount to be delegated to the image generation server so that the processing time in the image generation server is equal to the processing time in the raster image generation unit within a range not exceeding the upper limit. The printing apparatus according to [4] or [6] , wherein the printing apparatus is determined.

  In the above invention, if the total raster image generation speed is less than the image formation speed of the printer engine even if the image generation server performs RIP processing for a part of the print data, the process assigned to the image generation unit Each process is performed so that the time estimated to take (X) is equal to the time (Y) predicted to be assigned to the image generation server (X = Y). Determine the distribution amount. As a result, the fastest raster image can be generated.

[ 8 ] The printing apparatus according to any one of [1] to [ 7 ], wherein the control unit increases or decreases a processing amount to be substituted for the image generation server in units of pages.

[ 9 ] The printing apparatus according to any one of [1] to [ 8 ], wherein the print data is print data described in a page description language.

  In the above invention, the print data is print data described in a page description language. For example, it is composed of data in a format such as PPML, PDF, XPS.

[ 10 ] The printing apparatus according to any one of [1] to [ 9 ];
An image generation server that performs RIP processing requested by the printing apparatus and transmits a raster image as a result to the printing apparatus;
A printing system characterized by comprising:

  According to the printing apparatus and the printing system of the present invention, the image generation server is used only when it is necessary to maintain the speed of the printer engine, thereby reducing the speed of the printer engine while efficiently using limited computer resources. Can be prevented as much as possible.

It is explanatory drawing which shows an example of the printing system which concerns on embodiment of this invention. It is explanatory drawing which shows an example of the client system which concerns on embodiment of this invention. 1 is a block diagram showing a schematic configuration of a printing apparatus according to an embodiment of the present invention. It is a block diagram which shows schematic structure of the client terminal which concerns on embodiment of this invention. It is a block diagram which shows schematic structure of the network connection apparatus which concerns on embodiment of this invention. It is explanatory drawing which shows an example of the cloud service system which concerns on embodiment of this invention. It is a block diagram which shows schematic structure of the image generation server which concerns on embodiment of this invention. It is explanatory drawing which shows an example of a non-variable printed matter and a variable printed matter. It is explanatory drawing which shows the example which showed the description of PPML data simply. It is explanatory drawing which shows an example of the PDF data referred with PPML data of FIG. 1 is a block diagram illustrating a functional configuration of a printing system. It is a flowchart of a process when a printing system performs printing. FIG. 13 is a flowchart showing a continuation of the process of FIG. 12. 14 is a flowchart showing a continuation of the process of FIG. 13. It is explanatory drawing which shows the time chart at the time of performing parallel RIP processing.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a printing system 5 according to an embodiment of the present invention. The printing system 5 includes a plurality of client systems 7 (7A, 7B, 7C) and a cloud service system 6 connected via a WAN (Wide Area Network) 4. Note that any one of the client systems 7A, 7B, and 7C is indicated as the client system 7.

  The client system 7 performs printing based on the print data. When printing is performed, RIP processing is performed on the print data, and an image indicated by a raster image generated by the RIP processing is formed on a recording sheet by a printer engine 20 described later. In addition, the client system 7 performs a function of allowing the cloud service system 6 to perform RIP processing for a part of print data. By performing the RIP process performed by the client system 7 and the RIP process performed by the cloud service system 6 in parallel, the speed of the RIP process can be increased.

  FIG. 2 shows the configuration of the client system 7. The client system 7 includes a printing apparatus 10A, a printing apparatus 10B, a client terminal 40, and an inter-network connection device 50 connected via a LAN (Local Area Network) 3. In addition, when referring to any one of the printing apparatuses 10A and 10B, the printing apparatus 10 is indicated.

  The printing apparatus 10 has a function of executing a print job for forming and outputting an image related to print data sent from the client terminal 40 on a recording sheet.

  The client terminal 40 is a so-called PC (Personal Computer) terminal that plays a role of submitting a print job to the printing apparatus 10.

  The inter-network connection device 50 plays a role of connecting the cloud service system 6 and the client system 7 via the WAN 4 shown in FIG. When the printing apparatus 10 transmits / receives data to / from the cloud service system 6, the data passes through the network connection apparatus 50.

  FIG. 3 shows a schematic configuration of the printing apparatus 10 according to the embodiment of the present invention. The printing apparatus 10 has a CPU 11 that comprehensively controls the operation of the printing apparatus 10. The CPU 11 includes a flash memory 12, a RAM (Random Access Memory) 13, a hard disk device 14, an image generation unit 15, a network I / F (Interface) unit 16, a Video I / F 17, and a printer engine 20 through a system bus. It has.

  The CPU 11 is based on an OS (Operating System) program, and executes middleware, application programs, and the like.

  Various programs are stored in the flash memory 12, and each function of the printing apparatus 10 is realized by the CPU 11 executing various processes according to these programs. The flash memory 12 stores a program for the CPU 11 to execute a series of controls of the printing apparatus 10.

  The RAM 13 is used as a work memory for temporarily storing various data when the CPU 11 executes processing based on a program, an image memory for storing image data, and the like.

  The hard disk device 14 is a large-capacity nonvolatile storage device, and stores an OS program, various application programs, user information, image data, a print job (print data) received by the network I / F unit 16, and the like.

  The network I / F unit 16 performs a function of communicating data with the client terminal 40 and the like through the LAN 3 network. For example, when a print job (print data) is received from the client terminal 40 or when communication is performed with a device external to the client system 7, data is transmitted / received via the inter-network connection device 50.

  The image generation unit 15 performs processing such as image enlargement / reduction, rotation, rasterization processing (RIP processing) for converting print data into image data, image data compression / decompression processing, and the like. RIP processing is performed on the print data included in the print job received from the client terminal 40 to generate a raster image. Note that the print data is data in the PDL format, and is composed of PDF data and PPML data.

  The printer engine 20 has a function of forming an image indicated by the raster image on a recording sheet. Here, it has a recording paper transport device, a photosensitive drum, a charging device, a laser unit, a developing device, a transfer separation device, a cleaning device, and a fixing device, and forms an image by an electrophotographic process. It is configured as a so-called laser printer. Other methods may be used for the image forming process.

  The CPU 11, the flash memory 12, the RAM 13, the hard disk device 14, the image generation unit 15, the network I / F unit 16, and the Video I / F 17 are collectively referred to as a printer controller. The Video I / F 17 transmits and receives data between the printer controller and the printer engine 20. The raster image generated by the image generation unit 15 is sent to the printer engine 20 via the Video I / F 17.

  When the printing apparatus 10 receives a print job from the client terminal 40, the CPU 11 analyzes the print data included in the print job. In this analysis, the speed (starting with the raster image supply speed) from when the RIP process is started until the raster image is supplied to the printer engine 20 is checked. If the raster image supply speed is slower than the print output speed of the printer engine 20, it is determined that the maximum speed of the print output of the printer engine 20 is not maintained and a speed reduction occurs. When the CPU 11 determines that the speed reduction occurs, the CPU 11 substitutes the cloud service system 6 for RIP processing for a part of the print data. Since the RIP process performed by the cloud service system 6 is performed in parallel with the RIP process performed by the image processing unit 15, the proxy RIP process is hereinafter referred to as parallel RIP process. By generating the raster image in parallel in the image generation unit 15 and the cloud service system 6, it is possible to increase the speed of the RIP process and prevent the printer engine 20 from being slowed down. Further, the processing amount to be substituted (processing amount requested in the parallel RIP processing) is determined with the upper limit being RIP processing for the time when the raster image generation by the image generation unit 15 is not in time for image formation of the printer engine 20. In addition, the amount of processing is increased or decreased according to the processing capacity (load status or the like) of the cloud service system 6.

  Although not shown, the printing apparatus 10 includes an operation panel. The operation panel includes a display unit and an operation unit. The operation unit includes a switch unit such as a start button and a touch panel unit. The display unit is configured with a liquid crystal display (LCD) and the like, and fulfills a function of displaying various operation screens, setting screens, and the like. The touch panel unit is provided on the display unit. The touch panel unit detects a coordinate position on the display unit pressed by a touch pen or a finger, a flick operation, a drag operation, and the like. The user can give an instruction to execute the job to the printing apparatus 10 by operating the client terminal 40 or the operation panel.

  FIG. 4 shows a schematic configuration of the client terminal 40. The client terminal 40 has a CPU 41 that comprehensively controls the operation of the client terminal 40. The CPU 41 includes a RAM 42, a hard disk device 43, a network communication unit 44, an input I / F 45, a keyboard 46, a pointing device 47, an output I / F 48, and a monitor 49 through a system bus.

  The CPU 41 is based on the OS program, and executes middleware, application programs, and the like.

  The hard disk device 43 is a large-capacity nonvolatile storage device that stores various programs such as an OS program. The CPU 41 executes various processes according to these programs, thereby realizing each function of the client terminal 40. The

  The RAM 42 is used as a work memory for temporarily storing various data when the CPU 41 executes processing based on a program, an image memory for storing image data, and the like. In the embodiment, a program for creating a print job (print data) is loaded from the hard disk device 43 and executed by the CPU 41.

  The network communication unit 44 performs a function of communicating data between the printing apparatus 10 and the network connection apparatus 50 through the LAN 3.

  The keyboard 46 and the pointing device 47 (such as a mouse) serve as an operation unit, and the operation content received by the keyboard 46 and the pointing device 47 is transmitted to the CPU 41 by the input I / F 45.

  The monitor 49 is composed of a liquid crystal display or the like, and functions as a display unit that displays various operation screens and setting screens output from the output I / F 48.

  A program for creating a print job (print data) is usually a GUI (Graphical User Interface) -based program. The keyboard 46 and the pointing device 47 are used for image editing, and the contents can be confirmed on the monitor 49 at any time. It becomes.

  After the image editing is completed, a print job (print data) is generated, and the generated print job (print data) is transmitted to the printing apparatus 10 via the network communication unit 44.

  FIG. 5 shows a schematic configuration of the inter-network connection device 50. The inter-network connection device 50 has a CPU 51 that comprehensively controls the operation of the inter-network connection device 50. The CPU 51 includes a flash memory 52, a RAM 53, a first network I / F unit 54, and a second network I / F unit 55 through a system bus.

  The CPU 51 is based on the OS program and executes middleware, application programs, and the like.

  The flash memory 52 is a memory whose stored contents are not destroyed even when the power is turned off. Various programs are stored in the flash memory 52, and each function of the inter-network connection device 50 is realized by the CPU 51 executing various processes in accordance with these programs. In addition, it is used for storing various setting information of the inter-network connection device 50.

  The RAM 53 is used as a work memory that temporarily stores various data when the CPU 51 executes processing based on a program. Specifically, a network packet transfer program is loaded from the flash memory 52 to the RAM 53 and executed by the CPU 51. The RAM 53 also has routing information for packet transfer, and the program for network packet transfer is based on the routing information, and the first network I / F unit 54 or the second network I / F unit 55 The packet received from one of the packets is transferred to the other.

  The first network I / F unit 54 performs a function of communicating data between the printing apparatus 10 and the inter-network connection apparatus 50 through the LAN 3.

  The second network I / F unit 55 performs a function of communicating data with the cloud service system 6 (inter-network connection device 50 constituting the cloud service system 6 described later, see FIG. 6) through the WAN 4.

  FIG. 6 shows details of the cloud service system 6. The cloud service system 6 includes an image generation server 60A that functions as a cloud server, an image generation server 60B, and an inter-network connection device 50 connected via a LAN 3. Note that any one of the image generation servers 60A and 60B is indicated as the image generation server 60. The LAN 3 and the inter-network connection device 50 have the same configuration as that shown in FIG. 2, but are different from those shown in FIG.

  The image generation server 60 plays a role of generating a raster image. When a request (request job) for parallel RIP processing is received from the printing apparatus 10 via the inter-network connection apparatus 50, RIP processing is performed on the print data included in the received request job to generate a raster image. Further, the generated raster image is transmitted to the printing apparatus 10 via the network connection apparatus 50.

  FIG. 7 shows a schematic configuration of the image generation server 60. The image generation server 60 has a CPU 61 that comprehensively controls the operation of the image generation server 60. The CPU 61 includes a RAM 62, a hard disk device 63, and a network communication unit 64 through a system bus.

  The CPU 61 is based on the OS program and executes middleware, application programs, and the like. The hard disk device 63 is a large-capacity nonvolatile storage device that stores various programs (programs for generating raster images) and received data. Each function of the image generation server 60 is realized by the CPU 61 executing various processes according to these programs.

  The RAM 62 is used as a work memory that temporarily stores various data when the CPU 61 executes processing based on a program, an image memory that stores image data, and the like. A program for generating a raster image is loaded from the hard disk device 63 to the RAM 62 and then executed by the CPU 61.

  The network communication unit 64 performs a function of communicating data with the inter-network connection device 50 through the LAN 3. A request (request job) for parallel RIP processing is received through the network communication unit 64, and a raster image generated based on the request is also transmitted to the client system 7 through the network communication unit 64.

  Next, print data handled by the printing apparatus 10 will be described.

  The printed material printed by the printing apparatus 10 is divided into a non-variable printed material and a variable printed material. FIG. 8A shows an example of a non-variable printed material, and FIG. 8B shows an example of a variable printed material. FIG. (A) shows a printed matter of the same content that is printed in large quantities, such as a poster or a flyer, as a non-variable printed matter. FIG. 8B shows a printed material including variable elements as part of the contents, such as a direct mail in which a different address name is printed for each destination as a variable printed material.

  A typical data format suitable for non-variable printing is the PDF format, and a typical data format suitable for variable printing is the PPML format (PPML data and PDF data are ZIP archived). Format). FIG. 9 shows PPML data for instructing to print the variable printed material shown in FIG. 8B, and FIG. 10 shows an example of PDF data referred to by the PPML file of FIG.

  PPML data is data indicating the arrangement and arrangement of PDF data. When printing, a raster image printed on one page of recording paper (hereinafter referred to as a page raster image) is created by arranging and synthesizing PDF data after RIP processing in the arrangement and arrangement indicated by the PPML data. Generate. The specification of PPML data is defined by PODi (Digital Printing Initiative), and PPML is actually described in XML (Extensible Markup Language) format, but FIG. 9 shows this easily.

  There are two types of PDF data: reusable objects that are repeatedly used in a plurality of pages, and temporary objects that are used only for one page. As shown in FIG. 9, in the PPML data, a reusable object is usually declared at the top, followed by the layout description of each page. Each page consists of a temporary use object only, or a temporary use object and a reuse object. In the example of FIG. 9, object 1, object 2, and object 3 on page 1 are temporarily used objects, and object 4 is a reuse object. The same description continues on page 2 and thereafter, but the portion of the temporarily used object is variable for each page.

  FIG. 10 shows PDF data referenced from the PPML data of FIG. FIG. 10 shows the contents of each page when the PDF data is displayed in the Viewer. Page 1 is used as a reuse object, and pages 2 to 4 have contents corresponding to a postal code, an address, and a name used as a temporary use object. In page 5 and subsequent pages, temporary use objects whose contents have changed, that is, data on the contents of the zip code, address, and name corresponding to each person repeatedly appear.

  The printing apparatus 10 first RIPs the reuse object and caches a raster image (hereinafter referred to as a cache image) generated by the RIP process in the RAM 13. Thereafter, RIP is performed on the temporary use object of each page, and a raster image generated by the RIP processing (hereinafter referred to as a variable image) and a cache image are combined with the arrangement and arrangement indicated by the PPML data, thereby generating a page raster image. Is generated.

  Next, a functional configuration for processing for generating a page raster image from print data and a flow of processing will be described.

  FIG. 11 is a functional configuration diagram for performing processing for generating a page raster image from PPML data in the printing system 5 of the present invention. Here, the inter-network connection device 50 is omitted.

  The client system 7 includes a client terminal 40 and a printing device 10. The printing device 10 includes a hard disk device 14, a spooler thread 81, a reuse object image cache memory 82, a transmission thread 83, a PPML interpreter thread 84, A PS (Post Script) / PDF interpreter thread 85, an engine control thread 86, a reception / engine transfer thread 87, a frame memory 88, and the printer engine 20 are included.

  The spooler thread 81 receives a print job (print data) from the client terminal 40 and stores it in the hard disk device 14.

  The PPML interpreter thread 84 has a function of generating a page raster image by using PPML data of print data stored in the hard disk device 14. When necessary, a request job for requesting parallel RIP processing is transmitted to the cloud service system 6 via a transmission thread 83 described later. When generating a page raster image, the reusable object is RIPed and cached as a cache image. When a variable image is generated, it is combined with a cache image in a frame memory 88 described later.

  The PS / PDF interpreter thread 85 has a function of performing RIP processing on a PDF file included in a print job and generating a raster image (cache image or variable image).

  The frame memory 88 is used to temporarily store the generated variable image and synthesized page image. The reuse object image cache memory 82 is used when a RIP reuse object (cache image) is cached.

  The engine control thread 86 has a function of transferring a page raster image to the printer engine 20.

  The transmission thread 83 has a function of transmitting a request job for requesting parallel RIP processing to the cloud service system 6.

  The reception / engine transfer thread 87 has a function of receiving a compressed page raster image from the cloud service system 6, storing it in the frame memory 88, decompressing it, and notifying the engine control thread 86.

  The cloud service system 6 includes an image generation server 60. The image generation server 60 includes a hard disk device 63, a reception thread 91, a PPML interpreter thread 92, a frame memory 93, a PS / PDF interpreter thread 94, and a reuse object image cache. The memory 95 is configured.

  The reception thread 91 receives the request job from the transmission thread 83 and stores it in the hard disk device 63.

  The PPML interpreter thread 92 has a function of generating a page raster image in accordance with PPML data included in the request job stored in the hard disk device 63. Further, the generated page raster image is compressed and transmitted to the client system 7.

  The PS / PDF interpreter thread 94 has a function of RIPing a PDF file included in the request job and generating a raster image (cache image or variable image).

  The frame memory 93 is used to temporarily store the generated variable image and synthesized page image. The reuse object image cache memory 95 is used when a RIP reuse object (cache image) is cached.

  The cloud service system 6 may include a plurality of image generation servers 60 as shown in FIG. A request job distribution method in this case will be described.

  When there are a plurality of image generation servers 60, one image generation server 60 serves as a representative server to receive a request job, and based on the load status of each image generation server 60 including its own device, The image generation server 60 that performs RIP processing is determined, and the received request job is transferred to the determined image generation server 60.

  When the reception thread 91 of the image generation server 60 serving as a representative server receives a request job, the request job is related to a request job that is already being processed by any of the image generation servers 60. The image generation server 60 is transferred to the image generation server 60. Otherwise, the image generation server 60 having a small number of jobs being processed is selected and transmitted.

  The above is the method for distributing the request jobs among the plurality of image generation servers 60. However, in the following description, the description of the distribution process is not performed so that the description contents are not excessively complicated. (The description assumes a cloud service system 6 in which only a single image generation server 60 exists.)

  Next, a detailed processing flow performed when the printing system 5 of the present invention generates a page raster image will be described. 12, 13, and 14 show the flow of detailed processing performed when generating a page raster image in the printing system 5. 13 and 14 show the flow of processing performed by the client system 7 and the processing performed by the cloud service system 6. The flow of the latter processing is surrounded by a broken line, and the flow of the former processing is shown. Shown separately.

  First, the client system 7 receives the ZIP archived variable data (print data) and stores it in the hard disk device 14 (referred to as HDD in the figure) (step S101). This is executed by the spooler thread 81 (see FIG. 11).

  Hereinafter, the processing is executed with the PPML interpreter thread 84 as the center. In step S102, the ZIP file stored in the hard disk device 14 is decompressed to obtain PPML data and PDF data.

  In step S103, the PDF data indicated as the reuse object by the PPML data acquired in step S102 is RIP (a cache image is generated) and stored in the cache memory. Note that the PPML interpreter thread 84 is used in the process of generating the page raster image, and the PS / PDF interpreter thread 85 is used in the process of RIPing the PDF data, but the description thereof will be omitted below.

  Next, page raster images for 10 pages are generated and transferred to the printer engine 20 (step S104). Specifically, in the processing in step S104, first, the temporary use object of the processing target page is RIPed (a variable image is generated), and the cache image and the variable image related to the reuse object included in the page are combined. . Thereafter, the engine control thread 86 transfers the page raster image to the printer engine 20. This series of processing is repeated for 10 pages. The printer engine 20 performs printing based on the transferred page raster image.

  In step S104, the time required to generate page raster images for 10 pages is measured. Next, the PPML interpreter thread 84 calculates the generation speed (average generation speed) of the page raster image for one page from the actually measured value measured in step S104, and determines whether or not it is slower than the printing speed of the printer engine 20. Determination is made (step S105).

  The printing speed of the printer engine 20 is determined in advance depending on the paper size and the paper feeding direction (long / short direction of paper), and is compared with this speed value. If the average generation speed is equal to or higher than the printing speed of the printer engine 20 (step S105; Yes), it is determined whether or not the printing is finished (step S106). If the printing is finished (step S106; Yes), the processing is performed. Exit. If it is not the end of printing (step S106; No), the process returns to step S104 and continues.

  Here, the average generation speed of the page raster image obtained from the time required for generating the page raster image for 10 pages and the printing speed of the printer engine 20 are compared, particularly in the case of variable print data. This is because there are many cases where a page group having a large amount of data appears periodically and it is desirable to average the processing time.

  As described above, as long as the average generation speed exceeds the printing speed of the printer engine 20, the processing is completed in the client system 7.

  In step S105, when it is determined that the raster image supply speed is lower than the printing speed of the printer engine 20 (step S105; No), the cloud service system 6 performs the RIP process for a part of the print data. To start.

  First, in step S107 in FIG. 13, the PPML interpreter thread 84 extracts a portion (description etc.) related to the reuse object in the print data (PPML data, PDF data), performs ZIP archive, and transmits it to the cloud service system 6. To do.

  Next, processing distribution between the client system 7 and the cloud service system 6, that is, a processing amount (request amount) for requesting the cloud service system 6 to perform parallel RIP processing is determined (step S108). The requested amount determined here is an initial value. Requests for parallel RIP processing are repeatedly performed thereafter, and the request amount is increased or decreased each time depending on the degree of congestion (load status) of the image generation server 60. In the embodiment, the requested amount is determined for each page.

  The initial value of the requested amount is determined with the upper limit being the amount that the raster image generation by the image generation unit 15 is not in time for image formation by the printer engine 20. Basically, it is assumed that the image generation unit 15 continues to perform the RIP processing for the time, and the cloud service system 6 is substituted for the shortage (the time is not enough).

  Specifically, the PPML interpreter thread 84 determines the distribution amount of processing performed by the client system 7 and the cloud service system 6, and the distribution amount determines the initial value of the request amount. First, the productivity ratio of the printer controller with respect to the printing speed of the printer engine 20 is calculated from the time required for generating page raster images for 10 pages executed in step S104.

If the generation time of the page raster image for 10 pages is N (seconds), the printing speed of the printer engine 20 is S (PPM), and the productivity ratio to be obtained is R,
Formula “R = 60 × 10 ÷ N ÷ S”
R can be calculated by substituting specific numerical values for. Next, the processing distribution amount is determined based on the productivity ratio (R). If the subsequent parallel RIP processing request is repeated in units of 15 pages, and the distribution on the client system 7 side is C (page),
“C = 15 × R” (turned to an integer by rounding down)
Thus, the distribution on the cloud service system 6 side is obtained by “15-C”. For example, when the printing speed (S) is 60 PPM and the generation time (N) is 15 seconds, the productivity ratio R is 0.666..., The distribution C on the client system 7 side is 10 pages, and the cloud service system 6 The side distribution is 5 pages. In this way, the initial value of the requested amount of parallel RIP processing requested to the cloud service system 6 is determined.

  Even if the generation speed of the raster image is increased by the parallel RIP process, if the generation speed is less than the image forming speed of the printer engine 20, the time (X and ), The process is allocated so that the time (Y) estimated to be the process assigned to the cloud service system 6 becomes equal (X = Y).

  Next, the PPML interpreter thread 84 ZIPs the PPML data and PDF data used in the parallel RIP processing requested to the cloud service system 6 based on the request amount determined in step S108, and transfers the ZIP archive to the cloud service system 6 ( Step S109).

  Now, let us move on to the description of the flow of processing performed once in the cloud service system 6 (image generation server 60). First, after the cloud service system 6 is activated, the image generation server 60 first waits for a connection from the client system 7 (step S201).

  When connection is made in the operation of step S107 of the client system 7, the cloud service system 6 receives the ZIP archive and stores it in the hard disk device 63 (step S202). This is an operation performed by the reception thread 91.

  Next, the PPML interpreter thread 92 decompresses the ZIP archive file stored in the hard disk device 63, and extracts PPML data and PDF data (step S203). The extracted PPML data and PDF data include only data related to the reuse object.

  Next, the PPML interpreter thread 92 uses the function of the PS / PDF interpreter thread 94 to generate a cache image from the extracted PPML data and PDF data, and stores the generated cache image in the reuse object image cache memory 95 ( Step S204).

  Next, the ZIP archive transmitted from the client system 7 in step S109 of the client system 7 is received and stored in the hard disk device 63 (step S205). This is an operation performed by the reception thread 91.

  Next, in step S206 in FIG. 14, page raster image generation processing for the portion allocated to the cloud service system 6 is performed. Specifically, first, in the PPML interpreter thread 92, the ZIP archive file stored in the hard disk device 63 is decompressed in step S205. From the PPML data and PDF data obtained by the decompression, the temporary use object of the processing target page is RIP to generate a variable image. A cache image related to the reuse object included in the page is read from the reuse object image cache memory 95, and the variable image and the cache image are combined in the frame memory 93 to generate a page raster image.

  Thereafter, the generated page raster image is compressed and then transmitted (returned) to the client system 7 via the WAN 4 (step S207). Note that the steps S206 and S207 are repeated for the number of pages allocated to the cloud service system 6.

  Returning to the description of the operation of the client system 7. In step S110 of FIG. 14, in parallel with the operation of step S206 of the cloud service system 6, a page raster image for the page allocated to the client system 7 is generated and transferred to the printer engine 20. Specifically, the same processing as that performed in step S104 is repeated for the number of allocated pages.

  The reception / engine transfer thread 87 receives the page raster image (compressed state) transmitted / returned from the cloud service system 6 and stores it in the frame memory 88 (step S111).

  Next, the page raster image (compressed state) stored in the frame memory 88 is expanded, and the page raster image after the expansion processing is sent to the printer engine 20 by using the function of the engine control thread 86. Transfer is performed (step S112). Note that the steps S111 and S112 are also repeated for the number of pages allocated to the cloud service system 6.

  Next, the PPML interpreter thread 84 determines whether or not the processing of all data has been completed (whether or not printing has been completed) (step S113), and if completed (step S113; Yes), terminates the processing. To do.

  If all data has not been completed (step S113; No), the distribution amount of processing performed by the client system 7 and the cloud service system 6 is readjusted when processing the remaining print data.

  When adjusting the request amount, as in the case of step S108, X is assumed to be X ≧ Y (the time estimated to be assigned to the image generation unit 15 is X, and the process assigned to the cloud service system 6 is performed. The amount of processing allocated to each of them is adjusted. Even if the generation speed of the raster image is increased by the parallel RIP process, if the generation speed is less than the image formation speed of the printer engine 20, the requested amount is adjusted so that X = Y.

  First, the PPML interpreter thread 84 compares the time required for the RIP processing allocated to the client system 7 and the cloud service system 6 respectively.

  If the time required for the RIP process assigned to the client system 7 and the time required for the RIP process assigned to the cloud service system 6 are the same (step S114; Yes), the process proceeds to step S118.

  If the time required for the RIP process assigned to the client system 7 is not the same as the time required for the RIP process assigned to the cloud service system 6 (step S114; No), the time required for the RIP process assigned to the client system 7 However, if it is more than the time required for the RIP process assigned to the cloud service system 6 (step S115; No), the request amount of the parallel RIP process in the next request job is added (step S117), that is, the cloud service The processing amount allocated to the system 6 is added, and the process proceeds to step S118.

  If the time required for the RIP process assigned to the client system 7 is less than the time required for the RIP process assigned to the cloud service system 6 (step S115; Yes), the request amount of the parallel RIP process in the next request job is set. Subtract (Step S116) and go to Step S118.

  Steps S115 to S117 are basically positioned to adjust the requested amount of parallel RIP processing in accordance with the processing capability (load situation) of the cloud service system 6 and the like. The image generation server 60 determines the processing capability of the image generation server 60 from the time required to digest the requested amount requested in step S109 because the processing capability changes depending on the load situation (such as congestion). The amount of requests for the next request is adjusted.

  In step S118, the PPML interpreter thread 84 determines whether there is a margin in the processing capacity of the printer controller (client system 7). If there is a margin (step S118; Yes), the requested amount of parallel processing in the next request job is subtracted (step S119), and the process returns to step S109 and continues.

  Step S119 is a re-correction process for the margin of the processing capacity of the printer controller (client system 7) caused by the correction process (addition or subtraction) of the request amount of the parallel RIP process in the next request job performed in steps S114 to S117. Or, the position of the correction process for the capacity margin of the printer controller caused by the change in the weight of data in the print job. It is desirable that the RIP processing for the time when the raster image generation by the image generation unit 15 of the client system 7 is in time for the image formation of the printer engine 20 is preferably performed by the image generation unit 15. Only the processing amount is increased, and the request amount assigned to the cloud service system 6 is subtracted.

  Specifically, a value obtained by multiplying the average processing time for one page in step S110 by the number of pages assigned to the client system 7 after the correction (addition or subtraction) in step S114 to step S117 is obtained in step S108. It is determined whether or not the time taken to generate the page raster image for the acquired 10 pages (the page allocated when the initial value is determined) has not been reached. Is subtracted so that the number of pages allocated to the cloud service system 6 is subtracted, and the subtraction value is added to the number of pages allocated to the client system 7.

  If the printer controller has no margin in step S118 (step S118; No), or after re-correction of cloud allocation in step S119, the process returns to step S109 and continues.

  FIG. 15 shows the flow of parallel RIP processing in a time chart format when the printing system 5 performs parallel RIP processing. The time chart shown in FIG. 15 corresponds to step S107 to step S119 and step S202 to step S207 in the processing flow of FIGS.

  A, B, and C in FIG. 15 are parts included in the client system 7, and A = PPML interpreter thread 84 (see FIG. 11), B = send thread 83 (see FIG. 11), and C = receive / engine transfer. This represents the thread 87 (see FIG. 11). FIG. 15D is a part included in the cloud service system 6 and represents D = PPML interpreter thread 92. Actually, in the cloud service system 6, the operation of the reception thread 91 is interposed, but in this figure, this operation is omitted, and the PPML interpreter thread 92 is shown as having a reception function. Note that the page numbers shown in FIG. 15 are relative numbers obtained by assigning numbers in order from 1 to the target pages processed after it is determined in step S105 (see FIG. 12) that parallel RIP processing is necessary. Page number.

  Step S301 in FIG. 15 corresponds to the processing operation corresponding to the processing in step S110 executed first after it is determined in step S105 in FIG. 12 that parallel RIP processing using the cloud service system 6 is necessary. It is. In FIG. 15, the number of pages allocated to the client system 7 is 10 pages, and step S <b> 301 shows a processing operation for generating page raster images of 1 to 10 pages and transferring them to the printer engine 20.

  Since parallel processing has not yet been performed at the start of step S301, generation and transfer of a page raster image at a printing speed higher than that of the printer engine 20 has not been performed. At the same time as starting Step S301, the PPML interpreter thread 84 uses the transmission thread 83 to transfer the ZIP archive including the print data corresponding to the pages 11 to 15 (Step S302).

  The PPML interpreter thread 92 of the cloud service system 6 decompresses the ZIP archive received from the transmission thread 83, generates a page raster image of pages 11 to 15, compresses the generated page raster image, and receives / Return (send) to the engine transfer thread 87 (step S303).

  The reception / engine transfer thread 87 stores the received compressed image data in the frame memory 88 (see FIG. 11), and transfers it to the printer engine 20 while expanding (step S304). Here, it is expected that the transfer to the printer engine 20 is started immediately after the end of step S301, and the page raster image is transferred so as not to be delayed by the printing speed of the printer engine 20. If this is not the case, the number of pages allocated to the cloud service system 6 is too large, and the number of pages allocated to the cloud service system 6 is subtracted and corrected for the next request for parallel RIP processing.

  The PPML interpreter thread 84 of the client system 7 transfers the ZIP archive corresponding to the pages 26 to 30 to the cloud service system 6 immediately after the generation of the page raster image for 10 pages and the transfer to the printer engine 20 is completed (step). S305)

  Thereafter, page raster images corresponding to pages 16 to 25 are generated and compressed, and stored in the frame memory 88 (step S306).

  Next, the PPML interpreter thread 84 confirms that the transfer of the page raster image returned by the cloud service system 6 in step S304 to the printer engine 20 is completed, and the compressed page raster images of the pages 16 to 25 are compressed. Decompression and transfer to the printer engine 20 are performed (step S307).

  The processing here is started immediately after the end of step S304, and it is expected that the page raster image will be supplied (transferred) at a speed higher than the printing speed of the printer engine 20, but as expected. If this is not the case, the number of pages allocated to the cloud service system 6 will be too small. Therefore, the number of pages allocated to the cloud service system 6 is added and corrected for the parallel RIP processing of the next cycle. Further, at this timing, subtraction correction of the allocated page number corresponding to steps S118 and 119 in FIG. 14 is further performed.

The above is one cycle of basic parallel RIP processing, and step S308 in the figure performs the same processing as step S303 on the ZIP archive corresponding to pages 26 to 30 transmitted in step S305. In step S309, processing similar to that in step S304 is performed on the page raster images of pages 26 to 30 generated in step S308.

  As described above, in the printing system 5 of the present invention, it is possible to make a request for parallel RIP processing and adjust the request amount. As a result, even if the data of the page raster image cannot be generated / supplied at a speed equivalent to or faster than the printing speed of the printer engine 20 by the capability of the printer controller of the client system 7, the page raster image can be generated by parallel RIP processing. The generation / supply speed can be increased, and the raster image can be generated / supplied at the same speed as the printer engine 20.

  Basically, the image generation unit 15 performs RIP processing in time for the raster image generation by the image generation unit 15 to be in time for image formation by the printer engine 20, and the cloud service system 6 performs the missing amount (the amount in time). The requested amount is determined in such a way as to act on behalf of. Accordingly, it is possible to suppress the occurrence of a printer engine speed reduction as much as possible while using the hardware resources of the printing apparatus 10 as much as possible.

  In addition, the parallel RIP processing can be performed most efficiently in the entire printing system 5 by adjusting the request amount of the parallel RIP processing in accordance with the processing capability (load status or the like) of the cloud service system 6.

  The embodiment of the present invention has been described with reference to the drawings. However, the specific configuration is not limited to that shown in the embodiment, and there are changes and additions within the scope of the present invention. Are also included in the present invention.

  In the present embodiment of the present invention, the software function configuration corresponding to PPML data and the flow of processing have been described. However, as a mode for carrying out the present invention, a software function configuration corresponding to another PDL may be adopted. Absent. For example, PDF / PostScript, XPS, PCL / XL format data, etc., unlike PPML data, the PDL data analysis and raster image generation functions are completed with a single interpreter function. A difference between the case where such a PDL interpreter function is adopted and the case where a function corresponding to PPML data is adopted will be described.

  First, in the thread configuration of FIG. 11, the PPML interpreter thread 84 and the PS / PDF interpreter thread 85 in the client system 7 are aggregated into a single interpreter thread, and similarly, the PPML interpreter thread 92 and PS / in the cloud service system 6 The PDF interpreter thread 94 will also be aggregated into a single interpreter thread.

  In addition, in the processing flow of FIGS. 12 to 14, steps S <b> 101 and S <b> 102 in the client system 7 are processes for storing received data in the hard disk device 14 and reacquiring the stored data from the hard disk device 14. . Further, Step S103 and Step S107 in the client system 7, and Step S202, Step S203, and Step S204 in the cloud service system 6 are unique processing steps when processing PPML data, and are unnecessary. Furthermore, step S109 and step S205 are processing for extracting and transmitting the allocation to the cloud service system 6 from the PDL to be processed, and for receiving the cloud service system 6. The page raster image handling processing operation and various determination operation portions other than the above steps are unchanged even in the case of PDL other than PPML data.

  The print data is not limited to the PDL (page description language) format.

  In the embodiment of the present invention, the processing capacity (congestion status) of the cloud service system 6 depends on the amount of requests for parallel RIP processing and the time from when a request job is sent to the cloud service system 6 until the reply is received. The next request amount is adjusted, but information indicating the congestion state (load status) is directly acquired from the cloud service system 6 and the next request amount is adjusted based on the information. Good.

  In the parallel RIP process, the method for determining the processing amount (request amount) requested to the cloud service system 6 is not limited to the method used in the embodiment. For example, it may be determined so as not to correspond to the load situation. It may be a fixed value. Further, the increase / decrease in the request amount may not be in units of pages.

3 ... LAN
4 ... WAN
DESCRIPTION OF SYMBOLS 5 ... Printing system 6 ... Cloud service system 7 (7A, 7B, 7C) ... Client system 10 (10A, 10B) ... Printing apparatus 11 ... CPU
12 ... Flash memory 13 ... RAM
DESCRIPTION OF SYMBOLS 14 ... Hard disk apparatus 15 ... Image generation part 16 ... Network I / F part 17 ... Video I / F
20 ... Printer engine 40 ... Client terminal 41 ... CPU
42 ... RAM
43 ... Hard disk device 44 ... Network communication unit 45 ... Input I / F
46 ... Keyboard 47 ... Pointing device 48 ... Output I / F
49 ... Monitor 50 ... Network connection device 51 ... CPU
52 ... Flash memory 53 ... RAM
54 ... 1st network I / F part 55 ... 2nd network I / F part 60 (60A, 60B) ... Image generation server 61 ... CPU
62 ... RAM
DESCRIPTION OF SYMBOLS 63 ... Hard disk apparatus 64 ... Network communication part 81 ... Spooler thread 82 ... Reuse object image cache memory 83 ... Transmission thread 84 ... PPML interpreter thread 85 ... PS / PDF interpreter thread 86 ... Engine control thread 87 ... Reception / engine transfer thread 88 ... Frame memory 91 ... Receive thread 92 ... PPML interpreter thread 93 ... Frame memory 94 ... PS / PDF interpreter thread 95 ... Reuse object image cache memory

Claims (10)

A raster image generation unit that performs RIP processing for generating a raster image based on print data;
A printer engine that forms an image on paper based on the raster image generated by the raster image generation unit;
If it is determined that the raster image generation speed by the raster image generation unit is lower than the image formation speed of the printer engine, a part of the RIP processing for the print data is transferred to a predetermined image generation server on the network. A control unit that causes the printer engine to perform image formation based on the raster image generated by the raster image generation unit and the raster image received as a result of the substitution from the image generation server;
I have a,
The raster image generating unit expands a reuse object when generating a raster image of each page based on the print data, and then uses the image of the expanded reuse object based on the print data. Generate raster images for each page,
The control unit measures the time taken for the raster image generation unit to generate raster images for N (N is an integer equal to or greater than 1) pages using the expanded image of the reused object, and the measurement A printing apparatus that calculates a development speed per page based on a result . The printing apparatus according to claim 1, wherein the control unit determines a processing amount to be substituted for the image generation server according to a load state of the image generation server. The control unit determines the load status of the image generation server based on a time period from requesting the image generation server to perform the proxy of the RIP processing until receiving a raster image of the proxy result. The printing apparatus according to claim 2. The control unit determines an amount of processing to be substituted for the image generation server, with an upper limit of RIP processing for the raster image generation by the raster image generation unit in time for image formation of the printer engine. The printing apparatus according to any one of claims 1 to 3.   A raster image generation unit that performs RIP processing for generating a raster image based on print data;
  A printer engine that forms an image on paper based on the raster image generated by the raster image generation unit;
  If it is determined that the raster image generation speed by the raster image generation unit is lower than the image formation speed of the printer engine, a part of the RIP processing for the print data is transferred to a predetermined image generation server on the network. A control unit that causes the printer engine to perform image formation based on the raster image generated by the raster image generation unit and the raster image received as a result of the substitution from the image generation server;
  Have
  The control unit determines a load state of the image generation server based on a time period from requesting the image generation server to perform the RIP processing on behalf to receiving a raster image of the substitution result, and the image generation server The processing amount to be substituted for the image generation server is determined according to the load status of
  A printing apparatus characterized by that.   A raster image generation unit that performs RIP processing for generating a raster image based on print data;
  A printer engine that forms an image on paper based on the raster image generated by the raster image generation unit;
  If it is determined that the raster image generation speed by the raster image generation unit is lower than the image formation speed of the printer engine, a part of the RIP processing for the print data is transferred to a predetermined image generation server on the network. A control unit that causes the printer engine to perform image formation based on the raster image generated by the raster image generation unit and the raster image received as a result of the substitution from the image generation server;
  Have
  The control unit determines a processing amount to be substituted for the image generation server, with an upper limit of RIP processing for the raster image generation by the raster image generation unit in time for image formation of the printer engine.
  A printing apparatus characterized by that. The control unit determines a processing amount to be substituted for the image generation server so that the processing time in the image generation server is equal to the processing time in the raster image generation unit within a range not exceeding the upper limit. The printing apparatus according to claim 4 or 6 . Wherein the control unit, the printing apparatus according to the processing amount to be intercepted on the image generation server, to any one of claims 1 to 7, characterized in that the increase or decrease in page units. The printing apparatus according to any one of claims 1 to 8 , wherein the print data is print data described in a page description language. A printing apparatus according to any one of claims 1 to 9 ,
An image generation server that performs RIP processing requested by the printing apparatus and transmits a raster image as a result to the printing apparatus;
A printing system characterized by comprising:

Images