JP2010277269A - Information processor, image forming device and image forming system including them - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To print a document of a prescribed format in a shorter time without converting the document into a PDL language by an information processor side printer driver. <P>SOLUTION: When using a single image forming device by a plurality of PCs, an access table is created according to the document of a print target in each of the plurality of PCs. The image forming device receives the access table (S20), acquires an offset address belonging to a page number from the access table about each page number (S22, S25), transmits it to the PC (S23, S26), and acquires a content and a resource corresponding to the offset address from the PC (S24, S27). The image forming device 20 can receive the access table 45 and a PDF document and can acquire the content and the resource inside it even if offset addresses corresponding to a plurality of pages have been transmitted collectively to acquire the corresponding contents and resources collectively. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an information processing apparatus that processes data of an electronic document in a predetermined format such as PDF, an image forming apparatus that uses the processing result, and an image forming system including these.

In the following Patent Document 1, when printing the contents of a PDF (Portable Document Format) file, a cross reference table and a trailer of the PDF file are transmitted from a host computer to an image forming apparatus to a PC (personal computer). In the image forming apparatus, first, the offset of the root (catalog object) (the number of bytes from the beginning of the PDF file to the beginning of the root) is transmitted to the PC, and the PC extends from this offset to the character string “endobj” indicating the object delimiter. Is transmitted to the image forming apparatus. In response to this, the image forming apparatus obtains an offset from the cross reference table based on the Pages object number included in this object, and transmits this to the PC. In response to this, the PC similarly transmits a Pages object to the image forming apparatus. In response to this, the image forming apparatus acquires the offset from the cross reference table based on the Page object number included in this object, and transmits it to the PC. Thereafter, the same two-party communication is repeated, and the image forming apparatus receives the contents and resource objects of each page from the PC, develops a bitmap for each page, and performs printing.
JP 2004-171204 A

  According to this method, it is not necessary to convert the PDF document into the PDL language by the printer driver on the PC side.

  However, since communication between the PC and the image forming apparatus is frequently performed while referring to the cross-reference table and tracing the complicated tree to acquire the contents and resources of each page, the time required for communication is reduced. It becomes longer and the printing process is delayed.

  In view of such problems, an object of the present invention is to provide an information processing apparatus capable of performing printing in a shorter time without converting a document in a predetermined format into the PDL language by an information processing apparatus side printer driver. It is an object to provide a forming apparatus and an image forming system including these.

In the first aspect of the present invention, the content of each page is described by an indirect object with an identifier, the content object with an identifier is described in each indirect object, and the identifiers of the indirect object and the content object are in the cross-reference table. In an information processing apparatus that transmits data of an electronic document that is associated with an offset and that describes the contents of the corresponding indirect object or content object in a range from the offset to the object end identifier, to the image forming apparatus.
An access table creating means for creating an access table having a set of a page number and an offset corresponding to each content object included in the page of the page number for each page;
Transmitting means for transmitting the access table to the image forming apparatus and transmitting a content object corresponding to the offset to the image forming apparatus in response to one or more offsets received from the image forming apparatus;

According to a first aspect of the image forming apparatus of the present invention, the image forming apparatus includes a communication unit, a printing unit, and a control unit.
An access table having a set of a page number and an offset corresponding to each content object included in the page identified by the page number is received from the outside via the communication means,
For each page number, an offset belonging to the page number is acquired from the access table and transmitted to the outside via the communication means.
A content object corresponding to the offset is received from the outside via the communication means,
An image is formed on a sheet by developing the content object into a bitmap and supplying it to the printing unit.

According to a second aspect of the image forming apparatus of the present invention, the image forming apparatus includes a print data input unit, a printing unit, and a control unit.
The print data input means includes
The contents of each page are described by an indirect object with an identifier, the content object with an identifier is described in each indirect object, and the identifiers of the indirect object and the content object are associated with the offset in the cross reference table. An electronic document in which the contents of the corresponding indirect object or content object are described in the range from the object end identifier to
An access table having a set of a page number and an offset corresponding to each content object included in the page of the page number for each page;
From the outside,
The control means acquires, for each page number, an offset belonging to the page number from the access table, acquires a content object corresponding to the offset from the electronic document, expands the content object into a bitmap, and Forming an image on paper by supplying it to the printing section,
Image forming apparatus

  According to the configuration of the first aspect of the information processing apparatus, when one image forming apparatus is used by a plurality of information processing apparatuses, an access table is provided for each of the plurality of information processing apparatuses according to a document to be printed. Therefore, it is possible to efficiently perform distributed processing, there is no need to create an access table in the image forming apparatus, and by using the access table, the information processing apparatus side printer driver can convert the document into the PDL language. Without conversion, since the number of requests / responses between the information processing apparatus and the image forming apparatus is reduced, it is possible to perform printing in a shorter time.

  According to the configuration of the first aspect of the image forming apparatus, the control unit obtains an offset belonging to the page number from the access table for each page number, transmits the offset to the outside via the communication unit, and sets the offset. Since the corresponding content object is received from the outside via the communication means, the number of requests / responses between the information processing apparatus and the image forming apparatus without converting the document into the PDL language by the information processing apparatus side printer driver As a result, there is an effect that printing can be performed in a shorter time.

  According to the configuration of the second aspect of the image forming apparatus, an access table and a document are acquired via a communication unit or an external memory, and for each page number, an offset belonging to the page number is acquired from the access table, Since the content object corresponding to the offset is acquired from the electronic document, the access table and the document need only be acquired once from the outside without converting the document into the PDL language by the information processing apparatus side printer driver. As a result, it is possible to perform printing in a shorter time.

  Other objects, configurations and effects of the present invention will become apparent from the following description.

  FIG. 5 is a schematic configuration diagram of the image forming system according to Embodiment 1 of the present invention.

  In this system, the PC 10A, the PC 10B, and the image forming apparatus 20 are coupled to the LAN 30, and printing is performed by supplying print data from the PC 10A or the PC 10B to the image forming apparatus 20. This print data is data related to the PDF document.

  FIG. 6 is a schematic block diagram showing the hardware configuration of the PC 10A.

  In this PC 10 </ b> A, the CPU 11 is coupled to the EEPROM 13, DRAM 14, HDD 15, manual operation input device 16, display device 17, network interface 18, and USB port 19 via the interface 12. In FIG. 6, a plurality of types of interfaces are represented by one block 12 for simplification. The PC 10B is configured similarly to the PC 10A.

  The EEPROM 13 stores a BIOS, and the HDD 15 stores a virtual storage OS, various drivers, and applications. The DRAM 14 is used as a main storage device. The network interface 18 is coupled to the LAN 30, and the USB memory 31 is inserted into the USB port 19.

  FIG. 7 is a schematic block diagram illustrating a hardware configuration of the image forming apparatus 20.

  In the image forming apparatus 20, a CPU 21 is coupled to an EEPROM 23, a DRAM 24, an operation panel 26, a printing unit 27, a network interface 28, and a USB port 29 via an interface 22. In FIG. 7, for simplification, a plurality of types of interfaces are represented by one block 22.

  The EEPROM 23 stores an OS (Operating System), various drivers, and applications. The DRAM 24 is used as a work area. The operation panel 26 includes keys and a display panel. The printing unit 27 includes a print engine, a paper feeding unit, a conveyance unit, and a paper discharge unit. The bitmap data generated in the DRAM 24 is supplied to form an electrostatic latent image on the photosensitive drum based on the data. Then, this image is developed with toner, and the toner image is transferred and fixed on a sheet, and discharged. The network interface 28 is coupled to the LAN 30, and the USB memory 31 is inserted into the USB port 29.

  FIG. 3 shows a specific example of the PDF document 40.

  The PDF document 40 includes a header 41, a body 42, a cross reference table 43, and a trailer 44.

  In the header 41, the PDF specification version is described as a comment starting with “%”.

  The body 42 includes indirect objects 10obj to 70obj constituting the document. Here, the indirect object is an object that can be accessed by name or number. The indirect object is, for example, from “10 obj” to a delimiter “endobj”. The first number “1” and the next number “0” of the ID “10” included in this “1 0 obj” are an object number and a generation number, respectively, and “R” indicates an indirect reference. ing.

  The cross reference table 43 starts with xref and represents offsets in the PDF document 40 of all indirect objects in the PDF document 40 (hereinafter simply referred to as “offset”). The first number “0” and the next number “9” in the first data row “09” are the first object number and the number of entries, respectively. It is shown that they are included in order in the reference table 43 (only one entry is not shown in FIG. 3). F in the entry “0000000000 65535 f” of the object number 0 indicates that the object is not used and can be ignored. “0000000019” of the entry “0000000019 00000 n” of the object number 1 is the offset of the indirect object of the object number 1, “00000” following this is the generation number of this object, and “n” following this is the object number. Indicates that it will be used. The same applies to object number 2 and later.

  “Size 9” and “Root 1 0 R” in the first line “trailer << / Size 9 / Root 1 0 R >>” of the trailer 44 respectively have 9 entries in the cross-reference table 43 and This indicates that the indirect reference to the root (catalog object) is 10R (ID is 10).

The next “startxref” and the next “10100” indicate that the offset of the cross-reference table 43 is “10100”.

  Now, the application stored in the HDD 15 communicates between the program for generating the access table 45 as shown in FIG. 2 based on the PDF document and the image forming apparatus 20 to send print data to the image forming apparatus 20. And a program to transmit.

  FIG. 1 is a schematic flowchart showing processing by the former program. In the following, the step identification codes in the figure are shown in parentheses.

  (S0) The offset and the route number of the cross reference table 43 are acquired from the trailer 44 included in the PDF document 40. In the case of FIG. 3, the offset of the cross reference table 43 is “10100”, and the route number is “1”.

  (S1) Based on this offset, the cross-reference table 43 is acquired.

  (S2) The offset of the route number is acquired from the cross reference table 43 acquired in step S1. In the case of FIG. 3, this offset is “19”.

  (S3) The indirect reference “20R” of the Pages object included in the route 10obj starting from this offset is acquired. The offset of the object number “2” is acquired from the cross reference table 43, and the count value included in the Pages object 20obj is entered in the total number of pages in the access table 45 shown in FIG. In the case of FIG. 3, since “/ Count 1”, that is, the count value is “1”, “1” is entered in the total number of pages.

  (S5) The initial value 1 is substituted for i.

  (S6) The i-th element (indirect reference) of the Kids array included in the Pages object 20obj is acquired. The value of i is entered as “page number” in the access table 45. The i-th indirect reference offset is acquired from the cross-reference table 43, and the indirect object is acquired. In the case of FIG. 3, the number of elements in the Kids array is 1, the indirect reference is “30R”, the offset is “167”, and the indirect object 30obj is acquired.

  (S7) The initial value 1 is substituted for j.

  (S8) The j-th row (logical row) is read from this indirect object.

  (S9) If this one line is an indirect reference of content (Contents object), the process proceeds to step S10, and if not, the process proceeds to step S13. The content includes a drawing command.

  (S10) Based on the object number of the indirect reference, the offset is obtained from the cross reference table 43 in the same manner as described above. In the case of FIG. 3, if this one line is “/ Contents 40R”, an offset “311” is acquired.

  (S11) The obtained offset is entered in the access table 45. At this time, depending on whether the offset is a content offset or a resource offset, it is separately written in the access table 45.

  (S12) The “total number” next to “page number” is incremented by one. The initial value of “total number” is 0.

(S13) If this one line is an indirect reference to a resource (Resources object), the process proceeds to step S14; otherwise, the process proceeds to step S15. A resource is an object such as image data or a printer font, and is referred to by name. In FIG. 3, the object referred to by “/ PDF / Text” of 50obj is not shown.
(S14) Based on the indirect reference object number, the offset is obtained from the cross reference table 43 in the same manner as described above. In the case of FIG. 3, if this one line is “/ Resources << / ProcSet 50R / Font << / F1 60R >>>>”, the offsets “414” and “447” of the object numbers 5 and 6 are acquired. . Next, the process proceeds to step S10.

  (S15) If the line is not endobj, j is incremented by 1, and the process returns to step S8.

  (S16) If the value of i is equal to the total number of pages, the process proceeds to step S17. Otherwise, i is incremented by 1, and the process returns to step S6.

  (S17) The access table 45 created in this way is transmitted to the image forming apparatus 20.

  In the access table 45, for example, the total number of pages, page number, total number, and offset are all 4 bytes. For each page i of the access table 45, the last offset of the content is known from the total number pi of the content, the last offset of the resource is known from the total number of resources qi, and how far the end of the access table 45 is from these total number and the total number of pages n. I understand. Note that the offset values in FIG. 2 correspond to those in FIG.

  FIG. 4 is a flowchart showing processing by the image forming apparatus 20.

  (S20) The access table 45 is received.

  (S21) The initial value 1 is substituted into the page number i.

  (S22) Each offset of the content with the page number i is acquired from the access table 45.

  (S23) The acquired offset is transmitted to the PC 10A to request the object.

  In response to this, the PC 10A acquires an indirect object from the offset of the PDF document 40 to endobj indicating the delimiter of the object, and transmits it to the image forming apparatus 20.

  (S24) The image forming apparatus 20 receives the indirect object as content.

  (S25) Each offset of the resource of page number i is acquired from the access table 45.

  (S26) The obtained offset is transmitted to the PC 10A to request the object.

  In response to this, the PC 10A acquires an indirect object from the offset of the PDF document 40 to endobj indicating the delimiter of the object, and transmits it to the image forming apparatus 20.

  (S27) The image forming apparatus 20 receives this indirect object as a resource.

  (S28) Based on the contents and resources acquired in steps S24 and S27, respectively, the image is drawn on the memory, that is, the drawing command is developed into a bitmap, and the data is supplied to the print engine for printing.

  (S29) If i is equal to the total number of pages n, the printing process is terminated; otherwise, i is incremented by 1, and the process returns to step S22.

  According to the first embodiment, when one image forming apparatus 20 is used on a plurality of PCs, the access table 45 is created according to the document to be printed on each of the plurality of PCs. It is possible to perform distributed processing, and it is not necessary to create the access table 45 in the image forming apparatus, and by using the access table 45, the PC-side printer driver does not convert the document into the PDL language. Since the number of requests / responses between the image forming apparatus and the image forming apparatus is reduced, it is possible to perform printing in a shorter time.

  In the first embodiment, the case where the image forming apparatus 20 performs printing by acquiring print data in units of pages from the PC 10A has been described. However, depending on the buffer size on the image forming apparatus 20 side, print data for a plurality of pages may be simultaneously displayed. It is also possible to repeat the process of receiving, developing the bitmap, and printing for each page.

  FIG. 8 is a schematic flowchart showing such processing as a second embodiment.

  (S20) The access table 45 and the cross reference table 43 are received from the PC 10A.

  (S30) The size of the reception buffer secured in the DRAM 24 of the image forming apparatus 20 is acquired.

  (S31) The initial value 1 is substituted for i.

  (S32) About the i-th page, the size of the indirect object corresponding to each offset is calculated | required from each offset of the content and resource contained in this page, and the cross reference table 43, and those total size is calculated | required. If this total size is smaller than the buffer size acquired in step S30, i is incremented by 1, and similarly, it is determined how many pages of print data can be stored in the reception buffer. At this time, if the total size is larger than the buffer size acquired in step S30, i is decremented by one.

  (S33) The offsets for the determined number of pages are acquired from the access table 45 and transmitted to the PC 10A.

  (S34) All objects corresponding to the transmitted offset are received.

  (S35) For each page, an image is drawn on the memory based on the received content and resource object, that is, a drawing command is developed into a bitmap, and the data is supplied to the print engine for printing.

  (S36) If i is equal to the total number of pages n, the printing process is terminated; otherwise, i is incremented by 1 and the process returns to step S32.

  According to the second embodiment, since all the objects corresponding to the offsets for a plurality of pages can be received at one time, there is an effect that printing can be performed in a shorter time than the first embodiment.

  In each of the above embodiments, the case where the print data is acquired via the communication interface has been described. However, it is also possible to read the print data from the USB memory 31 and perform the same processing, which is shown as a third embodiment.

  In this case, on the PC 10A side, the access table 45 is created by the processing of FIG. 1, and the access table 45 and the PDF document 40 corresponding to the access table 45 are stored in the USB memory 31 as print data. Attached to the USB port 29 of the forming apparatus 20.

  FIG. 9 is a flowchart illustrating a process for printing by reading print data from the USB memory 31.

  (S40) The access table 45 and the PDF document 40 are read from the USB memory 31.

  (S41) The initial value 1 is substituted for i.

  (S42) The contents and resource offset of the i-th page are acquired from the access table 45.

  (S43) A corresponding indirect object (content and resource) is acquired from the PDF document 40 based on each of these offsets.

  (S44) Based on the acquired contents and resources, an image is drawn on the memory for each page, that is, the drawing command is developed into a bitmap, and the data is supplied to the print engine for printing.

  (S45) If i is equal to the total number of pages n, the printing process is terminated; otherwise, i is incremented by 1, and the process returns to step S42.

  According to the third embodiment, the access table 45 and the PDF document 40 are acquired via the USB memory 31, and for each page number, an offset belonging to the page number is acquired from the access table 45, and corresponding to the offset. Since the contents and resources are acquired from the PDF document 40, the access table 45 and the PDF document 40 may be acquired once from the outside without converting the document into the PDL language by the PC side printer driver. Thus, it is possible to perform printing in a shorter time.

  Although the preferred embodiment of the present invention has been described, the present invention includes various other modifications, and realizes other combinations of the components described in the above-described embodiments and the functions of the components. Other configurations using other configurations, and other configurations that would be conceived by those skilled in the art from these configurations or functions, are also included in the present invention.

 For example, in the third embodiment, a communication unit is used instead of the USB memory 31 as an input unit, the PDF document 40 and the access table 45 are acquired from the PC 10A via the LAN 30, and printing is performed in the same manner as in FIG. There may be.

It is a schematic flowchart of the access table preparation process and its table transmission in PC in Example 1 of this invention. It is an access table explanatory drawing. It is a specific example explanatory drawing of a PDF document. 3 is a schematic flowchart illustrating printing processing by the image forming apparatus. 1 is a schematic configuration diagram of an image forming system according to Embodiment 1 of the present invention. It is a schematic block diagram which shows the hardware constitutions of PC10A in FIG. FIG. 6 is a schematic block diagram illustrating a hardware configuration of the image forming apparatus 20 in FIG. 5. It is a schematic flowchart which shows the printing process which concerns on Example 2 of this invention. 10 is a schematic flowchart illustrating print processing using a USB memory according to a third embodiment of the present invention.

10A, 10B, 10 PC
20 Image forming apparatus 30 LAN
11, 21 CPU
12, 22 Interface 13, 23 EEPROM
14, 24 DRAM
15 HDD
16 Manual operation input device 17 Display device 18, 28 Network interface 19, 29 USB port 27 Printing unit 26 Operation panel 31 USB memory 40 PDF document 41 Header 42 Body 43 Cross-reference table 44 Trailer 45 Access table

Claims (5)

The contents of each page are described by an indirect object with an identifier, the content object with an identifier is described in each indirect object, and the identifiers of the indirect object and the content object are associated with the offset address in the cross-reference table, In an information processing apparatus that transmits data of an electronic document in which contents of a corresponding indirect object or content object are described in a range from an offset address to an object end identifier, to the image forming apparatus.
An access table creating means for creating an access table including a set of a page number and an offset address corresponding to each content object included in the page of the page number;
Transmitting means for transmitting the access table to the image forming apparatus and transmitting a content object corresponding to the offset address to the image forming apparatus in response to one or more offset addresses received from the image forming apparatus;
An information processing apparatus comprising:   The information processing apparatus according to claim 1, wherein the content object includes a content object in which a rendering command is described, and a resource object that indirectly references a font or an object. In an image forming apparatus including a communication unit, a printing unit, and a control unit, the control unit includes:
A set of page number and offset address corresponding to each content object included in the page identified by this page number is received from the outside via the communication means, and an access table provided for each page is received.
For each page number, an offset address belonging to the page number is acquired from the access table and transmitted to the outside via the communication means.
A content object corresponding to the offset address is received from the outside via the communication means,
An image is formed on a sheet by developing the content object into a bitmap and supplying it to the printing unit.
An image forming apparatus. An information processing apparatus according to claim 1 or 2,
An image forming apparatus according to claim 3;
An image forming system comprising: In an image forming apparatus including a print data input unit, a printing unit, and a control unit,
The print data input means includes
The contents of each page are described by an indirect object with an identifier, the content object with an identifier is described in each indirect object, and the identifiers of the indirect object and the content object are associated with the offset address in the cross-reference table, An electronic document in which the content of the corresponding indirect object or content object is described in the range from the offset address to the object end identifier;
An access table having a set of a page number and an offset address corresponding to each content object included in the page of the page number for each page;
From the outside,
The control means acquires, for each page number, an offset address belonging to the page number from the access table, acquires a content object corresponding to the offset address from the electronic document, and expands the content object into a bitmap. Forming an image on the paper by supplying to the printing unit,
An image forming apparatus.