Patent Publication Number: US-8537426-B2

Title: Image processing method, image processing apparatus, and computer-readable storage medium for computer program for generating an integrated duplicate by printing images of a plurality of documents on a single sheet of recording paper or a plurality of continuously-fed sheets of recording paper

Description:
This application is based on Japanese Patent Application No. 2009-192566 filed on Aug. 21, 2009, the contents of which are hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image processing method, an image processing apparatus, and a computer-readable storage medium for computer program for processing an identification code such as a QR Code when copies are made in a booklet copy mode or an N-in-1 copy mode. 
     2. Description of the Related Art 
     Conventionally, it is possible for an MFP (Multi Function Peripheral) that serves as a copier or a digital multi functional apparatus to create a combined copy by printing images of a plurality of documents on a single sheet of recording paper or a plurality of continuously-fed sheets of recording paper, i.e., create a combined copy or booklet copy. 
     In recent years, an identification code such as the QR Code (Registered Trademark) has been added to various printed matters or products for the management of such printed matters or products. Along with this trend, there have been also proposed MFPs that are provided with a function of processing the identification code. 
     The image data processing apparatus disclosed in JP-H07-114299-A controls the output of images based on additional information having higher priorities among those read out from a plurality of document images, and creates and outputs on paper new additional information based on the individual pieces of additional information that are read out. 
     Further, when an image forming apparatus disclosed in JP-2007-081936-A makes combined copies using a plurality of documents having individual two-dimensional bar codes added thereto, the apparatus creates new two-dimensional bar codes from the individual two-dimensional bar codes and prints the resultants together with image data on output paper. 
     The documents used for the combined copy or the booklet copy are made up of a plurality of documents related to one another. For this reason, the identification codes attached to the individual documents are sometimes identical. When the plurality of documents having an identical identification code attached thereto are copied in the combine copy mode, an identical identification code is attached to individual pages of the copy, which results in a finished copy including in its entirety a plurality of identical identification codes. When such a finished copy is used for a generation copy, an MFP is to detect and analyze a plurality of identical identification codes. 
     For example, assuming that a brochure is produced using eight A4 size documents to which individual identification codes including transmission prohibiting information are added. In this case, the documents are copied in a booklet copy mode to obtain two sheets of finished copy (duplex-sided copy) which are then folded in two and bound to be finished as an eight-page A5-size brochure. Images of the documents are reduced in size and copied into individual pages. The copied images include the identification codes attached to the individual documents as they are. 
     Next, when the brochure is further duplicated, which means that when the second generation copy of the documents from which the brochure is duplicated is made, a user places the two sheets of copies that form the brochure in the MFP and enters instructions for copying on an operation panel. The MFP, by receiving the instructions, reads the images on the two sheets of copies and, in addition, detects eight identification codes in total to perform analysis and processing. 
     However, since all of the images on the two sheets of copies that have been read based on the instructions for copying by the user are dealt with as a single process or job, it is sufficient to perform control on the job based on the single identification code. Therefore, the remaining seven identification codes are redundant and unnecessary. 
     In this way, conventionally, unnecessary identification codes are detected, analyzed, and processed when the generation copies are made, which consumes undue period for image processing. 
     SUMMARY OF THE INVENTION 
     The present invention is made in view of the foregoing problem, and it is an object of the present invention to reduce wasteful time by reducing unnecessary identification codes, which is otherwise required for a work such as processing for analyzing identification codes when a generation copy is made. 
     According to an aspect of the present invention, an image processing method for generating an integrated duplicate by printing images of a plurality of documents on a single sheet of recording paper or a plurality of continuously-fed sheets of recording paper, the method includes a first step of reading each of the plurality of documents and obtaining image data corresponding thereto, a second step of detecting identification codes included in the plurality of documents from individual pieces of the image data, a third step of extracting image data including identification codes that are identical with one another, and a fourth step of keeping at least one of the identification codes included in the image data extracted in the third step and deleting the identification codes other than said at least one of the identification codes. 
     The third step may be arranged to extract an image data group made up of one or more pieces of image data including an identical identification code or identical output processing information included in the identification codes. 
     These and other characteristics and objects of the present invention will become more apparent by the following descriptions of preferred embodiments with reference to drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an example of a configuration of a network system including an image forming apparatus. 
         FIG. 2  is a diagram illustrating an example of a hardware configuration of an image forming apparatus. 
         FIG. 3  is a block diagram illustrating an example of a functional configuration of an image forming apparatus. 
         FIGS. 4A-4C  illustrate an example in which 2-in-1 copies are made from four documents GK. 
         FIGS. 5A-5C  illustrate an example of a process in which a booklet copy is made from eight documents. 
         FIGS. 6A-6C  illustrate another example of a process in which a booklet copy is made from eight documents. 
         FIGS. 7A and 7B  illustrate an example in which copies are made on two different sheets from facing pages of a book 
         FIG. 8  is a flowchart illustrating a flow of processes in an image forming apparatus. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In  FIG. 1 , an image forming apparatus  1  is connected to a personal computer  4  etc. through a network  3 . The network  3  includes LANs, WANs, the Internet, public lines, dedicated lines, or the like. 
     The image forming apparatus  1  is an apparatus called an MFP (Multi Function Peripheral) and is configured to integrate therein a variety of functions such as copying, faxing, network printing, scanning, and a box function. Particularly, the image forming apparatus  1  according to this embodiment is capable of performing an integrated copy such as a 2-in-1 copy, a booklet copy in which a plurality of copies are produced and arranged into a booklet style, and the like. The image forming apparatus  1  is also capable of processing an identification code SC such as a QR (Quick Response) Code which is one type of two-dimensional bar codes. 
     As illustrated in  FIG. 1 , the image forming apparatus  1  is provided with an automatic document feeder (ADF)  12 , an image reader  13 , an operation panel  14 , a paper feeder  15 , a print engine  16 , a control processor  17 , and so on. 
     The automatic document feeder  12  automatically feeds documents placed on a document tray in accordance with the instructions. 
     The image reader  13  scans the surface of a document that has been fed thereto according to the size of a document GK and outputs image data D 1 . 
     The operation panel  14  is configured of a display section (touch panel) for displaying an operational status of the image forming apparatus  1  and displaying operational screens of various functions and a variety of keys for operating the image forming apparatus  1 . 
     The paper feeder  15  feeds out a sheet of paper stored in a paper feeding cassette and feeds the sheet of paper to the print engine  16 . 
     The print engine  16 , after the image data D 1  or image data externally transmitted has undergone various processes, prints an image from the resultant image data on paper by the electrophotographic process. 
     The control processor  17  controls an entirety of the image forming apparatus  1  based on commands received on the operation panel  14  and performs various image processing. In this embodiment, the outlines of the functions that are realized by the control processor  17  are described below. 
     Specifically, the control processor  17  is provided with a first portion that reads documents and obtains image data of the individual documents; a second portion that detects, from each piece of the image data, an identification code included in the document and containing output processing information which is information about an output processing method applied to the image data; a third portion that extracts an image data group consisting of image data having identical output processing information that is included in the identification code; and a fourth portion that determines at least one piece of representative image data from among the image data included in each of the image data groups and deletes identification codes attached to other image data than the piece of representative image data. 
     It is also possible to provide a fifth portion that generates a modified identification code including the output processing information which has been included in the deleted identification code, and adds the generated modified identification code to the individual pieces of representative image data in place of the identification code included in the individual pieces of representative image data. 
     The modified identification code may include information that identifies image data from which the identification code attached thereto has been deleted, among image data of the image data group including therein the piece of representative image data to which the modified identification code is attached. 
     The fourth portion may be arranged not to delete the identification code from such image data if the output processing information of such image data includes information indicating that duplication or transmission of a part or a whole of image data is prohibited. 
     It is also possible to organize the second portion so that it obtains positional information that identifies a position of the identification code in the document image, and organize the fifth portion so that it determines a position in which the modified identification code is added based on the positional information. 
     The fifth portion is capable of generating the modified identification code in a size at a predetermined scaling factor relative to the identification code and adding the resultant modified identification code. 
     The image forming apparatus  1  may be arranged to divide a document image of a single document into a plurality of divided images, print the divided images onto different sheets of recording paper individually, and thereby produce a duplicate of the document image divided on a plurality sheets of recording paper. In this case, the image forming apparatus  1  may be provided with: a first portion that reads a document and obtains image data corresponding to the image of the document; a second portion that detects an identification code which is included in the document and contains therein information about the output processing method of the document; and a fifth portion that performs editing so that each of the divided images includes the detected identification code. 
     The function of the control processor  17  will be described in details later. 
       FIG. 2  is a diagram illustrating an example of a hardware configuration of the image forming apparatus  1 . 
     A QR Code will be taken as an example of the identification code SC that is included in or added to the document. However, it is also possible to use two-dimensional bar codes other than the QR Code, one-dimensional bar codes such as ordinary bar codes, and other types of codes that can be detected and analyzed in the image forming apparatus  1 . 
     Referring to  FIG. 2 , the image forming apparatus  1  is provided with a Central Processing Unit (CPU)  201 , a Random Access Memory (RAM)  202 , a Read-Only Memory (ROM)  203 , a hard disk  204 , a control circuit  205 , an image reader  13 , an operation panel  14 , a print engine  16 , and so on. Each of these portions is connected to each another through a bus  206 . 
     The CPU  201  executes various programs (computer programs) stored in the ROM  203  to thereby perform image processing including a process on an identification code, which will be described later, and other processes and functions of different kinds. 
     The RAM  202  serves to store data therein temporarily. In this embodiment, the RAM  202  memorizes, for example, such information as the positional information of the identification code SC and restoration information of the identification code SC. 
     The ROM  203  stores therein, in advance, various programs and operation messages required for the operation of the image forming apparatus  1 . 
     The hard disc  204  stores therein the image data D 1  outputted from the image reader  13 , and other data or programs. 
     The control circuit  205 , in conjunction with the CPU  201 , controls the hard disk  204 , the image reader  13 , the operation panel  14 , the print engine  16 , and so on. 
     The control processor  17  is configured of the CPU  201 , the RAM  202 , the ROM  203 , the hard disk  204 , the control circuit  205 , and the like. 
     Next, a description will be given of the functions that are realized by the control processor  17 . 
       FIG. 3  is a block diagram illustrating a functional configuration of an image processing portion GS that is implemented by the control processor  17 , according to a first embodiment. 
     Referring to  FIG. 3 , the image processing portion GS is provided with a code detection/analysis portion  41 , an image group extraction portion  42 , an image editing portion  44 , a representative image determination portion  45 , a code deletion portion  46 , a code generation portion  47 , a code addition portion  48 , and the like. 
     The image reader  13  reads one or more sheets of document GK and outputs image data D 1 . If the document GK is made up of a plurality of sheets, a quantity of the image data D 1  thus obtained corresponds to the number of the sheets of the document GK. In the example illustrated in the upper part of  FIG. 3 , a plurality of pieces of image data D 1 , i.e., D 1   a , D 1   b , D 1   c , and D 1   d , corresponding to four sheets of document GK are obtained. When copies are made in an integrated copy mode or a booklet copy mode, the plurality of sheets of the document GK are read in succession as a group of a series of documents. The image data D 1  thus obtained from the document GK is forwarded to the code detection/analysis portion  41  and the image editing portion  44 . 
     A region determination process, an edge enhancement process, an image quality adjustment process, and other various types of input image processing are performed as necessary on the image data D 1 . 
     The code detection/analysis portion  41  detects, from the pieces of the image data D 1 , identification codes SC, i.e., SCa to SCd, which are included in the document GK, and analyzes them. In other words, the code detection/analysis portion  41  detects the presence or absence of an identification code SC that is added to the original image of the document GK and analyzes what is indicated by the identification code SC if the identification code SC is present. 
     Identification code information DS which is a piece of information representing an image shape, a type, contents, a size, and the like of the identification code SC is obtained as a result of analyzing the identification code SC. The code detection/analysis portion  41  also obtains, as a part of the identification code information DS, positional information DST that identifies a position of the detected identification code SC in the document GK to which the identification code SC originally belongs. 
     The identification code SC, i.e., the identification code information DS, includes such information as outputting conditions of the document GK to which this identification code SC is added, and an operational mode relating to how the document GK is processed, for example, information (output processing information) relating to an output processing method of the document GK. Specifically, such information may include a condition for making a 2-in-1 copy, a condition for making a booklet copy, copy prohibiting information, copy restriction information, transmission prohibiting information, transmission restriction information, E-mail attachment prohibiting information, E-mail attachment restriction information, and so on. Such information may also include a type of the document GK, the number of sheets or pages of the entire document GK, information on whether the document GK is in color or in black and white, document creator information, document creation time and date information, and so on. 
     The image group extraction portion  42  extracts an image data group DL made up of image data D 1  of which the identification code information DS is identical. The number of the image data groups DL may be one, two or more, or sometimes nil. It is not necessary to extract the image data D 1  itself, but it is simply a matter of grouping together such image data D 1  or document GK having an identical identification code included therein among a plurality of pieces of image data D 1  or a plurality sheets of document GK. For example, the image data group DL may be in a form of a list of image data D 1  or document GK having identical identification code information DS. 
     In determining whether the identification code information DS is identical or not with each another, it is possible to determine that the identification code information DS is identical in various cases including where all of the identification code information DS included in the identification codes SC is identical, a part of the identification code information DS is identical, particularly the output processing information is identical, or a part of the output processing information is identical. Alternatively, it is also possible to compare the shapes of the identification codes SC and determine that the identification code information DS is identical if there is no significant difference among the shapes. It is also possible to set conditions in advance to determine in which case the identification codes SC or the identification code information DS is assumed identical. 
     For example, according to an example of a document GK illustrated in the upper part of  FIG. 3 , the identification codes SC (SCa, SCb, SCc, and SCd) added to the image data D 1  (D 1   a , D 1   b , D 1   c , and D 1   d ), respectively, are identical with each other. Consequently, the identification code information DS included in individual identification codes SC is also identical with each another. In this case, the four pieces of image data D 1   a , D 1   b , D 1   c , and D 1   d  form a group as the image data group DL whose quantity is one. 
     The image editing portion  44  performs image editing on the image data D 1  to cope with various modes of copies such as a 2-in-1 copy, a booklet copy, a double-sided copy, a scaled copy, a book divided copy (copies are made on two different sheets from facing pages of a book). The image editing portion  44  also performs deletion and addition of an identification code SC from and to the image data D 1 . To be specific, the image editing portion  44  deletes (erases) an identification code SC in a predetermined page in the image data D 1  based on a command from the code deletion portion  46 . The image editing portion  44  also adds a modified identification code SCS to a predetermined page in the image data D 1  based on a command from the code addition portion  48 . 
     According to an example of a duplicate CP illustrated in the upper part of  FIG. 3 , image editing for a booklet copy is performed on image data D 1  (D 1   a , D 1   b , D 1   c , and D 1   d ) obtained from the document GK. To be more specific, the image editing portion  44  deletes each of the identification codes SC (SCa, SCb, SCc, and SCd) included in the image data D 1  (D 1   a , D 1   b , D 1   c , and D 1   d ). Then, a modified identification code SCS, which is a modified version of the identification code, is added to the image data D 1   a  having the smallest page number among the image data D 1  (D 1   a , D 1   b , D 1   c , and D 1   d ) from which the identification codes SC have been deleted. 
     The representative image determination portion  45  determines, for each of the image data groups DL, at least one piece of representative image data DLD among image data D 1  included in each of the image data groups DL. The representative image data DLD may be one or more pieces. Various methods may be taken for determining the representative image data DLD by considering details of editing performed by the image editing portion  44 . For example, according to the example of the duplicate CP illustrated in the upper part of  FIG. 3 , the image data D 1   a  having the smallest page number among the image data D 1  included in the image data group DL is taken as the representative image data DLD. 
     Alternatively, the representative image data DLD may be designated by user&#39;s operation through the operation panel  14 . For example, the user may designate the image data D 1   a  in the first page as the representative image data DLD so that only the identification code SCa added to the first page remains. Instead, the user may designate the image data Did in the last page as the representative image data DLD so that only the identification code SCd added to the last page remains. 
     It is also possible to make an arrangement such that the representative image determination portion  45  generates page designation information DLP that indicates image data D 1  other than the representative image data DLD based on the representative image data DLD. 
     According to the example of the duplicate CP illustrated in the upper part of  FIG. 3 , since the representative image data DLD is the image data D 1   a  in the page having the smallest page number, the page designation information DLP is generated to indicate other image data D 1   b , D 1   c , and D 1   d . Here, it is possible to use, for example, a reference to a page or a page number to indicate the representative image data DLD and for the page designation information DLP to make designation among all pieces of the image data D 1  corresponding to a group of a series of documents. 
     The code deletion portion  46  instructs the image editing portion  44  to delete the identification code SC based on: the image shape of the identification code SC indicated in the identification code information DS; the positional information DST; the representative image data DLD or the page designation information DLP from the representative image determination portion  45 ; whether or not the modified identification code SCS generated in the code generation portion  47  is added to the representative image data DLD, or the like. 
     The code generation portion  47  generates, for identification code information DS of an identification code SC that is detected by the code detection/analysis portion  41 , a modified identification code SCS including information about the identification code SC to be deleted. The information about the identification code SC to be deleted includes information that indicates a page to be deleted. 
     According to the example of the duplicate CP illustrated in the upper part of  FIG. 3 , the identification codes SCa, SCb, SCc, and SCd included respectively in the image data D 1   a , D 1   b , D 1   c , and D 1   d  are deleted, and amongst which a modified identification code SCS is added to the image data D 1   a . The modified identification code SCS includes information indicating individual pages corresponding to the image data D 1   b , D 1   c , and D 1   d  from which the identification codes SCb, SCc, and SCd are deleted, respectively. 
     The modified identification code SCS may include, in addition to information about the identification codes SCb, SCc, and SCd, other information indicating that it is a modified identification code SCS, indicating representative image data DLD, or indicating an image data group DL to which the modified identification code SCS belong. 
     The code generation portion  47  is capable of generating a modified identification code SCS in a size according to a predetermined scaling factor relative to its original identification code SC. For example, the scaling factor based on the size of the identification code SC may be set equal to a scaling factor for enlargement or reduction of size applied to the image data D 1  by the image editing portion  44 , i.e., equal to the scaling factor of copy. In this case, the appearance of the image of the duplicate CP which is printed is the same as that of the original document GK. In addition, the scaling factor applied to the identification code SC may be set to “1” regardless of the scaling factor applied to copying. In this case, even if the image based on the image data D 1  is reduced in size, the image of the modified identification code SCS is not reduced, which makes it easy to detect and analyze the modified identification code SCS when a generation copy is made. 
     The code addition portion  48  instructs the image editing portion  44  to add a modified identification code SCS based on the information about an image shape of the identification code SC indicated in the identification code information DS, the positional information DST, and the representative image data DLD or the page designation information DLP from the representative image determination portion  45 . 
     At the page into which the modified identification code SCS is added by the code addition portion  48 , i.e., at the page of the representative image data DLD, the original identification code SC is deleted as described before. For each piece of image data D 1  designated as the representative image data DLD, a modified identification code SCS is generated and added (re-added) thereto in place of the identification code SC which is originally included in each piece of the representative image data DLD. In this case, the modified identification code SCS includes information about the identification code SC that has been deleted based on the page designation information DLP. 
     According to the example of the duplicate CP illustrated in the upper part of  FIG. 3 , the original identification code SCa has been deleted, and a modified identification code SCS is added instead in the page of the image data D 2   a  (representative image data DLD) to which the modified identification code SCS is added. 
     In this way, the image editing portion  44  edits the image data D 1  (D 1   a , D 1   b , D 1   c , and D 1   d ), and the image data D 2  (D 2   a , D 2   b , D 2   c , and D 2   d ) on which editing has been performed is outputted, printed on paper by the print engine  16 , and discharged as the duplicate CP. 
     According to example of the document GK and the duplicate CP illustrated in the upper part of  FIG. 3 , for example, individual image data D 1   a , D 1   b , D 1   c , and D 1   d  of the four sheets of documents GK in A4 size are reduced in size and printed on double sides of one A5 size sheet of paper as image data D 2   a , D 2   b , D 2   c , and D 2   d  by making a booklet copy. In this case, a duplicate CP formed of four pages is obtained by folding the printed paper in two. In place of four identification codes SCa to SCd included in the four sheets of the document GK, a modified identification code SCS is printed on the first page of the duplicate CP instead of the identification code SCa, and the identification codes SC are deleted from the second to fourth pages having solely their individual original images printed thereon without addition of modified identification codes SCS. 
     Next, the processing performed on the identification code SC by the image processing portion GS will be described with reference to specific examples. 
       FIGS. 4A-4C  illustrate how two duplicates CP 1  and CP 2  are obtained from four documents GK 1 -GK 4  by performing 2-in-1 copying. 
     As illustrated in  FIG. 4A , the documents GK 1 -GK 4  include the identification codes SC 1 -SC 4 , respectively in addition to their individual original images GZ 1 -GZ 4 . Among these identification codes SC 1 -SC 4 , the identification codes SC 1  and SC 2  are identical with each other but different from the identification codes SC 3  and SC 4 , and, in addition, the identification codes SC 3  and SC 4  are different from each other. 
     Referring to  FIG. 4B , since copies are made in the 2-in-1 copy mode, the documents GK 1  and GK 2  are reduced in size and printed next to each other on one side of a first sheet of paper, and the documents GK 3  and GK 4  are reduced in size and printed next to each other on one side of a second sheet of paper. 
     The image processing portion GS detects that the identification codes SC 1  and SC 2  are identical, and that the image data D 1   a  corresponding to the document GK 1  and the image data D 2   b  corresponding to the document GK 2  belong to a single image data group DL. Then, the image data Dia printed on a page having a smaller page number than the other is determined to be a representative image data DLD. This results in deletion of the identification code SC 2  that has been included in the document GK 2 . Also, a modified identification code SCS 1  including information indicating that the identification code SC 2  has been deleted and it is a 2-in-1 copy of the two documents GK 1  and GK 2  is generated and printed in a manner to replace the original identification code SC 1  included in the document GK 1 . This means that the original identification code SC 1  is deleted, and, in place of this, the modified identification code SCSI is generated and printed. In this way, the duplicate CP 1  is obtained. 
     The documents GK 3  and GK 4  have the identification codes SC 3  and SC 4 , respectively, which are different from each other. Therefore, the identification codes SC 3  and SC 4  are not deleted and are printed as is together with the individual images GZ 3  and GZ 4 . In this way, the duplicate CP 2  is obtained. 
     Accordingly, the duplicate CP 1  does not include two identification codes SC that are identical with each other. As a result of this, when a generation copy is made, specifically, when the duplicate CP 1  is used as a new document GK and copied, it is possible to detect only one modified identification code SCS 1  and perform analysis and processing thereon. Therefore, it is possible to reduce a wasteful time required for analyzing two identification codes and thereby reduce a processing time. In this way, according to this embodiment, it is possible to reduce unnecessary identification codes. 
     Moreover, since the modified identification code SCS 1  includes an indication that the document GK 2  on the second page once had an identification code SC, it is also possible to restore the original state later. Alternatively, it is also possible to leave the identification code SC 1  as is and simply delete the identification code SC 2 . 
     As illustrated in  FIG. 4C , alternatively, it is also possible to arrange the image of the document GK 2  as the representative image data DLD instead of the document GK 1 . In this case, in the duplicate CP 1 B corresponding to the document GK 1 , the identification code SC 1  is deleted, and the modified identification code SCS 2  which is generated for the document GK 2  is added. 
     In the example described above, the scaling factor applied to the modified identification codes SCS 1  and SCS 2 , and the identification codes SC 3  and SC 4  is the same as the reduction ratio applied to the images GZ 1 -GZ 4 . However, reducing the modified identification codes SCS or the identification codes SC in size may make it difficult to analyze them. As a preventive measure, it is also possible to print the modified identification codes SCS 1  and SCS 2 , and the identification codes SC 3  and SC 4  at a 100% scaling factor without applying reduction thereto. Instead of 100% scaling factor, a reduction factor larger than the reduction factor applied to the copying of a document may be used for printing the identification codes. Alternatively, a scaling factor for enlargement may be used. 
     It is also possible to apply a scaling factor identical with the reduction factor used for copying to the identification codes SC 3  and SC 4 . In addition, it is also possible to apply a 100% scaling factor, a scaling factor larger than reduction used for the copying, or a scaling factor for enlargement to the modified identification code SCS 1  or SCS 2 . 
     In the example, it is assumed that the positions in which the modified identification codes SCS 1  and SCS 2 , and the identification codes SC 3  and SC 4  are printed are the relative positions of the original identification codes SC 1 -SC 4  to the images GZ 1 -GZ 4 . However, this may be changed. For example, it is possible to determine the positions regardless of the positions of the original identification codes SC 1 -SC 4  so that the modified identification codes SCS 1  and SCS 2 , and the identification codes SC 3  and SC 4  are printed in specific positions in the duplicates CP. In such a case, it is also possible to specify the positions of only the modified identification code SCS 1  or SCS 2 . 
     In the case where copy prohibiting information or transmission prohibiting information is included in the identification codes SC 1  and SC 2 , it is also possible to print the identification codes SC 1  and SC 2  without deleting them. 
     In the example described above, a case where 2-in-1 copying is made is described. However, the identification code SC can also be processed in the similar manner in the case of 4-in-1 or N-in-1 (where N is an arbitrary integer) copying. 
     Next,  FIGS. 5A-5C  illustrate how two duplicates CP 11  and CP 12  are obtained by copying eight documents GK 11 -GK 18  in a booklet copy mode. The two duplicates CP 11  and CP 12  are placed with one on top of the other and folded in two to thereby make one booklet CPS 1 . 
     As illustrated in  FIG. 5A , the documents GK 11 -GK 18  include identification codes SC 11 -SC 18  in addition to original images GZ 11 -GZ 18 , respectively. These individual identification codes SC 11 -SC 18  are all identical with one another. 
     Referring to  FIG. 5B , since it is a booklet copy, the first two documents GK 11  and GK 12  are reduced in size, laid side by side, and printed on one side of a first sheet of paper; the last two documents GK 17  and GK 18  are reduced in size, laid side by side, and printed on the other side of the first sheet of paper; and the remaining documents GK 13 -GK 16 , two as a set, are reduced in size, laid side by side, and printed on two sides of a second sheet of paper, respectively as a set. 
     It is assumed that the image processing portion GS detects that the identification codes SC 11 -SC 18  are identical with one another and that individual pieces of image data corresponding to the documents GK 11 -GK 18 , respectively, belong to a single image data group DL. Then, the image data corresponding to the document GK 11  having the smallest page number is determined to be representative image data DLD. This results in deletion of the identification codes SC 12 -SC 18  that have been included in the documents GK 12 -GK 18 . Also, a modified identification code SCS 11  including information indicating that the identification codes SC 12 -SC 18  have been deleted and it is a booklet copy of the eight documents GK 11 -GK 18  is generated and printed in a manner to replace the original identification code SC 11  included in the document GK 11 . As a result of this, the duplicates CP 11  and CP 12  can be obtained. As illustrated in  FIG. 5C , the two duplicates CP 11  and CP 12  are folded in two to thereby make a single booklet CPS 1 . 
     Consequently, the duplicates CP 11  and CP 12  do not include identical identification codes SC but include only a single modified identification code SCS 11 . This makes it possible to detect, analyze, and process only one modified identification code SCS 11  when a generation copy is made. Therefore, it is possible to reduce the processing time. 
     Alternatively, it is possible to leave the identification code SC 11  intact without generating the modified identification code SCS 11  and simply delete the identification codes SC 12 -SC 18 . 
     Also, in this example, various scaling factors and the printing positions may be applied to the modified identification code SCS 11  as in the case of the example illustrated in  FIGS. 4A-4C . 
     Next,  FIGS. 6A-6C  illustrate, as in the case of the example illustrated in  FIG. 5A-5C , how eight documents GK 21 -GK 28  are copied in a booklet copy mode to obtain two sheets of duplicates CP 21  and CP 22 . The two duplicates CP 21  and CP 22  are placed with one on top of the other and folded in two to thereby make one booklet CPS 2 . 
     As illustrated in  FIG. 6A , documents GK 21 -GK 28  individually include original images GZ 21 -GZ 28  and identification codes SC 21 -SC 28 . Among these identification codes SC 21 -SC 28 , the identification codes SC 21 , SC 22 , SC 27 , and SC 28  are identical with one another, and the identification codes SC 23 , SC 24 , SC 25 , and SC 26  are identical with one another. 
     The image processing portion GS detects that the identification codes SC 21 , SC 22 , SC 27 , and SC 28  are identical with one another, and that the identification codes SC 23 , SC 24 , SC 25 , and SC 26  are identical with one another. Here, it is assumed that individual pieces of image data corresponding to the documents GK 21 , GK 22 , GK 27 , and GK 28  belong to an image data group DL 1 , and individual pieces of image data corresponding to the documents GK 23 , GK 24 , GK 25 , and GK 26  belong to another image data group DL 2 . 
     Then, the image data of the document GK 21  having the smallest page number is determined to be representative image data DLD 1  for the image data group DL 1 . This results in deletion of the identification codes SC 22 , SC 27 , and SC 28  included respectively in the documents GK 22 , GK 27 , and GK 28  as illustrated in  FIG. 6B . At the same time, a modified identification code SCS 21  including information indicating that the identification codes SC 22 , SC 27 , and SC 28  have been deleted is generated and printed in a manner to replace the identification code SC 21  included in the document GK 21 . 
     Also, the image data of the document GK 23  having the smallest page number is determined to be representative image data DLD 2  for the other image data group DL 2 . This results in deletion of the identification codes SC 24 , SC 25 , and SC 26  included respectively in the documents GK 24 , GK 25 , and GK 26 . At the same time, a modified identification code SCS 22  including information indicating that the identification codes SC 24 , SC 25 , and SC 26  have been deleted is generated and printed in a manner to replace the identification code SC 23  included in the document GK 23 . 
     In this way, the duplicates CP 21  and CP 22  are obtained. 
     Then, as illustrated in  FIG. 6C , the two duplicates CP 21  and CP 22  are folded in two to make the booklet CPS 2 . 
     As a result of this, it is possible to reduce unnecessary identification codes SC and processing time. 
     Next, a description will be given of a case in which an image of a single document GK is divided into a plurality of images. 
       FIGS. 7A and 7B  illustrate how a single document GK 31  is copied in a book divided copy mode (copies are made on two different sheets from facing pages of a book) to obtain two duplicates CP 31  and CP 32 . 
     As illustrated in  FIG. 7A , the document GK 31  has two images GZ 31  and GZ 32  drawn on the left and right sides thereof. The document GK 31  is formed of, for example, two facing left and right pages when a book is opened. The document GK 31  has an identification code SC 31  drawn in right-upper portion thereof. 
     In  FIG. 7B , since this is a copy in a book divided copy mode, the image of the document GK 31  is divided into the images GZ 31  and GZ 32  and printed on separate sheets of paper. In other words, the divided image GZ 31  is printed on a first sheet of paper, and the divided image GZ 32  is printed on a second sheet of paper. 
     During such a process, the image editing portion  44  performs editing so that the detected identification code SC 31  is included in (added to) both the divided images GZ 31  and GZ 32 . 
       FIG. 7B  illustrates the duplicates CP 31  and CP 32  having the divided images GZ 31  and GZ 32 , and identification codes SC 31 A and SC 31 B identical with the identification code SC 31  printed thereon, respectively. 
     The size of the document GK 31  is A3, and the size of the duplicates CP 31  and CP 32  is A4. This means that the sizes of the images GZ 31  and GZ 32  of the duplicates CP 31  and CP 32  are identical with those of the images GZ 31  and GZ 32  of the document GK 31  (at a 100% scaling factor). 
     As described above, when a copy is made in a book divided copy mode, identification codes SC are added individually to the duplicates CP obtained as a result of the divided copy. Consequently, when the individual duplicates CP are copied independently from each other in terms of generation copy, it is possible to perform printing control based on the identification codes SC. 
     In the example described above, the identification codes SC 31 A and SC 31 B that are identical with the identification code SC 31  are printed in each of the duplicates CP 31  and CP 32 . Instead, however, it is also possible to generate a modified identification codes SCS including information indicating that the copy is resulted from the book divided copy mode and other pieces of information, and print the generated modified identification codes SCS on the individual duplicates CP 31  and CP 32 . 
     In the example described above, the scaling factor applied to the identification codes SC 31 A and SC 31 B is 100% relative to the original identification code SC 31  because the divided images GZ 31  and GZ 32  are of the same size as the original image. Accordingly, any subsequent analysis of the identification codes SC 31 A and SC 31 B will not become difficult. Even if the scaling factor applied to the divided images GZ 31  and GZ 32  is not 100%, the scaling factor applied to the identification codes SC 31 A and SC 31 B may be set at 100%. For example, if the scaling factor applied to the divided images GZ 31  and GZ 32  is for reducing the image in size, the scaling factor applied to the identification codes SC 31 A and SC 31 B may be set at 100%, which prevents the subsequent analysis of the identification code from becoming difficult. On the other hand, if the scaling factor applied to the divided images GZ 31  and GZ 32  is for enlarging the image in size, the scaling factor applied to the identification codes SC 31 A and SC 31 B may be set at 100% or at the scaling factor as applied to the images GZ 31  and GZ 32 . 
     The positions of the identification codes SC 31 A and SC 31 B may be determined in accordance with the position of the original identification code SC 31 , the size of the duplicates CP 31  and CP 32 , a state of the images GZ 31  and GZ 32 , and the like. 
     Next, referring to a flowchart, a description will be given of a process flow in the image forming apparatus  1 . 
     In  FIG. 8 , images of document GK are read, and image data D 1  thereof is obtained (# 11 ). It is detected whether identification code SC is included or not (# 12 ). If the identification code SC is included (Yes in # 12 ), the identification code SC is analyzed (# 13 ), and it is determined whether there are identical identification codes SC (# 14 ). 
     Determining whether or not there are identical identification codes SC means such cases as whether the shapes of the identification codes SC are identical; pieces of identification code information DS are all identical; a part of the identification code information DS, e.g., output processing information, is identical; and the like. There is also a case where there are a plurality of groups of image data, i.e., image data groups DL, each of which corresponds to each document GK having identical identification code SC. 
     If there are identical identification codes SC (Yes in # 14 ), an identification code SC serving as a representative is kept, and others are deleted (# 15 ). At the same time, a modified identification code SCS that will replace the identification code SC serving as a representative is generated as required; the original identification code SC is deleted; and the generated modified identification code SCS is added instead. It is possible to add various pieces of information to the modified identification code SCS. It is possible to arbitrarily decide which identification code SC is designated as a representative and the number of such identification codes. 
     Image editing is performed according to the specified copy mode (# 16 ), and printing is performed based on the edited image (# 17 ). 
     According to the embodiment, it is possible to reduce wasteful time by reducing unnecessary identification codes, which is otherwise required for a work such as processing for analyzing identification codes when a generation copy is made. 
     In the embodiment described above, the image reader  13 , the code detection/analysis portion  41 , or the control processor  17  corresponds to a first portion in this invention. Furthermore, the code detection/analysis portion  41  and the image group extraction portion  42  correspond to a second portion and a third portion, respectively. The representative image determination portion  45  and the code deletion portion  46  correspond to a fourth portion. The code generation portion  47  and the code addition portion  48  correspond to a fifth portion. 
     Finally, in the embodiment described above, the configuration of all or part, the circuitry, the quantity, the details or sequence of processing of the image processing portion GS, the control processor  17 , and the image forming apparatus  1 , and the shapes, the details, the scaling factor, the position, and so on can be modified in various ways within the spirit of the present invention. The above-mentioned unique and distinguished effects can also be attained in such a case as well. 
     While the embodiments of the present invention have been shown and described, it will be understood that the present invention is not limited thereto, and that various changes and modifications may be made by those skilled in the art without departing from the scope of the invention as set forth in the appended claims and their equivalents.