Image forming apparatus and image processing method

Abstract

To perform image formation without performing reduction of image data and unnecessary deletion of an image.SOLUTION: An image forming apparatus 1 comprises a control unit 10 that acquires information on colors constituting an image formed in a restricted area in image data formed on a sheet, and when the colors or the number of colors are allowed to be used for image formation in the restricted area, causes an image forming unit 30 to form the image data including the image formed in the restricted area.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus and an image processing method. [Background technology]

[0002] Conventionally, there are image forming devices that have restrictions on a specified area of ​​a printing paper, such as "images in colors other than spot colors cannot be formed" and "images with more than a specified number of colors cannot be formed." When an image in a color other than spot colors or an image with "more than a specified number of colors" is formed in an area with such restrictions (hereinafter also referred to as a "restricted area"), the amount of toner attached becomes greater than the specified amount, which may cause a jam or the like.

[0003] Therefore, if the image to be printed in the restricted area is an image of "other than spot color" or "more than a predetermined number of colors", a process of erasing the part of the image in the image data for printing is performed in a stage prior to image formation. For example, assume that image formation in four colors, C (Cyan), M (Magenta), Y (Yellow), and K (Key plate (Black)), or image formation in one spot color is permitted in a range of 4 mm to 6 mm from the leading edge of the paper. Assume that an image in five colors, CMYK and spot color, is included in the range of 4 mm to 6 mm from the leading edge of the paper in the image data (restricted area). In this case, the image in the area corresponding to the range of 4 mm to 6 mm from the leading edge of the paper is erased from the image data. In other words, an image loss occurs in the print image.

[0004] Patent document 1 discloses an image forming device that includes a judgment unit that judges whether an image area detected from read data fits within an image formation area, a processing unit that performs the necessary processing to fit the image area within the image formation area if the judgment unit judges that the image area does not fit within the image formation area, and an image forming unit that forms an image of the image area processed by the processing unit within the image formation area. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5669703 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the technology described in Patent Document 1, the processing unit performs processing such as moving or reducing the image area, so the printed image differs from the original image data (for example, the read data in Patent Document 1).

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to enable image formation without reducing image data or erasing unnecessary parts of an image. [Means for solving the problem]

[0008] In order to achieve at least one of the above-mentioned objects, an image forming apparatus reflecting one aspect of the present invention is provided with a control unit that obtains color information constituting an image to be formed in a restricted area where the color or number of colors is limited from image data of an image to be formed on a recording material, and when it is determined that the color or number of colors is such that image formation in the restricted area is permitted, causes an image forming unit to form image data including the image to be formed in the restricted area. Effect of the Invention

[0009] According to the present invention, it becomes possible to form an image without reducing image data or erasing unnecessary parts of the image. Problems, configurations and effects other than those described above will become apparent from the following description of the embodiments. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram showing an outline of a conventional restricted area. [Diagram 2]FIG. 1 is a diagram showing an example of paper on which image data for printing in the related art is printed. [Diagram 3] 3 is a diagram showing an example of image data printed on the paper shown in FIG. 2. [Figure 4] 13 is a diagram showing an example of image data in which an image in a portion of an area corresponding to an area on a sheet of paper has been erased; FIG. [Diagram 5] FIG. 1 is a diagram showing an overview of image processing according to an embodiment of the present invention. [Figure 6] 1 is a schematic diagram illustrating an example of the overall configuration of an image forming apparatus according to an embodiment of the present invention; [Figure 7] 2 is a block diagram showing an example of the configuration of a control system of the image forming apparatus according to the embodiment of the present invention; [Figure 8] 5 is a diagram showing an example of job information included in a print job transmitted from a terminal device (not shown) according to the first embodiment of the present invention. FIG. [Figure 9] FIG. 4 is a diagram showing an example of page information included in a print job according to the first embodiment of the present invention. [Figure 10] FIG. 4 is a diagram showing an example of image data information included in a print job according to the first embodiment of the present invention. [Figure 11] FIG. 4 is a diagram showing an example of image data of each color according to Example 1 of the first embodiment of the present invention. [Figure 12] 5 is a flowchart showing an example of processing at the time of start-up of the image forming apparatus according to the first embodiment of the present invention; [Figure 13] 1 is a flowchart showing an example of a procedure of image processing according to a first example of the first embodiment of the present invention. [Figure 14] FIG. 11 is a diagram showing an example of image data of each color according to Example 2 of the first embodiment of the present invention. [Figure 15] 15A and 15B are diagrams showing examples of a region on the leading end side and a region on the trailing end side in image data formed by overlapping the colors shown in FIG. 14. [Figure 16] FIG. 13 is a diagram showing image data from which an image in an area corresponding to a restricted area has been erased based on the conventional technology. [Figure 17]13A to 13C are diagrams showing examples of images formed in the restricted area on the leading end side and the area on the trailing end side before and after rotating image data by 180 degrees according to Example 2 of the first embodiment of the present invention. [Figure 18] 11 is a flowchart showing an example of a procedure of image processing according to Example 2 of the first embodiment of the present invention. [Figure 19] FIG. 11 is a diagram showing an example of image data of each color according to Example 3 of the first embodiment of the present invention. [Figure 20] 20A and 20B are diagrams showing examples of a region on the leading end side and a region on the trailing end side in image data formed by overlapping the colors shown in FIG. 19. [Figure 21] 13A to 13C are diagrams illustrating an example of forming, on a sheet, image data before and after an image shift according to Example 3 of the first embodiment of the present invention. [Figure 22] 13 is a flowchart showing an example of a procedure of image processing according to a third example of the first embodiment of the present invention. [Diagram 23] FIG. 11 is a diagram showing an overview of a restricted area according to a second embodiment of the present invention. [Figure 24] FIG. 11 is a diagram showing an example of job information according to the second embodiment of the present invention. [Diagram 25] FIG. 11 is a diagram showing an example of image data information included in a print job according to a second embodiment of the present invention. [Figure 26] 13A and 13B are diagrams illustrating examples of paper on which image data is printed according to a second embodiment of the present invention. [Figure 27] 27 is a diagram showing an example of image data formed on the paper shown in FIG. 26. [Figure 28] FIG. 11 is a diagram showing an example of image data for each color according to the second embodiment of the present invention. [Figure 29] FIG. 13 is a diagram showing image data from which an image in an area corresponding to a restricted area has been erased based on the conventional technology. [Diagram 30] 13A and 13B are diagrams showing examples of images formed in a restricted area on the leading end side and an area on the trailing end side before and after image data is rotated 180 degrees according to the second embodiment of the present invention. [Diagram 31]10 is a flowchart showing an example of a procedure for image processing according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functions or configurations are denoted by the same reference numerals, and duplicated descriptions of the components will be omitted.

[0012] Before moving on to the description of the embodiments of the present invention, the problem to be solved by the present invention will be described. Fig. 1 is a diagram showing an overview of a restricted area. The upper part of Fig. 1 shows an area SAr1 where only a spot color image can be formed, the middle part shows an area SAr2 where a spot color + CMYK four-color image can be formed, and the lower part shows an overlapping display of the areas SAr1 and SAr2.

[0013] 1, image formation is not permitted in the areas of the paper Sh that are 4.0 mm from the leading edge, 4.0 mm from the trailing edge, and 4.0 mm from each of the left and right edges in the paper feed (conveyance) direction Df. However, in the area SAr1 inside these areas, image formation is possible as long as the image is composed of only special colors.

[0014] On the other hand, in the case of the paper Sh shown in the middle of Fig. 1, the area in the paper feed direction Df that is 6.0 mm from the leading edge, 4.0 mm from the trailing edge, and 4.0 mm from each of the left and right edges is an area where image formation is not permitted. In the area SAr2 inside this area, an image of four colors (spot color + CMYK) can be formed.

[0015] In the diagram in the lower part of Fig. 1, where the areas SAr1 and SAr2 are overlapped, in the area SAr3 ranging from 4.0 to 6.0 mm from the leading edge of the paper Sh in the paper feed direction Df, that is, in the area of ​​the difference between the areas SAr1 and SAr2, only images consisting of spot colors can be formed. In other words, the area SAr3 is a restricted area where the formation of images including colors other than the spot colors is restricted.

[0016] FIG. 2 is a diagram showing an example of a sheet Sh on which image data for printing is printed. The sheet Sh shown in FIG. 2 is an A4 size (210x297 mm) sheet that is completely black. FIG. 3 is a diagram showing an example of image data printed on the sheet Sh shown in FIG. 2. The image data P shown in FIG. 3 is configured to have a size of 202x289 mm excluding the 4.0 mm margins on the top, bottom, left and right of the A4 size sheet Sh. The area PAr3 at the leading edge of this image data P in the paper feed direction Df, that is, the area in the range of 4.0 to 6.0 mm (width 2.0 mm) at the leading edge of the paper, corresponds to the restricted area SAr3 shown in FIG. 1. It is assumed that an image configured only of special colors exists in this restricted area SAr3.

[0017] In other words, the area PAr3 corresponding to the restricted area SAr3 is composed only of images in spot colors for which image formation is permitted, and therefore there is no need to erase the image in this portion. However, in conventional technology, the image formed in this area PAr3, i.e., the area corresponding to the restricted area, was unconditionally erased without any analysis of the colors constituting the image formed in the area PAr3.

[0018] Fig. 4 is a diagram showing an example of image data P' in which the image in the area PAr3 corresponding to the area SAr3 on the paper Sh has been erased. In the image data P' shown in Fig. 4, the image formed in the area SAr3 from 4.0 to 6.0 mm from the leading edge of the paper has been deleted, and it can be seen that the image data P' is a different image from the image data P shown in Fig. 3.

[0019] <Overview of Image Processing According to an Embodiment> 5 is a diagram showing an overview of image processing according to one embodiment of the present invention. In one embodiment of the present invention, the image forming apparatus analyzes an image formed in an area SAr3 of 4.0 to 6.0 mm from the leading edge of the paper. Then, if it is determined that the image is an image composed only of colors permitted to be formed in that area, for example, spot colors, the image forming apparatus prints the image formed in the area SAr3 as is, without erasing it. By carrying out such processing, it is possible to prevent defects from occurring in the printed image, and it is possible to perform printing that makes the most of the restricted area.

[0020] <Configuration of Image Forming Apparatus> Next, an image forming apparatus according to one embodiment of the present invention will be described with reference to Fig. 6. Fig. 6 is a schematic diagram showing an example of the overall configuration of an image forming apparatus 1. Note that Fig. 6 shows elements necessary for explaining the present invention or related elements, and the image forming apparatus of the present invention is not limited to the example shown in Fig. 6.

[0021] As shown in FIG. 6, the image forming apparatus 1 includes an original transport section 11, an original reading section 12, an operation display section 13, a paper feed section 20, an image forming section 30, a paper reversing section 37, and a paper discharge tray 40.

[0022] The document transport unit 11 automatically transports one or more sheets of document paper to the document reading unit 12. Note that the image forming apparatus of the present invention may be configured without the document transport unit 11. The document reading unit 12 optically reads image data from a document placed on the document table 11, and generates read image data. Note that the image forming apparatus of the present invention may be configured without the document reading unit 12.

[0023] The operation display unit 13 is a touch panel in which a touch sensor as an operation input unit and a display panel as a display unit are integrally formed. A user can perform various settings related to the image forming apparatus 1 through operations on the operation input unit of the operation display unit 13. Note that the operation input unit and the display unit may be configured separately from each other.

[0024] The paper feed unit 20 has a plurality of trays for storing paper Sh (an example of a recording material), and feeds paper Sh stored in any one of the plurality of trays to the image forming unit 30 via a conveying path 21. Note that the paper feed unit 20 may be provided with a single tray.

[0025] The image forming section 30 forms an image based on image data on the paper Sh fed from the paper feed section 20 by an electrophotographic imaging process. The image forming section 30 includes five image forming units 31S, 31Y, 31M, 31C, and 31K for forming toner images of the respective colors of S (spot color), Y, M, C, and K. The spot color S is a color used, for example, as the background color (base color) of the image.

[0026] Image forming units 31S, 31Y, 31M, 31C and 31K each include a charging unit, an LED writing unit (laser light source) (all not shown), photoconductor drums 32S, 32Y, 32M, 32C and 32K, and developing units 33S, 33Y, 33M, 33C and 33K, respectively.

[0027] The developing units 33S, 33Y, 33M, 33C, and 33K form latent images on the surfaces (outer peripheries) of the photoconductor drums 32S, 32Y, 32M, 32C, and 32K, and cause toner supplied from a developing device (not shown) to adhere to the latent images, thereby forming toner images on the photoconductor drums 32S, 32Y, 32M, 32C, and 32K.

[0028] In the following description, when it is not necessary to distinguish between the image forming units 31S, 31Y, 31M, 31C, and 31K, they will be collectively referred to as image forming units 31. When it is not necessary to distinguish between the photoconductor drums 32S, 32Y, 32M, 32C, and 32K, they will be collectively referred to as photoconductor drum 32. When it is not necessary to distinguish between the developing units 33S, 33Y, 33M, 33C, and 33K, they will be collectively referred to as developing unit 33.

[0029] The image forming unit 30 also includes an intermediate transfer belt 34, a secondary transfer unit 35, and a fixing unit 36. The intermediate transfer belt 34 is a belt onto which the toner images formed on the photoconductor drums 32 of each color are primarily transferred, and rotates in a clockwise direction as indicated by a downward arrow in the figure. The secondary transfer unit 35 is a roller that secondarily transfers the toner images of each color primarily transferred onto the intermediate transfer belt 34 onto the paper Sh transported on the transport path 21.

[0030] The fixing unit 36 ​​is provided downstream of the secondary transfer unit 35 on the transport path 21, and performs a fixing process of fixing the toner image transferred to the paper Sh by the secondary transfer unit 335 onto the paper Sh. The fixing process of the toner image by the fixing unit 36 ​​is performed by pressing and heating the paper Sh onto which the toner image has been transferred with a roller (not shown). The paper Sh onto which the toner image has been fixed by the fixing unit 36 ​​is transported on the transport path 21 and discharged onto the paper output tray 40.

[0031] When double-sided printing is specified in the print job, the paper reversing unit 37 reverses the paper Sh and conveys it to the image forming unit 30 .

[0032] In the present embodiment, the image forming method of the image forming apparatus 1 is an electrophotographic method, but the present invention is not limited to this. The image forming method of the image forming apparatus 1 may be another method such as an inkjet method.

[0033] <Configuration of the control system of the image forming apparatus> Next, the configuration of a control system of the image forming apparatus 1 will be described with reference to Fig. 7. Fig. 7 is a block diagram showing an example of the configuration of the control system of the image forming apparatus 1.

[0034] As shown in FIG. 7, the image forming apparatus 1 includes a control unit 10, a communication unit 105, a document transport unit 11, a document reading unit 12, an operation display unit 13, an image forming unit 30, a paper feed unit 20, and a paper output tray 40.

[0035] The control unit 10 is a block that controls each component that constitutes the image forming apparatus 1, and includes a CPU (Central Processing Unit) 101, an HDD (Hard Disk Drive) 102, a memory 103, and a non-volatile memory 104. Each component that constitutes the image forming apparatus 1 is connected to each other via a bus so as to be able to communicate with each other.

[0036] CPU 101 executes various control programs and setting data stored in non-volatile memory 104 by loading the programs into memory 103. CPU 101 also controls the operation of each component connected via a bus. CPU 101 also provides a function of an image processing unit that analyzes the contents of a print job received from a terminal device (not shown) via communication unit 105 and generates image data for printing from document page data included in the print job.

[0037] Furthermore, CPU 101 expands on memory 103 and analyzes various information (job information Ij (see FIG. 8), page information Ip (see FIG. 9), image data information Id (see FIG. 10)) included in the print job sent from a terminal device (not shown). CPU 101 then determines whether an image in an area corresponding to the restricted area in the image data can be printed in the restricted area of ​​paper Sh. If CPU 101 determines that printing is possible, it does not erase the image, but causes image forming unit 30 to form all image data, including the image to be formed in the restricted area, on paper Sh.

[0038] The HDD 102 stores information about the processing functions of the image forming apparatus 1, read image data read by the document reading unit 12, print jobs received by the communication unit 105, etc. The HDD 102 may be configured with other storage media such as an SSD (Solid State Drive).

[0039] The memory 103 is composed of, for example, a RAM (Random Access Memory) and temporarily stores print jobs and various data. The memory 103 also provides a working memory space for the CPU 101. Image data processed by the CPU 101 is rasterized in the memory 103 and converted into bitmap data for each of the colors C, M, Y, K, and S for printing.

[0040] Non-volatile memory 104 is composed of, for example, a ROM (Read Only Memory), and stores programs and setting data for CPU 101 to control each component. Programs are stored in non-volatile memory 104 in the form of computer-readable program codes. Note that non-volatile memory 104 may be composed of a rewritable non-volatile memory such as an EEPROM (Electrically Erasable Programmable Read Only Memory) or a flash memory.

[0041] The program stored in the non-volatile memory 104 may be stored in the HDD 102. That is, the HDD 102 or the non-volatile memory 104 is used as an example of a computer-readable non-transitory recording medium that stores a program executed by a computer.

[0042] The communication unit 105 is connected to a network N via a LAN (Local Area Network) cable or the like (not shown), establishes a connection with a terminal device or the like (not shown), and controls the sending and receiving of data such as print jobs and various statuses between the device with which the connection has been established. The document transport section 11, the document reading section 12, the operation display section 13, the image forming section 30, the paper feed section 20 and the paper discharge tray 40 have already been described with reference to FIG. 6, and therefore description thereof will be omitted.

[0043] <First embodiment> Next, a first embodiment of the present invention will be described. Figure 8 is a diagram showing an example of job information Ij included in a print job transmitted from a terminal device not shown, Figure 9 is a diagram showing an example of page information Ip included in the print job, and Figure 10 is a diagram showing an example of image data information Id included in the print job.

[0044] [Job Info] 8, the job information Ij has the items "Toner Used," "Margin Position," and "Margin Size (mm)." The "Toner Used" item stores information on the color of the toner included in the image data, i.e., the toner color used when forming an image based on the image data.

[0045] In the item "Margin Position", information indicating the position of the margin on the sheet Sh, such as "leading edge" or "trailing edge", is stored. In the "Margin Size (mm)" item, information on the size of the margin, such as "6.0 (mm)" or "4.0 (mm)", is stored.

[0046] For example, the page information Ip shown in Fig. 8 indicates that an image consisting of five colors, C, M, Y, K, and S, can be formed in the area inside the margin up to 6.0 mm from the leading edge of the paper Sh in the paper feed direction. It also indicates that an image consisting of only S (spot color) can be formed in the area inside the margin up to 4.0 mm from the leading edge. In other words, it can be seen that only spot color images can be printed in the area 4.0 to 6.0 mm from the leading edge of the paper Sh.

[0047] [Page Info] As shown in FIG. 9, the page information Ip has the items "Parameter" and "Value." The "Parameter" item stores the names of various parameters defined in the page information Ip. The "Value" item stores the values ​​of various parameters. In the example shown in FIG. 9, the "Parameter" item stores the names of the parameters "Job ID," "Job type," "User name," "Job name," "Number of pages," "Number of copies," "Automatic inspection," "Staple," "Batch folding," and "Batch cutting."

[0048] The value of "Job ID" stores the job ID as an identifier assigned to each print job. The value of "Job type" stores the type of print job. "User name" stores the name (type) of the user who submitted the print job. The value of "Job name" stores the name of the print job. The value of "Number of pages" stores the number of pages contained in the print job. The value of "Number of copies" stores the number of copies to be printed.

[0049] The "automatic inspection" value is stored as an "on" or "off" value indicating whether automatic inspection is performed by an image inspection device, not shown. The "staple" value is stored as an "on" or "off" value indicating whether stapling post-processing is performed by a post-processing device, not shown. The "batch folding" value is stored as an "on" or "off" value indicating whether batch folding post-processing is performed by a post-processing device, not shown. The "batch cutting" value is stored as an "on" or "off" value indicating whether batch cutting post-processing is performed by a post-processing device, not shown.

[0050] 9 indicates that the job ID of the print job is “00001234”, the job type is “Print”, that is, printing, and the user name of the user who output the print job is “Operator”. The page information Ip also indicates that the job name of the print job is “Print Job 1”, the number of pages is “4”, and the number of copies to be printed is “1”.

[0051] Furthermore, the page information Ip indicates that the execution of automatic inspection is set to "off", and that the execution of post-processing such as "stapling", "collective folding", and "collective cutting" is also set to "off". Note that the page information Ip shown in Fig. 9 is an example, and the page information Ip may include items other than those shown in Fig. 9.

[0052] [Image data information] As shown in FIG. 10, the image data information Id has the items "Parameter" and "Value." The "Parameter" item stores the names of various parameters defined in the image data information Id. The "Value" item stores the values ​​of various parameters. In the example shown in FIG. 10, the "Parameter" item stores the names of the parameters "Job ID," "Page Number," "Paper Size," "Paper Type," "Basis Weight," "Paper Color," "Paper Tray," "Double-Sided," "Punch," and "Fold."

[0053] The value of "Job ID" stores the job ID of the print job. The value of "Page number" stores the page number assigned to each page included in the print job. The value of "Paper size" stores the paper size, such as "A4". The value of "Paper type" stores the type of paper Sh on which printing based on the print job will be performed. The value of "Basis weight" stores the basis weight (g / m 2 ) is stored.

[0054] The value of "paper color" stores the color of the paper Sh. The value of "paper feed tray" stores information about the paper feed tray into which the paper Sh to be printed is fed. The value of "double-sided" stores information about whether double-sided printing has been instructed ("double-sided") or single-sided printing has been instructed ("single-sided"). The value of "punch" stores a value of "on" or "off" indicating whether or not a post-processing device, not shown, will perform punching. The value of "fold" stores a value of "on" or "off" indicating whether or not a post-processing device, not shown, will perform folding.

[0055] In the image data information Id shown in FIG. 10, the size of the paper on which page number "1" of the print job with the job ID "00001234" is printed is "A4", the paper type is "plain paper", and the basis weight of the paper is "100 g / m 2" and the paper color is "black." The image data information Id also indicates that the paper feed tray into which the paper to be printed is fed is "feed tray 1" and that "single-sided printing" has been instructed. Furthermore, the image data information Id also indicates that the post-processing settings for both punching and folding are set to "off." Note that the image data information Id shown in FIG. 10 is just an example, and the image data information Id may include items other than those shown in FIG. 10.

[0056] Example 1 Next, an example of image processing according to Example 1 of the first embodiment of the present invention will be described. In Example 1, the area of ​​4.0 to 6.0 mm from the leading edge of the paper Sh in the paper feed direction is a restricted area Ar3 in which the formation of images in colors other than spot colors is restricted. The position and size of the restricted area Ar3, information on colors permitted to be printed in the restricted area SAr3, and the like are stored in the non-volatile memory 104 (see FIG. 7) of the image forming apparatus 1.

[0057] Furthermore, the paper Sh to be printed is an A4 (210 x 297 mm) sheet of paper that is completely black as shown in Figure 10, and the area in which the original image is formed using image data is an area of ​​202 x 289 mm excluding the 4.0 mm margins on the top, bottom, left, and right.

[0058] Fig. 11 is a diagram showing an example of image data P for each color according to Example 1 of the first embodiment. Fig. 11 shows image data P for each color of C, M, Y, K, and S, and an area PAr3 corresponding to restricted area Ar3 in the image data P. In Fig. 11, the area PAr3 is indicated by a dashed frame.

[0059] The control unit 10 (see FIG. 7) of the image forming apparatus 1 reads out information on the restricted area Ar3 when the image forming apparatus 1 is turned on (started up), etc. Then, the control unit 10 obtains information on the colors constituting the image to be printed in the restricted area SAr3 (see FIG. 5) from the image data P obtained by rasterizing the document page data included in the print job. The image to be printed in the restricted area Ar3 refers to the image of the part of the area PAr3 in the image data for each of the colors C, M, Y, K, and S shown in FIG.

[0060] The control unit 10 judges whether or not an image of the area PAr3 can be printed (image formed) in the restricted area Ar3. That is, it judges whether or not an image exists in the area PAr3 for each of the spot colors S, C, M, Y, and K. Then, when it is judged that only an image of the spot color S exists in the restricted area Ar3, the control unit 10 judges that the image of the area PAr3 can be formed in the restricted area Ar3, and causes the image forming unit 30 to form the image of the area PAr3 as it is without erasing it.

[0061] 12 is a flowchart showing an example of a process at the start-up of the image forming apparatus 1 according to the first embodiment. First, the control unit 10 of the image forming apparatus 1 judges whether the power of the image forming apparatus 1 is turned on or not (step S1). If it is judged in step S1 that the power is not turned on (if the judgment in step S1 is No), the control unit 10 repeats the judgment in step S1.

[0062] On the other hand, if it is determined in step S1 that the power is turned on (if the determination in step S1 is Yes), the control unit 10 reads out information on the restricted area stored in the non-volatile memory 104 or the like (step S2). After the process in step S2, the process at the start-up of the image forming apparatus 1 ends.

[0063] 13 is a flowchart showing an example of the procedure of image processing according to the embodiment 1. First, the control unit 10 of the image forming apparatus 1 judges whether or not a print job has been received from a terminal device (not shown) (step S11). If it is judged in step S11 that a print job has not been received (if the judgment in step S11 is No), the control unit 10 repeats the judgment in step S11.

[0064] On the other hand, if it is determined in step S11 that a print job has been received (if the determination in step S11 is Yes), the control unit 10 acquires image data by rasterizing the document page data included in the print job (step S12). Next, the control unit 10 compares the image data acquired in step S12 with the information on the restricted area acquired in step S2 of FIG. 12 (step S13).

[0065] Next, the control unit 10 judges whether or not an image can be formed in the restricted area (step S14). Since the restricted area SAr3 in FIG. 11 is an area where only images in spot colors can be printed, the control unit 10 judges whether or not the image included in this area is composed of only spot colors. In step S14, if it is judged that the image including the area PAr3 corresponding to the restricted area SAr3 includes colors other than spot colors, that is, that an image cannot be formed in the restricted area SAr3 (if the judgment in step S14 is No), the control unit 10 erases the image in the area PAr3 (step S15).

[0066] On the other hand, if it is determined in step S14 that image formation in the restricted area SAr3 is possible (if step S14 is determined as Yes), or after the processing of step S15, the control unit 10 forms an image of the image data on the paper Sh (step S16). In other words, if the control unit 10 determines in step S14 that image formation in the restricted area SAr3 is possible, the control unit 10 forms the image data as is on the paper Sh without performing image processing or the like on the image data.

[0067] According to the above-described first embodiment, the image data is printed on the paper Sh without reduction of the image data or erasure of unnecessary parts of the image.

[0068] Example 2 Next, image processing according to Example 2 of the first embodiment of the present invention will be described. In Example 2, the area of ​​4.0 to 6.0 mm from the leading edge of the paper Sh in the paper feed direction is a restricted area Ar3 in which formation of images other than those using only spot colors is restricted. The paper Sh to be printed is an A4 (210 x 297 mm) sheet of paper that is completely black as shown in Fig. 10, and the area in which the document image is formed using image data is an area of ​​202 x 289 mm excluding the 4.0 mm margins on the top, bottom, left, and right.

[0069] In the second embodiment, when an image to be formed in the restricted area SAr3 includes colors other than the spot colors, i.e., when the image cannot be formed in the restricted area SAr3, the control unit 10 of the image forming apparatus 1 determines whether the image to be formed in the restricted area SAr3 will include only the spot colors by rotating the image data up and down in the paper feed direction by 180°. If the control unit 10 determines that the image to be formed in the restricted area SAr3 will include only the spot colors by rotating the image by 180°, the control unit 10 forms the 180° rotated print image on the paper Sh without erasing the image.

[0070] FIG. 14 is a diagram showing an example of image data P for each color according to Example 2 of the first embodiment. FIG. 14 shows image data for each color of C, M, Y, K, and S, an area PAr3 corresponding to the restricted area Ar3 in the image data P, and an area PAr4 corresponding to the area PAr3 at the rear end of the paper Sh. In FIG. 14, the formation area of ​​an image including colors other than the spot color is shown by a dashed line frame, and the formation area of ​​an image consisting only of the spot color is shown by a dashed line frame. In the example shown in FIG. 14, an image consisting of five colors, C, M, Y, K, and S, exists in the area PAr3 at the leading edge of the paper, and only the spot color S exists in the area PAr4 at the rear end of the paper.

[0071] Fig. 15 is a diagram showing an example of a leading edge region PAr3 and a trailing edge region PAr4 in image data P formed by overlapping the colors shown in Fig. 14. In Fig. 15 as well, the formation region of an image including colors other than the spot colors is shown in a dashed line frame, and the formation region of an image consisting only of the spot colors is shown in a broken line frame. As shown in Fig. 15, the image in region PAr3 includes colors other than the spot colors, and the image in region PAr4 is consisting only of the spot colors.

[0072] 16 is a diagram showing image data P' in which the image in area PAr3 corresponding to restricted area SAr3 has been erased based on the conventional technology. It can be seen that the leading edge of the image data has been lost due to the image erasure process based on the conventional technology.

[0073] Fig. 17 is a diagram showing examples of images formed in the front end restricted area SAr3 and the rear end area SAr4 before and after rotating image data P by 180°. The upper part of Fig. 17 shows the image data P before rotation, and the lower part shows the image data Ph after rotation.

[0074] In the pre-rotation image data P shown in the upper part of Fig. 17, the image formed in the restriction area SAr3 contains colors other than the spot colors. On the other hand, in the post-rotation image data Ph shown in the lower part of Fig. 17, the image formed in the restriction area SAr3 contains only the spot colors.

[0075] Fig. 18 is a flowchart showing an example of the procedure of image processing according to the second embodiment. Steps S21 to S23 in Fig. 18 are the same as steps S11 to S13 in Fig. 13, and therefore the description will be omitted. The print job whose reception is confirmed in step S21 is the same as the print job in the first embodiment. That is, the print job includes the job information Ij shown in Fig. 8, the page information Ip shown in Fig. 9, and the image data information Id shown in Fig. 10.

[0076] In step S24, the control unit 10 judges whether or not image formation is possible in the restricted area SAr3. For example, in the example shown in Fig. 14, an image including not only the special color S but also C, M, Y, and K exists in the area PAr3 at the tip of the image data P. In this case, the judgment in step S24 is No.

[0077] If it is determined in step S24 that an image cannot be formed in the restricted area SAr3 (if step S24 is determined as No), the control unit 10 rotates the image data P by 180° (step S25). Next, the control unit 10 determines whether or not an image can be formed in the restricted area SAr3 with the rotated image data Ph (step S26).

[0078] In the rotated image data Ph shown in the lower part of Fig. 17, an image of a portion of the image data P before rotation in an area PAr41 at the rear end of the paper falls in an area PAr3 2 mm from the leading edge of the paper, but this portion of the image is composed only of the special color S. Therefore, image formation is possible, and the determination in step S26 is Yes. If it is determined in step S26 that image formation in the restricted area SAr3 is possible, the control unit 10 causes the image data Ph rotated 180° in step S25 to be formed on the paper Sh (step S29).

[0079] On the other hand, if it is determined in step S26 that image formation is not possible (if step S26 is determined as No), the control unit 10 rotates the image data Ph by -180 degrees to return it to the original image data P (step S27). Next, the image formed in the restricted area SAr3 is erased (step S28). After the process of step S28, the control unit 10 forms the image data P from which the image has been erased in step S28 on the paper Sh (step S29).

[0080] On the other hand, if it is determined in step S24 that image formation in the restricted area SAr3 is possible (if the determination in step S24 is Yes), the control unit 10 forms the image data as is on the paper Sh without performing image processing on the image data (step S29). After the processing in step S29, the image processing according to the second embodiment is completed.

[0081] According to the second embodiment, when an image can be formed in the restricted area SAr3 by rotating the image data P by 180 degrees, the image data Ph rotated by 180 degrees is formed on the paper Sh. In other words, according to the second embodiment, when an image formed in the restricted area SAr13 by rotating the image data P1 by 180 degrees becomes an image composed of only special colors, it becomes possible to perform printing that effectively utilizes the restricted area SAr3 without performing image reduction or unnecessary erasure.

[0082] Example 3 Next, image processing according to Example 3 of the first embodiment of the present invention will be described. In Example 3, the area of ​​4.0 to 6.0 mm from the leading edge of the paper Sh in the paper feed direction is a restricted area Ar3 in which formation of images other than those using only spot colors is restricted. The paper Sh to be printed is an A4 (210 x 297 mm) sheet of paper that is completely black as shown in Fig. 10, and the area in which the document image is formed using image data is an area of ​​202 x 289 mm excluding the 4.0 mm margins on the top, bottom, left, and right.

[0083] In the third embodiment, when an image to be formed in the restricted area SAr3 is an image that includes colors other than spot colors, the control unit 10 of the image forming apparatus 1 determines whether or not it is possible to form the image in the restricted area SAr3 by shifting the image data toward the leading edge or trailing edge of the paper Sh and expanding the area consisting of the image consisting of only the spot color. If it is determined that it is possible, the control unit 10 causes the image data, which has been subjected to the shifting of the image data toward the leading edge or trailing edge of the paper Sh and the expansion of the area consisting of the image consisting of only the spot color, to be formed on the paper Sh.

[0084] FIG. 19 is a diagram showing an example of image data P of each color according to Example 3 of the first embodiment. FIG. 19 shows image data P of each color of C, M, Y, K, and S, an area PAr3 corresponding to the restricted area Ar3 in the image data P, and an area PAr4 corresponding to the area PAr3 at the rear end of the paper Sh. In FIG. 19, the formation area of ​​an image including colors other than the spot color is shown by a dashed line frame, and the formation area of ​​an image consisting of only the spot color is shown by a dashed line frame. In the example shown in FIG. 19, in the area PAr3 at the front end of the paper, an image consisting of only the spot color exists in an area PAr31 within a range of 1 mm from the front end, and an image consisting of five colors, C, M, Y, K, and S exists in an area PAr41 1 mm from the rear end side in the area PAr4 at the rear end of the paper.

[0085] FIG. 20 is a diagram showing an example of an area PAr3 on the leading edge side and an area PAr4 on the trailing edge side in image data P formed by overlapping the colors shown in FIG. 19. In FIG. 20 as well, the formation area of ​​an image including colors other than the spot color is shown by a dashed line frame, and the formation area of ​​an image consisting of only the spot color is shown by a broken line frame. As shown in FIG. 20, an image consisting of only the spot color exists in an area PAr31 1 mm from the leading edge side, and an image consisting of five colors C, M, Y, K, and S exists in an area PAr32 of the following 1 mm. Also, an image consisting of only the spot color S exists in an area PAr41 1 mm from the trailing edge side of the area PAr4. In this case, in the third embodiment, the control unit 10 shifts the image data P 1 mm toward the trailing edge of the paper, and adds an image consisting of only the spot color to the area of ​​the leading edge portion after the shift. That is, the area consisting of only the image of the spot color is expanded in the direction of the leading edge of the paper.

[0086] Fig. 21 is a diagram showing an example of forming image data P before image shift and image data Ps after image shift on paper Sh. The upper part of Fig. 21 shows an example of forming image data P before image shift on paper Sh, and the lower part shows an example of forming image data Ps after image shift on paper Sh.

[0087] 21, an area PAr32, 1 mm wide, containing an image including colors other than spot colors exists within an area PAr3 corresponding to the restricted area SAr3. Meanwhile, at the rear end of the image data P, an area PAr41 (1 mm wide) exists within a range of 1 mm from the rear end, containing an image consisting only of spot colors.

[0088] In the image data Ps shown in the lower part of Fig. 21, the image data P shown in the upper part is shifted 1 mm toward the rear end, and an image using only spot colors is added to the first 1 mm area PAr31. The area PAr31 to which the image using only spot colors has been added is an area where no image has been removed due to the image shift. By performing such processing, it is possible to form the image data Ps on the paper Sh without causing any image loss.

[0089] Fig. 22 is a flowchart showing an example of the procedure of image processing according to the embodiment 3. Steps S31 to S33 in Fig. 22 are the same as steps S11 to S13 in Fig. 13, and therefore the description will be omitted. Note that the print job whose reception is confirmed in step S31 is the same as the print job in the embodiment 1, that is, the print job includes the job information Ij shown in Fig. 8, the page information Ip shown in Fig. 9, and the image data information Id shown in Fig. 10.

[0090] In step S34, the control unit 10 determines whether or not an image can be formed in the restricted area SAr3. In the example shown in FIG. 21, an image including not only the special color S but also C, M, Y, and K exists in the area PAr3 at the leading end of the image data P. In this case, the determination in step S34 is No. If it is determined in step S34 that an image cannot be formed in the restricted area SAr3 (if the determination in step S34 is No), the control unit 10 focuses on the image at the leading end in the image data P.

[0091] Then, the control unit 10 calculates the width (hereinafter also referred to as "width size") in the paper feed direction of the paper Sh of the area PAr3 corresponding to the restricted area SAr3 where an image other than the spot color exists, and inputs the calculated width size as the "necessary leading edge shift amount" (one example of the first size) into a predetermined area or the like of the memory 103 (see FIG. 6) (step S35). In the image data P shown in the upper part of FIG. 21, the width size of the area PAr31 where an image including a color other than the spot color exists is 1 mm, so in step S35, "1 mm" is input as the "necessary leading edge shift amount".

[0092] Next, the control unit 10 focuses on the image in the area corresponding to the rear end of the paper in the image data P, and determines whether or not there is an area in that area where an image consisting of only spot colors exists. If there is such an area, the control unit 10 calculates the width of the area at the rear end where the image consisting of only spot colors exists, and inputs the calculated width as the "possible rear end shift amount" (an example of the second size) (step S36).

[0093] In the image data P shown in the upper part of Fig. 21, the area PAr41 corresponding to the rear end of the paper is an area where an image consisting of only spot colors exists. And because the width size of this area PAr41 is 1.0 mm, in step S36, "1 mm" is input as the "possible rear end shift amount." Even if an image consisting of only spot colors is shifted outside the image forming range, the actual image including colors other than the spot colors is not lost, so it is considered that the image that constitutes this area can be shifted.

[0094] Next, the control unit 10 judges whether the "possible rear end shift amount" is equal to or larger than the "required front end shift amount" (step S37). If it is judged in step S37 that the "possible rear end shift amount" is equal to or larger than the "required front end shift amount" (if the judgement in step S37 is YES), the control unit 10 shifts the image data P toward the rear end by the width size input as the "required front end shift amount" (step S38).

[0095] Next, the control unit 10 adds an image (background image) consisting of only special colors to the region at the tip of the original position (step S39). If the "necessary tip shift amount" is 1 mm, the image shift amount is also 1 mm, so in step S39, the control unit 10 adds an image (background image) consisting of only special colors to the region of 1 mm at the tip of the image data.

[0096] On the other hand, if it is determined in step S37 that the "possible rear end shift amount" is less than the "required front end shift amount" (if step S37 is determined as No), the control unit 10 shifts the image data P toward the rear end by the width size input as the "possible rear end shift amount" (step S40). Next, the control unit 10 adds an image consisting of only special colors to the front end area from which the image is shifted (step S41).

[0097] After the process of step S39 or step S40, or if it is determined in step S34 that image formation in the restricted area is possible (if step S34 is determined as No), the control unit 10 causes the image forming unit 30 to form an image based on image data that is not subjected to any image processing, or image data that has been shifted toward the rear end and extended toward the front end to include only the special color (step S42). After the process of step S42, the image processing according to the third embodiment is completed.

[0098] According to the third embodiment, printing can be performed without causing loss of an image composed of colors other than the spot colors, and by making maximum use of the restricted area PAr3 in which formation of an image using only spot colors is permitted.

[0099] <Second embodiment> Next, a second embodiment of the present invention will be described. In the second embodiment, in a restricted area at the leading edge of a sheet set in the image forming apparatus 1 (see FIG. 6), formation of an image in four colors, C, M, Y, and K, is permitted, but formation of an image in five colors including a spot color is not permitted. The control unit 10 of the image forming apparatus 1 according to the second embodiment determines whether the image in the area corresponding to the restricted area will have four colors or less by rotating the image data 180° up and down, and if it will have four colors or less, forms an image based on the image data rotated 180° on the sheet Sh1.

[0100] Fig. 23 is a diagram showing an overview of a restricted area according to the second embodiment. The upper part of Fig. 23 shows an area SAr11 in which only an image of four colors, C, M, Y, and K, can be formed, the middle part shows an area SAr12 in which an image of five colors, S, C, M, Y, and K, can be formed, and the lower part shows an overlapping display of the area SAr11 and the area SAr12. The size of the paper Sh1 and the size of the area in which an image can be formed are the same as those of the paper Sh shown in Fig. 1.

[0101] As shown in the overlapping diagram of areas SAr11 and SAr12 in the lower part of Figure 23, the area ranging from 4.0 to 6.0 mm from the leading edge of the paper Sh in the paper feed direction Df is a restricted area SAr13 in which formation of an image composed only of special colors is permitted.

[0102] Fig. 24 is a diagram showing an example of job information Ij1, and Fig. 25 is a diagram showing an example of image data information Id1 included in a print job. It is assumed that the page information Ip included in the print job is the same as that shown in Fig. 9. The items included in the job information Ij1 shown in Fig. 24 are the same as those in the job information Ij shown in Fig. 8, and the items included in the image data information Id1 shown in Fig. 25 are the same as those in the image data information Id shown in Fig. 10.

[0103] The difference between job information Ij1 shown in FIG. 24 and job information Ij shown in FIG. 8 is that the information stored from the fifth line onwards in the “Toner Used” item is four colors (four colors out of CMYKS) rather than a spot color (S). 10. Also, the image data information Id1 shown in FIG. 25 differs from the image data information Id shown in FIG. 10 in that the paper color is "transparent" instead of "black."

[0104] Fig. 26 is a diagram showing an example of paper Sh1 on which image data according to the second embodiment is printed. The size of paper Sh1 is the same as that of paper Sh shown in Fig. 2 (A4 size: 210 x 297 mm), but the paper color is transparent. In other words, paper Sh1 is made of, for example, a transparent film.

[0105] Fig. 27 is a diagram showing an example of image data P1 formed on the paper Sh1 shown in Fig. 26. As shown in Fig. 26, the image data P1 is configured with a size of 202 x 289 mm excluding the 4.0 mm top, bottom, left and right margins. Then, five color images of C, M, Y, K and S exist in part of an area PAr13 2 mm from the leading edge corresponding to the leading edge of the paper, and four color images of C, M, Y and K exist in an area PAr14 2 mm from the trailing edge.

[0106] Fig. 28 is a diagram showing an example of image data P1 for each color. Fig. 28 shows image data for each color of C, M, Y, K, and S, a leading edge area PAr13, and a trailing edge area PAr14. In Fig. 28, the formation area of ​​an image including five colors is shown by a dashed line frame, and the formation area of ​​an image consisting of four colors is shown by a broken line frame. In the example shown in Fig. 28, an image consisting of five colors, C, M, Y, K, and S, exists in the area PAr13 at the leading edge of the paper, and an image consisting of four colors, C, M, Y, and K, exists in the area PAr14 at the trailing edge of the paper.

[0107] 29 is a diagram showing image data P1' in which the image of area PAr13 corresponding to restricted area SAr13 has been erased based on the conventional technology. It can be seen that the leading edge of image data P1 (leading edge of "A") has been lost due to the image erasure process based on the conventional technology.

[0108] Fig. 30 is a diagram showing examples of images formed in the front end side restricted area SAr13 and the rear end side area SAr14 before and after rotating the image data P1 by 180°. The upper part of Fig. 30 shows the image data P1 before rotation, and the lower part shows the image data P1h after rotation.

[0109] In the pre-rotation image data P1 shown in the upper part of Fig. 30, the image formed in the restricted area SAr13 is an image made up of five colors. On the other hand, in the rotated image data Ph1 shown in the lower part of Fig. 30, the image formed in the restricted area SAr13 is an image made up of four colors. In other words, with the rotated image data Ph1, it is possible to form the image on the paper Sh1 without erasing the portion of the image formed in the restricted area SAr13.

[0110] Fig. 31 is a flowchart showing an example of the procedure of image processing according to the second embodiment. Steps S51 to S53 in Fig. 31 are the same as steps S11 to S13 in Fig. 13, and therefore will not be described. Note that the print job whose reception is confirmed in step S51 is the same as that in the first embodiment, that is, the print job includes the job information Ij shown in Fig. 8, the page information Ip shown in Fig. 9, and the image data information Id shown in Fig. 10.

[0111] In step S54, the control unit 10 judges whether or not image formation is possible in the restricted area SAr13. For example, in the example shown in Fig. 28, an image including five colors C, M, Y, K, and S exists in the area PAr13 at the tip of the image data P1. In this case, the judgment in step S54 is No.

[0112] In step S54, if it is determined that an image cannot be formed in the restricted area SAr13 (if step S54 is determined as No), the control unit 10 rotates the image data P1 by 180° (step S25). Next, the control unit 10 determines whether or not an image can be formed in the restricted area SAr13 if the image data is Ph1 after the rotation (step S56).

[0113] In the rotated image data Ph1 shown in the lower part of Fig. 30, the image of the area PAr14 at the rear end of the paper in the unrotated image data P1 is included in the area PAr13 2 mm from the leading edge of the paper, but this image is composed of a four-color image. Therefore, image formation is possible, so the answer to step S56 is Yes.

[0114] If it is determined in step S56 that image formation in the restricted area SAr13 is possible (if step S56 is determined to be Yes), the control unit 10 causes the image data Ph1 rotated 180 degrees in step S55 to be formed on the paper Sh1 (step S59).

[0115] On the other hand, if it is determined in step S56 that image formation is not possible (if step S56 is determined as No), the control unit 10 rotates the image data Ph1 by -180 degrees to return it to the original image data P1 (step S57). Next, the control unit 10 erases the image formed in the restricted area SAr13 (step S58). After the process of step S58, the control unit 10 forms the image data P from which the image has been erased in step S58 on the paper Sh1 (step S59).

[0116] Furthermore, if it is determined in step S54 that image formation in the restricted area SAr13 is possible (if step S54 is determined as No), the control unit 10 forms the image data P1 as is on the paper Sh1 without performing image processing on the image data P1 (step S59). After the processing of step S59, the image processing according to the second embodiment is completed.

[0117] According to the second embodiment, when it becomes possible to form an image in the restricted area SAr13 by rotating the image data P by 180 degrees, the 180° rotated image data Ph1 is formed on the paper Sh1. In other words, according to the second embodiment, when the image formed in the restricted area SAr13 by rotating the image data P1 by 180 degrees becomes an image consisting of only four colors, it becomes possible to perform printing that effectively utilizes the restricted area SAr13 without performing image reduction, unnecessary erasure, etc.

[0118] In the above-described embodiments, the image data on which the control unit 10 of the image forming apparatus 1 performs the image processing according to the present invention is image data obtained by rasterizing document page data included in a print job, but the present invention is not limited to this. The image data on which the image processing according to the present invention is performed may be read data read by the document reading unit 12 (see FIG. 6).

[0119] Furthermore, the present invention is not limited to the above-described embodiment, and it goes without saying that various other applications and modifications are possible without departing from the gist of the present invention as set forth in the claims. For example, the above-described embodiment describes the configuration of the device in detail and specifically in order to clearly explain the present invention, and is not necessarily limited to having all of the configurations described.

[0120] In addition, the control lines and information lines shown by solid lines or arrows in Figure 7 are those that are considered necessary for explanation, and do not necessarily show all the control lines and information lines in the product. In reality, it can be considered that almost all components are connected to each other. [Explanation of symbols]

[0121] 1: image forming apparatus, 10: control unit, 30: image forming unit, Id: image data information, Ij: job information, Ip: page information, SAr3: restricted area

Claims

1. and a control unit that acquires information on colors constituting an image formed in a restricted area in which the colors or the number of the colors are restricted from image data of an image formed on a recording material, and when it is determined that the colors or the number of colors are permitted for image formation in the restricted area, causes the image forming unit to form the image data including the image formed in the restricted area. Image forming device.

2. When the control unit determines that the colors or the number of colors constituting the image formed in the restricted area are not permitted for image formation in the restricted area, and determines that the colors or the number of colors constituting the image formed in the restricted area will become permitted for image formation in the restricted area by shifting the image data toward the rear end in the paper feed direction of the recording material, the control unit causes the image forming unit to form the shifted image data. The image forming apparatus according to claim 1 .

3. The control unit calculates a first size, which is a width size in the paper feed direction of the recording material, in which an image formed in the restricted area includes the number of colors or the number of colors permitted for image formation in the restricted area, and a second size, which is a width size in the paper feed direction of the recording material, in which an image exists in the rear end of the image data and includes the number of colors or the number of colors permitted for image formation in the restricted area, and if the second size is equal to or larger than the first size, shifts the image data by the first size toward the rear end in the paper feed direction of the recording material. The image forming apparatus according to claim 2 .

4. When the second size is smaller than the first size, the control unit shifts the image data by the second size toward a rear end of the recording material in a paper passing direction. The image forming apparatus according to claim 3 .

5. When the control unit determines that the colors or the number of colors constituting the image formed in the restricted area are not permitted for image formation in the restricted area, and determines that the colors or the number of colors constituting the image formed in the restricted area will become permitted for image formation in the restricted area by rotating the image data up and down in the paper feed direction of the recording material, the control unit causes the image forming unit to form the image data rotated up and down. The image forming apparatus according to claim 1 .

6. The color permitted for image formation in the restricted area is a special color. The image forming apparatus according to any one of claims 1 to 5.

7. The number of colors permitted for image formation in the restricted area is the number of colors not including spot colors, and the number of colors not permitted for image formation in the restricted area is the number of colors including spot colors. The image forming apparatus according to any one of claims 1 to 5.

8. The method includes a step of acquiring information on colors constituting an image formed in a restricted area in which the colors or the number of the colors are restricted from image data of an image formed on a recording material, and when it is determined that the colors or the number of colors are permitted for image formation in the restricted area, causing an image forming unit to form the image data including the image formed in the restricted area. Image processing methods.

Images