JP6635335B2 - Image inspection device and image forming system - Google Patents

Description

  The present invention relates to an image inspection device and an image forming system.

  2. Description of the Related Art Conventionally, there has been known an image inspection apparatus that inspects an original image formed on a recording material such as a sheet by an image forming apparatus based on original information.

  For example, Patent Document 1 discloses scan image data (inspection target image data) and reference image data (reference image data) obtained by reading a print image on a printed material printed based on print image data (original information) with a scanner. And an image inspection apparatus that inspects a printed image by comparing the two. In this image inspection apparatus, the cause of the inspection result of NG in the scanned print image is partially enlarged and displayed. The user visually checks the cause of the enlarged and displayed print image and checks the inspection result by the image inspection device.

  In this image inspection apparatus, when inspecting a print image (integrated image) in which a dot pattern (additional information image) indicating information or the like (additional information) for specifying a printing device is superimposed on an original image (document image) Also, the user visually checks the cause of the enlarged printed image to check the inspection result. This dot pattern is a small-sized image that is difficult for the user to see on the printed matter, but is easily recognized by the user in the enlarged display state, and the dot pattern is erroneously assumed to be toner scattering or the like. May be recognized. In the image inspection apparatus disclosed in Patent Document 1, when the dot pattern is included in a cause portion of a print image to be enlarged and displayed, a process of thinning out the dot pattern is performed, and the cause portion of the print image to be enlarged and displayed is Display control is performed so that the dot pattern is not displayed.

  In a conventional image inspection apparatus, when an image on a recording material is inspected by comparing image data to be inspected obtained from an image formed on the recording material with reference image data, an image is added to the image on the recording material. Even if the information image was included, the influence on the inspection result was small. However, in recent years, there have been many situations where higher quality images are required, and more detailed image inspection has become necessary. The influence of the additional information image included in the image is increasing.

In order to solve the above-described problem, the present invention provides, as inspection target image data, image data of a recording material on which a document image based on document information and an additional information image based on additional information not included in the document information are formed. Inspection target image data obtaining means, reference image data generation means for generating reference image data, and inspecting an image on the recording material using a result of comparing the inspection target image data with the reference image data. An image inspection apparatus having an image inspection process executing unit that executes an image inspection process , wherein a plurality of pixels corresponding to the dot size of the additional information image are added to the inspection object image data acquired by the inspection image data acquisition unit. and shifted by one pixel pixel block of, and identify the position of a pixel block including said additional information image, said from the inspection object image data Has an additional information image removing means for removing the additional information image data component corresponding to the pressure information image, before Symbol image inspection processing execution means, inspection after removal of the additional information image data by the additional information image removing means The image inspection process is performed using a result obtained by comparing target image data with the reference image data.

  Advantageous Effects of Invention According to the present invention, there is an excellent effect that an additional information image included in an image on a recording material can reduce the influence on an image inspection.

FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming system according to a first embodiment. FIG. 2 is a control block diagram of a printer and an image inspection device that constitute the image forming system. FIG. 3 is a control block diagram when writing data is generated in an image generation control unit of the printer. It is a control block diagram of a master image generation part in the same image inspection device. 9 is a flowchart illustrating a flow of an image inspection process for inspecting a print image on a printed material printed by the printer. It is a flowchart which shows the flow of the additional pattern removal process performed by the additional pattern removal part in the same image inspection apparatus. FIG. 14 is an explanatory diagram of a modification in which it is determined whether or not a dot forms an additional pattern in units of a block including a plurality of pixels. 15 is a flowchart illustrating a flow of an additional pattern removing process according to a modification. FIG. 9 is a control block diagram of a printer and an image inspection device according to a second embodiment. 9 is a flowchart illustrating a flow of an image inspection process according to the second embodiment. 13 is a flowchart illustrating a flow of an additional pattern adding process according to the second embodiment. FIG. 13 is a control block diagram of a printer and an image inspection device according to a third embodiment. 13 is a flowchart illustrating a flow of an image inspection process according to the third embodiment.

[Embodiment 1]
Hereinafter, an embodiment in which the present invention is applied to an image forming system including an electrophotographic image forming apparatus and an image inspection apparatus that inspects an image formed on a recording material by the image forming apparatus (hereinafter, referred to as an image forming system). This embodiment is referred to as “Embodiment 1”).
Note that the image inspection apparatus according to the present invention may be configured separately from the image forming apparatus.

FIG. 1 is a schematic diagram illustrating an overall configuration of an image forming system 1 according to the first embodiment.
As shown in FIG. 1, the image forming system 1 according to the first embodiment includes a printer 110 as an image forming apparatus, an operation unit 120 as an operation receiving unit that receives a user operation, a paper feeding unit 130, and an image inspection device 140. And a stacker 150. According to the input print job, the image forming system 1 forms (prints) an image on a sheet as a recording material in the printer 110 based on the document information related to the print job, and the image inspection apparatus 140 Inspect the printed image on (printed).

  The printer 110 has four photoconductors 113K, 113C, 113M, and 113Y as latent image carriers on which black (K), cyan (C), magenta (M), and yellow (Y) toner images are respectively formed. ing. Above the photoconductors 113K, 113C, 113M, and 113Y, an optical writing device 115 as a latent image forming unit that irradiates writing light for forming an electrostatic latent image on the surface of each photoconductor is arranged. Have been. Around the photoconductors 113K, 113C, 113M, and 113Y, a charging device as charging means for uniformly charging the photoconductor surface to a desired charging potential, and writing light of each color emitted from the optical writing device 115 is used. A developing device for developing the formed electrostatic latent image with a developer, a primary transfer device as a primary transfer unit for transferring a toner image formed on the photoconductor by development onto an intermediate transfer belt 111 as an intermediate transfer member, A cleaning device or the like is disposed as cleaning means for removing toner remaining on the surface of the photoconductor after transfer.

  Each of the photoconductors 113K, 113C, 113M, 113Y and the intermediate transfer belt 111 are driven to rotate in a direction to rotate with each other, and the surfaces of the photoconductors 113K, 113C, 113M, 113Y are set to a desired charging potential by respective charging devices. Charged. The optical writing device 115 applies black (K), cyan (C), and magenta (M) generated on the uniformly charged surfaces of the photoconductors 113K, 113C, 113M, and 113Y based on the document information related to the print job. M) and write light based on the write data for each color of yellow (Y). Thus, an electrostatic latent image corresponding to each color is formed on the surface of each of the photoconductors 113K, 113C, 113M, and 113Y. Thereafter, the electrostatic latent images of the respective colors are subjected to development processing by developers of the respective colors by respective developing devices, whereby the toners of the respective colors adhere to the respective electrostatic latent images of the respective colors, and the respective colors are formed on the surfaces of the respective photoconductors. Is formed.

  The respective color toner images formed on the photoconductors 113K, 113C, 113M, and 113Y in this manner are primary-transferred to the surface of the intermediate transfer belt 111 by the respective primary transfer devices so as to overlap each other. As a result, on the surface of the intermediate transfer belt 111, a color toner image in which the color toner images overlap is formed. This color toner image is conveyed to a secondary transfer area facing the secondary transfer roller 116 as the intermediate transfer belt 111 rotates. In this secondary transfer area, the secondary transfer roller 116 contacts the part of the intermediate transfer belt 111 wound around the secondary transfer opposing roller 112 to form a secondary transfer nip. The paper fed from the paper feed unit 130 is fed into the secondary transfer nip by the registration roller pair 117 at the timing when the color toner image on the intermediate transfer belt 111 reaches the secondary transfer nip. Then, in the secondary transfer nip, the color toner image on the intermediate transfer belt 111 is secondarily transferred onto the sheet.

  The sheet on which the color toner image has been secondarily transferred is sent to the fixing device 114, where the color toner image is fixed on the sheet. The paper (printed matter) on which the color toner image is formed in this manner is directly conveyed to the image inspection device 140 in the case of single-sided printing. On the other hand, in the case of double-sided printing, the sheet is reversed in a reversing pass, the sheet is again conveyed to the secondary transfer nip, and the color toner image is secondarily transferred also to the opposite side, and is transferred to the fixing device 114. After fixing, the sheet is conveyed to the image inspection apparatus 140.

  The operation unit 120 is an output interface that visually displays the state of the image forming system 1, and is used as a touch panel when a user directly operates the image forming system 1 or inputs information to the image forming system 1. It is also an input interface. That is, the operation unit 120 includes a function of displaying an image for receiving an operation by the user.

  The paper feed unit 130 stores a large number of papers before image formation, feeds the papers one by one, and sends them out to the registration roller pair 117.

  The image inspection apparatus 140 includes a first scanner 141 as an inspection target image data acquisition unit that reads an image formed on one surface (upper surface in FIG. 1) of a printed sheet (printed material) conveyed from the printer 110. And a second scanner 142 as an inspection target image data acquisition unit that reads an image formed on the other surface (the lower surface in FIG. 1) of the printed matter. The first scanner 141 and the second scanner 142 are installed so as to face each other with the printed material transport path 143 interposed therebetween, and when the printed material is transported through the printed material transport path 143, the images on both sides of the printed material are printed. The data can be read at once by the first scanner 141 and the second scanner 142. In the image inspection apparatus 140, as described later, image data of a print image on a printed material read by the first scanner 141 and the second scanner 142 (hereinafter, referred to as “scan image data”), and a master image as reference image data By comparing the data with the data, the quality of the print image formed on the print is inspected. The printed material read by the first scanner 141 and the second scanner 142 proceeds on the printed material transport path 143 and is transported to the stacker 150 as it is.

  The stacker 150 stacks the printed materials conveyed from the image inspection device 140 on the tray 151.

FIG. 2 is a control block diagram of the printer 110 and the image inspection device 140 according to the first embodiment.
In the image forming system 1, in a RIP (Raster Image Processor) 201 of the printer 110, PDL (Page Description Language) such as PostScript, image information such as TIFF (Tagged Image File Format) and image information (external information from a storage medium) such as TIFF (Tagged Image File Format) are received. Or from an external device via a communication network. The RIP 201 generates a CMYK raster image (RIP image) of cyan (C), magenta (M), yellow (Y), and black (K) based on the received document information. The generated RIP image data is sent to a printer control unit 202 that controls the entire printer 110, and is transferred from the printer control unit 202 to an image generation control unit 203 that controls an image forming operation. Will also be forwarded.

FIG. 3 is a control block diagram when the image generation control unit 203 of the printer 110 generates write data.
The image generation control unit 203 converts the CMYK RIP image data transferred from the printer control unit 202 into cyan (C), magenta (M), yellow (Y), and black (K) in the color separation processing unit 203A. Decompose into image data of each color. Then, as for the C image data, the C writing data generation unit 203B generates C writing data for irradiating the C writing light from the optical writing device 115. Similarly, for the M image data, the M writing data generation unit 203C generates M writing data for irradiating the M writing light from the optical writing device 115. Similarly, for the K image data, the K writing data generation unit 203D generates K writing data for irradiating the K writing light from the optical writing device 115. Similarly, in the Y image data, the Y writing data generation unit 203F generates Y writing data for irradiating the Y writing light from the optical writing device 115. Then, the image generation control unit 203 controls the optical writing device 115 based on the generated writing data of each color, and irradiates the surface of each of the photoconductors 113K, 113C, 113M, 113Y with writing light of each color. .

  Here, in the first embodiment, the image generation control unit 203 converts the data of an additional pattern (additional information image) indicating additional information such as printer identification information for identifying the printer 110 into RIP image data based on the document information. To be added. Specifically, the additional pattern addition processing unit 203E of the image generation control unit 203 adds the image data of the additional pattern (additional information image) to the Y image data after the color separation by the color separation processing unit 203A. I do. Here, the additional pattern image data is added to the Y image data so that the yellow (Y) additional pattern, which is difficult for the user to see, is printed. May be added. Further, image data of an additional pattern may be added to image data of two or more colors.

  In the first embodiment, a print image in which a document image based on document information and an additional pattern based on additional information are integrated is formed on a printed material. The additional pattern is formed by a dot pattern obtained by encoding or encoding additional information, and is formed in a predetermined small area (pattern area) on a sheet in a small size that is difficult for a user to visually recognize. . It is sufficient that the user does not visually recognize the dot pattern. For example, the dot pattern may be distributed over the entire original image.

FIG. 4 is a control block diagram of the master image generation unit 211 in the image inspection device 140.
The image inspection apparatus 140 receives the RIP image data transferred from the printer control unit 202 at the master image generation unit 211 as a reference image data generation unit. In the master image generation unit 211, first, RIP image data of the CMYK system is converted into multi-valued bits in the small-value / multi-value conversion processing unit 211A. After that, in the resolution conversion processing unit 211B, resolution conversion is performed so as to have the same resolution as the scan image data (inspection target image data) read by the first scanner 141 and the second scanner 142 of the image inspection device 140. Then, the color conversion processing unit 211C performs a color conversion process of performing color conversion from the CMYK method to the same RGB method as the scan image data. Through these processes, master image data (reference image data) in the same format as the scan image data is generated from the CMYK RIP image data. The master image data generated in this way is output from the master image generation unit 211 and stored in the buffer 212.

FIG. 5 is a flowchart illustrating a flow of an image inspection process for inspecting a print image on a printed material printed by the printer 110.
The image inspection processing performed in the first embodiment is for inspecting the print quality of a printed matter, and is mainly for inspecting the image quality of a printed image. Includes those that inspect for distortion, or broken edges of printed matter.

  When a print job is input to the printer control unit 202 of the printer 110 (S1), the printer control unit 202 controls the image generation control unit 203 according to the input print job, and based on document information related to the print job. An image is formed (printed) (S2). At this time, as described above, the image generation control unit 203 adds the image data of the Y additional pattern to the document image data based on the document information, and places the document image based on the document information and the additional pattern on the paper. Is formed (printed).

  On the other hand, the image inspection apparatus 140 acquires document information from the printer control unit 202 (S3), and the master image generation unit 211 generates a master image from the document information (S4). On the other hand, the printed matter on which the print image is formed on the paper in the printer 110 is sent to the image inspection device 140 and, as shown in FIG. 2, a print image reading unit 213 constituted by the first scanner 141 and the second scanner 142. To read the print image on the print (S5). The scanned image thus obtained is sent to an additional pattern removing unit 215 as additional information image removing means in the image inspection device 140, as shown in FIG. Then, the additional pattern removing unit 215 performs an additional pattern removing process for removing an additional pattern included in the scanned image, as described later.

  The scan image data from which the additional pattern has been removed by the additional pattern removal unit 215 in this manner is sent to the comparison inspection unit 214 as an image inspection processing execution unit in the image inspection device 140 as shown in FIG. Upon acquiring the scan image data, the comparison inspection unit 214 acquires master image data from the buffer 212. Then, an image inspection process for inspecting a print image on a printed material is executed using the result of comparison between the scanned image data and the master image data (S7).

  In the image inspection process according to the first embodiment, for example, for each predetermined image range (for example, 9 × 9 pixels), a difference in pixel value between the scan image data and the master image data is obtained, and the difference value is set to a predetermined value. When the value is equal to or larger than the threshold value, it is determined that an image quality abnormality (such as background smear, toner loss, white spots, or streaks) has occurred in the image range. The content of the image inspection processing is not particularly limited as long as the scanned image data is compared with the master image data to inspect the print image.

  After completing the image inspection process on the entire print image of the printed matter, the comparison inspection unit 214 of the image inspection device 140 outputs the inspection result to the printer control unit 202 of the printer 110 (S8). Accordingly, if the inspection result indicates that an image quality abnormality has occurred, the printer control unit 202 reprints the print image of the print, stops the printing operation of the image forming system 1, and warns the operation unit 120. A predetermined abnormal process such as display is executed.

  The above processing is executed for each printed material until the print job is completed (S9). In the first embodiment, the image inspection process is performed on all the printed materials, but the image inspection process is not necessarily performed on all the printed materials, such as performing the image inspection process on a predetermined number of printed materials.

FIG. 6 is a flowchart illustrating the flow of the additional pattern removal process performed by the additional pattern removal unit 215.
In the first embodiment, when the additional pattern removing unit 215 obtains a scan image from the print image reading unit 213 (S11), first, the additional pattern removing unit 215 applies the pattern to a predetermined pattern area on a printed material on which the additional pattern is formed. It is determined whether or not the region is a background portion (S12). That is, if the pattern area is a non-original image area where no original image based on the original information is present, it is determined to be a background portion, and if the pattern area is an original image area where an original image based on the original information is present. It is determined that it is not the background portion. This determination can be made from the position of the pattern area on the paper and the pixel position of the document image obtained from the document information.

  When it is determined that the pattern area is the background part (Yes in S12), the additional pattern removing unit 215 reads the first pixel value in the pattern area from the scan image data (S13). Then, it is determined whether or not the pixel value is a pixel value of a dot forming the additional pattern, that is, a pixel value (Y value) of yellow (Y) (S14).

Specifically, for example, the R value of the pixel is larger than a predetermined R threshold, and the G value of the pixel is larger than a predetermined G threshold, and the B value of the pixel is larger than a predetermined B threshold. If is also smaller, it is determined that the pixel value of the pixel is the Y value.
Or, when the R value of the pixel is within a predetermined R numerical value range, the G value of the pixel is within a predetermined G numerical value range, and the B value of the pixel is smaller than a predetermined B threshold value , The pixel value of the pixel is determined to be the Y value.

  When determining that the pixel value is the Y value (Yes in S14), the additional pattern removing unit 215 converts the pixel value into a pixel value indicating the color of the background portion (S15). Normally, the background portion is white, so in the first embodiment, the R value, G value, and B value of the pixel are converted into values corresponding to white, respectively. However, when the background portion is other than white, it may be converted to a color other than white, such as by converting to a pixel value corresponding to a color specified by a user's instruction. On the other hand, when determining that the pixel value is not the Y value (No in S14), the additional pattern removing unit 215 does not convert the pixel value and maintains the original pixel value.

  The above processing steps S13 to S15 are sequentially performed on the pixel values in the pattern area read in a predetermined order (raster order) (S16), and when the processing is completed for all the pixel values in the pattern area, the additional pattern is removed. The process ends.

  According to the first embodiment, neither the master image data nor the scan image data to be compared with each other in the image inspection processing of the comparison inspection unit 214 includes the image data of the additional pattern. Therefore, in comparison with the case where only one of the additional patterns is included, an erroneous inspection result due to the additional pattern in the comparative inspection (image inspection) can be avoided, and an appropriate image inspection result can be obtained. be able to.

  In the processing step S12, when it is determined that the pattern area is not the background portion (No in S12), the additional pattern removal processing is terminated for the scan image data without removing the additional pattern in the pattern area. I do.

  When a document image exists in the pattern area, the pixels (pixels on the print image) on which the dots forming the additional pattern are formed are replaced with the color (Y) of the additional pattern from the color (pixel value) of the document image. ing. In this case, if the additional pattern removal processing is performed by performing the above-described processing steps S13 to S16, the pixel values (Y values) of the pixels forming the additional pattern are replaced with white pixel values. As a result, in comparison with the case where the pixel value (Y value) of the pixel forming the additional pattern is not replaced, an incorrect inspection result of an abnormal image (white spot) may be output in the subsequent image inspection processing. .

  If the pixel value of the original image in the pattern area is a pixel value of yellow (Y), the above-described processing steps S13 to S16 are performed to perform the additional pattern removal processing. However, there is a possibility that this is erroneously determined to be a pixel of the additional pattern. In this case, the pixel value of the original image in the pattern area is replaced, and an incorrect inspection result of an abnormal image may be output in the subsequent image inspection processing.

According to the first embodiment, when it is determined that the pattern area is not the background portion, the additional pattern removal processing ends, so that a situation in which an erroneous inspection result is output as described above can be suppressed.
Of course, the additional pattern removal processing may be performed even if the pattern area is not a background portion, as long as the situation where the above-described erroneous inspection result is output can be suppressed by another method. For example, when the pattern area is not the background portion, the pixel value (Y value) of the pixel forming the additional pattern is replaced with the average value of the surrounding pixel values instead of the white pixel value. A situation in which an incorrect inspection result is output can be suppressed as compared with the case where the pixel value is replaced with a white pixel value.

(Modification)
Next, a modification of the additional pattern removing process according to the first embodiment will be described.
In the first embodiment described above, it is determined whether or not the dots constitute the additional pattern for each pixel of the scan image data. However, in this modification, as shown in FIG. It is determined whether or not the dots constitute the additional pattern in a block unit (4 × 4 pixels) of a corresponding plurality of pixels.

FIG. 8 is a flowchart showing the flow of the additional pattern removal process in this modification.
Also in this modified example, similar to the first embodiment, when it is determined that the pattern area is the background portion (Yes in S12), the additional pattern removal processing is performed. However, in the additional pattern removal processing of this modification, the pixel value of the first block (4 × 4 pixels) in the pattern area is read from the scan image data (S13 ′). Then, it is determined whether or not the block includes dots of the additional pattern (S14 ').

  Specifically, for example, it is determined whether or not each pixel value is a pixel value of a dot forming the additional pattern, that is, a pixel value (Y value) of yellow (Y) for all pixel values in the block. Then, the ratio of the number of pixels determined to be the Y value to the total number of pixels in the block is calculated, and if the ratio is within a predetermined range, the block includes dots of the additional pattern. Judge to include. Note that this determination method is an example, and another determination method may be used.

  When it is determined that the block includes the dot of the additional pattern (Yes in S14 ′), the additional pattern removing unit 215 replaces all the pixel values in the block with the pixel value indicating the color of the background portion (here, the white pixel value). Value) (S15 '). On the other hand, when it is determined that the block does not include the dot of the additional pattern (No in S14 '), the additional pattern removing unit 215 does not perform the pixel value conversion for all the pixel values in the block, Maintain the original pixel values.

  The above processing steps S13 'to S15' are sequentially performed while shifting the position of the block by one pixel (S16), and when the processing has been completed for all the blocks in the pattern area, the additional pattern removal processing ends.

  As in the first embodiment described above, when it is determined whether or not each pixel of the scan image data is a dot of the additional pattern, for example, for a pixel in which the dot of the additional pattern is formed only in a part of the pixel, the additional pattern is used. It is difficult to properly judge that the dots are dots. In that case, the pixel value of the pixel which is the dot of the additional pattern cannot be converted to the pixel value of the background portion, and the removal of the additional pattern may occur. On the other hand, when it is determined whether or not a dot is an additional pattern in block units as in the present modification, such pixels can be appropriately determined, and the additional pattern is less likely to be left unremoved.

[Embodiment 2]
Next, another embodiment (hereinafter, this embodiment is referred to as “second embodiment”) in which the present invention is applied to an image forming system as in the above-described first embodiment will be described.
The image forming system according to the second embodiment is almost the same as the first embodiment except that the image inspection process in the image inspection apparatus 140 is different. This will be mainly described.

FIG. 9 is a control block diagram of the printer 110 and the image inspection device 140 according to the second embodiment.
FIG. 10 is a flowchart illustrating the flow of the image inspection process according to the second embodiment.
When a print job is input to the printer control unit 202 of the printer 110 (S21), the printer control unit 202 controls the image generation control unit 203 according to the input print job, and performs the printing, as in the first embodiment. An image is formed (printed) based on the document information relating to the job (S22). At this time, similarly to the first embodiment, the image generation control unit 203 adds the image data of the Y additional pattern to the document image data based on the document information, and places the document image based on the document information on the paper. A printed image in which the and the additional pattern are integrated is formed (printed).

  In the second embodiment, the image inspection apparatus 140 acquires document information from the printer control unit 202 (S23), and causes the master image generation unit 211 to generate a master image from the document information (S24). The master image generated in this manner is sent to the additional pattern adding unit 216 in the image inspection device 140, as shown in FIG. Then, the additional pattern adding unit 216 performs an additional pattern adding process of adding an additional pattern to the master image, as described later (S25).

  On the other hand, the printed matter having the print image formed on the paper in the printer 110 is sent to the image inspection device 140, and the print image on the printed matter is read by the print image reading unit 213 as in the first embodiment (S26). . The scan image thus obtained is sent to the comparison inspection unit 214 of the image inspection device 140, as shown in FIG. Upon acquiring the scan image data, the comparison inspection unit 214 acquires, from the buffer 212, master image data to which the additional pattern has been added. Then, an image inspection process for inspecting a print image on a printed material is performed using the result of comparison between the scanned image data and the master image data (S27). Note that the image inspection processing in the second embodiment is the same as that in the first embodiment.

FIG. 11 is a flowchart illustrating the flow of the additional pattern adding process performed by the additional pattern adding unit 216.
In the second embodiment, when the additional pattern adding unit 216 acquires the master image (no additional pattern) from the master image generating unit 211 (S31), the image forming control unit 203 of the printer 110 outputs dots forming the additional pattern. Information on the pixel position to be formed is obtained (S32). Thereafter, the additional pattern adding unit 216 reads out the first pixel value in a predetermined pattern area on the printed material on which the additional pattern is formed (S33). Then, based on the obtained pixel position information of the additional pattern, it is determined whether or not the position of the pixel value is a pixel position where a dot of the additional pattern is formed (S34).

  When it is determined that the position of the pixel value is the pixel position where the dot of the additional pattern is formed (Yes in S34), the additional pattern adding unit 216 sets the pixel value to the same color (Y) as the dot of the additional pattern. (S35). On the other hand, when it is determined that the position of the pixel value is not the pixel position where the dot of the additional pattern is formed (No in S34), the additional pattern adding unit 216 does not convert the pixel value and returns the original pixel value. Keep it as it is.

  The above processing steps S33 to S35 are sequentially performed on the pixel values in the pattern area read in a predetermined order (raster order) (S36), and when the processing is completed for all the pixel values in the pattern area, the additional pattern is added. The process ends.

  According to the second embodiment, the image data of the same additional pattern is included in both the master image data and the scanned image data that are compared with each other in the image inspection processing of the comparison inspection unit 214. Therefore, in comparison with the case where only one of the additional patterns is included, an erroneous inspection result due to the additional pattern in the comparative inspection (image inspection) can be avoided, and an appropriate image inspection result can be obtained. be able to.

Here, in the process of removing the additional pattern from the scan image as in the first embodiment, the pixel value (Y value) of the pixel forming the additional pattern in the scan image is replaced with another pixel value. In this case, it is difficult to replace the original image with the same pixel value. Therefore, even if it is possible to avoid a situation in which an erroneous inspection result due to the additional pattern is output, an erroneous inspection result may be output due to replacement of pixel values.
In the process of removing an additional pattern from a scanned image as in the first embodiment, there is a possibility that a pixel that does not form the additional pattern as described above may be erroneously determined to be a pixel of the additional pattern. . In this case, the pixel value of the original image in the pattern area is replaced, and there is a possibility that an erroneous inspection result may be obtained due to the replacement of the pixel value.

  On the other hand, in the process of adding the additional pattern to the master image as in the second embodiment, the pixel position and the color (pixel value) of the additional pattern can be grasped in advance, so that the pixel value of the master image is replaced. However, this does not cause a situation in which an incorrect test result is obtained. In this regard, the second embodiment is more advantageous than the first embodiment.

[Embodiment 3]
Next, a description will be given of still another embodiment (hereinafter, this embodiment is referred to as “third embodiment”) in which the present invention is applied to an image forming system, similarly to the first and second embodiments.
The image forming system according to the third embodiment is substantially the same as the second embodiment except that the image inspection process in the image inspection apparatus 140 is different. This will be mainly described.

FIG. 12 is a control block diagram of the printer 110 and the image inspection device 140 according to the third embodiment.
FIG. 13 is a flowchart illustrating the flow of the image inspection process according to the third embodiment.
When a print job is input to the printer control unit 202 of the printer 110 (S41), the printer control unit 202 controls the image generation control unit 203 according to the input print job, as in the first and second embodiments. An image is formed (printed) based on the document information related to the print job (S42). At this time, similarly to the second embodiment, the image generation control unit 203 adds the image data of the additional pattern of Y to the document image data based on the document information, and places the document image based on the document information on the paper. A printed image in which the and the additional pattern are integrated is formed (printed).

  In the third embodiment, the master image generation unit 217 of the image inspection apparatus 140 does not acquire the document information from the printer control unit 202 of the printer 110, but outputs the black (K), Write data is acquired for each of the colors cyan (C), magenta (M), and yellow (Y) (S43). Then, the master image generation unit 217 generates master image data from the writing data (S44).

  Here, the write data of Y used by the master image generation unit 217 to generate the master image data includes the data of the additional pattern as described above. Therefore, the master image data generated by the master image generation unit 217 includes an additional pattern as in the above-described second embodiment.

  On the other hand, the printed matter having the print image formed on the paper in the printer 110 is sent to the image inspection device 140, and the printed image on the printed matter is read by the print image reading unit 213 as in the second embodiment (S45). . The scan image thus obtained is sent to the comparison inspection unit 214 of the image inspection device 140 as shown in FIG. Upon acquiring the scan image data, the comparison inspection unit 214 acquires master image data including the additional pattern from the buffer 212. Then, using the result of comparing the scanned image data and the master image data, an image inspection process for inspecting a print image on a printed material is executed (S46). Note that the image inspection processing in the third embodiment is the same as that in the first embodiment.

  According to the third embodiment, the image data of the same additional pattern is included in both the master image data and the scanned image data that are compared with each other in the image inspection processing of the comparison inspection unit 214. Therefore, compared to the case where only one of the additional patterns is included, a situation in which an erroneous inspection result due to the additional pattern is obtained in the comparative inspection (image inspection) can be avoided, and an appropriate image inspection result can be obtained. be able to.

Moreover, according to the third embodiment, as in the second embodiment, an incorrect inspection result is output as compared with the case of performing the process of removing the additional pattern from the scan image as in the first embodiment. Things don't happen.
Further, according to the third embodiment, in order to generate master image data including an additional pattern from existing write data used by the image generation control unit 203, a process of adding an additional pattern as in the second embodiment is performed. Is unnecessary, and a simpler configuration and higher-speed processing are realized.

What has been described above is merely an example, and each embodiment has a specific effect.
(Aspect A)
A print image reading unit that acquires, as inspection target image data, image data of a recording material such as paper on which a document image based on document information and an additional information image such as an additional pattern based on additional information not included in the document information are formed. Inspection target image data acquisition means such as 213, reference image data generation means such as a master image generation unit 211 for generating reference image data such as master image data, etc., and the inspection target image data and the reference image data were compared. In the image inspection apparatus 140 having an image inspection processing execution unit such as a comparison inspection unit 214 that executes an image inspection process for inspecting an image on the recording material using the result, the inspection object image data acquisition unit acquires An additional pattern removing unit 215 for removing additional information image data corresponding to the additional information image from the inspection target image data; An information image removing unit, wherein the reference image data generating unit generates the reference image data from the document information, and the image inspection processing executing unit removes the additional information image data by the additional information image removing unit The image inspection process is performed using a result of comparison between the inspection target image data and the reference image data after the inspection.
In this aspect, the reference image data used when performing the image inspection processing of the recording material on which the image is formed is generated from the document information and does not include data for the additional information image based on the additional information. On the other hand, the inspection target image data to be compared with the reference image data is obtained from image data (inspection target image data) of a recording material on which a document image based on document information and an additional information image based on additional information are formed. The additional information image data corresponding to the information image has been removed. Therefore, neither the reference image data nor the inspection target image data to be compared with each other includes data corresponding to the additional information image. Therefore, in comparison with the case where only one of the additional information images includes the additional information image, it is possible to avoid a situation in which an erroneous inspection result due to the additional information image is output in the image inspection processing, and an appropriate image inspection result is obtained. Obtainable.

(Aspect B)
In the aspect A, the additional information image removing unit may be configured such that, when a predetermined image area (a pattern area or the like) including an image position where the additional information image is formed is a non-document image area where the document image does not exist, It is characterized in that removal of the additional information image data is performed, and when the predetermined image area is a document image area where the document image exists, the removal of the additional information image data is not performed.
According to this, even when the predetermined image area is the original image area, the pixels of the original image are erroneously recognized as being the pixels of the additional information image as compared with the case where the removal for the additional information image data is performed. The situation of removal does not occur. Therefore, it is possible to avoid a situation in which an erroneous inspection result due to erroneous removal of pixels of a document image is obtained, and it is possible to obtain an appropriate image inspection result.

(Aspect C)
Inspection target image data such as a print image reading unit 213 that acquires, as inspection target image data, image data of a recording material on which a document image based on document information and an additional information image based on additional information not included in the document information are formed. An acquisition unit, a reference image data generation unit such as a master image generation unit 211 that generates reference image data such as master image data, and the recording using the result of comparing the inspection target image data with the reference image data. In the image inspection apparatus 140 having an image inspection processing execution unit such as a comparison inspection unit 214 that executes an image inspection process for inspecting an image on a material, the reference image data generation unit is configured to perform the image inspection based on the document information and the additional information. It is characterized in that reference image data is generated.
In this aspect, the reference image data used when performing the image inspection processing of the recording material on which the image is formed is generated from the document information and the additional information, and includes data for the additional information image based on the additional information. . On the other hand, the inspection target image data to be compared with the reference image data is image data (inspection target image data) of a recording material on which a document image based on document information and an additional information image based on additional information are formed. It includes additional information image data corresponding to the additional information image. Therefore, both the reference image data and the inspection target image data to be compared with each other include data corresponding to the additional information image. Therefore, in comparison with the case where only one of the additional information images includes the additional information image, it is possible to avoid a situation in which an erroneous inspection result due to the additional information image is output in the image inspection processing, and an appropriate image inspection result is obtained. Obtainable.
Moreover, according to this aspect, as described in the above-described second embodiment, a situation in which an erroneous inspection result is output is suppressed as compared with the case where the processing for removing additional information image data from the inspection target image data is performed. it can.

(Aspect D)
Inspection target image data such as a print image reading unit 213 that acquires, as inspection target image data, image data of a recording material on which a document image based on document information and an additional information image based on additional information not included in the document information are formed. An acquisition unit, a reference image data generation unit such as a master image generation unit 217 for generating reference image data such as master image data, and the recording using the result of comparing the inspection target image data with the reference image data. In the image inspection apparatus 140 having an image inspection process execution unit such as a comparison inspection unit 214 that executes an image inspection process for inspecting an image on a material, the reference image data generation unit includes the original image, the additional information image, Generating the reference image data from the integrated image information (write data of C, M, Y, K, etc.) of the integrated image And butterflies.
In this aspect, the reference image data used when performing the image inspection process on the recording material on which the image is formed is generated from integrated image information of an integrated image obtained by integrating a document image and an additional information image. Includes data for an additional information image based on the additional information. On the other hand, the inspection target image data to be compared with the reference image data is image data (inspection target image data) of a recording material on which a document image based on document information and an additional information image based on additional information are formed. It includes additional information image data corresponding to the additional information image. Therefore, both the reference image data and the inspection target image data to be compared with each other include data corresponding to the additional information image. Therefore, in comparison with the case where only one of the additional information images includes the additional information image, it is possible to avoid a situation in which an erroneous inspection result due to the additional information image is output in the image inspection processing, and an appropriate image inspection result is obtained. Obtainable.
Moreover, according to this aspect, as described in the above-described third embodiment, a situation in which an erroneous inspection result is output is suppressed as compared with the case where the processing for removing additional information image data from the inspection target image data is performed. it can.
Furthermore, according to this aspect, as described in the third embodiment, a simpler configuration and higher-speed processing can be realized.

(Aspect E)
An image forming apparatus such as a printer 110 for forming, on a recording material, an integrated image in which a document image based on document information and an additional information image based on additional information not included in the document information are integrated; In the image forming system 1 including the image inspection apparatus 140 that inspects an image formed on a recording material, the image inspection apparatus according to any one of the aspects A to D is used as the image inspection apparatus. It is characterized by.
An appropriate image inspection result for the image formed on the recording material by the image forming apparatus can be obtained.

1 Image Forming System 110 Printer 120 Operation Unit 130 Paper Feed Unit 140 Image Inspection Devices 141, 142 Scanner 143 Printed Material Transport Path 150 Stacker 201 RIP
202 Printer control unit 203 Image generation control unit 203E Additional pattern addition processing units 211 and 217 Master image generation unit 212 Buffer 213 Print image reading unit 214 Comparative inspection unit 215 Additional pattern removal unit 216 Additional pattern addition unit

JP 2014-145885 A

Claims (3)

Inspection target image data acquisition means for acquiring, as inspection target image data, image data of a recording material on which a document image based on document information and an additional information image based on additional information not included in the document information are formed,
Reference image data generating means for generating reference image data,
An image inspection apparatus comprising: an image inspection processing execution unit configured to execute an image inspection processing for inspecting an image on the recording material using a result of comparing the inspection target image data with the reference image data.
With respect to the inspection target image data acquired by the inspection target image data acquiring means , a pixel block including a plurality of pixels corresponding to the dot size of the additional information image is shifted one pixel at a time, and a pixel block including the additional information image is shifted. Identifying a position, having additional information image removing means for removing additional information image data corresponding to the additional information image from the inspection target image data ,
The image inspection process execution unit executes the image inspection process using a result of comparing the inspection target image data after removing the additional information image data by the additional information image removal unit with the reference image data. An image inspection apparatus, characterized in that: The image inspection apparatus according to claim 1,
The additional information image removing means, when a predetermined image area including an image position where the additional information image is formed is a non-document image area where the document image does not exist, performs removal of the additional information image data, When the predetermined image area is a document image area where the document image exists, the image inspection apparatus does not remove the additional information image data. An image forming apparatus for forming, on a recording material, an integrated image in which a document image based on document information and an additional information image based on additional information not included in the document information are integrated;
An image forming system including: an image inspection device that inspects an image formed on a recording material by the image forming device;
An image forming system using the image inspection device according to claim 1 or 2 as the image inspection device.

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