Multi-page printing quality inspection method, device, system, equipment, medium and product

Abstract

The present invention discloses a multi-page printed quality inspection method, device, system, equipment, medium and product, and relates to the field of electronic digital data processing technology. The method is to determine the one-to-one correspondence between the multi-page scanned images and the multi-page reference images of the printed matter to be inspected, and grayscale process each pair of scanned grayscale images and reference grayscale images, and then for each pair of scanned images and reference images, firstly perform a pixel-level grayscale comparison to determine the corresponding minimum rectangular frame containing all grayscale contrast-inconsistent pixels, and when the area ratio of the corresponding minimum rectangular frame is less than or equal to a preset ratio threshold, from the corresponding image pair, the corresponding scanned and reference sub-images surrounded by the minimum rectangular frame are cut out, and finally the image difference description generation model is output to obtain the corresponding image difference description text, and the minimum rectangular frame and the description text are loaded and displayed on the corresponding image pair, so that the quality inspection efficiency can be greatly improved and human errors can be avoided.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic digital data processing, and in particular relates to a multi-page printing quality inspection method, device, system, equipment, medium and product. Background Art

[0002] In the process of editing, large-scale imposition, halftone rasterization and printing of the original files to be printed by the customers, there may be problems such as mistakes in the original files to be printed, changes in places that should not be moved, loss of file pixels, errors in loading small page files in imposition, loss of pixels in small page file layers, and errors in the interpretation of images and texts in the rasterization process. There are also printing problems caused by plates or printing machines. Therefore, after the printed products corresponding to the original files to be printed are finally obtained, quality inspection and comparison (including printing first inspection comparison and printing random inspection comparison, etc.) are required to finally confirm whether the printed products are qualified. In addition, when the paper manuscript is used as the signature standard, it is also necessary to verify the complete consistency of the matching printed electronic files, that is, by proving that the electronic files are completely consistent with the paper manuscript image content after printing, it is used to find out whether the electronic files and the printed signature paper manuscripts are 100% consistent.

[0003] At present, the specific means of the existing printing quality inspection and comparison scheme for evaluating the difference based on the inspection results after the page pixel inspection of the matched image is: first calculate the ratio B of the gray value difference C and the preset gray value difference C0 (that is, set B = C ÷ C0), and then determine the difference evaluation value according to the comparison result of the ratio and the preset ratio; but the difference area is not located and the difference description is given, so that the quality inspector still needs to manually locate the difference area and perceive the difference description after perceiving the difference evaluation value (for example, there are three levels: E1, E2 and E3), so as to perform the corresponding difference elimination processing in the subsequent printing process to ensure the quality of the subsequent printed products. The aforementioned method of manually locating the difference area and perceiving the difference description obviously has the problems of low efficiency and easy human error, and is particularly not suitable for quality inspection and comparison of multi-page printed products. Therefore, how to automatically locate the difference area and give the difference description in the multi-page printing quality inspection process to facilitate the corresponding difference elimination processing in the subsequent printing process to ensure the quality of the subsequent printed products is a topic that technicians in this field urgently need to study. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-page print quality inspection method, device, system, computer equipment, computer-readable storage medium and computer program product to solve the problems of low efficiency and easy human error in existing print quality inspection and comparison schemes because they still require manual labor to locate the difference area and perceive the difference description.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] In a first aspect, a multi-page printing quality inspection method is provided, comprising:

[0007] Acquire a scanned image file and a reference image file of a printed product to be inspected, wherein the printed product to be inspected is a multi-page printed product, the scanned image file contains multiple pages of scanned images, and the reference image file contains multiple pages of reference images;

[0008] Determine a one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and make the scanned images and the corresponding reference images have the same resolution and size, the same size as the plate core, or a size that is scaled 1:1 in length and width;

[0009] Performing grayscale processing on each pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, respectively, to obtain each pair of scanned grayscale images and reference grayscale images;

[0010] For each pair of scanned images and reference images, a plurality of first pixel points whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale image are determined according to a preset grayscale threshold interval, and the grayscale values ​​of each first pixel point in the plurality of first pixel points in the corresponding grayscale image pair are respectively compared to determine a corresponding second pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale image pair;

[0011] For each pair of scanned images and reference images, if the total number of the corresponding second pixel points is equal to zero, it is determined that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, a first minimum rectangular frame corresponding to all the corresponding second pixel points and within any one of the grayscale images is determined, wherein the first minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding second pixel points;

[0012] For each pair of scanned images and reference images, if the area ratio of the corresponding first minimum rectangular frame in any grayscale image is less than or equal to a preset first ratio threshold, it is determined that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, a corresponding first scanned sub-image and a first reference sub-image enclosed by the corresponding first minimum rectangular frame are obtained from the corresponding image pair;

[0013] For each pair of scanned images and reference images, the corresponding first scanned sub-image and the first reference sub-image are imported into a pre-trained image difference description generation model, the corresponding first image difference description text is output, and the first minimum rectangular box and the first image difference description text are loaded and displayed on the corresponding image pair.

[0014] Based on the above invention, a new printing quality inspection and comparison scheme is provided, which can automatically locate the difference area and give the difference description in the process of multi-page printing quality inspection. That is, after determining the one-to-one correspondence between the multi-page scanned images and the multi-page reference images of the printed matter to be inspected and graying them to obtain each pair of scanned grayscale images and reference grayscale images, for each pair of scanned images and reference images, firstly, a pixel-level grayscale comparison is performed to determine the corresponding minimum rectangular frame containing all the grayscale contrast inconsistent pixels, and when the area proportion of the corresponding minimum rectangular frame is less than or equal to the preset ratio threshold, the corresponding scanned sub-image and the reference sub-image surrounded by the minimum rectangular frame are cut out from the corresponding image pair, and finally, the image difference description generation model is output to obtain the corresponding image difference description text, and the minimum rectangular frame and the image difference description text are loaded and displayed on the corresponding image pair, so that the difference area can be automatically located and the difference description can be given in the process of multi-page printing quality inspection, which greatly improves the quality inspection efficiency and avoids human errors, and then it can be beneficial to perform the corresponding difference elimination processing in the subsequent printing process, ensure the quality of the subsequent printed matter, and facilitate practical application and promotion.

[0015] In a possible design, when the printed product to be inspected is a multi-page printed product for first inspection, the scanned image file is a multi-page scanned image file of the multi-page printed product for first inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of the large-format printed product after multi-page imposition, and the reference image file is a multi-page electronic image file corresponding to the multi-page printed product for first inspection or a large-format electronic image file after multi-page imposition;

[0016] Alternatively, when the printed matter to be inspected is a multi-page printed matter for random inspection, the scanned image file is a multi-page scanned image file of the multi-page printed matter for random inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of the large-format printed matter after multi-page imposition, and the reference image file is a multi-page scanned image file of the multi-page printed matter confirmed to be correct in the first inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of the large-format printed matter after multi-page imposition;

[0017] Alternatively, when the printed matter to be inspected is a first multi-page printed matter, the scanned image file is a multi-page scanned image file of the first multi-page printed matter, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by folding, cutting, and trimming the large-format printed matter after multi-page imposition through double-sided scanning; the reference image file is a multi-page scanned image file of the second multi-page printed matter, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by folding, cutting, and trimming the large-format printed matter after multi-page imposition through double-sided scanning, wherein the first multi-page printed matter and the second multi-page printed matter are different printed matters.

[0018] In a possible design, for each pair of scanned images and reference images, determining a plurality of first pixel points in any corresponding grayscale image and having grayscale values ​​belonging to the grayscale threshold interval according to a preset grayscale threshold interval includes:

[0019] For each pair of scanned images and reference images, a plurality of first pixel points in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval are determined according to a preset grayscale threshold interval, and it is determined whether the total number of the plurality of first pixel points is lower than a preset first pixel point number threshold, and if so, the grayscale threshold interval is adjusted and updated, and then a plurality of first pixel points in any grayscale image and whose grayscale values ​​belong to a new grayscale threshold interval are determined again according to the new grayscale threshold interval, until it is determined that the total number of the plurality of first pixel points is greater than or equal to the first pixel point number threshold;

[0020] And / or, for each pair of scanned images and reference images, determine a plurality of first pixel points in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and determine whether the total number of the plurality of first pixel points is higher than a preset second pixel number threshold; if so, adjust and update the grayscale threshold interval, and then determine a plurality of first pixel points in any grayscale image and whose grayscale values ​​belong to the new grayscale threshold interval according to the new grayscale threshold interval, until it is determined that the total number of the plurality of first pixel points is less than or equal to the second pixel number threshold.

[0021] In a possible design, for each pair of scanned images and reference images, determining a plurality of first pixel points in any corresponding grayscale image and having grayscale values ​​belonging to the grayscale threshold interval according to a preset grayscale threshold interval includes:

[0022] For each pair of scanned images and reference images, a plurality of first pixel points whose grayscale values ​​belong to a preset grayscale threshold interval in any corresponding grayscale image are determined, and any grayscale image is gridded into a plurality of image sub-regions of the same size, and then the number of the first pixel points in each of the plurality of image sub-regions and the number standard deviation of the plurality of image sub-regions are obtained by statistics, and finally, it is determined whether the number standard deviation is higher than a preset standard deviation threshold, and if so, the grayscale threshold interval is adjusted and updated, and then a plurality of first pixel points whose grayscale values ​​belong to a new grayscale threshold interval in any grayscale image are determined again according to the new grayscale threshold interval, until it is determined that the number standard deviation is less than or equal to the standard deviation threshold.

[0023] In a possible design, after determining the first minimum rectangular frame corresponding to each pair of scanned images and the reference image and within any grayscale image, the method further includes:

[0024] For a pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, if the area ratio of the corresponding first minimum rectangular frame in any corresponding grayscale image is greater than a preset second ratio threshold, a corresponding scanned grayscale sub-image and a reference grayscale sub-image surrounded by the corresponding first minimum rectangular frame are intercepted from the corresponding grayscale image pair, wherein the second ratio threshold is greater than the first ratio threshold;

[0025] Performing gridding processing on the scanned grayscale sub-image and the reference grayscale sub-image respectively, to obtain a plurality of scanned grayscale sub-images and a plurality of reference grayscale sub-images corresponding to the plurality of scanned grayscale sub-images one by one;

[0026] For each pair of scanned grayscale grandson images and reference grayscale grandson images that have a mapping relationship among the multiple scanned grayscale grandson images and the multiple reference grayscale grandson images, determine a plurality of third pixel points whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale grandson image according to a preset grayscale threshold interval, and respectively compare the grayscale values ​​of each third pixel point in the corresponding grayscale grandson image pair among the multiple third pixel points to determine a corresponding fourth pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale grandson image pair;

[0027] For each pair of the scanned grayscale grandson images and the reference grayscale grandson images, if the number of the corresponding fourth pixel points is non-zero, determining a corresponding second minimum rectangular frame within any of the grayscale grandson images according to all the corresponding fourth pixel points, wherein the second minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding fourth pixel points;

[0028] For each pair of scanned grayscale sub-images and reference grayscale sub-images, if the area ratio of the corresponding second minimum rectangular frame in any grayscale image is greater than a preset third ratio threshold, a corresponding second scanned sub-image and a second reference sub-image enclosed by the corresponding second minimum rectangular frame are obtained from the pair of scanned images and reference images;

[0029] For each pair of scanned grayscale sub-images and reference grayscale sub-images, the corresponding second scanned sub-image and the second reference sub-image are imported into a pre-trained image difference description generation model, and the corresponding second image difference description text is output, and the second minimum rectangular box and the second image difference description text are loaded and displayed on the pair of scanned images and reference images.

[0030] In a second aspect, a multi-page printing quality inspection device is provided, comprising an image file acquisition unit, a correspondence determination unit, a grayscale processing unit, a pixel grayscale comparison unit, a rectangular frame determination unit, a sub-image interception unit and a difference description generation unit;

[0031] The image file acquisition unit is used to acquire a scanned image file and a reference image file of the printed product to be inspected, wherein the printed product to be inspected is a multi-page printed product, the scanned image file contains multiple pages of scanned images, and the reference image file contains multiple pages of reference images;

[0032] The correspondence determination unit is communicatively connected to the image file acquisition unit, and is used to determine a one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and to make the scanned images and the corresponding reference images have the same resolution and size, the same size as the plate core, or a size that is scaled 1:1 in length and width;

[0033] The grayscale processing unit is communicatively connected to the corresponding relationship determining unit, and is used to perform grayscale processing on each pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, respectively, to obtain each pair of scanned grayscale images and reference grayscale images;

[0034] The pixel grayscale comparison unit is communicatively connected to the grayscale processing unit, and is used to determine, for each pair of scanned images and reference images, a plurality of first pixel points in any corresponding grayscale image whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and respectively compare the grayscale values ​​of each first pixel point in the corresponding grayscale image pair among the plurality of first pixel points, and determine a corresponding second pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale image pair;

[0035] The rectangular frame determination unit is communicatively connected to the pixel grayscale comparison unit, and is used for determining, for each pair of scanned images and reference images, that the total number of the corresponding second pixel points is equal to zero, that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, determining a first minimum rectangular frame corresponding to all the corresponding second pixel points and within any grayscale image, wherein the first minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding second pixel points;

[0036] The sub-image interception unit is communicatively connected to the image file acquisition unit and the rectangular frame determination unit, respectively, and is used for determining, for each pair of scanned images and reference images, that the printed product to be inspected has passed the quality inspection on the corresponding page if the area ratio of the corresponding first minimum rectangular frame in any grayscale image is less than or equal to a preset first ratio threshold, and otherwise, intercepting the corresponding first scanned sub-image and the first reference sub-image surrounded by the corresponding first minimum rectangular frame from the corresponding image pair;

[0037] The difference description generation unit is communicatively connected to the sub-image capture unit, and is used for importing the corresponding first scanned sub-image and the first reference sub-image into a pre-trained image difference description generation model for each pair of scanned images and reference images, outputting the corresponding first image difference description text, and loading and displaying the first minimum rectangular box and the first image difference description text on the corresponding image pair.

[0038] In a third aspect, the present invention provides a multi-page printing quality inspection system, comprising a scanner, a processing device and a display;

[0039] The scanner is communicatively connected to the processing device, and is used to scan and obtain a scanned image file of the printed matter to be inspected, and transmit the scanned image file to the processing device;

[0040] The processing device is communicatively connected to the display, and is used to execute the multi-page printing quality inspection method as described in the first aspect or any possible design of the first aspect, and transmit the loading results obtained by loading on the scanned image and the reference image to the display;

[0041] The display is used to display the loading result.

[0042] In a fourth aspect, the present invention provides a computer device comprising a memory, a processor and a transceiver which are communicatively connected in sequence, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program to execute the multi-page printing quality inspection method as described in the first aspect or any possible design of the first aspect.

[0043] In a fifth aspect, the present invention provides a computer-readable storage medium having instructions stored thereon, which, when executed on a computer, executes a multi-page printing quality inspection method as described in the first aspect or any possible design of the first aspect.

[0044] In a sixth aspect, the present invention provides a computer program product, including a computer program or instructions, which, when executed by a computer, implements the multi-page printing quality inspection method as described in the first aspect or any possible design of the first aspect.

[0045] Beneficial effects of the above scheme:

[0046] (1) The present invention creatively provides a new printing quality inspection and comparison scheme that can automatically locate the difference area and give the difference description in the process of multi-page printing quality inspection. That is, after determining the one-to-one correspondence between the multi-page scanned images and the multi-page reference images of the printed matter to be inspected and graying them to obtain each pair of scanned grayscale images and reference grayscale images, for each pair of scanned images and reference images, firstly, a pixel-level grayscale comparison is performed to determine the corresponding minimum rectangular frame that contains all the grayscale contrast-inconsistent pixels, and when the area ratio of the corresponding minimum rectangular frame is less than or equal to a preset ratio threshold, the corresponding scanned sub-image and reference sub-image surrounded by the minimum rectangular frame are cut out from the corresponding image pair. Finally, the image difference description generation model is output to obtain the corresponding image difference description text, and the minimum rectangular frame and image difference description text are loaded and displayed on the corresponding image pair. In this way, the difference area can be automatically located and the difference description can be given in the process of multi-page printing quality inspection, which greatly improves the quality inspection efficiency and avoids human errors. It is also beneficial to perform corresponding difference elimination processing in the subsequent printing process to ensure the quality of the subsequent printed matter.

[0047] (2) When the initial difference area is too large, the difference area can be further finely located and the corresponding difference description content can be given to improve the user experience and facilitate practical application and promotion;

[0048] (3) It also provides an economical solution for first-article inspection / sampling of printed materials, that is, the scanner used is economical, avoiding the high cost of large scanners required for scanning large printed materials;

[0049] (4) It also provides convenience. That is, due to the lightweight nature of the scanning device, the entire device system is light and portable, and can be used in scenarios such as pre-press paper proofreading, first-piece inspection, printing sampling, and content proofreading and quality inspection of the entire book before binding of printed materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 A schematic flow chart of a multi-page printing quality inspection method provided in an embodiment of the present application.

[0052] Figure 2 This is an example diagram of a large-format paper after multiple pages of imposition provided in an embodiment of the present application.

[0053] Figure 3 This is an example diagram of the result of arranging multiple pages on both sides of a large-format paper provided in an embodiment of the present application, wherein: Figure 3 (a) in the figure shows an example of a multi-page layout result on the front side of a large-format paper. Figure 3 (b) in the figure shows an example of the result of arranging multiple pages on the back side of a large format paper.

[0054] Figure 4 This is an example diagram of the first minimum rectangular frame in any grayscale image provided by an embodiment of the present application.

[0055] Figure 5 A schematic diagram of the structure of a multi-page printing quality inspection device provided in an embodiment of the present application.

[0056] Figure 6 A schematic diagram of the structure of a multi-page printing quality inspection system provided in an embodiment of the present application.

[0057] Figure 7 A schematic diagram of the structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in combination with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structures of the drawings is only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these embodiments without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0059] It should be understood that although the terms first and second, etc. may be used herein to describe various objects, these objects should not be limited by these terms. These terms are only used to distinguish one object from another object. For example, a first object can be referred to as a second object, and similarly, a second object can be referred to as a first object without departing from the scope of the exemplary embodiments of the present invention.

[0060] It should be understood that the term "and / or" that may appear in this document is merely a description of the association relationship between associated objects, indicating that there may be three relationships. For example, A and / or B can indicate three situations: A exists alone, B exists alone, or A and B exist at the same time. For another example, A, B and / or C can indicate the existence of any one of A, B and C or any combination of them. The term " / and" that may appear in this document describes another type of association object relationship, indicating that there may be two relationships. For example, A / and B can indicate two situations: A exists alone or A and B exist at the same time. In addition, the character " / " that may appear in this document generally indicates that the previous and next associated objects are in an "or" relationship.

[0061] Example

[0062] like Figure 1 As shown, the multi-page printing quality inspection method provided in the first aspect of this embodiment can be, but is not limited to, executed by a computer device having certain computing resources and communicating with a scanner, such as a platform server, a personal computer (PC, which refers to a multi-purpose computer with a size, price and performance suitable for personal use; desktops, laptops, small laptops, tablets and ultrabooks are all personal computers), smart phones, personal digital assistants (PDA) or wearable devices. Figure 1 As shown, the multi-page printing quality inspection method may include but is not limited to the following steps S1 to S7.

[0063] S1. Obtain a scanned image file and a reference image file of a printed product to be inspected, wherein the printed product to be inspected is a multi-page printed product, the scanned image file contains multiple pages of scanned images, and the reference image file contains multiple pages of reference images.

[0064] In step S1, the printed product to be inspected is a printing result obtained by printing the original document to be printed by the customer and used as a comparative quality inspection object. It can be the first printed product in the batch printing result or a non-first printed product. Specifically, when the printed matter to be inspected is a multi-page printed matter for the first inspection (i.e., the first printed matter in the batch printing results), the scanned image file may be, but is not limited to, a multi-page scanned image file of the multi-page printed matter for the first inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by folding, cutting, and trimming the large-format printed matter after multi-page imposition through double-sided scanning, and the reference image file may be, but is not limited to, a multi-page electronic image file or a large-format electronic image file after multi-page imposition corresponding to the multi-page printed matter for the first inspection; or, when the printed matter to be inspected is a multi-page printed matter for random inspection (i.e., not the first printed matter in the batch printing results), the scanned image file may be, but is not limited to, a multi-page scanned image file of the multi-page printed matter for the random inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by folding, cutting, and trimming the large-format printed matter after multi-page imposition through double-sided scanning, and the reference image file may be, but is not limited to, a scanned image file confirmed to be correct in the first inspection. A multi-page scanned image file of a multi-page printed product, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of a large-format printed product after multi-page imposition; or, when the printed product to be inspected is the first multi-page printed product, the scanned image file may be but is not limited to the multi-page scanned image file of the first multi-page printed product, the large-format scanned image file after multi-page imposition, or the scanned image file obtained by double-sided scanning after folding, cutting and trimming of a large-format printed product after multi-page imposition; the reference image file may be but is not limited to the multi-page scanned image file of the second multi-page printed product, the large-format scanned image file after multi-page imposition, or the scanned image file obtained by double-sided scanning after folding, cutting and trimming of a large-format printed product after multi-page imposition, wherein the first multi-page printed product and the second multi-page printed product are different printed products (for example, two different printed products based on the same original file to be printed and produced by different printing presses). The aforementioned large-format printed product after multiple pages of imposition is folded, cut and trimmed, and then scanned by double-sided scanning to obtain a scanned image file. Figure 2As shown in the figure, after folding, cutting and de-edging a large-format paper (a single sheet of paper contains 8 pages of content), the image file obtained by double-sided scanning of the obtained multiple pages of paper can be obtained by, but not limited to, using an existing sheet-fed scanner to scan the multiple pages of paper on one side or both sides. The aforementioned multi-page large-format scanned image file refers to an image file obtained by directly scanning the printed multiple pages of large-format paper after imposition, and can be obtained by, but not limited to, using an existing large-scale scanner to scan the multiple pages of large-format paper after imposition on one side or both sides. The aforementioned multi-page electronic image file or multi-page large-format electronic image file after imposition can be directly the original file to be printed by the customer, or it can be a new electronic image file obtained by conventional processing based on the original file to be printed by the customer. The specific method of obtaining the scanned image file can be, but not limited to, obtained by transmitting it from a scanner after scanning. The specific method of obtaining the reference image file can be, but not limited to, imported by a quality inspector, wherein the reference image is used as a reference for comparative quality inspection. In addition, the printed matter to be inspected can be a single-sided print or a double-sided print.

[0065] S2. Determine a one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and make the scanned images and the corresponding reference images have the same resolution and size, the same size as the plate core, or a size that is scaled 1:1 in length and width.

[0066] In the step S2, specifically, determining a one-to-one correspondence between the multi-page scanned images and the multi-page reference images includes but is not limited to: in the case where the page number sequence of the multi-page reference images is a known condition, if the scanned image file is a multi-page scanned image file, then the scanning sequence of the multi-page scanned images is matched with the page number sequence of the multi-page reference images to obtain a one-to-one correspondence between the multi-page scanned images and the multi-page reference images (for example, the first scanned image in the multi-page scanned images corresponds to the first page reference image in the multi-page reference images); and if the scanned image file is a large-format scanned image file after multi-page imposition, first based on the folding logic (that is, common sense in the field of printing technology, for example Figure 3The page number sequence of the multi-page scanned images is determined based on the multi-page arrangement result on both sides of a large-format paper and based on the folding requirements, and then the page number sequence of the multi-page scanned images is matched with the page number sequence of the multi-page reference images to obtain a one-to-one correspondence between the multi-page scanned images and the multi-page reference images (for example, the last page scanned image in the multi-page scanned images corresponds to the last page reference image in the multi-page reference images). In addition, when the reference image file is a multi-page electronic image file, the page number sequence of the multi-page reference images can be obtained directly based on the sequence of electronic images; when the reference image file is a multi-page scanned image file, the page number sequence of the multi-page reference images can be obtained based on the scanning sequence; when the reference image file is a large-format electronic image file after multi-page imposition or a large-format scanned image file after multi-page imposition, the page number sequence of the multi-page reference images can be obtained based on the folding logic.

[0067] In step S2, specifically, making the scanned image and the corresponding reference image have the same resolution and the same size includes but is not limited to: taking the size and resolution of any one of the scanned image and the corresponding reference image as a reference, performing conventional image compression, image expansion and / or image resolution conversion on the other image in the scanned image and the corresponding reference image, so that the two images have the same size and resolution, for example, the resolution of both images is 300dpi or 600dpi. In addition, the specific means of making the scanned image and the corresponding reference image have the same resolution and the same size of the plate core or the size of the length and width being scaled 1:1 is also an existing conventional technical means; the multi-page scanned image and the multi-page reference image need to be consistent in the number of pages. If they are inconsistent, it can be directly determined that the printed product to be inspected has not passed the quality inspection.

[0068] In the step S2, in order to verify the one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, preferably, after determining the one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, the method also includes but is not limited to the following steps S21 to S24.

[0069] S21. For each page scanned image in the plurality of pages scanned images, optical character recognition technology is applied to extract corresponding page content text from the corresponding scanned image, and the number of corresponding words in the page content text is counted.

[0070] In the step S21, the optical character recognition technology is the existing OCR (Optical Character Recognition) technology, so the page content text can be conventionally extracted from the scanned image.

[0071] S22. For each page reference image in the plurality of pages reference images, the optical character recognition technology is applied to extract the corresponding page content text from the corresponding reference image, and the number of corresponding words in the page content text is counted.

[0072] S23. Arrange the scanned images of each page in order from high to low in terms of word count to obtain a first image queue, and also arrange the reference images of each page in order from high to low in terms of word count to obtain a second image queue.

[0073] S24. For each pair of scanned images and reference images with the same serial number in the first image queue and the second image queue, if the corresponding two images do not have a mapping relationship in the one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and the corresponding two pages of content text have content consistency characteristics, an output is displayed to indicate that there is a mapping relationship mismatch between the corresponding two images, so as to remind quality inspectors to conduct manual inspection and correct the mapping relationship.

[0074] In the step S24, for example, if the fifth scanned image in the first image queue and the fifth reference image in the second image queue do not have a mapping relationship in the one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and the page content text of the fifth scanned image and the page content text of the fifth reference image have content consistency characteristics, it means that the fifth scanned image and the fifth reference image should have a mapping relationship but do not have it, and then it is necessary to output a reminder message indicating that there is a mismatch in the mapping relationship between the fifth scanned image and the fifth reference image, so as to remind the quality inspector to perform manual inspection and correct the mapping relationship. In addition, for each pair of scanned images and reference images with the same sequence number in the first image queue and the second image queue, if the corresponding two images have a mapping relationship in the one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and the corresponding two pages of content text have content inconsistency characteristics, then a reminder message indicating that there is a mismatch in the mapping relationship between the corresponding two images is also output to remind the quality inspector to perform manual inspection and correct the mapping relationship. In addition, the above-mentioned specific method of determining whether the content texts of two pages have the characteristic of content consistency can be conventionally implemented based on, but not limited to, indicators such as word frequency, edit distance and / or Jaccard distance.

[0075] S3. Perform grayscale processing on each pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, respectively, to obtain each pair of scanned grayscale images and reference grayscale images.

[0076] In the step S3, specifically, the scanned image is subjected to the grayscale processing to obtain the scanned grayscale image; and the reference image is subjected to the grayscale processing to obtain the reference grayscale image.

[0077] S4. For each pair of scanned images and reference images, determine a plurality of first pixel points in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and compare the grayscale values ​​of each first pixel point in the corresponding grayscale image pair respectively, and determine the corresponding second pixel point that does not have the grayscale value consistency characteristic in the corresponding grayscale image pair.

[0078] In step S4, any grayscale image is a scanned grayscale image or a reference grayscale image in a pair of scanned grayscale images and reference grayscale images corresponding to each pair of scanned images and reference images. The grayscale threshold interval is used to screen feature pixels involved in pixel-level comparison, which can be set in advance by a quality inspector or randomly generated in advance, for example, [100, 120]. Considering that the total number of feature pixels involved in pixel-level comparison should not be too small, so as not to affect the accuracy of the subsequent difference area positioning results, preferably, for each pair of scanned images and reference images, multiple first pixels in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval are determined according to a preset grayscale threshold interval, including but not limited to the following steps: for each pair of scanned images and reference images, multiple first pixels in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval are determined according to a preset grayscale threshold interval, and it is determined whether the total number of the multiple first pixels is lower than the preset first pixel number threshold, if so, the grayscale threshold interval is adjusted and updated, and then the multiple first pixels in any grayscale image and whose grayscale values ​​belong to the new grayscale threshold interval are determined again according to the new grayscale threshold interval, until it is determined that the total number of the multiple first pixels is greater than or equal to the first pixel number threshold. The specific method of adjusting and updating the grayscale threshold interval may be, but is not limited to, extending the interval or changing the interval. In addition, it is also considered that the total number of characteristic pixels participating in the pixel level comparison should not be too large, so as not to lose the meaning of screening characteristic pixels. Preferably, for each pair of scanned images and reference images, multiple first pixels whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale image are determined according to the preset grayscale threshold interval, and it is determined whether the total number of the multiple first pixels is higher than the preset second pixel number threshold. If so, the grayscale threshold interval is adjusted and updated, and then the multiple first pixels whose grayscale values ​​belong to the new grayscale threshold interval in any grayscale image are determined again according to the new grayscale threshold interval until it is determined that the total number of the multiple first pixels is less than or equal to the second pixel number threshold. The specific method of adjusting and updating the grayscale threshold interval can be, but not limited to, shrinking the interval or changing the interval. In addition, the second pixel number threshold needs to be greater than the first pixel number threshold; the first pixel number threshold and the second pixel number threshold can be pre-set based on the corresponding image size or image resolution. That is, the larger the image size or the higher the image resolution, the larger the first pixel number threshold and the second pixel number threshold are set, and vice versa.

[0079] In the step S4, it is also considered that the multiple feature pixel points involved in the pixel level comparison need to have a uniform distribution characteristic to avoid the situation where the pixel level comparison occurs in the local area, thereby affecting the accuracy of the subsequent difference area positioning results. Preferably, for each pair of scanned images and reference images, a plurality of first pixel points whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale image are determined according to a preset grayscale threshold interval, including but not limited to the following steps: for each pair of scanned images and reference images, a plurality of first pixel points whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale image are determined according to a preset grayscale threshold interval. The method comprises the following steps: determining a plurality of first pixel points of a grayscale image in a grayscale interval, and gridding the grayscale image into a plurality of image sub-regions of the same size, and then obtaining the number of the first pixel points in each of the plurality of image sub-regions and the number standard deviation of the plurality of image sub-regions by statistics, and finally determining whether the number standard deviation is higher than a preset standard deviation threshold value. If so, adjusting and updating the grayscale threshold interval, and then determining a plurality of first pixel points in the grayscale image whose grayscale values ​​belong to the new grayscale threshold interval again according to the new grayscale threshold interval, until determining that the number standard deviation is less than or equal to the standard deviation threshold value. For example, assuming that the size of the grayscale image is 6000×9000, the grayscale image can be gridded into 100 image sub-regions of a size of 600×900, and then counting the number of the first pixel points in each of the 100 image sub-regions and the number average and number standard deviation of the 100 image sub-regions. In addition, the standard deviation threshold and / or the total number of areas of the multiple image sub-areas can also be pre-set in a positive correlation based on the corresponding image size or image resolution, that is, the larger the image size or the higher the image resolution, the larger the standard deviation threshold and / or the total number of areas of the multiple image sub-areas is set, and vice versa.

[0080] In the step S4, specifically, the grayscale values ​​of each first pixel point in the plurality of first pixel points in the corresponding grayscale image pair are compared respectively to determine the corresponding second pixel point that does not have the grayscale value consistency characteristic in the corresponding grayscale image pair, including but not limited to: if the absolute value of the difference in the grayscale value of a certain first pixel point in the plurality of first pixel points in the corresponding grayscale image pair is greater than a preset grayscale threshold, then it is determined that the certain first pixel point does not have the grayscale value consistency characteristic in the corresponding grayscale image pair, otherwise it is determined that the certain first pixel point has the grayscale value consistency characteristic in the corresponding grayscale image pair. In addition, the aforementioned grayscale threshold is exemplified but not limited to 10.

[0081] S5. For each pair of scanned images and reference images, if the total number of the corresponding second pixel points is equal to zero, it is determined that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, based on all the corresponding second pixel points, the corresponding first minimum rectangular frame within any grayscale image is determined, wherein the first minimum rectangular frame refers to a rectangular frame with the smallest area used to enclose all the corresponding second pixel points.

[0082] In step S5, for example, if the second pixel point is represented by a black dot, the first minimum rectangular frame can be represented by Figure 4 In addition, the specific determination method of the first minimum rectangular frame can be, but is not limited to, conventionally determined based on the coordinates of all the second pixel points in any grayscale image.

[0083] S6. For each pair of scanned images and reference images, if the area ratio of the corresponding first minimum rectangular frame in any grayscale image is less than or equal to the preset first ratio threshold, it is determined that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, the corresponding first scanned sub-image and first reference sub-image surrounded by the corresponding first minimum rectangular frame are captured from the corresponding image pair.

[0084] In step S6, the first minimum rectangular frame is the located difference area; the first ratio threshold is used as a criterion for measuring whether the difference area can be ignored in this comparison quality inspection process, that is, if the area of ​​the first minimum rectangular frame in any grayscale image is too small, the corresponding difference area can be ignored in this comparison quality inspection process, and it is determined that the print to be inspected has passed the quality inspection on the corresponding page, otherwise it is not. In addition, the first ratio threshold is 5% for example.

[0085] S7. For each pair of scanned images and reference images, the corresponding first scanned sub-image and the first reference sub-image are imported into a pre-trained image difference description generation model, the corresponding first image difference description text is output, and the first minimum rectangular box and the first image difference description text are loaded and displayed on the corresponding image pair.

[0086] In step S7, the goal of the image difference captioning (IDC) model is to compare two similar images and capture the visual differences between them, and then describe these differences in natural language. Specifically, it can be implemented by, but not limited to, using an existing model based on pre-extracted object-level difference features, a model based on a dynamic related attention mechanism, a difference description model based on a Transformer (a classic NLP model proposed by a Google team in 2017) structure, and / or a model that combines a semantic segmentation model and a graph convolutional neural network to describe image differences. Specifically, the first image difference description text can be, but not limited to, composed of a number of keywords, so as to form a difference description content that can be intuitively perceived by quality inspectors. The specific pre-training process of the image difference description generation model can also be implemented with reference to the prior art. In detail, loading and displaying the first minimum rectangular box and the first image difference description text on the image pair can be specifically: loading and displaying the first minimum rectangular box and the first image difference description text on the scanned image and / or the reference image, so that the quality inspectors can intuitively perceive the difference area positioning result and the given difference description content. In addition, if the printed product to be inspected passes the quality inspection on all pages, it can be determined that the printed product to be inspected has passed the quality inspection, otherwise not. The first minimum rectangular box and the first image difference description text loaded on the image pair displayed on part of the pages or all of the pages can be output, which is beneficial for quality inspectors to perform corresponding difference elimination processing in the subsequent printing process to ensure the quality of subsequent printed products.

[0087] Therefore, based on the multi-page printing quality inspection method described in the aforementioned steps S1 to S7, a new printing quality inspection and comparison scheme is provided, which can automatically locate the difference area and give the difference description in the multi-page printing quality inspection process, that is, after determining the one-to-one correspondence between the multi-page scanned images of the printed matter to be inspected and the multi-page reference images and graying them to obtain each pair of scanned grayscale images and reference grayscale images, for each pair of scanned images and reference images, firstly perform a pixel-level grayscale comparison to determine the corresponding minimum rectangular frame that contains all the pixels with inconsistent grayscale contrast, and when the area proportion of the corresponding minimum rectangular frame is less than or equal to When the ratio threshold is preset, the corresponding scanned sub-image and the reference sub-image surrounded by the minimum rectangular frame are cut out from the corresponding image pair. Finally, the image difference description generation model should output the corresponding image difference description text, and load the display minimum rectangular frame and the image difference description text on the corresponding image pair. In this way, the difference area can be automatically located and the difference description can be given during the multi-page printing quality inspection process, which greatly improves the quality inspection efficiency and avoids human errors. It is then beneficial to carry out the corresponding difference elimination processing in the subsequent printing process to ensure the quality of subsequent printed products and facilitate practical application and promotion.

[0088] Based on the technical solution of the first aspect mentioned above, this embodiment also provides a possible design of how to further finely locate the difference area and give the corresponding difference description content, that is, after determining the corresponding first minimum rectangular frame within any grayscale image for each pair of scanned images and reference images, the method also includes but is not limited to the following steps S81 to S86.

[0089] S81. For a pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, if the area ratio of the corresponding first minimum rectangular frame in any corresponding grayscale image is greater than a preset second ratio threshold, then the corresponding scanned grayscale sub-image and reference grayscale sub-image surrounded by the corresponding first minimum rectangular frame are cut out from the corresponding grayscale image pair, wherein the second ratio threshold is greater than the first ratio threshold.

[0090] In the step S81, the second ratio threshold is used as a criterion for determining whether to further fine-tune the location of the difference region, and may be 10% for example.

[0091] S82. Perform gridding processing on the scanned grayscale sub-image and the reference grayscale sub-image respectively to obtain a plurality of scanned grayscale sub-images and a plurality of reference grayscale sub-images corresponding to the plurality of scanned grayscale sub-images one by one.

[0092] In the step S82, the scanned grayscale sub-image refers to a sub-image of the scanned grayscale sub-image, and the reference grayscale sub-image refers to a sub-image of the reference grayscale sub-image; specifically, the scanned grayscale sub-image is subjected to gridding processing to obtain the multiple scanned grayscale sub-images; the reference grayscale sub-image is subjected to the gridding processing to obtain the multiple reference grayscale sub-images. In addition, the number of the multiple scanned grayscale sub-images or the multiple reference grayscale sub-images can be set in a positive correlation based on the ratio of the second ratio threshold to the first ratio threshold, that is, the larger the ratio is, the more the number of the multiple scanned grayscale sub-images or the multiple reference grayscale sub-images is set, so as to complete the further difference area positioning task in one step.

[0093] S83. For each pair of scanned grayscale images and reference grayscale images that have a mapping relationship among the multiple scanned grayscale images and the multiple reference grayscale images, determine a plurality of third pixel points in any corresponding grayscale image whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and compare the grayscale values ​​of each third pixel point in the multiple third pixel points in the corresponding grayscale image pair, and determine the corresponding fourth pixel point that does not have the grayscale value consistency characteristic in the corresponding grayscale image pair.

[0094] In the step S83, the any grayscale image is the scanned grayscale image or the reference grayscale image in each pair of the scanned grayscale image and the reference grayscale image. In addition, the specific determination details of the third pixel point and the fourth pixel point can be obtained by referring to the derivation of the aforementioned step S4, which will not be repeated here.

[0095] S84. For each pair of scanned grayscale grandson images and reference grayscale grandson images, if the number of corresponding fourth pixel points is non-zero, determine the corresponding second minimum rectangular frame within any of the grayscale grandson images based on all the corresponding fourth pixel points, wherein the second minimum rectangular frame refers to a rectangular frame with the smallest area that is used to enclose all the corresponding fourth pixel points.

[0096] In the step S84, the specific details of determining the second minimum rectangular frame can be referred to the aforementioned step S5, which will not be repeated here. In addition, for each pair of scanned grayscale grandchild images and reference grayscale grandchild images, if the number of the corresponding fourth pixel points is zero, there is no need to generate the corresponding second minimum rectangular frame (that is, there is no corresponding difference area).

[0097] S85. For each pair of scanned grayscale sub-images and reference grayscale sub-images, if the area ratio of the corresponding second minimum rectangular frame in any of the grayscale images is greater than a preset third ratio threshold, then the corresponding second scanned sub-image and second reference sub-image surrounded by the corresponding second minimum rectangular frame are cut out from the pair of scanned images and reference images.

[0098] In step S85, the second minimum rectangular frame is the difference area obtained by further fine positioning; the third ratio threshold is used as a criterion for measuring whether the difference area can be ignored in this comparison quality inspection process, that is, if the area of ​​the second minimum rectangular frame in any grayscale image is too small, the corresponding difference area can be ignored in this comparison quality inspection process, and vice versa. In addition, the third ratio threshold can be set in a negative correlation based on the ratio of the second ratio threshold to the first ratio threshold, that is, the larger the ratio is, the smaller the third ratio threshold needs to be set because the number of images of the multiple scanned grayscale grandson images or the multiple reference grayscale grandson images is more; and the third ratio threshold can also be equal to the first ratio threshold, that is, 5% for example.

[0099] S86. For each pair of scanned grayscale sub-images and reference grayscale sub-images, the corresponding second scanned sub-image and the second reference sub-image are imported into a pre-trained image difference description generation model, the corresponding second image difference description text is output, and the second minimum rectangular box and the second image difference description text are loaded and displayed on the pair of scanned images and reference images.

[0100] Due to the possible design one described in the aforementioned steps S81 to S86, when the initially located difference area is too large, the difference area can be further precisely located and corresponding difference description content can be given to improve the user experience.

[0101] like Figure 5 As shown, the second aspect of this embodiment provides a virtual device for implementing the multi-page printing quality inspection method described in the first aspect or possible design one, including an image file acquisition unit, a correspondence determination unit, a grayscale processing unit, a pixel grayscale comparison unit, a rectangular frame determination unit, a sub-image interception unit and a difference description generation unit;

[0102] The image file acquisition unit is used to acquire a scanned image file and a reference image file of the printed product to be inspected, wherein the printed product to be inspected is a multi-page printed product, the scanned image file contains multiple pages of scanned images, and the reference image file contains multiple pages of reference images;

[0103] The correspondence determination unit is communicatively connected to the image file acquisition unit, and is used to determine a one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and to make the scanned images and the corresponding reference images have the same resolution and size, the same size as the plate core, or a size that is scaled 1:1 in length and width;

[0104] The grayscale processing unit is communicatively connected to the corresponding relationship determining unit, and is used to perform grayscale processing on each pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, respectively, to obtain each pair of scanned grayscale images and reference grayscale images;

[0105] The pixel grayscale comparison unit is communicatively connected to the grayscale processing unit, and is used to determine, for each pair of scanned images and reference images, a plurality of first pixel points in any corresponding grayscale image whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and respectively compare the grayscale values ​​of each first pixel point in the corresponding grayscale image pair among the plurality of first pixel points, and determine a corresponding second pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale image pair;

[0106] The rectangular frame determination unit is communicatively connected to the pixel grayscale comparison unit, and is used for determining, for each pair of scanned images and reference images, that the total number of the corresponding second pixel points is equal to zero, that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, determining a first minimum rectangular frame corresponding to all the corresponding second pixel points and within any grayscale image, wherein the first minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding second pixel points;

[0107] The sub-image interception unit is communicatively connected to the image file acquisition unit and the rectangular frame determination unit, respectively, and is used for determining, for each pair of scanned images and reference images, that the printed product to be inspected has passed the quality inspection on the corresponding page if the area ratio of the corresponding first minimum rectangular frame in any grayscale image is less than or equal to a preset first ratio threshold, and otherwise, intercepting the corresponding first scanned sub-image and the first reference sub-image surrounded by the corresponding first minimum rectangular frame from the corresponding image pair;

[0108] The difference description generation unit is communicatively connected to the sub-image capture unit, and is used for importing the corresponding first scanned sub-image and the first reference sub-image into a pre-trained image difference description generation model for each pair of scanned images and reference images, outputting the corresponding first image difference description text, and loading and displaying the first minimum rectangular box and the first image difference description text on the corresponding image pair.

[0109] The working process, working details and technical effects of the aforementioned device provided in the second aspect of this embodiment can be referred to the multi-page printing quality inspection method described in the first aspect or possible design one, and will not be described in detail here.

[0110] like Figure 6 As shown, the third aspect of this embodiment provides a physical system for implementing the multi-page printing quality inspection method described in the first aspect or the possible design one, including a scanner, a processing device and a display;

[0111] The scanner is communicatively connected to the processing device, and is used to scan and obtain a scanned image file of the printed matter to be inspected, and transmit the scanned image file to the processing device;

[0112] The processing device is communicatively connected to the display, and is used to execute the multi-page printing quality inspection method as described in the first aspect or possible design one, and transmit the loading results obtained by loading on the scanned image and the reference image to the display;

[0113] The display is used to display the loading result.

[0114] In a possible design, the scanner adopts a sheet-fed scanner and is integrated with the processing device and the display. This can have the following advantages: (1) Economical, that is, large-format printed materials can be folded and trimmed to become small-page printed materials, and then scanned to obtain image files, making the equipment required for scanning cheaper; (2) It is particularly suitable for quality inspection and comparison of printed materials after folding and punching from rotary printing presses; (3) It can be moved to multiple workstations for quality inspection and comparison, that is, because the whole machine is small and convenient, it can be moved to the required workstation, bringing convenience; (4) It can solve the problem that existing equipment cannot achieve the purpose of a multi-functional all-in-one machine such as pre-press sample inspection, printing initial inspection, printing random inspection, and final inspection of the whole book and the documents provided by the customer before binding.

[0115] The working process, working details and technical effects of the aforementioned system provided in the third aspect of this embodiment can be referred to the multi-page printing quality inspection method described in the first aspect or possible design one, and will not be described in detail here.

[0116] like Figure 7 As shown, the fourth aspect of this embodiment provides a computer device for executing the multi-page printing quality inspection method as described in the first aspect or possible design one, including a memory, a processor and a transceiver that are sequentially connected in communication, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program to execute the multi-page printing quality inspection method as described in the first aspect or possible design one. For example, the memory may include, but is not limited to, a random access memory (Random-Access Memory, RAM), a read-only memory (Read-Only Memory, ROM), a flash memory (Flash Memory), a first-in-first-out memory (First Input First Output, FIFO) and / or a first-in-last-out memory (First Input Last Output, FILO), etc.; the processor may include, but is not limited to, a microprocessor of the STM32F105 series. In addition, the computer device may also include, but is not limited to, a power module, a display screen and other necessary components.

[0117] The working process, working details and technical effects of the aforementioned computer equipment provided in the fourth aspect of this embodiment can be found in the multi-page printing quality inspection method described in the first aspect or possible design one, and will not be described in detail here.

[0118] In a fifth aspect of this embodiment, there is provided a computer-readable storage medium storing instructions for the multi-page printed quality inspection method as described in the first aspect or possible design 1, that is, the computer-readable storage medium stores instructions, and when the instructions are run on a computer, the multi-page printed quality inspection method as described in the first aspect or possible design 1 is executed. The computer-readable storage medium refers to a carrier for storing data, which may include but is not limited to computer-readable storage media such as floppy disks, optical disks, hard disks, flash memories, USB flash drives, and / or memory sticks, and the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.

[0119] The working process, working details and technical effects of the aforementioned computer-readable storage medium provided in the fifth aspect of this embodiment can be referred to the multi-page printing quality inspection method described in the first aspect or possible design one, and will not be repeated here.

[0120] A sixth aspect of the present embodiment provides a computer program product, including a computer program or instructions, wherein the computer program or instructions, when executed by a computer, implements the multi-page printing quality inspection method as described in the first aspect or possible design 1. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0121] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A multi-page printing quality inspection method, characterized in that: include: Acquire a scanned image file and a reference image file of a printed product to be inspected, wherein the printed product to be inspected is a multi-page printed product, the scanned image file contains multiple pages of scanned images, and the reference image file contains multiple pages of reference images; Determine a one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and make the scanned images and the corresponding reference images have the same resolution and size, the same size as the plate core, or a size that is scaled 1:1 in length and width; Performing grayscale processing on each pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, respectively, to obtain each pair of scanned grayscale images and reference grayscale images; For each pair of scanned images and reference images, a plurality of first pixel points whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale image are determined according to a preset grayscale threshold interval, and the grayscale values ​​of each first pixel point in the plurality of first pixel points in the corresponding grayscale image pair are respectively compared to determine a corresponding second pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale image pair; For each pair of scanned images and reference images, if the total number of the corresponding second pixel points is equal to zero, it is determined that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, a first minimum rectangular frame corresponding to all the corresponding second pixel points and within any one of the grayscale images is determined, wherein the first minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding second pixel points; For each pair of scanned images and reference images, if the area ratio of the corresponding first minimum rectangular frame in any grayscale image is less than or equal to a preset first ratio threshold, it is determined that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, a corresponding first scanned sub-image and a first reference sub-image enclosed by the corresponding first minimum rectangular frame are obtained from the corresponding image pair; For each pair of scanned images and reference images, the corresponding first scanned sub-image and the first reference sub-image are imported into a pre-trained image difference description generation model, the corresponding first image difference description text is output, and the first minimum rectangular box and the first image difference description text are loaded and displayed on the corresponding image pair.

2. The multi-page printing quality inspection method according to claim 1, characterized in that: When the printed matter to be inspected is a multi-page printed matter for the first inspection, the scanned image file is a multi-page scanned image file of the multi-page printed matter for the first inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of the large-format printed matter after multi-page imposition, and the reference image file is a multi-page electronic image file corresponding to the multi-page printed matter for the first inspection or a large-format electronic image file after multi-page imposition; Alternatively, when the printed matter to be inspected is a multi-page printed matter for random inspection, the scanned image file is a multi-page scanned image file of the multi-page printed matter for random inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of the large-format printed matter after multi-page imposition, and the reference image file is a multi-page scanned image file of the multi-page printed matter confirmed to be correct in the first inspection, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by double-sided scanning after folding, cutting and trimming of the large-format printed matter after multi-page imposition; Alternatively, when the printed matter to be inspected is a first multi-page printed matter, the scanned image file is a multi-page scanned image file of the first multi-page printed matter, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by folding, cutting, and trimming the large-format printed matter after multi-page imposition through double-sided scanning; the reference image file is a multi-page scanned image file of the second multi-page printed matter, a large-format scanned image file after multi-page imposition, or a scanned image file obtained by folding, cutting, and trimming the large-format printed matter after multi-page imposition through double-sided scanning, wherein the first multi-page printed matter and the second multi-page printed matter are different printed matters.

3. The multi-page printing quality inspection method according to claim 1, characterized in that: For each pair of scanned images and reference images, determining a plurality of first pixel points in any corresponding grayscale image and having grayscale values ​​belonging to the grayscale threshold interval according to a preset grayscale threshold interval, including: For each pair of scanned images and reference images, a plurality of first pixel points in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval are determined according to a preset grayscale threshold interval, and it is determined whether the total number of the plurality of first pixel points is lower than a preset first pixel point number threshold, and if so, the grayscale threshold interval is adjusted and updated, and then a plurality of first pixel points in any grayscale image and whose grayscale values ​​belong to a new grayscale threshold interval are determined again according to the new grayscale threshold interval, until it is determined that the total number of the plurality of first pixel points is greater than or equal to the first pixel point number threshold; And / or, for each pair of scanned images and reference images, determine a plurality of first pixel points in any corresponding grayscale image and whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and determine whether the total number of the plurality of first pixel points is higher than a preset second pixel number threshold; if so, adjust and update the grayscale threshold interval, and then determine a plurality of first pixel points in any grayscale image and whose grayscale values ​​belong to the new grayscale threshold interval according to the new grayscale threshold interval, until it is determined that the total number of the plurality of first pixel points is less than or equal to the second pixel number threshold.

4. The multi-page printing quality inspection method according to claim 1, characterized in that: For each pair of scanned images and reference images, determining a plurality of first pixel points in any corresponding grayscale image and having grayscale values ​​belonging to the grayscale threshold interval according to a preset grayscale threshold interval, including: For each pair of scanned images and reference images, a plurality of first pixel points whose grayscale values ​​belong to a preset grayscale threshold interval in any corresponding grayscale image are determined, and any grayscale image is gridded into a plurality of image sub-regions of the same size, and then the number of the first pixel points in each of the plurality of image sub-regions and the number standard deviation of the plurality of image sub-regions are obtained by statistics, and finally, it is determined whether the number standard deviation is higher than a preset standard deviation threshold, and if so, the grayscale threshold interval is adjusted and updated, and then a plurality of first pixel points whose grayscale values ​​belong to a new grayscale threshold interval in any grayscale image are determined again according to the new grayscale threshold interval, until it is determined that the number standard deviation is less than or equal to the standard deviation threshold.

5. The multi-page printing quality inspection method according to claim 1, characterized in that: After determining the first minimum rectangular frame of each pair of the scanned image and the reference image and within any one of the grayscale images, the method further includes: For a pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, if the area ratio of the corresponding first minimum rectangular frame in any corresponding grayscale image is greater than a preset second ratio threshold, a corresponding scanned grayscale sub-image and a reference grayscale sub-image surrounded by the corresponding first minimum rectangular frame are intercepted from the corresponding grayscale image pair, wherein the second ratio threshold is greater than the first ratio threshold; Performing gridding processing on the scanned grayscale sub-image and the reference grayscale sub-image respectively, to obtain a plurality of scanned grayscale sub-images and a plurality of reference grayscale sub-images corresponding to the plurality of scanned grayscale sub-images one by one; For each pair of scanned grayscale grandson images and reference grayscale grandson images that have a mapping relationship among the multiple scanned grayscale grandson images and the multiple reference grayscale grandson images, determine a plurality of third pixel points whose grayscale values ​​belong to the grayscale threshold interval in any corresponding grayscale grandson image according to a preset grayscale threshold interval, and respectively compare the grayscale values ​​of each third pixel point in the corresponding grayscale grandson image pair among the multiple third pixel points to determine a corresponding fourth pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale grandson image pair; For each pair of the scanned grayscale grandson images and the reference grayscale grandson images, if the number of the corresponding fourth pixel points is non-zero, determining a corresponding second minimum rectangular frame within any of the grayscale grandson images according to all the corresponding fourth pixel points, wherein the second minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding fourth pixel points; For each pair of scanned grayscale sub-images and reference grayscale sub-images, if the area ratio of the corresponding second minimum rectangular frame in any grayscale image is greater than a preset third ratio threshold, a corresponding second scanned sub-image and a second reference sub-image enclosed by the corresponding second minimum rectangular frame are obtained from the pair of scanned images and reference images; For each pair of scanned grayscale sub-images and reference grayscale sub-images, the corresponding second scanned sub-image and the second reference sub-image are imported into a pre-trained image difference description generation model, and the corresponding second image difference description text is output, and the second minimum rectangular box and the second image difference description text are loaded and displayed on the pair of scanned images and reference images.

6. A multi-page printing quality inspection device, characterized in that: It includes an image file acquisition unit, a corresponding relationship determination unit, a grayscale processing unit, a pixel grayscale comparison unit, a rectangular frame determination unit, a sub-image interception unit and a difference description generation unit; The image file acquisition unit is used to acquire a scanned image file and a reference image file of the printed product to be inspected, wherein the printed product to be inspected is a multi-page printed product, the scanned image file contains multiple pages of scanned images, and the reference image file contains multiple pages of reference images; The correspondence determination unit is communicatively connected to the image file acquisition unit, and is used to determine a one-to-one correspondence between the multiple pages of scanned images and the multiple pages of reference images, and to make the scanned images and the corresponding reference images have the same resolution and size, the same size as the plate core, or a size that is scaled 1:1 in length and width; The grayscale processing unit is communicatively connected to the corresponding relationship determining unit, and is used to perform grayscale processing on each pair of scanned images and reference images in the scanned image file and the reference image file and having a mapping relationship, respectively, to obtain each pair of scanned grayscale images and reference grayscale images; The pixel grayscale comparison unit is communicatively connected to the grayscale processing unit, and is used to determine, for each pair of scanned images and reference images, a plurality of first pixel points in any corresponding grayscale image whose grayscale values ​​belong to the grayscale threshold interval according to a preset grayscale threshold interval, and respectively compare the grayscale values ​​of each first pixel point in the corresponding grayscale image pair among the plurality of first pixel points, and determine a corresponding second pixel point that does not have a grayscale value consistency characteristic in the corresponding grayscale image pair; The rectangular frame determination unit is communicatively connected to the pixel grayscale comparison unit, and is used for determining, for each pair of scanned images and reference images, that the total number of the corresponding second pixel points is equal to zero, that the printed product to be inspected has passed the quality inspection on the corresponding page; otherwise, determining a first minimum rectangular frame corresponding to all the corresponding second pixel points and within any grayscale image, wherein the first minimum rectangular frame refers to a rectangular frame with a minimum area that is used to surround all the corresponding second pixel points; The sub-image interception unit is communicatively connected to the image file acquisition unit and the rectangular frame determination unit, respectively, and is used for determining, for each pair of scanned images and reference images, that the printed product to be inspected has passed the quality inspection on the corresponding page if the area ratio of the corresponding first minimum rectangular frame in any grayscale image is less than or equal to a preset first ratio threshold, and otherwise, intercepting the corresponding first scanned sub-image and the first reference sub-image surrounded by the corresponding first minimum rectangular frame from the corresponding image pair; The difference description generation unit is communicatively connected to the sub-image capture unit, and is used for importing the corresponding first scanned sub-image and the first reference sub-image into a pre-trained image difference description generation model for each pair of scanned images and reference images, outputting the corresponding first image difference description text, and loading and displaying the first minimum rectangular box and the first image difference description text on the corresponding image pair.

7. A multi-page printing quality inspection system, characterized in that: Includes scanners, processing equipment and displays; The scanner is communicatively connected to the processing device, and is used to scan and obtain a scanned image file of the printed matter to be inspected, and transmit the scanned image file to the processing device; The processing device is communicatively connected to the display, and is used to execute the multi-page printing quality inspection method according to any one of claims 1 to 5, and transmit the loading results obtained by loading on the scanned image and the reference image to the display; The display is used to display the loading result.

8. A computer device, characterized in that: It includes a memory, a processor and a transceiver which are communicatively connected in sequence, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program to execute the multi-page printing quality inspection method as described in any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that The computer-readable storage medium stores instructions, and when the instructions are executed on the computer, the multi-page printing quality inspection method as described in any one of claims 1 to 5 is executed.

10. A computer program product comprising a computer program or instructions, characterized in that When the computer program or the instruction is executed by a computer, the multi-page printing quality inspection method according to any one of claims 1 to 5 is implemented.

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