Invisible 2D dot matrix code that can be spliced, cut, and fully embedded

Abstract

This invention discloses a method for embedding a hidden two-dimensional dot matrix watermark using a splicable, cut-out, and fully embedded method. It includes: (1) data normalization encoding; (2) data information signature; (3) multiple error detection and correction encoding; (4) two-dimensional dot matrix; (5) pseudo-random scrambling of the dot matrix data; (6) scale matching with the associated carrier image; (7) generation of a two-dimensional dot matrix point cloud; and (8) embedding the hidden two-dimensional dot matrix point cloud into the associated carrier image. This invention is an information hiding method based on the combination of reliability encoding and printed image processing in modern communication technology using two-dimensional coded dot matrices. It can hide anti-counterfeiting marks, images, or text within printed images to achieve information anti-counterfeiting and information traceability. This method improves the anti-attack capability of the two-dimensional dot matrix and overcomes the problem of unreadable information caused by image damage or misjudgment during printing and optical image acquisition.

Description

Technical Field

[0001] This invention relates to the field of printing anti-counterfeiting, specifically a method for encoding invisible two-dimensional dot matrix watermarks that can be spliced, cut, and fully embedded. Background Technology

[0002] With the rapid development of society, economy, and technology, consumers and merchants are increasingly aware of the importance of anti-counterfeiting. To achieve anti-counterfeiting functions for various products, the printing industry has undergone a large-scale technological revolution in recent years, such as the combined use of multiple printing equipment and the mutual integration of various printing processes, including multi-color overprinting, microprinting, latent image printing, invisible images, and image mixing printing. However, with the continuous improvement of printing technology, various counterfeiting methods have also emerged, causing market chaos and making effective anti-counterfeiting difficult. Therefore, this invention proposes an anti-counterfeiting technology based on a splicable, cut-out, and fully embedded invisible two-dimensional dot matrix watermark encoding method.

[0003] The seamless, fully embedded, two-dimensional dot matrix code is a highly reliable, copy-resistant, and stain-resistant printing anti-counterfeiting technology. It combines information technology with printing anti-counterfeiting technology, utilizing modern information technology and printing dot attributes to hide image information, thereby transmitting confidential information and achieving effective anti-counterfeiting. Given that printed images are typically halftone, halftone information hiding technology is widely used in printing and packaging anti-counterfeiting. Halftone halftone plays a significant role in pre-press image processing. This technology leverages the low-pass characteristic of the human eye—that is, when viewed from a certain distance, the human eye perceives close areas in an image space as a whole. Utilizing this characteristic, the local average grayscale of the halftone image observed by the human eye approximates the local average grayscale of the original image, presenting an overall continuous tone effect, thus achieving the purpose of anti-counterfeiting in printed materials.

[0004] However, the two-dimensional dot matrix anti-counterfeiting technology is susceptible to information damage caused by printing equipment and optical image acquisition equipment, making it impossible to extract effective hidden information. Therefore, it is necessary to use reliable coding technology with strong error detection and correction capabilities to solve the bit errors caused by various reasons. Summary of the Invention

[0005] The purpose of this invention is to provide a highly reliable encoding method that enables the generation of reliable, invisible printed anti-counterfeiting images or labels that are resistant to duplication, attack, and contamination.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows:

[0007] (1) Data normalization coding

[0008] Different formats and data, such as anti-counterfeiting labels, traceability service information, and value-added service information, are standardized and encoded to generate binary code stream data with detectable and error-correctable codes.

[0009] (2) Data information signature

[0010] The normalized encoded data generated in step (1) is processed according to the digital signature algorithm to generate a unique authentication signature, and the signature is arranged in the form of binary code stream data after the normalized encoded data to form secret information;

[0011] (3) Multiple error detection and correction coding

[0012] The secret information generated in step (2) is subjected to multiple error detection and correction coding, including linear block code coding, nonlinear block code coding, and interleaving coding.

[0013] (4) Two-dimensional coded dot matrix

[0014] The binary code stream generated by the multiple combination error detection and correction coding in step (3) is transformed by serial-to-parallel conversion and padded with 0 and 1 to generate a two-dimensional dot matrix;

[0015] (5) Pseudo-random scrambling of dot matrix data

[0016] The data generated in step (4) is pseudo-randomized according to different mathematical models, so that the distribution ratio of the rows, columns and their own 0 bits (or 1 bits) of the dot matrix is ​​close to 50%, and the two-dimensional dot matrix presents a randomized and uniformly distributed two-dimensional dot matrix in the two-dimensional space.

[0017] (6) Scale matching of associated carrier images

[0018] Based on the physical parameters of the carrier image, the two-dimensional dot matrix generated in step (5) is scale-matched with the physical parameters to obtain the corresponding copying and splicing parameters.

[0019] (7) Generate a two-dimensional point cloud map

[0020] Combining the two-dimensional dot matrix in step (5) and the copying and splicing parameters in step (6), a two-dimensional dot matrix point cloud map with physical parameters consistent with the carrier image is generated according to the spatial mapping model.

[0021] (8) Implanting a hidden two-dimensional dot matrix point cloud image into a related carrier image

[0022] The point cloud image generated in step (7) is loaded onto the carrier image using a gray-scale difference association algorithm to generate a reliable and invisible watermark image that is resistant to copying, attack, and contamination and is indistinguishable to the human eye.

[0023] (9) Output of invisible two-dimensional dot matrix anti-counterfeiting images.

[0024] The invisible image generated in step (8) is output onto a medium by printing or printing. Printing media include paper, plastic film, metal materials, etc. Printing methods include inkjet printing, laser printing, screen printing, thermal transfer, etc. Printing inks can include ordinary inks, water-based inks, UV inks, and invisible inks.

[0025] As an improvement to the above technical solution, the data normalization processing object in step (1) includes normalizing and encoding video, image, URL, text, item serial number, etc., to obtain a normalized binary code stream.

[0026] As an improvement to the above technical solution, the information signature in step (2) includes generating a specific bit of authentication signature information by digesting the binary code stream data according to the RSA digital signature algorithm, Hash signature algorithm, SHA series algorithm or DSA digital signature algorithm, and recombining it with the binary code stream data to obtain secret information.

[0027] As an improvement to the above technical solution, the linear block code (BCH, RS, CRC, LDPC) encoding, nonlinear block code encoding (convolutional code, TURBO code) and interleaving encoding described in step (3) are multiple error detection and correction codes.

[0028] As an improvement to the above technical solution, the 0 and 1 padding in step (4) refers to padding the empty bits of binary information when the binary code stream is converted from serial to parallel. This padding method can use pseudo-random 0 and 1 sequences, all 0s or all 1s, and the local coding sequence obtained in step (3) to pad the empty bits.

[0029] As an improvement to the above technical solution, the mathematical model in step (5) refers to generating a randomized and uniformly distributed two-dimensional dot matrix by performing XOR operations on the corresponding masks of the two-dimensional dot matrix according to different mathematical formulas.

[0030] As an improvement to the above technical solution, the scale matching of the associated carrier image in step (6) refers to matching the scale of the two-dimensional dot matrix with the physical parameters of the carrier image to obtain the corresponding copying and splicing parameters.

[0031] As an improvement to the above technical solution, the two-dimensional dot matrix cloud map mentioned in step (7) refers to a two-dimensional dot matrix cloud map whose physical parameters are consistent with the carrier image, generated by combining the two-dimensional dot matrix in step (5) and the copying and splicing parameters in step (6) according to the spatial mapping model.

[0032] As an improvement to the above technical solution, the implantation algorithm in step (8) refers to using a pixel difference algorithm to load the pixel grayscale of the carrier image and the pixel distribution of the point cloud image onto the carrier image to generate a reliable and invisible watermark image with anti-copying, anti-attack, and anti-fouling functions that is indistinguishable to the human eye.

[0033] As an improvement to the above technical solution, step (9) of outputting the invisible two-dimensional dot matrix anti-counterfeiting image can be done by printing or other methods onto a medium. Printing media include paper media, plastic film media, metal materials, etc. Printing methods include inkjet printing, laser printing, screen printing, thermal transfer, and other printing processes. Printing inks can include ordinary inks, water-based inks, UV inks, and invisible inks.

[0034] As an improvement to the above technical solution, the carrier image includes a continuous tone monochrome image, a continuous tone color image, a halftone monochrome image, and a halftone color image.

[0035] The beneficial effects of this invention are as follows:

[0036] This invention is an anti-counterfeiting two-dimensional dot matrix that can be hidden in trademarks and printed images. It involves standardizing and encoding the original data to be hidden, performing error-correcting encoding on the signature digest information, and then processing it in serial and parallel pairs with different mathematical model masks to generate two-dimensional dot matrix data. The two-dimensional dot matrix is ​​then copied and spliced ​​according to the physical parameters of the carrier image. The expanded two-dimensional dot matrix is ​​then spatially mapped and embedded into the carrier image to generate a printed anti-counterfeiting image. This method improves information recording capabilities, provides fast information reading speed and high effectiveness, and avoids information security leaks caused by damage or copying of the anti-counterfeiting image. Attached Figure Description

[0037] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0038] Appendix Figure 1 This is a schematic diagram of the invisible two-dimensional dot matrix encoding process of the present invention, which can be spliced, cut, and fully covered. Detailed Implementation

[0039] To address the security issues and practical application needs of anti-counterfeiting in printed materials, this method uses modern communication technology and printing image processing technology to embed hidden secret information into printed materials in the form of a two-dimensional dot matrix, thereby obtaining an anti-counterfeiting, invisible two-dimensional dot matrix image that is resistant to copying.

[0040] Example 1

[0041] Example 1

[0042] A coding method for anti-counterfeiting trademarks and other items, primarily applied to digital printing on paper media. (See attached document.) Figure 1 The method includes the following steps:

[0043] (1) Data normalization coding

[0044] Different formats and data, such as anti-counterfeiting labels, traceability service information, and value-added service information, are standardized and encoded to generate binary code stream data with detectable and error-correctable codes.

[0045] (2) Data information signature

[0046] The normalized encoded data generated in step (1) is processed according to the digital signature algorithm to generate a unique authentication signature, and the signature is arranged in the form of binary code stream data after the normalized encoded data to form secret information;

[0047] (3) Multiple error detection and correction coding

[0048] The secret information generated in step (2) is subjected to multiple error detection and correction coding, including linear block code coding, nonlinear block code coding, and interleaving coding.

[0049] (4) Two-dimensional coded dot matrix

[0050] The binary code stream generated by the multiple combination error detection and correction coding in step (3) is transformed by serial-to-parallel conversion and padded with 0 and 1 to generate a two-dimensional dot matrix;

[0051] (5) Pseudo-random scrambling of dot matrix data

[0052] The data generated in step (4) is pseudo-randomized according to different mathematical models, so that the distribution ratio of the rows, columns and their own 0 bits (or 1 bits) of the dot matrix is ​​close to 50%, and the two-dimensional dot matrix presents a randomized and uniformly distributed two-dimensional dot matrix in the two-dimensional space.

[0053] (6) Scale matching of associated carrier images

[0054] Based on the physical parameters of the carrier image, the two-dimensional dot matrix generated in step (5) is scale-matched with the physical parameters to obtain the corresponding copying and splicing parameters.

[0055] (7) Generate a two-dimensional point cloud map

[0056] Combining the two-dimensional dot matrix in step (5) and the copying and splicing parameters in step (6), a two-dimensional dot matrix point cloud map with physical parameters consistent with the carrier image is generated according to the spatial mapping model.

[0057] (8) Implanting a hidden two-dimensional dot matrix point cloud image into a related carrier image

[0058] The point cloud image generated in step (7) is loaded onto the carrier image using a grayscale difference association algorithm or digital latent image technology to generate a reliable and invisible watermark image that is resistant to copying, attack, and contamination.

[0059] (9) Output of invisible two-dimensional dot matrix anti-counterfeiting images.

[0060] The invisible image generated in step (8) is output onto a paper medium by printing. The printing medium includes paper, plastic film, metal, and other media. Printing methods include inkjet printing, laser printing, screen printing, and thermal transfer. Printing inks can include ordinary inks, water-based inks, UV inks, and invisible inks.

[0061] Example 2

[0062] A coding method for anti-counterfeiting packaging images printed using digital printing, primarily applied to plastic film media.

[0063] Steps (1) to (9) of this method are the same as in Example 1. Step (9) prints the anti-counterfeiting image onto a plastic film medium. The printing medium includes paper, plastic film, metal, and other media. The printing methods include inkjet printing, laser printing, screen printing, thermal transfer, and other printing processes. The printing inks can be ordinary inks, water-based inks, UV inks, and invisible inks.

[0064] Example 3

[0065] A coding method for anti-counterfeiting labels, certificates, tickets, and securities printed primarily using digital printing with invisible ink.

[0066] Steps (1) to (9) of this method are the same as in Example 1. Step (9) prints the anti-counterfeiting image onto various media using invisible ink printing materials. The printing media include paper, plastic film, metal, and other media. The printing methods include inkjet printing, laser printing, screen printing, thermal transfer, and other printing processes. The printing inks can be ordinary inks, water-based inks, UV inks, and invisible inks.

[0067] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for watermarking encoding of a two-dimensional dot-matrix code, which is a cut-and-seamable full-paving implant, characterized in that: The method realizes reliable information hiding by using modern communication technology and pre-press image processing technology, and generates a splicable and cuttable two-dimensional dot matrix image through error detection and correction coding processing of secret information after scrambling of data information with hidden data in different formats and signature information thereof. (1) Data normalization coding The different formats and data of anti-counterfeit identification, traceability service information and value-added service information are normalized and coded to generate binary code stream data that can be checked and corrected. (2) Data information signature The normalized coded data generated in step (1) is processed according to a digital signature algorithm to generate a unique authentication signature, and the signature is arranged in the form of binary code stream data after the normalized coded data to form secret information. (3) Multiple error detection and correction coding The secret information generated in step (2) is subjected to linear block code coding, nonlinear block code coding and interleaving coding multiple error detection and correction coding. (4) Two-dimensional coding dot matrix The binary code stream generated by the multiple combination error detection and correction coding in step (3) is subjected to serial-parallel conversion and 0 and 1 complement bit generation to generate a two-dimensional dot matrix. (5) Pseudo-random scrambling of dot matrix data The data generated in step (4) is subjected to pseudo-random scrambling according to different mathematical models, so that the distribution ratio of rows, columns and their own 0 bits or 1 bits of the dot matrix is close to 50%, and the two-dimensional dot matrix presents randomization and uniform distribution in two-dimensional space. (6) Scale matching with associated carrier image The two-dimensional dot matrix generated in step (5) is subjected to scale matching with the physical parameters of the carrier image to obtain corresponding replication and splicing parameters. (7) Generation of two-dimensional dot matrix point cloud image The two-dimensional dot matrix point cloud image with physical parameters consistent with the carrier image is generated according to the space mapping model in combination with the two-dimensional dot matrix of step (5) and the replication and splicing parameters of step (6). (8) Implantation of invisible two-dimensional dot matrix point cloud image into associated carrier image The point cloud image generated in step (7) is loaded onto the carrier image using a gray difference correlation algorithm to generate an invisible watermark image with reliable anti-copy, anti-attack and anti-damage functions and invisible to the human eye. (9) Output of invisible two-dimensional dot matrix anti-counterfeit image The invisible image generated in step (8) is output on a medium by printing or printing.

2. The invisible two-dimensional dot matrix watermark encoding method according to claim 1, characterized in that: The data normalization coding processing object in step (1) includes video, image, website, text and a series of data information compiled by a computer.

3. The method of claim 2, wherein: The corresponding binary code stream is obtained through the specified coding method.

4. The method of claim 1, wherein the method further comprises: generating a plurality of two-dimensional point array codes; and embedding the plurality of two-dimensional point array codes in the image. The data information signature in step (2) includes authentication signature information with a specific bit generated after digesting the binary code stream data in step (1) according to RSA digital signature algorithm, Hash signature algorithm, SHA series algorithm or DSA digital signature algorithm, and the secret information is obtained by recombining the binary code stream data in step (1).

5. The invisible two-dimensional dot matrix watermark encoding method according to claim 4, characterized in that: The multiple error detection and correction coding in step (3) is based on the conversion between binary code stream data and binary code stream data, including synchronization information scattering coding, secret information nonlinear block coding, complement bit information linear block coding and overall information interleaving coding.

6. The method of claim 1 or 5, wherein: The pseudo-random scrambling of the dot matrix data in step (5) refers to scrambling the two-dimensional dot matrix in step (4) according to different mathematical models, and performing splicing under the same physical parameters, while making the proportion of 0 bits and 1 bits of the two-dimensional dot matrix close to 50%.

7. The invisible two-dimensional dot matrix watermark encoding method according to claim 1, characterized in that: The two-dimensional dot matrix is a single-pixel anti-counterfeiting dot matrix data in the spatial domain with a gray level of the second order.

8. The method of claim 1 or 5, wherein: The scale matching of the associated carrier image in step (6) refers to spatially periodically copying and splicing the two-dimensional dot matrix generated in step (5) according to the specific parameters of the carrier image, generating a two-dimensional dot matrix matching the scale of the carrier image, and generating a two-dimensional dot matrix point cloud graph through the spatial mapping model in step (7).

9. The method of claim 8, wherein the method further comprises: determining a number of the first and second watermarking patterns; and determining a number of the first and second watermarking patterns to be applied to the first and second watermarking patterns, respectively. The gray difference correlation algorithm in step (8) refers to correlating the 8-bit pixel values of each channel in the local area of the carrier image with the 1-bit pixel values of the corresponding two-dimensional dot matrix in the local area, and forming an invisible watermark image that cannot be distinguished by the human eye after threshold difference of the pixel values of the carrier image.

10. The method of claim 9, wherein the method further comprises: The image output mode in step (9) includes printing media including paper media, plastic film media, and metal material media; and printing methods including inkjet printing, laser printing, screen printing, and thermal transfer printing processes. The printing ink uses ordinary ink, water-based ink, UV ink, and invisible ink.

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