CN111177666A - Forensic document anti-counterfeiting and anti-tampering method and system based on fragile watermark - Google Patents
Forensic document anti-counterfeiting and anti-tampering method and system based on fragile watermark Download PDFInfo
- Publication number
- CN111177666A CN111177666A CN201911403328.7A CN201911403328A CN111177666A CN 111177666 A CN111177666 A CN 111177666A CN 201911403328 A CN201911403328 A CN 201911403328A CN 111177666 A CN111177666 A CN 111177666A
- Authority
- CN
- China
- Prior art keywords
- counterfeiting
- pdf document
- watermark
- tampering
- fingerprint information
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 75
- 238000012795 verification Methods 0.000 claims description 138
- 239000000284 extract Substances 0.000 claims description 6
- 238000010586 diagram Methods 0.000 description 8
- 238000004590 computer program Methods 0.000 description 7
- 230000006870 function Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
- G06F21/10—Protecting distributed programs or content, e.g. vending or licensing of copyrighted material ; Digital rights management [DRM]
- G06F21/16—Program or content traceability, e.g. by watermarking
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F21/00—Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
- G06F21/60—Protecting data
- G06F21/64—Protecting data integrity, e.g. using checksums, certificates or signatures
Landscapes
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Software Systems (AREA)
- Computer Security & Cryptography (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Physics & Mathematics (AREA)
- General Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Bioethics (AREA)
- Health & Medical Sciences (AREA)
- Multimedia (AREA)
- Technology Law (AREA)
- Editing Of Facsimile Originals (AREA)
- Image Processing (AREA)
Abstract
The invention relates to a judicial literature anti-counterfeiting and anti-tampering method and a system based on fragile watermarks.A hashed value of contents to be protected in a PDF document is obtained by calculation when the PDF document is generated, the hashed value is combined with characteristic element characters in the PDF document to generate anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document, the encrypted fingerprint information is used as a watermark to be added into a picture, and the picture added with the watermark is added into the PDF document; when the authenticity of the PDF document is verified, calculating to obtain a hash value of content to be protected in the PDF document to be verified, combining the hash value with characteristic element characters in the PDF document to be verified, generating anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document to be verified, then comparing the anti-counterfeiting and anti-tampering characteristic fingerprint information with anti-counterfeiting and anti-tampering characteristic fingerprint information obtained by decrypting watermarks in pictures in the PDF document to be verified, if the anti-counterfeiting and anti-tampering characteristic fingerprint information is consistent, the PDF document to be verified is true and not tampered, and if not, the PDF document to be verified is forged or tampered.
Description
Technical Field
The invention belongs to the technical field of information security, and particularly relates to a judicial literature anti-counterfeiting and anti-tampering method and system based on a fragile watermark.
Background
For some important electronic documents, such as electronic contracts and judicial papery electronic documents, it is important to prevent counterfeiting and tampering. At present, common technical schemes for anti-counterfeiting and anti-tampering of PDF documents comprise a digital signature technology based on a digital certificate and an electronic signature technology based on the digital certificate and the digital signature. Both the digital signature technology based on the digital certificate and the electronic signature technology need to use numbers, not only needs the support of a document reader, but also needs to apply, acquire and update the digital certificate, is relatively troublesome to apply, and belongs to a relatively 'heavy' technology.
Digital Watermark (Digital Watermark) is a technology for embedding information in pictures, and can be used for copyright protection and anti-counterfeiting of the pictures. Digital watermarks include fragile watermarks, semi-fragile watermarks and robust watermarks. So-called fragile watermarks, i.e. small changes to a picture can cause distortion of watermark information embedded in the picture and cannot be recovered, while semi-fragile watermarks can bear a certain degree of modification to the picture, while robust watermarks can bear a larger modification to the picture, such as compression. When a robust watermark is used to embed data, it often becomes a fragile watermark.
The invention aims to apply the watermarking technology to the anti-counterfeiting and anti-tampering of the PDF document.
Disclosure of Invention
In order to realize the aim of the invention, the technical scheme of the judicial document anti-counterfeiting and anti-tampering method and system based on the fragile watermark comprises a PDF document anti-counterfeiting and anti-tampering method based on the watermark, a PDF document anti-counterfeiting and anti-tampering verification method based on the watermark and a corresponding system based on the two methods, so as to realize the protection of the PDF document.
The invention solves the technical problems by the following technical means:
a PDF document false-proof tamper-proof watermark embedding method is characterized in that when a PDF document is generated, a PDF document generation system calls a watermark adding API to request generation and addition of false-proof tamper-proof watermarks; the request submitted by the PDF document generation system to the watermark adding API comprises a PDF document and a picture (such as a two-dimensional code, Logo, an electronic seal and the like) to be added with a watermark;
acquiring contents to be protected from a PDF document by a watermark adding API (according to convention or setting), and calculating to obtain a hash value of the contents to be protected;
the watermarking API extracts appointed or specified feature element characters (namely pre-appointed, appointed or set feature element character information such as author names, time, titles and the like) from the PDF document;
the watermark adding API combines the hash values of the characteristic element characters and the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
the watermark adding API encrypts the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
the watermark adding API adds the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information as a watermark to a picture, and then adds the picture (two-dimensional code, Logo, electronic seal and the like) added with the watermark to a PDF document;
the watermark adding API returns the PDF document added with the picture containing the watermark to a PDF document generating system for further processing and/or storage;
the Watermark refers to a Digital Watermark (Digital Watermark) embedded in a picture.
For the above PDF document anti-counterfeiting and anti-tampering watermark embedding method, the adopted digital watermark algorithm comprises a fragile watermark algorithm and a non-fragile watermark algorithm.
For the above-mentioned PDF document anti-counterfeiting and tamper-proof watermark embedding method, the content to be protected and the feature element text to be extracted in the PDF document are agreed, specified or set by the configuration information aiming at the watermark adding API.
For the above PDF document anti-counterfeiting and anti-tampering watermark embedding method, the encryption algorithm adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information is a symmetric key encryption algorithm or an asymmetric key encryption algorithm.
For the above-mentioned PDF document anti-counterfeiting and anti-tampering watermark embedding method, if an asymmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information, the public key (configured in the configuration information or in the cryptographic module) for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information is configured for the watermark adding API.
For the above PDF document anti-counterfeiting and anti-tampering watermark embedding method, if a symmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information, the symmetric keys adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same or different.
For the above PDF document anti-counterfeiting and anti-tampering watermark embedding method, if a symmetric key encryption algorithm is used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document, and the symmetric keys used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same, a symmetric key (for example, configured in a cryptographic module) for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents is configured for the watermark adding API.
For the above PDF document anti-counterfeiting and anti-tampering watermark embedding method, if a symmetric key encryption algorithm is used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document, and symmetric keys used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are different, a seed key is configured for the watermark adding API (for example, configured in a cryptographic module); when the anti-counterfeiting and anti-tampering feature fingerprint information of a PDF document is encrypted, the watermarking API or the cryptographic module called by the watermarking API generates a symmetric key for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document by using the seed key and the identification information of the PDF (such as the document identification information in the PDF document).
Based on the PDFPDF document anti-counterfeiting and anti-tampering watermark embedding method, a corresponding PDF document anti-counterfeiting and anti-tampering watermark embedding system can be constructed, and the system comprises a PDF document generation system and a watermark adding API; and the PDF document generation system and the watermark adding API generate the PDF document containing the anti-counterfeiting and anti-tampering watermark picture according to the anti-counterfeiting and anti-tampering watermark embedding method of the PDF document.
Aiming at the above PDF document anti-counterfeiting and anti-tampering watermark embedding method, the corresponding PDF document anti-counterfeiting and anti-tampering verification method provided by the invention comprises the following steps:
when a user needs to verify the authenticity of a PDF document, submitting the PDF document to a PDF document verification system;
the PDF document verification system calls a watermark verification API and submits a verification request to the watermark verification API; the verification request submitted to the watermark verification API comprises a PDF document to be verified and submitted by a user;
extracting an image added with an anti-counterfeiting and anti-tampering watermark from a PDF document to be verified by the watermark verification API, extracting the added watermark from the image, and extracting encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information from the watermark;
the watermark verification API decrypts the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information to obtain a plaintext of the anti-counterfeiting and anti-tampering characteristic fingerprint information contained in the watermark, namely a combination of characteristic element characters of the PDF document and a hash value of content to be protected when the watermark is added;
the watermark verification API extracts contents to be protected and characteristic element characters from the PDF document to be verified, and calculates a hash value of the contents to be protected extracted from the PDF document to be verified;
the watermark verification API combines the characteristic element characters obtained from the PDF document and the hash value of the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document to be verified;
the watermark verification API compares the anti-counterfeiting anti-tampering characteristic fingerprint information generated from the PDF document to be verified with the anti-counterfeiting anti-tampering characteristic fingerprint information acquired from the image watermark to determine whether the anti-counterfeiting anti-tampering characteristic fingerprint information is consistent with the anti-counterfeiting anti-tampering characteristic fingerprint information acquired from the image watermark, if so, the verification is passed, the success and the characteristic element characters of the PDF document are returned, and if not, the verification is not passed, and an error is returned;
the PDF document verification system returns a verification result to the user, wherein the verification result comprises passing or failing verification; and if the verification is passed, the PDF document verification system simultaneously displays the characteristic element characters of the PDF document to the user.
For the above PDF document anti-counterfeiting tamper-proof verification method, the watermark verification API has the same configuration information about the content of the PDF document to be protected and the feature element text to be extracted as the watermark addition API.
For the above PDF document anti-counterfeiting and anti-tampering verification method, if an asymmetric key algorithm is used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method, a private key (for example, configured in a cryptographic module) corresponding to the public key configured by the watermark adding API is configured for the watermark verification API, and is used for decrypting the encrypted anti-counterfeiting and anti-tampering feature fingerprint information.
For the above PDF document anti-counterfeiting and anti-tampering verification method, if the encryption of the anti-counterfeiting and anti-tampering feature fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method is a symmetric key encryption algorithm, and the symmetric keys used for the encryption of the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same, the symmetric key which is the same as the watermark adding API is configured for the watermark verification API, and is used for decrypting the encrypted anti-counterfeiting and anti-tampering feature fingerprint information.
For the above PDF document anti-counterfeiting and anti-tampering verification method, if the encryption of the anti-counterfeiting and anti-tampering feature fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method is a symmetric key encryption algorithm, and symmetric keys used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are different, a seed key that is the same as the watermark adding API is configured for the watermark verification API, and is used for generating a symmetric key required for decrypting the encrypted anti-counterfeiting and anti-tampering feature fingerprint information.
Based on the PDF document anti-counterfeiting and anti-tampering verification method, a corresponding PDF document anti-counterfeiting and anti-tampering verification system can be constructed, the system comprises a PDF document verification system and a watermark verification API, and when a user needs to verify the authenticity of a PDF document, the PDF document verification system and the watermark verification API verify the authenticity of the PDF document according to the PDF document anti-counterfeiting and anti-tampering verification method.
The invention has the beneficial effects that:
the judicial document anti-counterfeiting and anti-tampering method and system based on the fragile watermark provided by the invention comprise a PDF document anti-counterfeiting and anti-tampering method based on the watermark, a PDF document anti-counterfeiting and anti-tampering verification method based on the watermark and corresponding systems based on the two methods, so as to realize PDF document protection.
The digital watermark embedded into the picture in the PDF document based on the technical scheme of the watermark for anti-counterfeiting and anti-tampering of the PDF document not only can ensure the authenticity of protected contents and characteristic element characters in the PDF document, but also can discover any modification to the contents or information; therefore, the technical scheme of the invention can ensure the authenticity of the PDF document, effectively prevent the counterfeiting and the falsification of the PDF document, and is simpler and more convenient to implement compared with a digital certificate or an electronic signature technology.
Drawings
In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
FIG. 1 is a flow chart of a PDF document anti-counterfeiting and anti-tampering watermark embedding method provided by the invention;
FIG. 2 is a flowchart of a verification method of a PDF document-based anti-counterfeiting and anti-tampering watermark embedding method provided by the invention.
Detailed Description
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
In order to specifically understand the technical solutions provided by the present invention, the technical solutions of the present invention will be described and illustrated in detail in the following examples. It is apparent that the embodiments provided by the present invention are not limited to the specific details familiar to those skilled in the art. The following detailed description of the preferred embodiments of the invention is intended to provide further embodiments of the invention in addition to those described herein.
The present invention will be further described with reference to the following examples. The following examples do not represent all possible embodiments and are not intended to limit the invention.
The forensic document anti-counterfeiting and anti-tampering method and system based on the fragile watermark provided by the specific embodiment of the invention specifically comprise a watermark-based PDF document anti-counterfeiting and anti-tampering method, a watermark-based PDF document anti-counterfeiting and anti-tampering verification method and corresponding systems based on the two methods, the protection of the PDF document is realized from four directions, and the forensic document anti-counterfeiting and anti-tampering method based on the fragile watermark is solved.
The method for embedding the anti-counterfeiting and anti-tampering watermark in the PDF document is shown in FIG. 1:
s1, when generating PDF document, PDF document generating system calls watermark adding API, request to generate and add anti-counterfeiting and anti-tampering watermark; the PDF document generation system submits a request to the watermark adding API, wherein the request comprises a PDF document and a picture to be added with a watermark;
s2, acquiring the content to be protected from the PDF document by the watermarking API, and calculating to obtain the hash value of the content to be protected;
s3, extracting appointed or specified feature element characters from the PDF document by the watermarking API;
s4, the watermarking API combines the hash value of the characteristic element characters and the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
s5, encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document by adding the watermark into the API;
s6, adding the watermark to the API, adding the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information as a watermark to the picture, and then adding the picture added with the watermark to the PDF document;
s7, the watermark adding API returns the PDF document added with the picture containing the watermark to the PDF document generating system for further processing and/or storage;
the watermark refers to a digital watermark embedded in a picture.
The method for embedding the anti-counterfeiting and anti-tampering watermark in the PDF document is realized based on a digital watermark algorithm, wherein the digital watermark algorithm comprises a fragile watermark algorithm and a non-fragile watermark algorithm.
In step S1, the content to be protected and the feature element text to be extracted in the PDF document are stipulated, specified or set by the configuration information of the watermarking API.
In step S5, the encryption algorithm used to encrypt the anti-counterfeit and tamper-resistant characteristic fingerprint information is a symmetric key encryption algorithm or an asymmetric key encryption algorithm. If an asymmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information, a public key for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information is configured for adding the API aiming at the watermark. If the anti-counterfeiting and anti-tampering feature fingerprint information is encrypted by adopting a symmetric key encryption algorithm, the symmetric keys used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same or different.
If a symmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document, and the symmetric keys adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same, a symmetric key for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents is configured for the watermarking API.
If a symmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document, and the symmetric keys adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are different, configuring a seed key for the watermark adding API; when the anti-counterfeiting and anti-tampering feature fingerprint information of a PDF document is encrypted, the watermarking API or the cryptographic module called by the watermarking API generates a symmetric key for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document by using the seed key and the identification information of the PDF.
Based on the same invention concept, the invention also provides a PDF document anti-counterfeiting and anti-tampering watermark embedding system corresponding to the PDF document anti-counterfeiting and anti-tampering watermark embedding method, wherein the system comprises a PDF document generation system and a watermark adding API; and the PDF document generation system and the watermark adding API generate the PDF document containing the anti-counterfeiting and anti-tampering watermark picture according to the anti-counterfeiting and anti-tampering watermark embedding method of the PDF document.
In addition, for the above solution, a PDF document anti-counterfeiting and anti-tampering verification method based on a PDF document anti-counterfeiting and anti-tampering watermark embedding method is provided, as shown in fig. 2:
s101, when a user needs to verify the authenticity of a PDF document, submitting the PDF document to a PDF document verification system;
s102, the PDF document verification system calls a watermark verification API and submits a verification request to the watermark verification API; the verification request submitted to the watermark verification API comprises a PDF document to be verified and submitted by a user;
s103, extracting an image added with an anti-counterfeiting and anti-tampering watermark from a PDF document to be verified by the watermark verification API, extracting the added watermark from the image, and extracting encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information from the watermark;
s104, the watermark verification API decrypts the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information to obtain a plaintext of the anti-counterfeiting and anti-tampering characteristic fingerprint information contained in the watermark, namely a combination of characteristic element characters of the PDF document and a hash value of content to be protected when the watermark is added;
s105, the watermark verification API extracts contents to be protected and characteristic element characters from the PDF document to be verified, and calculates a hash value of the contents to be protected extracted from the PDF document to be verified;
s106, the watermark verification API combines the characteristic element characters obtained from the PDF document and the hash value of the content to be protected to be used as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document to be verified;
s107, the watermark verification API compares the anti-counterfeiting and anti-tampering characteristic fingerprint information generated from the PDF document to be verified with the anti-counterfeiting and anti-tampering characteristic fingerprint information acquired from the image watermark to determine whether the anti-counterfeiting and anti-tampering characteristic fingerprint information is consistent with the anti-counterfeiting and anti-tampering characteristic fingerprint information acquired from the image watermark, if the anti-counterfeiting and anti-tampering characteristic fingerprint information is consistent with the anti-counterfeiting and anti-tampering characteristic fingerprint information acquired from the image watermark, the verification is passed;
s108, the PDF document verification system returns a verification result to the user, wherein the verification result comprises passing or failing of verification; and if the verification is passed, the PDF document verification system simultaneously displays the characteristic element characters of the PDF document to the user.
The watermark verification API has the same configuration information about the content to be protected and the characteristic element characters to be extracted of the PDF document as the watermark adding API.
If an asymmetric key algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method, a private key corresponding to a public key configured by the watermark adding API is configured for the watermark verification API and is used for decrypting the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information.
If the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method is a symmetric key encryption algorithm, and the symmetric keys used for the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information of different PDF documents are the same, the symmetric key which is the same as the watermark adding API is configured for the watermark verification API and is used for decrypting the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information.
If the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method is a symmetric key encryption algorithm, and the symmetric keys adopted for the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information of different PDF documents are different, the same seed key as the watermark adding API is configured for the watermark verification API and is used for generating a symmetric key required for decrypting the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information.
Correspondingly, the PDF document anti-counterfeiting and anti-tampering verification system comprises the PDF document verification system and a watermark verification API, and when a user needs to verify the authenticity of the PDF document, the PDF document verification system and the watermark verification API verify the authenticity of the PDF document according to the PDF document anti-counterfeiting and anti-tampering verification method.
Examples 1,
This embodiment relates to adding a picture with an anti-counterfeiting and anti-tampering watermark embedded in a PDF document, which is described in detail below.
When generating a PDF document, the PDF document generation system calls a watermark adding API to request generation and addition of an anti-counterfeiting and anti-tampering watermark; the request submitted by the PDF document generation system to the watermark adding API comprises a PDF document and a picture (such as a two-dimensional code, Logo, an electronic seal and the like) to be added with a watermark;
acquiring contents to be protected from a PDF document by a watermark adding API (according to convention or setting), and calculating to obtain a hash value of the contents to be protected;
the watermarking API extracts appointed or specified feature element characters (namely pre-appointed, appointed or set feature element character information such as author names, time, titles and the like) from the PDF document;
the watermark adding API combines the hash values of the characteristic element characters and the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
the watermark adding API encrypts the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
the watermark adding API adds the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information as a watermark to a picture, and then adds the picture (two-dimensional code, Logo, electronic seal and the like) added with the watermark to a PDF document;
the watermark adding API returns the PDF document added with the picture containing the watermark to a PDF document generating system for further processing and/or storage;
the Watermark refers to a Digital Watermark (Digital Watermark) embedded in a picture.
The digital watermarking algorithms employed in this embodiment include fragile watermarking algorithms and non-fragile watermarking algorithms.
In this embodiment, the content to be protected and the feature element text to be extracted in the PDF document are stipulated, specified or set by the configuration information of the watermarking API.
In this embodiment, the encryption algorithm used for encrypting the anti-counterfeit and tamper-resistant characteristic fingerprint information is an asymmetric key encryption algorithm.
In this embodiment, the API is configured with a public key (configured in the configuration information or in the cryptographic module) for encrypting the anti-counterfeit and anti-tampering feature fingerprint information.
Examples 2,
The difference between this example and example 1 is that: the anti-counterfeiting and anti-tampering feature fingerprint information is encrypted by adopting a symmetric key encryption algorithm, and the symmetric keys used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same; the watermarking API is configured with a symmetric key (such as in a cryptographic module) for encrypting anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents.
Examples 3,
The difference between this example and examples 1 and 2 is that: the anti-counterfeiting and anti-tampering feature fingerprint information is encrypted by adopting a symmetric key encryption algorithm, and the anti-counterfeiting and anti-tampering feature fingerprint information for different PDF documents is encrypted by adopting different symmetric keys; configuring a seed key (such as in a cryptographic module) for the watermarking API; when the anti-counterfeiting and anti-tampering feature fingerprint information of a PDF document is encrypted, the watermarking API or the cryptographic module called by the watermarking API generates a symmetric key for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document by using the seed key and the identification information of the PDF (such as the document identification information in the PDF document).
Examples 4,
In this embodiment, the PDF document containing the anti-counterfeiting and anti-tampering picture generated in embodiment 1 is subjected to anti-counterfeiting and anti-tampering verification, which is specifically described below.
When a user needs to verify the authenticity of a PDF document, submitting the PDF document to a PDF document verification system;
the PDF document verification system calls a watermark verification API and submits a verification request to the watermark verification API; the verification request submitted to the watermark verification API comprises a PDF document to be verified and submitted by a user;
extracting an image added with an anti-counterfeiting and anti-tampering watermark from a PDF document to be verified by the watermark verification API, extracting the added watermark from the image, and extracting encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information from the watermark;
the watermark verification API decrypts the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information to obtain a plaintext of the anti-counterfeiting and anti-tampering characteristic fingerprint information contained in the watermark, namely a combination of characteristic element characters of the PDF document and a hash value of content to be protected when the watermark is added;
the watermark verification API extracts contents to be protected and characteristic element characters from the PDF document to be verified, and calculates a hash value of the contents to be protected extracted from the PDF document to be verified;
the watermark verification API combines the characteristic element characters obtained from the PDF document and the hash value of the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document to be verified;
the watermark verification API compares the anti-counterfeiting anti-tampering characteristic fingerprint information generated from the PDF document to be verified with the anti-counterfeiting anti-tampering characteristic fingerprint information acquired from the image watermark to determine whether the anti-counterfeiting anti-tampering characteristic fingerprint information is consistent with the anti-counterfeiting anti-tampering characteristic fingerprint information acquired from the image watermark, if so, the verification is passed, the success and the characteristic element characters of the PDF document are returned, and if not, the verification is not passed, and an error is returned;
the PDF document verification system returns a verification result to the user, wherein the verification result comprises passing or failing verification; and if the verification is passed, the PDF document verification system simultaneously displays the characteristic element characters of the PDF document to the user.
In this embodiment, the watermark verification API has the same configuration information about the content to be protected and the feature element text to be extracted of the PDF document as the watermark addition API.
In this embodiment, the watermark verification API is configured with a private key (e.g., configured in a cryptographic module) corresponding to the public key configured by the watermarking API in embodiment 1, for decrypting the encrypted anti-counterfeit and anti-tampering feature fingerprint information.
Examples 5,
The embodiment is to perform anti-counterfeiting and anti-tampering verification on the PDF document containing the anti-counterfeiting and anti-tampering picture generated in embodiment 2, and the difference between the embodiment and embodiment 4 is as follows: the same symmetric key as the watermark adding API in embodiment 2 is configured for the watermark verification API, and is used to decrypt the encrypted anti-counterfeit and tamper-resistant feature fingerprint information.
Examples 6,
The embodiment is to perform anti-counterfeiting and anti-tampering verification on the PDF document containing the anti-counterfeiting and anti-tampering picture generated in embodiment 3, and the difference between the embodiment and embodiment 4 is as follows: the same seed key as the watermarking API in embodiment 3 is configured for the watermark verification API, and is used to generate a symmetric key required for decrypting the encrypted anti-counterfeiting and tamper-resistant feature fingerprint information.
Based on the PDF document anti-counterfeiting and anti-tampering watermark embedding method, a corresponding PDF document anti-counterfeiting and anti-tampering watermark embedding system can be constructed, and the system comprises a PDF document generation system and a watermark adding API; the PDF document generation system and the watermark adding API according to the PDF document anti-counterfeiting and anti-tampering watermark embedding method comprise the step of generating the PDF document containing the anti-counterfeiting and anti-tampering watermark picture by implementing the embodiment 1, 2 or 3.
Based on the above-mentioned PDF document anti-counterfeiting anti-tampering verification method, a corresponding PDF document anti-counterfeiting anti-tampering verification system can be constructed, which includes a PDF document verification system and a watermark verification API, and when a user needs to verify the authenticity of a PDF document, the PDF document verification system and the watermark verification API verify the authenticity of the PDF document according to the PDF document anti-counterfeiting anti-tampering verification method, including by implementing the foregoing embodiment 4, 5 or 6.
As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application and not for limiting the protection scope thereof, and although the present application is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: numerous variations, modifications, and equivalents will occur to those skilled in the art upon reading the present application and are within the scope of the claims appended hereto.
Claims (10)
1. A PDF document anti-counterfeiting and anti-tampering watermark embedding method is characterized by comprising the following steps:
when generating a PDF document, the PDF document generation system calls a watermark adding API to request generation and addition of an anti-counterfeiting and anti-tampering watermark; the PDF document generation system submits a request to the watermark adding API, wherein the request comprises a PDF document and a picture to be added with a watermark;
the watermark adding API acquires the content to be protected from the PDF document, and calculates to obtain the hash value of the content to be protected;
extracting appointed or specified characteristic element characters from the PDF document by the watermark adding API;
the watermark adding API combines the hash values of the characteristic element characters and the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
the watermark adding API encrypts the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document;
the watermark adding API adds the encrypted anti-counterfeiting and tamper-proof characteristic fingerprint information as a watermark to the picture, and then adds the picture added with the watermark to the PDF document;
the watermark adding API returns the PDF document added with the picture containing the watermark to a PDF document generating system for further processing and/or storage;
the watermark refers to a digital watermark embedded in a picture.
2. The PDF document anti-counterfeiting and anti-tampering watermark embedding method according to claim 1, characterized in that:
the digital watermarking algorithm adopted by the PDF document anti-counterfeiting and anti-tampering watermark embedding method comprises a fragile watermarking algorithm and a non-fragile watermarking algorithm.
3. The PDF document anti-counterfeiting and anti-tampering watermark embedding method according to claim 1, characterized in that:
the content to be protected and the feature element text to be extracted in the PDF document are appointed, specified or set by configuration information aiming at a watermark adding API.
4. The PDF document anti-counterfeiting and anti-tampering watermark embedding method according to claim 1, characterized in that:
the encryption algorithm adopted for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information is a symmetric key encryption algorithm or an asymmetric key encryption algorithm;
if an asymmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information, adding an API (application program interface) for the watermark and configuring a public key for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information;
if the anti-counterfeiting and anti-tampering feature fingerprint information is encrypted by adopting a symmetric key encryption algorithm, the symmetric keys used for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same or different.
5. The PDF document anti-counterfeiting and anti-tampering watermark embedding method according to claim 4, wherein:
if a symmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document, and the symmetric keys adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are the same, configuring a symmetric key for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents aiming at the watermark adding API;
if a symmetric key encryption algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document, and the symmetric keys adopted for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of different PDF documents are different, configuring a seed key for the watermark adding API; when the anti-counterfeiting and anti-tampering feature fingerprint information of a PDF document is encrypted, the watermarking API or the cryptographic module called by the watermarking API generates a symmetric key for encrypting the anti-counterfeiting and anti-tampering feature fingerprint information of the PDF document by using the seed key and the identification information of the PDF.
6. A PDF document anti-counterfeiting and anti-tampering watermark embedding system of a PDF document anti-counterfeiting and anti-tampering watermark embedding method is characterized in that:
the system comprises a PDF document generation system and a watermark adding API; and the PDF document generation system and the watermark adding API generate the PDF document containing the anti-counterfeiting and anti-tampering watermark picture according to the anti-counterfeiting and anti-tampering watermark embedding method of the PDF document.
7. A PDF document anti-counterfeiting and anti-tampering verification method based on a PDF document anti-counterfeiting and anti-tampering watermark embedding method is characterized in that:
when a user needs to verify the authenticity of a PDF document, submitting the PDF document to a PDF document verification system;
the PDF document verification system calls a watermark verification API and submits a verification request to the watermark verification API; the verification request submitted to the watermark verification API comprises a PDF document to be verified and submitted by a user;
extracting an image added with an anti-counterfeiting and anti-tampering watermark from a PDF document to be verified by the watermark verification API, extracting the added watermark from the image, and extracting encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information from the watermark;
the watermark verification API decrypts the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information to obtain a plaintext of the anti-counterfeiting and anti-tampering characteristic fingerprint information contained in the watermark, namely a combination of characteristic element characters of the PDF document and a hash value of content to be protected when the watermark is added;
the watermark verification API extracts contents to be protected and characteristic element characters from the PDF document to be verified, and calculates a hash value of the contents to be protected extracted from the PDF document to be verified;
the watermark verification API combines the characteristic element characters obtained from the PDF document and the hash value of the content to be protected as the anti-counterfeiting and anti-tampering characteristic fingerprint information of the PDF document to be verified;
the watermark verification API compares the anti-counterfeiting anti-tampering characteristic fingerprint information generated from the PDF document to be verified with the anti-counterfeiting anti-tampering characteristic fingerprint information acquired from the image watermark to determine whether the anti-counterfeiting anti-tampering characteristic fingerprint information is consistent with the anti-counterfeiting anti-tampering characteristic fingerprint information acquired from the image watermark, if so, the verification is passed, the success and the characteristic element characters of the PDF document are returned, and if not, the verification is not passed, and an error is returned;
the PDF document verification system returns a verification result to the user, wherein the verification result comprises passing or failing verification; and if the verification is passed, the PDF document verification system simultaneously displays the characteristic element characters of the PDF document to the user.
8. The PDF document anti-counterfeiting and anti-tampering verification method according to claim 7, wherein:
the watermark verification API has the same configuration information about the content of the PDF document to be protected and the characteristic element characters to be extracted as the watermark adding API;
if an asymmetric key algorithm is adopted for encrypting the anti-counterfeiting and anti-tampering characteristic fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method, a private key corresponding to a public key configured by the watermark adding API is configured for the watermark verification API and is used for decrypting the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information;
if the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method is a symmetric key encryption algorithm, and the symmetric keys used for the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information of different PDF documents are the same, the symmetric key which is the same as the watermark adding API is configured for the watermark verification API and is used for decrypting the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information.
9. The PDF document anti-counterfeiting and anti-tampering verification method according to claim 8, wherein:
if the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information in the PDF document anti-counterfeiting and anti-tampering watermark embedding method is a symmetric key encryption algorithm, and the symmetric keys adopted for the encryption of the anti-counterfeiting and anti-tampering characteristic fingerprint information of different PDF documents are different, the same seed key as the watermark adding API is configured for the watermark verification API and is used for generating a symmetric key required for decrypting the encrypted anti-counterfeiting and anti-tampering characteristic fingerprint information.
10. A PDF document anti-counterfeiting and anti-tampering verification system based on a PDF document anti-counterfeiting and anti-tampering verification method is characterized in that:
the system comprises a PDF document verification system and a watermark verification API, wherein when a user needs to verify the authenticity of the PDF document, the PDF document verification system and the watermark verification API verify the authenticity of the PDF document according to the PDF document anti-counterfeiting anti-tampering verification method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911403328.7A CN111177666A (en) | 2019-12-30 | 2019-12-30 | Forensic document anti-counterfeiting and anti-tampering method and system based on fragile watermark |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911403328.7A CN111177666A (en) | 2019-12-30 | 2019-12-30 | Forensic document anti-counterfeiting and anti-tampering method and system based on fragile watermark |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111177666A true CN111177666A (en) | 2020-05-19 |
Family
ID=70654254
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911403328.7A Pending CN111177666A (en) | 2019-12-30 | 2019-12-30 | Forensic document anti-counterfeiting and anti-tampering method and system based on fragile watermark |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111177666A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111679800A (en) * | 2020-06-10 | 2020-09-18 | 天津光电久远科技有限公司 | Official document anti-counterfeiting printing system based on domestic operating system |
| CN111914304A (en) * | 2020-08-14 | 2020-11-10 | 联想图像（天津）科技有限公司 | Document verification method and device, computer equipment and readable storage medium |
| CN114760392A (en) * | 2022-06-15 | 2022-07-15 | 湖南工商大学 | Document tampering detection method based on blind watermark and asymmetric encryption |
| CN115688059A (en) * | 2021-07-30 | 2023-02-03 | 瑞庭网络技术（上海）有限公司 | Image data processing method and device, electronic equipment and storage medium |
| CN117272396A (en) * | 2023-11-22 | 2023-12-22 | 人力资源和社会保障部人事考试中心 | Anti-tampering method for test result |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103001768A (en) * | 2011-09-13 | 2013-03-27 | 东方钢铁电子商务有限公司 | Electronic quality certificate and generation and verification method thereof |
| CN103154957A (en) * | 2010-10-14 | 2013-06-12 | 韩国电子通信研究院 | Method for extracting fingerprint of publication, apparatus for extracting fingerprint of publication, system for identifying publication using fingerprint, and method for identifying publication using fingerprint |
| CN104200138A (en) * | 2014-09-01 | 2014-12-10 | 北京金石威视科技发展有限公司 | Offline document identifying method |
| CN108805787A (en) * | 2018-04-17 | 2018-11-13 | 北京溯斐科技有限公司 | A kind of method and apparatus that paper document distorts Jianzhen |
| CN109670281A (en) * | 2017-10-16 | 2019-04-23 | 北京大学 | The treating method and apparatus of electronic document |
-
2019
- 2019-12-30 CN CN201911403328.7A patent/CN111177666A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103154957A (en) * | 2010-10-14 | 2013-06-12 | 韩国电子通信研究院 | Method for extracting fingerprint of publication, apparatus for extracting fingerprint of publication, system for identifying publication using fingerprint, and method for identifying publication using fingerprint |
| US20130290330A1 (en) * | 2010-10-14 | 2013-10-31 | Electronics & Telecommunications Research Institut | Method for extracting fingerprint of publication, apparatus for extracting fingerprint of publication, system for identifying publication using fingerprint, and method for identifying publication using fingerprint |
| CN103001768A (en) * | 2011-09-13 | 2013-03-27 | 东方钢铁电子商务有限公司 | Electronic quality certificate and generation and verification method thereof |
| CN104200138A (en) * | 2014-09-01 | 2014-12-10 | 北京金石威视科技发展有限公司 | Offline document identifying method |
| CN109670281A (en) * | 2017-10-16 | 2019-04-23 | 北京大学 | The treating method and apparatus of electronic document |
| CN108805787A (en) * | 2018-04-17 | 2018-11-13 | 北京溯斐科技有限公司 | A kind of method and apparatus that paper document distorts Jianzhen |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111679800A (en) * | 2020-06-10 | 2020-09-18 | 天津光电久远科技有限公司 | Official document anti-counterfeiting printing system based on domestic operating system |
| CN111914304A (en) * | 2020-08-14 | 2020-11-10 | 联想图像（天津）科技有限公司 | Document verification method and device, computer equipment and readable storage medium |
| CN115688059A (en) * | 2021-07-30 | 2023-02-03 | 瑞庭网络技术（上海）有限公司 | Image data processing method and device, electronic equipment and storage medium |
| CN115688059B (en) * | 2021-07-30 | 2023-09-29 | 瑞庭网络技术（上海）有限公司 | Image data processing method and device, electronic equipment and storage medium |
| CN114760392A (en) * | 2022-06-15 | 2022-07-15 | 湖南工商大学 | Document tampering detection method based on blind watermark and asymmetric encryption |
| CN117272396A (en) * | 2023-11-22 | 2023-12-22 | 人力资源和社会保障部人事考试中心 | Anti-tampering method for test result |
| CN117272396B (en) * | 2023-11-22 | 2024-02-02 | 人力资源和社会保障部人事考试中心 | Anti-tampering method for test result |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10755252B1 (en) | Identifying copyrighted material using embedded copyright information | |
| CN111177666A (en) | Forensic document anti-counterfeiting and anti-tampering method and system based on fragile watermark | |
| EP3673455B1 (en) | Identifying copyrighted material using embedded copyright information | |
| Celik et al. | Hierarchical watermarking for secure image authentication with localization | |
| JP3919673B2 (en) | Apparatus and method for distributing and authenticating data sets using watermarks | |
| KR100465950B1 (en) | Information processing apparatus and its control method, storage medium storing computer program | |
| US6504941B2 (en) | Method and apparatus for digital watermarking of images | |
| EP3673392B1 (en) | Copyright protection based on hidden copyright information | |
| WO2014154109A1 (en) | Generating method, verifying method for electronic bill with anti-fake two dimension (2d) code and system for same | |
| JPH11234264A (en) | Electronic papermarking system, electronic information distribution system using the same and storage medium | |
| JP2007104643A (en) | Information processing apparatus, verification processing apparatus, control methods thereof, computer program, and storage medium | |
| EP3673453B1 (en) | Identifying copyrighted material using copyright information embedded in tables | |
| JP2008503162A (en) | System and method for digital content security | |
| EP3673390B1 (en) | Identifying copyrighted material using embedded copyright information | |
| CN114119332A (en) | Block chain-based digital watermark writing and reading method and device | |
| Kumar et al. | A review on digital watermarking-based image forensic technique | |
| Lin et al. | Robust digital signature for multimedia authentication | |
| Dadkhah et al. | Efficient image authentication and tamper localization algorithm using active watermarking | |
| Nyeem et al. | Modelling attacks on self-authentication watermarking | |
| Mandolkar | RSE for electronic text document protection | |
| Chowdhury et al. | Dynamic authentication protocol using multiple signatures | |
| JPH11212462A (en) | Electronic watermark system, electronic information delivery system, picture filing device, and storage medium | |
| Hachim et al. | Cloud-based digital watermarking model for medical image integrity | |
| US20230410072A1 (en) | Systems and methods for enhanced non-fungible tokens | |
| JP2005175652A (en) | Content distribution system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |