CN102496137B - Method and device for dynamically generating watermark - Google Patents
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- CN102496137B CN102496137B CN 201110424816 CN201110424816A CN102496137B CN 102496137 B CN102496137 B CN 102496137B CN 201110424816 CN201110424816 CN 201110424816 CN 201110424816 A CN201110424816 A CN 201110424816A CN 102496137 B CN102496137 B CN 102496137B
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Abstract
The invention discloses a method and device for dynamically generating a watermark. The method comprises the following steps of: selecting any one page of an original file; querying a source character same as a usable character in a usable character library in any one file page so as to extract one or more usable characters from a current file page; and generating a background watermark of the current file page according to the extracted one or more usage characters. Through the method and device for dynamically generating the watermark, disclosed by the invention, the watermark of each page of the original file can be dynamically generated, and the safety of the original file is higher due to difference of the watermark of each file page.
Description
Technical field
The present invention relates to information security field, in particular to a kind of method and device of dynamic generating watermark.
Background technology
Electronic government documents or document exchange are a kind of by Computer information network, between commensurate, are not transmitting the technology of electronic government documents.Along with the development of infotech especially internet technique, each unit or intramural each department can connect mutually by LAN (Local Area Network) or WWW.Simultaneously, constituent parts or department also generally adopt the computword software for editing to draft official document or document.Electronic government documents or document exchange technology are exactly based on this, by standard electronic government documents form, unified conveying flow and record, a kind of technology and the system of internet safe transmission means are provided, make official document just can, with electronic form, from issuing unit, by network, be delivered to rapidly recruiting unit, no longer need the special messenger to be delivered between each unit, thereby, alleviate workload, increase work efficiency.Development along with infotech, official document or document exchange particularly electronic government documents or document exchange day by day frequent, no matter be in the process of party and government's authority management national affairs, or, in the daily administration of enterprises and institutions, official document or document are the important carriers that transmits important information, implements higher level's spirit.Therefore, reinforcement is to the particularly management of electronic government documents or document of official document or document, make electronic government documents or document there is certain confidentiality and antifalsification just seems particularly important, and for the special document of some special machine-operated department, the confidentiality of document and false proofly there is even more important meaning.In prior art, most of official document or document do not have false proof function, normally by source and the true and false of the sequence number on official document or document or official seal judgement official document.But the sequence number on official document or document can be easily blocked or copied, and present chromoscan, duplicating and printing technique make the official seal on official document or document also hold very much to such an extent that be replicated.
Prior art is encrypted and identification in order to realize, can use the digital watermark technology of text, and it is the important technology in the Information Hiding Techniques field, more commonly image digital watermark.And there is a large amount of text (as electronic government documents) need to be keep secret in reality, the text that electronic format can be limited in electronic document system inside flows out, this type systematic often limits by modes such as restriction printing times the file that transfers papery in addition, once but after transferring papery to, system can't limit duplicating, often also can't follow the trail of the primary source of paper document.
Fix for the image digital watermark due to the use of the file after encrypting by digital watermark technology of correlation technique at present, cause the low problem of encrypted document security, not yet propose at present effective solution.
Summary of the invention
The image digital watermark due to the use of the file after encrypting by digital watermark technology for correlation technique is fixed, cause the low problem of encrypted document security, not yet propose effective problem at present and propose the present invention, for this reason, fundamental purpose of the present invention is to provide a kind of method and device of dynamic generating watermark, to address the above problem.
To achieve these goals, according to an aspect of the present invention, provide a kind of method of dynamic generating watermark, the method comprises: choose any page file in source document; In any one page file, the inquiry source word identical with available word in available character library accords with, to extract one or more available word from the current page file; Generate the background watermark of current page file according to one or more available word of extracting.
Further, the background watermark that generates the current page file according to one or more available word of extracting comprises: all available word of extracting are divided into groups according to default group number, to obtain the available word group of predetermined number; Watermark corresponding to the available word group convert to according to pre-defined rule, to generate the background watermark of current page file.
Further, according to pre-defined rule, watermark corresponding to the available word group convert to, comprise with the background watermark that generates source document: the watermark value α that calculates any one group of available word group according to following formula:
wherein, x
ifor the ISN of character in this group available word group, the number that m is watermark kind in the watermark content set, i is natural number; The corresponding watermark of each watermark value α of inquiry in the watermark content set, to obtain the watermark of all available word groups; All watermarks are combined to obtain to the background watermark of source document.
Further, all available word of extracting are divided into groups according to default group number, comprised with the available word group of obtaining predetermined number: all available word of extracting are sorted in order; All available word after sequence are distributed equally according to the group number, to obtain the available word group of predetermined number.
Further, after from the current page file, extracting one or more available word, method also comprises: delete the available word repeated in all available word.
Further, after the background watermark that generates the current page file, method also comprises: the background watermark is embedded to the current page file.
To achieve these goals, according to a further aspect in the invention, provide a kind of device of dynamic generating watermark, this device comprises: select module, for choosing any page file of source document; Extraction module, accord with for the source word identical with available word in available character library in any one page file inquiry, to extract one or more available word from the current page file; Generation module, generate the background watermark of current page file for the one or more available word according to extracting.
Further, generation module comprises: grouping module, for all available word by extracting, according to default group number, divided into groups, to obtain the available word group of predetermined number; Modular converter, for according to pre-defined rule, watermark corresponding to the available word group converting to, to generate the background watermark of current page file.
Further, modular converter comprises: computing module, for calculate the watermark value α of any one group of available word group according to following formula:
wherein, x
ifor the ISN of character in this group available word group, the number that m is watermark kind in the watermark content set, i and n are natural number; Enquiry module, in the watermark content set, inquiring about the corresponding watermark of each watermark value α, to obtain the watermark of all available word groups; Composite module, combined to obtain the background watermark of source document for the watermark by all.
Further, grouping module comprises: order module, sorted in order for all available word by extracting; The mean allocation module, be distributed equally according to the group number for all available word by after sequence, to obtain the available word group of predetermined number.
Further, device also comprises: removing module, the available word repeated for deleting all available word; Merge module, for embedding the current page file by the background watermark.
By the present invention, adopt and choose any page file in source document; In any one page file, the inquiry source word identical with available word in available character library accords with, to extract one or more available word from the current page file; Generate the background watermark of current page file according to one or more available word of extracting, the image digital watermark due to the use of the file after encrypting by digital watermark technology that has solved correlation technique is fixed, cause the low problem of encrypted document security, and then realize dynamically generating the watermark of every one page document of original document, because the watermark difference of every page of document makes the higher effect of security of original document.
The accompanying drawing explanation
Accompanying drawing described herein is used to provide a further understanding of the present invention, forms the application's a part, and schematic description and description of the present invention the present invention does not form inappropriate limitation of the present invention for explaining.In the accompanying drawings:
Fig. 1 is the apparatus structure schematic diagram according to the dynamic generating watermark of the embodiment of the present invention;
Fig. 2 is the method flow diagram according to the dynamic generating watermark of the embodiment of the present invention.
Embodiment
It should be noted that, in the situation that do not conflict, embodiment and the feature in embodiment in the application can combine mutually.Describe below with reference to the accompanying drawings and in conjunction with the embodiments the present invention in detail.
Fig. 1 is the apparatus structure schematic diagram according to the dynamic generating watermark of the embodiment of the present invention.
As shown in Figure 1, this device comprises selects module 10, for choosing any page file of source document; Extraction module 30, accord with for the source word identical with available word in available character library in any one page file inquiry, to extract one or more available word from the current page file; Generation module 50, generate the background watermark of current page file for the one or more available word according to extracting.
The above embodiments of the present application are done common factor by extraction module 30 by the set of all characters of certain one page in source document and the available character library (available word set) distributed, obtain all available word in this page, and all available word set that utilize common factor to obtain are according to certain regular generation background watermark.Because the available word set of extracting in every one page can be not identical, so the watermark difference of every page of generation, thereby having realized the dynamic generating watermark of original document, in the original document use procedure, security is higher.
In the above embodiments of the present application, generation module 50 can comprise: grouping module 501, for all available word by extracting, according to default group number, divided into groups, to obtain the available word group of predetermined number; Modular converter 502, for according to pre-defined rule, watermark corresponding to the available word group converting to, to generate the background watermark of current page file.This grouping module 501 can be divided into groups according to the ingredient of watermark, and, to being changed according to rule in each grouping, this mode makes every page of watermark relevant with this page of content, according to user's request, has realized dynamic generating watermark.To meet consumers' demand.
In the above embodiments of the present application, modular converter 502 can comprise: computing module, for calculate the watermark value α of any one group of available word group according to following formula:
wherein, x
ifor the ISN of character in this group available word group, the number that m is watermark kind in the watermark content set, i and n are natural number; Enquiry module, in the watermark content set, inquiring about the corresponding watermark of each watermark value α, to obtain the watermark of all available word groups; Composite module, combined to obtain the background watermark of source document for the watermark by all.Above-described embodiment, according to the available word set and the rule of correspondence thereof that set in advance, can make the generation background watermark dynamically generate, and what use is simple in rule, and speed is fast and be easy to realization, has met in actual implementation process and has obtained the document that safer efficiency is higher.
Preferably, grouping module 501 can comprise: order module, sorted in order for all available word by extracting; The mean allocation module, be distributed equally according to the group number for all available word by after sequence, to obtain the available word group of predetermined number.In this embodiment, adopt the method for mean allocation to improve the each several part safe effect of the watermark that embeds this page identical.
Preferably, said apparatus can also comprise: removing module, and the available word repeated for deleting all available word, this module can improve encryption efficiency.And merge module, for the background watermark is embedded to the current page file.。
Fig. 2 is that the method comprises the steps: as shown in Figure 2 according to the method flow diagram of the dynamic generating watermark of the embodiment of the present invention
Step S102, realize choosing any page file in source document by the selection module 10 in Fig. 1.
Step S104, realize that by the extraction module 30 in Fig. 1 in any one page file inquiry source word identical with available word in available character library accords with, to extract one or more available word from the current page file.Concrete, this step realizes the character stream in any one page extracted and available character library are got to common factor, thereby obtains all available word of this page file.
Step S106, realize generating according to one or more available word of extracting the background watermark of current page file by the generation module 50 in Fig. 1.
The above embodiments of the present application are done common factor by the set of all characters of certain one page in source document and the available character library (available word set) distributed, obtain all available word in this page, and all available word set that utilize common factor to obtain are according to certain regular generation background watermark.Because the available word set of extracting in every one page can be not identical, so the watermark difference of every page of generation, thereby having realized the dynamic generating watermark of original document, in the original document use procedure, security is higher.
The background watermark that step S106 in the above embodiments of the present application generates the current page file according to one or more available word of extracting can comprise: all available word of extracting are divided into groups according to default group number, to obtain the available word group of predetermined number; Watermark corresponding to the available word group convert to according to pre-defined rule, to generate the background watermark of current page file.This embodiment realizes using the mode that will be changed after the available word grouping to obtain the watermark of every one page.Concrete, the character quantity (available characters is quantity and the character in available character library) of all available word that can be in statistics source document one page afterwards, is calculated according to rule, according to results conversion, becomes the background watermark.Preferably, can determine packet count according to watermark kind sequence and background in the watermark content set.
Step in above-mentioned enforcement: watermark corresponding to the available word group convert to according to pre-defined rule, can comprise with the background watermark that generates source document: the watermark value α that calculates any one group of available word group according to following formula:
wherein, x
ifor the ISN of character in this group available word group, the number that m is watermark kind in the watermark content set, i and n are natural number; The corresponding watermark of each watermark value α of inquiry in the watermark content set, to obtain the watermark of all available word groups; All watermarks are combined to obtain to the background watermark of source document.The classified statistics of this embodiment based on the background watermark are replaced every page of character, and this character can be the gene word.
Step in above-described embodiment: all available word of extracting are divided into groups according to default group number, can comprise with the available word group of obtaining predetermined number: all available word of extracting are sorted in order; All available word after sequence are distributed equally according to the group number, to obtain the available word group of predetermined number.
Preferably, after from the current page file, extracting one or more available word, method also comprises: delete the available word repeated in all available word.
Preferably, after the background watermark that generates the current page file, method also comprises: the background watermark is embedded to the current page file.This step realizes obtaining adding the file after watermark.
In the above embodiments of the present application in advance known data be source document, available character library, watermark sorted table and the set of background watermark content, simultaneously, need the checking source document, available character library, and the validity of corresponding watermark sorted table, integrality, and the figure place of generating watermark.Wherein, watermark sorted table: the set of the watermark figure of each symbology
Concrete, the application can describe the present invention by following example.Certain one page document of take in original document is example, extracts the character that the document comprises as follows: " the main utilization in mountain is occured simultaneously and corresponding collection ".Suppose that known available character library (available word set) is: it is right that the main utilization in mountain is occured simultaneously; The watermark content set of corresponding background is to comprise: 26 letters of a-z; And can determine that according to the number of watermark kind in known watermark content set the background watermark can be divided into 4 parts and form.
After the character by extracting " the main utilization in mountain is occured simultaneously and corresponding collection " is got common factor with available character library, contain altogether 8 available word (can comprise repetition) in this section word: the main utilization in mountain is occured simultaneously to collection.Because the known background watermark is comprised of 4 parts, therefore, this section word extracted can be divided in order to four groups:
First group: the mountain master
Second group: utilize
The 3rd group: occur simultaneously
The 4th group: to collection
After grouping, can be by after character ISN additions all in each group, to the delivery as a result of addition, thereby obtain the watermark value α of every group of character group, the corresponding watermark of each watermark value α.The number of watermark kind in the corresponding watermark content set of this mould m, concrete equation is as follows:
wherein, x
ifor the character ISN, mod is for asking mould, and in the corresponding watermark content set of m, the number of watermark kind, generate thereby pass through this formula the watermark content of inserting corresponding documentation page, from above, can obtain:
First group: (0x5C71+0x 4E3B) mod 26=12
The watermark of 12 correspondences is M
Second group; (0x5229+0x7528) mod 26=13
The watermark of 13 correspondences is N
The 3rd group: (0x 4EA4+0x 96C6) mod 26=0
The watermark of 0 correspondence is A
The 4th group: (0x 5BF9+0x 96C6) mod 26=3
The watermark of 3 correspondences is D
Thereby known, the background watermark of current page is comprised of MNAD, other pages by that analogy, finally are added in file.
It should be noted that, in the step shown in the process flow diagram of accompanying drawing, can in the computer system such as one group of computer executable instructions, carry out, and, although there is shown logical order in flow process, but in some cases, can carry out step shown or that describe with the order be different from herein.
As can be seen from the above description, the present invention has realized following technique effect: according to the available word set and the rule of correspondence thereof that set in advance, capable of dynamic generates the background watermark of corresponding page document, the security that has improved original document.
Obviously, those skilled in the art should be understood that, above-mentioned each module of the present invention or each step can realize with general calculation element, they can concentrate on single calculation element, perhaps be distributed on the network that a plurality of calculation elements form, alternatively, they can be realized with the executable program code of calculation element, thereby, they can be stored in memory storage and be carried out by calculation element, perhaps they are made into respectively to each integrated circuit modules, perhaps a plurality of modules in them or step being made into to the single integrated circuit module realizes.Like this, the present invention is not restricted to any specific hardware and software combination.
The foregoing is only the preferred embodiments of the present invention, be not limited to the present invention, for a person skilled in the art, the present invention can have various modifications and variations.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., within all should being included in protection scope of the present invention.
Claims (7)
1. the method for a dynamic generating watermark, is characterized in that, comprising:
Choose any page file in source document;
In described any page file, the inquiry source word identical with available word in available character library accords with, to extract one or more available word from the current page file, described one or more available word of extracting are character stream in described any one page and the common factor of described available character library;
Generate the background watermark of described current page file according to described one or more available word of extracting,
Wherein, the background watermark that generates described current page file according to described one or more available word of extracting comprises: all available word of extracting are divided into groups according to default group number, to obtain the available word group of predetermined number; Watermark corresponding to described available word group convert to according to pre-defined rule, to generate the background watermark of described current page file,
Wherein, according to pre-defined rule, watermark corresponding to described available word group convert to, comprise with the background watermark that generates described source document: the watermark value α that calculates any one group of available word group according to following formula:
wherein, x
ifor the ISN of character in this group available word group, the number that m is watermark kind in the watermark content set, i and n are natural number; The corresponding watermark of each watermark value α of inquiry in described watermark content set, to obtain the watermark of all available word groups; All watermarks are combined to obtain to the background watermark of described source document.
2. method according to claim 1, is characterized in that, all available word of extracting are divided into groups according to default group number, with the available word group of obtaining predetermined number, comprises:
All available word of extracting are sorted in order;
All available word after sequence are distributed equally according to described group of number, to obtain the available word group of described predetermined number.
3. according to the described method of any one in claim 1-2, it is characterized in that, after from the current page file, extracting one or more available word, described method also comprises: delete the available word repeated in all available word.
4. method according to claim 3, is characterized in that, after the background watermark that generates described current page file, described method also comprises: described background watermark is embedded to the current page file.
5. the device of a dynamic generating watermark, is characterized in that, comprising:
Select module, for choosing any page file of source document;
Extraction module, for the source word identical with available word in available character library in described any page file inquiry, accord with, to extract one or more available word from the current page file, described one or more available word of extracting are character stream in described any one page and the common factor of described available character library;
Generation module, generate the background watermark of described current page file for the described one or more available word according to extracting,
Wherein, described generation module comprises: grouping module, for all available word by extracting, according to default group number, divided into groups, to obtain the available word group of predetermined number; Modular converter, for according to pre-defined rule, watermark corresponding to described available word group converting to, to generate the background watermark of described current page file,
Wherein, described modular converter comprises: computing module, for calculate the watermark value α of any one group of available word group according to following formula:
wherein, x
ifor the ISN of character in this group available word group, the number that m is watermark kind in the watermark content set, i and n are natural number; Enquiry module, in described watermark content set, inquiring about the corresponding watermark of each watermark value α, to obtain the watermark of all available word groups; Composite module, combined to obtain the background watermark of described source document for the watermark by all.
6. device according to claim 5, is characterized in that, described grouping module comprises:
Order module, sorted in order for all available word by extracting;
The mean allocation module, be distributed equally according to described group of number for all available word by after sequence, to obtain the available word group of described predetermined number.
7. according to the described device of any one in claim 5-6, it is characterized in that, described device also comprises:
Removing module, the available word repeated for deleting all available word;
Merge module, for embedding the current page file by described background watermark.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1790420A (en) * | 2005-12-01 | 2006-06-21 | 北京北大方正电子有限公司 | Method and apparatus for embedding and detecting digital watermark in text file |
| JP2010010835A (en) * | 2008-06-24 | 2010-01-14 | Canon Inc | Image processor and image processing method |
| CN101833747A (en) * | 2010-05-10 | 2010-09-15 | 深圳市永达电子股份有限公司 | Method and system for generating digital watermark-based safe word stock |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7760903B2 (en) * | 2005-08-30 | 2010-07-20 | Microsoft Corporation | Tamper-resistant text stream watermarking |
| CN1912864B (en) * | 2006-08-04 | 2010-05-12 | 北京北大方正电子有限公司 | Method of embedding dark lines in sheet |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1790420A (en) * | 2005-12-01 | 2006-06-21 | 北京北大方正电子有限公司 | Method and apparatus for embedding and detecting digital watermark in text file |
| JP2010010835A (en) * | 2008-06-24 | 2010-01-14 | Canon Inc | Image processor and image processing method |
| CN101833747A (en) * | 2010-05-10 | 2010-09-15 | 深圳市永达电子股份有限公司 | Method and system for generating digital watermark-based safe word stock |
Non-Patent Citations (2)
| Title |
|---|
| 文本水印在数字版权管理中的应用研究;罗养霞,等.;《微电子学与计算机》;20080930;第25卷(第9期);115-117 * |
| 罗养霞,等..文本水印在数字版权管理中的应用研究.《微电子学与计算机》.2008,第25卷(第9期),115-117. |
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