CN118014812A - Watermark embedding and watermark extracting methods, devices and equipment - Google Patents

Watermark embedding and watermark extracting methods, devices and equipment Download PDF

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Publication number
CN118014812A
CN118014812A CN202410107475.4A CN202410107475A CN118014812A CN 118014812 A CN118014812 A CN 118014812A CN 202410107475 A CN202410107475 A CN 202410107475A CN 118014812 A CN118014812 A CN 118014812A
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China
Prior art keywords
watermark
granularity
embedded
information
drawing data
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CN202410107475.4A
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汪艺伟
刘泽瀚
訾文泽
汤敏
刘永亮
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Springpower Technology Shenzhen Co Ltd
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Springpower Technology Shenzhen Co Ltd
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Priority to CN202410107475.4A priority Critical patent/CN118014812A/en
Publication of CN118014812A publication Critical patent/CN118014812A/en
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Abstract

The application discloses a watermark embedding and watermark extracting method, device and equipment. The watermark embedding method comprises the following steps: obtaining drawing data, watermark configuration information of the drawing data and watermark information to be embedded into the drawing data; determining one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level; and embedding watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data. By adopting the method, the problem that watermarks with different protection granularities cannot be flexibly embedded according to the safety requirements of drawing data in the prior art is solved.

Description

Watermark embedding and watermark extracting methods, devices and equipment
Technical Field
The present application relates to the field of watermarking technologies, and in particular, to a watermark embedding method, a watermark embedding device, an electronic device, and a storage medium. The application also relates to a watermark extraction method, a watermark extraction device, electronic equipment and a storage medium.
Background
With the wide application of design software such as CAD, the transmission and acquisition of drawing data are more and more convenient. However, since the drawing data can be conveniently copied and modified in the process of storage and transmission, the confidential drawing data is easy to leak and be stolen, and the data security of the drawing data faces a serious challenge.
In the prior art, watermark or electronic seal is generally adopted to protect the data security of drawing data. However, the common bright watermark affects the viewing effect of the drawing data and is also easy to be destroyed and tampered, so that the security of the watermark is greatly affected, for example, the tracing reliability of the watermark is affected. In addition, the prior art lacks a scheme for conveniently adjusting watermark protection granularity according to the security requirement of drawing data, so that the suitability and flexibility of watermark embedding are low.
Therefore, how to flexibly embed watermarks with different protection granularities based on the security requirement of drawing data to achieve the watermark embedding effect with higher security and adaptability is a problem to be solved.
The above information disclosed in the background section is only for enhancement of understanding of the background of the application and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.
Disclosure of Invention
The embodiment of the application provides a watermark embedding method, which aims to solve the problem that watermarks with different protection granularities cannot be flexibly embedded according to the safety requirements of drawing data in the prior art.
The embodiment of the application provides a watermark embedding method, which comprises the following steps: obtaining drawing data, watermark configuration information of the drawing data and watermark information to be embedded into the drawing data; determining one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level; embedding watermark information corresponding to watermark granularity into a carrier object corresponding to the watermark granularity of the drawing data.
Optionally, the determining one or more watermark granularities contained in the watermark configuration information includes: determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object to be embedded with the watermark, which corresponds to the specified watermark granularities, and the target carrier object is at least part of one or more levels of a file level, a layer level, a block level and an entity level of the drawing data; taking the designated watermark granularity contained in the embedding scheme as the watermark granularity contained in the watermark configuration information; the embedding of watermark information corresponding to watermark granularity into the carrier object corresponding to watermark granularity of the drawing data comprises the following steps: and embedding watermark information corresponding to the specified watermark granularity into the target carrier object corresponding to the drawing data and the specified watermark granularity according to the specified watermark granularity contained in the embedding scheme.
Optionally, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to watermark granularity of the drawing data includes: embedding watermark information corresponding to watermark granularity into an existing carrier object corresponding to the watermark granularity of the drawing data; or adding an expansion carrier object corresponding to the watermark granularity to the drawing data, and embedding watermark information corresponding to the watermark granularity into the expansion carrier object.
Optionally, the drawing data is graphic design data stored based on DWG files.
Optionally, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data includes: determining embedded keywords of each watermark granularity; the embedded keywords are keywords preset for watermark granularity or input keywords; for each watermark granularity, watermark information corresponding to the embedded keywords of the watermark granularity is embedded into a carrier object of the drawing data corresponding to the watermark granularity.
Optionally, the embedding watermark information corresponding to the watermark granularity embedded keyword into the watermark granularity carrier object corresponding to the drawing data includes: embedding watermark information corresponding to the embedded keywords into database information corresponding to the watermark granularity; the database information stores the carrier object.
Optionally, the embedding the watermark information corresponding to the embedded keyword into the database information corresponding to the watermark granularity includes: determining target attributes matched with the embedded keywords in a database dictionary corresponding to the watermark granularity; and setting target attributes of the carrier objects in the database dictionary according to the watermark information corresponding to the embedded keywords.
Optionally, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to watermark granularity of the drawing data includes: when the watermark granularity is at the file level, modifying at least one attribute matched with the embedded key words in the file structure, version information and metadata of the drawing data according to watermark information corresponding to the embedded key words of the watermark granularity.
Optionally, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to watermark granularity of the drawing data includes: when the watermark granularity is at the layer level, modifying one or more layer attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or embedding an invisible watermark layer for bearing watermark in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark layer in the form of binary data.
Optionally, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data includes: when the watermark granularity is at the block level, modifying one or more block attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or embedding invisible watermark blocks for bearing watermarks in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark blocks in the form of binary data.
Optionally, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data includes: when the watermark granularity is at an entity level, one or more entity attributes of the drawing data are modified according to watermark information corresponding to the embedded keywords of the watermark granularity.
Optionally, the method further comprises: watermark information embedded in the drawing data for different watermark granularities, including the same or different watermark content; and/or each watermark granularity corresponds to one or more embedded keywords.
Optionally, the method further comprises: and if the embedded keywords are matched with the angle attribute and/or the proportion attribute in the block attribute, modifying the corresponding attribute values within the threshold range so as to realize embedding of the watermark information which is not visible in the vision.
The embodiment of the application also provides a watermark extraction method, which comprises the following steps: obtaining drawing data embedded with watermark information in a carrier object with at least one watermark granularity; the watermark information is embedded into the drawing data based on the watermark embedding method; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level; determining watermark configuration information corresponding to the drawing data, wherein the watermark configuration information comprises one or more watermark granularities; for each watermark granularity, acquiring embedded watermark information from database information corresponding to the watermark granularity.
Optionally, the determining watermark configuration information corresponding to the drawing data includes: determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object embedded with the watermark, which corresponds to the specified watermark granularities; the watermark information is embedded into the drawing data by the watermark embedding scheme; one or more specified watermark granularities contained in the embedding scheme are used as watermark granularities of the watermark configuration information; for each watermark granularity, acquiring embedded watermark information from database information corresponding to the watermark granularity, including: and aiming at each appointed watermark granularity, acquiring watermark information embedded by the target carrier object from database information corresponding to the appointed watermark granularity.
Optionally, the drawing data is graphic design data stored based on DWG files.
Optionally, the method further comprises: determining whether the drawing data contains watermark configuration information according to file attributes of the drawing data; if the drawing data does not contain watermark configuration information, traversing a database dictionary corresponding to each level of watermark granularity in the drawing data, and identifying embedded watermark information according to attribute information contained in the database dictionary.
Optionally, for each watermark granularity, acquiring the embedded watermark information from the database information corresponding to the watermark granularity includes: determining embedded keywords of each watermark granularity; and acquiring embedded watermark information from database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity.
Optionally, the obtaining the embedded watermark information from the database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity includes: determining a database dictionary corresponding to the watermark granularity; acquiring binary data corresponding to the embedded keywords according to target attributes matched with the database dictionary and the embedded keywords; and analyzing the binary data to obtain the original watermark information embedded based on the embedded key words.
Optionally, the obtaining the embedded watermark information from the database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity includes: if the embedded key words represent the invisible layers, traversing a layer database dictionary corresponding to the layers to find the invisible layers embedded with the watermarks, acquiring binary data contained in the invisible layers in the layer database dictionary, and analyzing the binary data to obtain embedded original watermark information; and/or if the embedded keyword represents that the invisible text box is embedded, traversing a block database dictionary corresponding to the block to find the invisible text box embedded with watermark information, reading binary data contained in the invisible text box, and analyzing the binary data to obtain embedded original watermark information.
The embodiment of the application also provides a watermark embedding device, which comprises: the watermark configuration unit is used for obtaining drawing data, watermark configuration information of the drawing data and watermark information to be embedded into the drawing data; a configuration analysis unit, configured to determine one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level; and the watermark embedding unit is used for embedding watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data.
The embodiment of the application also provides a watermark extraction device, which comprises: a drawing data acquisition unit for acquiring drawing data in which watermark information is embedded in a carrier object of at least one watermark granularity; the watermark information is embedded into the drawing data based on the watermark embedding method; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level; a watermark configuration determining unit, configured to determine watermark configuration information corresponding to the drawing data, where the watermark configuration information includes one or more watermark granularities; the watermark extraction unit is used for acquiring embedded watermark information from database information corresponding to each watermark granularity.
The embodiment of the application also provides electronic equipment, which comprises: a memory, and a processor; the memory is used for storing a computer program, and the computer program is executed by the processor to execute the method provided by the embodiment of the application.
The embodiment of the application also provides a computer storage medium which stores computer execution instructions which are used for realizing the method provided by the embodiment of the application when being executed by a processor.
Compared with the prior art, the application has the following advantages:
The embodiment of the application provides a watermark embedding and watermark extracting method, a device, electronic equipment and a storage medium, which are used for determining one or more watermark granularities contained in watermark configuration information of drawing data; embedding corresponding watermark information into a carrier object of the watermark granularity corresponding to the drawing data according to each watermark granularity; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level. Therefore, watermark embedding of one or more layers of watermarks such as drawing level, layer level, block level, entity level and the like is realized in drawing data, and a corresponding watermark extraction method is further provided, watermark information of the multi-layer watermark is extracted, and a drawing data security solution based on the multi-layer watermark is formed. Because each level of watermark granularity can reflect different security requirements of drawing data, the application realizes embedding one or more watermarks with watermark granularity according to the security requirements of the drawing data, provides watermark embedding with different granularity protection at the file (or drawing) level, the layer level, the block level and the entity level, ensures that watermark information is not illegally acquired and tampered to the greatest extent, and improves the data security, the suitability and the flexibility of watermark embedding.
In the preferred scheme, watermark information is embedded into database information of drawing data, so that the watermark information is invisible to a user and does not influence the visual effect of drawings; moreover, the embedding of corresponding watermark information aiming at one or more keywords is realized, so that the watermark of the invention is difficult to tamper, and the robustness and the safety of the watermark are ensured.
Drawings
Fig. 1 is a process flow diagram of a watermark embedding method according to a first embodiment of the present application;
Fig. 2 is a flowchart of a preferred embodiment of a watermark embedding method provided in a first embodiment of the present application;
FIG. 3 is a schematic diagram of a file database dictionary with watermark information according to a first embodiment of the present application;
FIG. 4 is a schematic diagram of a layer database dictionary with watermark information according to a first embodiment of the present application;
FIG. 5 is a schematic diagram of a block database dictionary with watermark information according to a first embodiment of the present application;
FIG. 6 is a diagram of a physical database dictionary with watermark information according to a first embodiment of the present application;
fig. 7 is a process flow diagram of a watermark extraction method according to a second embodiment of the present application;
fig. 8 is a flowchart of a preferred embodiment of a watermark extraction method provided by a second embodiment of the present application;
fig. 9 is a schematic diagram of a watermark embedding device according to a third embodiment of the present application;
Fig. 10 is a schematic diagram of a watermark extraction apparatus according to a fourth embodiment of the present application;
Fig. 11 is a schematic diagram of an electronic device provided by the present application.
Detailed Description
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. The present application may be embodied in many other forms than those herein described, and those skilled in the art will readily appreciate that the present application may be similarly embodied without departing from the spirit or essential characteristics thereof, and therefore the present application is not limited to the specific embodiments disclosed below.
The embodiment of the application provides a watermark embedding method, a watermark embedding device, electronic equipment and a storage medium. The application also provides a watermark extraction method, a watermark extraction device, electronic equipment and a storage medium. The following examples are given one by one.
For easy understanding, first, an application scenario and related concepts of the watermark embedding method and the watermark extraction method provided by the application are provided. This scenario is only one embodiment of the method application scenario, and this scenario embodiment is provided for the purpose of facilitating understanding of the method, and is not intended to limit the method.
Watermarking is a technology for identifying and protecting data content, and can embed specific identification into the data content for proving copyright, revealing traceability, covert communication, detecting tampering or forging, and the like. The application scene of the application comprises the field of CAD (computer aided design) -based drawing design, and can identify the source of drawing data and carry out copyright protection in the modes of watermark embedding and watermark extraction, wherein the watermark embedding method can be applied to a watermark embedding end, and the watermark extraction method can be applied to a watermark extraction end. Drawing data includes, but is not limited to, graphic design data saved in a file format such as DWG (DraWinG, abbreviated DWG) files, DXF files (drawing exchange files, i.e., abbreviations of Drawing Exchange Format), DGN files, and the like. By means of the watermark, the attribution right of the drawing data can be clearly determined, and an unauthorized theft/misuse source can be identified. The watermark embedding method and the watermark extracting method can be applied to a plurality of industries including, but not limited to, engineering design, mechanical manufacturing, electric and electronic circuit application, architectural design, simulation and animation production. Simulation refers to a technology for solving a specific problem by applying a scientific tool (such as a tool based on a virtual reality technology) based on a real system environment model (such as a three-dimensional physical model); animation refers to a method of creating a trailer/animation by modeling with three-dimensional/two-dimensional software, and actually simulating an industrial production site to reproduce a three-dimensional animation/two-dimensional animation/stop-motion animation of a process flow.
DWG file: is a CAD-based file format, a proprietary standard file format used to store and transmit CAD-based graphic design data (including two-dimensional and/or three-dimensional graphic data). DWG files, which consist of a series of graphical objects, such as layers, blocks, and entities, have a multi-hierarchical structure. DWG files may contain various graphical object types such as line segments, arcs, polygons, text, and complex three-dimensional entities.
Entity: the basic graphic elements are the basic graphic elements constituting the graphics in the drawing data, and the basic graphic elements can be points, lines, circles, arcs, polygons, characters, sizes and the like. Each entity has attributes and features specific to the entity, such as type, color, line shape, line width, and location; by combining and arranging entities, complex two-dimensional and/or three-dimensional graphics can be created.
And (3) block: is a composite entity composed of a plurality of graphic elements and can be reused, and the block is also a graphic element. The composite entity is formed like a folder, a plurality of graphic elements can be combined into one block, and then reused in the whole graphic like a single entity.
Layer (c): is a way of organizing drawing data to separate different types of graphical elements. By using layers, graphical elements of different shapes, sizes, colors, lines or line widths can be placed on different layers, respectively. The layer comprises a visible layer and a hidden layer; wherein the visible layer refers to a layer which is currently visible in the design work area, and specific elements can be selectively displayed or hidden by selecting different visible layers so as to perform design and editing better; the hidden layer is a layer that is not visible in the current design work area, through which certain elements may be temporarily removed from the design view to better reveal other elements or simplify the design, which may be redisplayed if desired.
It should be noted that the above disclosed information is only used to aid in understanding the present application, and is not meant to constitute prior art known to those of ordinary skill in the art.
The watermark embedding method according to the first embodiment of the present application is described below with reference to fig. 1 to 6. The watermark embedding method shown in fig. 1 includes: step S101 to step S103.
In step S101, drawing data, watermark configuration information of the drawing data, and watermark information to be embedded in the drawing data are obtained.
The drawing data refers to graphic design data needing watermark information embedding, and the included graphic elements can be divided into multiple layers according to the granularity of objects, and each object granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level. Specifically, one or more existing graphic elements of the drawing data can be used as a digital carrier of the watermark, and corresponding watermark information is embedded in the existing graphic elements; an extended graphic element can be added in the drawing data, the extended graphic element is used as a digital carrier of the watermark, and watermark information is embedded in the extended graphic element. The graphic elements embedded with watermark information are watermark carrier objects, which comprise existing graphic elements and/or extended graphic elements of drawing data. Preferably, the drawing data is graphic design data stored based on DWG files, for example, DWG files with extension of. DWG based on CAD design. Of course, the drawing data may be files of other format types, such as files of formats of dxf, dgn, etc.
The watermark information refers to a mark to be embedded into drawing data, and the mark is embedded into the drawing data to be used for proving copyright, revealing traceability, covert communication, detecting tampering or counterfeiting and other purposes. For example, the watermark information is hidden and embedded into the drawing data, so that the use of the original drawing data is not affected, and the original drawing data is not easy to damage or tamper. The watermark information may include at least one of the following: company name, copyright information, usage person ID, usage time, author information, creation time, transparency specifying a layer, freezing state specifying a layer, proportion of blocks, rotation angle, transparency, freezing state specifying a proportion of entities, rotation angle, transparency, freezing state, or other identification information.
The watermark configuration information refers to configuration information for indicating that watermark information is embedded in drawing data. Preferably, the watermark configuration information comprises one or more watermark granularities, watermark information corresponding to each watermark granularity in the one or more watermark granularities is embedded into the drawing data, and multi-level watermarks corresponding to each watermark granularity can be formed. When the method is implemented, the watermark granularity contained in the watermark configuration information can be planned and designed according to the safety requirement of the drawing data, and particularly, the watermark information needs to be embedded in carrier objects with the granularity according to the safety requirement of the drawing data, and the object granularity of the carrier objects is taken as the watermark granularity. Thus, watermark granularity is a level of granularity matching the object to which the carrier object belongs, one watermark granularity corresponding to at least part of the carrier object at one object granularity. Preferably, the watermark granularity corresponds to the embedded watermark information one by one, and the watermark granularity corresponds to the granularity of the carrier object embedded with the watermark information one by one. Wherein, if the carrier object comprises an extended graphic element, the extended graphic element is also matched with the watermark granularity. For example, if the security requirement of the drawing data is to implement watermark protection at the layer level, a watermark may be embedded in an existing layer object, or one or more layers (especially, invisible layers) may be added as watermark layers dedicated to embedding watermark information. For another example, if the security requirement of the drawing data is to implement watermark protection at the block level, a watermark may be embedded in an existing block object, or one or more blocks (especially invisible blocks, such as invisible text boxes) may be added as watermark blocks dedicated to embedding the watermark. Further, one watermark granularity may correspond to one or more embedded keywords, and the embedded keywords of different watermark granularities may be different, the same or partially the same. Each embedded keyword is used for embedding watermark information corresponding to the keyword into a carrier object of the drawing data corresponding to the watermark granularity of the keyword. In other embodiments, the watermark configuration information comprises a user-selected embedding scheme comprising at least one or more specified levels of specified watermark granularity. Further, the embedding scheme may also contain other information corresponding to the specified watermark granularity; for example, one or more embedded keywords corresponding to a specified watermark granularity; for another example, information of the target carrier object to be embedded with the watermark corresponding to the specified watermark granularity is contained.
In this embodiment, the method further includes: a user interface is provided for inputting drawing data, watermark configuration information, and watermark information to be embedded in the drawing data. Wherein the input drawing data includes: a file identification of the drawing data is specified, the file identification including a file name and possibly a file storage path. Inputting watermark configuration information, comprising: at least one or more watermark granularities are specified for the drawing data. Preferably, the method further comprises: inputting embedded keywords aiming at watermark granularity; the carrier object embedded with the watermark information in the representation drawing data is used for bearing the key attribute of the corresponding watermark information. When the user does not configure the embedded keywords for the watermark granularity, determining the key attributes for carrying watermark information, which are used by the carrier objects corresponding to the watermark granularity, according to the default keywords. Wherein, input watermark information, include: the watermark embedded in the drawing data is specified to include content, watermark information can be specified for a carrier object of a certain type, and watermark information can be specified uniformly for the drawing data. The designation includes user input or selection of relevant configuration information. For example, different watermark granularities may be displayed on a user interface, resulting in a user's selection trigger for watermark granularity. For another example, alternative embedded keywords are displayed in association with watermark granularity selected by a user, and the alternative embedded keywords selected by the user are used as the embedded keywords of the watermark granularity in the watermark configuration information in response to the triggering of the selection of at least one alternative embedded keyword in the alternative embedded keywords by the user. For another example, an input area is provided for the embedded keyword, and user input content is received through the input area as watermark information corresponding to the embedded keyword, or information matched with the embedded keyword is extracted from the drawing data as watermark information corresponding to the embedded keyword.
In step S102, determining one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level.
Specifically, the watermark configuration information is designed and configured by a user according to the security requirement of drawing data, and watermark granularity contained in the watermark configuration information is the basis for embedding watermark information. In this step, one or more watermark granularities are resolved from the watermark configuration information. For example, the watermark configuration information uses four bits to represent watermark granularity, from high bit to low bit4, bit3, bit2, bit1 respectively represent file granularity, layer granularity, block granularity, and entity granularity, the bit position of the corresponding watermark configuration information is 1 when one watermark granularity is adopted, and the corresponding bit position is 0 when one watermark granularity is not adopted; if the watermark configuration information is 1101, it means that the file watermark, the layer watermark and the entity watermark are embedded respectively by adopting the file granularity, the layer granularity and the entity granularity. Further, the watermark configuration information may further include watermark information ID, where the watermark information ID is used to identify watermark information corresponding to the watermark granularity. In implementation, the watermark information ID may be generated or set according to a preset rule, for example, a corresponding watermark information serial number or name may be specified for each watermark granularity included in the watermark configuration information, so as to set the watermark information ID, or the watermark information ID may be generated according to other information. For example, when the watermark is embedded, the granularity of the designated watermark is 1101, and the watermark information ID is 1102, it means that the file watermark, the layer watermark and the entity watermark are embedded respectively, the file watermark is embedded in the first watermark information, the layer is embedded in the first watermark information, and the entity is embedded in the second watermark information. One or more pieces of watermark information can be endowed with the watermark information ID through the watermark information ID, and then the watermark information ID is endowed with watermark granularity, so that the configuration decoupling of the watermark information and the watermark granularity is facilitated, and the watermark configuration is more flexible and convenient instead of strong binding. The same watermark information can be embedded for different watermark granularities, or different watermark information can be embedded. For example, watermark information representing "company name" is embedded for file granularity, watermark information representing "user ID" is embedded for layer granularity, and watermark information representing "use time" is embedded for entity granularity; watermark information corresponding to the "user ID and the use time" may also be embedded for each of the three watermark granularities.
In other embodiments, when the watermark configuration information includes an embedding scheme for embedding the watermark information into the drawing data, and one or more watermark granularities are included in the embedding scheme, the determining the one or more watermark granularities included in the watermark configuration information includes: determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object to be embedded with the watermark, which corresponds to the specified watermark granularities, and the target carrier object is at least part of one or more levels of a file level, a layer level, a block level and an entity level of the drawing data; taking the designated watermark granularity contained in the embedding scheme as the watermark granularity contained in the watermark configuration information; correspondingly, the embedding the watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data comprises the following steps: and embedding watermark information corresponding to the specified watermark granularity into the target carrier object corresponding to the drawing data and the specified watermark granularity according to the specified watermark granularity contained in the embedding scheme. That is, watermark granularity is specified in the embedding scheme and target carrier objects in which watermarks are required to be embedded corresponding to the watermark granularity are specified, so that a user can flexibly control the carrier carrying the watermarks by customizing the target carrier objects, and the effect of controlling the watermark capacity can be achieved. The granularity of various watermarks of the embedding scheme can be different levels of granularity, and the watermark corresponding to the granularity is embedded in the specified graphic element of the object granularity of the corresponding level contained in the drawing data, so that the suitability and the flexibility of watermark embedding are improved. Preferably, watermark information embedded in the drawing data by different watermark granularities of the embedding scheme may comprise the same or different watermark content. For example, a file watermark may be embedded for at least one file of drawing data by the file-level watermark granularity of the embedding scheme; the layer watermark of the corresponding layer can be embedded aiming at least one layer through the watermark granularity of the layer level of the embedding scheme; embedding block watermarks of corresponding blocks for at least one block by block-level watermark granularity of an embedding scheme; by means of the entity level watermark granularity of the embedding scheme, entity watermarks of corresponding entities can be embedded for at least one entity. For example, the watermark granularity of the embedding scheme represents the file watermark, the watermark granularity of the embedding scheme represents the layer watermark, the watermark granularity of the embedding scheme represents the block watermark, the watermark granularity of the embedding scheme represents the entity watermark, the bit position of the corresponding embedding scheme is 1 when a certain watermark granularity is adopted, and the corresponding bit position is 0 when a certain watermark granularity is not adopted; if the embedding scheme of the watermark configuration information is 1101, the file watermark, the layer watermark and the entity watermark are respectively embedded by adopting the watermark granularity I, the watermark granularity II and the watermark granularity IV. The embedding schemes with different watermark granularities can embed the same watermark information or different watermark information. For example, watermark information "company name" is embedded in watermark granularity one, watermark granularity two and watermark granularity four are adopted to embed watermark, watermark information "user ID" is embedded in watermark granularity two, watermark information "use time" is embedded in watermark granularity four; watermark information corresponding to the "user ID and the use time" may also be embedded in each of the three watermark granularities.
In step S103, watermark information corresponding to the watermark granularity is embedded into the carrier object corresponding to the watermark granularity of the drawing data.
Specifically, the carrier object of the watermark granularity corresponding to the drawing data is an existing graphic element which is contained in the drawing data, is matched with the watermark granularity and needs to be embedded with watermark information, and/or an extended graphic element which is added in the drawing data, is matched with the watermark granularity and is used for embedding watermark information. The embedding the watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data comprises the following steps: embedding watermark information corresponding to watermark granularity into existing graphic elements of the drawing data corresponding to the watermark granularity; and/or adding an extended graphic element corresponding to the watermark granularity aiming at the drawing data, and embedding watermark information corresponding to the watermark granularity into the extended graphic element; wherein the existing graphic element and the extended graphic element are the carrier objects. Preferably, watermark information embedded in the drawing data for different watermark granularities comprises the same or different watermark content.
In this embodiment, watermark information with multiple granularities may be embedded in the drawing data at the same time, such as embedding a file ownership for one or more file objects of the drawing data, embedding a layer designer for one or more layer objects of the drawing data, embedding a block responsible person for one or more block objects of the drawing data, and embedding an entity design implementer for one or more entity objects of the drawing data. Different watermark information can be embedded in watermark granularity of different layers (namely different levels) at the same time, such as embedding file ownership information in a file layer, embedding layer designer information in a layer, embedding block responsible person information in a block layer and embedding entity design implementation person information in an entity layer.
Preferably, the drawing data is a database containing graphic design data organized in a certain structure. Watermark information can be embedded into carrier objects stored in a database of drawing data through embedded keywords corresponding to watermark granularity, and attribute information of the carrier objects matched with the embedded keywords is preferably modified according to the embedded keywords; wherein each watermark granularity corresponds to one or more embedded keywords. Each watermark formed after embedding corresponds to the embedded keyword and the embedded content, and the watermark can be extracted and identified according to the corresponding embedded keyword and the embedded content, so that the drawing data can be prevented from being tampered and/or partially lost. Specifically, the embedding watermark information corresponding to watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data includes: determining embedded keywords of each watermark granularity; the embedded keywords are keywords preset for watermark granularity or input keywords; wherein the preset keywords are default keywords; the input keywords are user-defined keywords configured by a user; for each watermark granularity, watermark information corresponding to the embedded keywords of the watermark granularity is embedded into a carrier object of the drawing data corresponding to the watermark granularity. The embedding the watermark information corresponding to the embedded keyword of the watermark granularity into the carrier object of the watermark granularity corresponding to the drawing data includes: embedding watermark information corresponding to the embedded keywords into database information corresponding to the watermark granularity; the database information stores the carrier object. The database information comprises a database dictionary, and records in the database dictionary comprise data contents of graphic elements such as entities, blocks, layers, files and the like. These data contents and the database itself can be used as carrier objects. Specifically, the embedding the watermark information corresponding to the embedded keyword into the database information corresponding to the watermark granularity includes: determining target attributes matched with the embedded keywords in a database dictionary corresponding to the watermark granularity; and setting target attributes of the carrier objects in the database dictionary according to the watermark information corresponding to the embedded keywords. For example, determining one or more target attributes of the watermark granularity level graphical element on the watermark granularity embedded key match; and modifying the attribute value of the target attribute according to the watermark information corresponding to the embedded keyword, thereby realizing the embedding of the watermark into the database information. In practice, the binary data corresponding to the watermark information may be used to modify the attribute value of the target attribute. In implementation, an invisible text box can be added, watermark information is input into the invisible text box, so that watermark embedding is realized, and text type information can be input into the invisible text box. In this embodiment, the watermark information after embedding the drawing data includes, but is not limited to, binary data type information and/or text type information based on text box input. For example, it may also be octal, hexadecimal, graphic images, other types of information encoded in other forms, and the like. In practice, the method further comprises the following steps: in the process of embedding watermark information into a carrier object of drawing data, confusion information for confusing original watermark information and a check code for checking whether the watermark information is correct are added to increase watermark strength. Accordingly, in the watermark extraction process, it is necessary to verify the initial embedded content extracted from the carrier object in which the watermark information is embedded based on the verification code, and then to inverse-solve the correct initial watermark information by the confusion information. Therefore, even if an attacker acquires or guesses the watermark embedding scheme such as guesses the attribute embedded by the watermark, the attacker cannot obtain the real watermark under the condition of uncertain confusing information or specific using mode thereof, thereby achieving the aim of protecting the drawing data.
Referring to fig. 2, there is shown a flow chart of a preferred embodiment of a watermark embedding method, comprising: s201, obtaining a DWG file, namely drawing data to be embedded with watermark information. S202, obtaining watermark information and watermark configuration information. The watermark configuration information at least comprises watermark granularity of an embedding scheme and an embedding keyword. S203, identifying the selected schemes and watermark information corresponding to the selected schemes according to the watermark configuration information. The selected scheme includes one or more watermark granularities. S204, if the watermark granularity is the file watermark of the file level, adding the watermark in the database of the DWG file, and storing the key words and the content of the watermark. The key words of the stored watermarks refer to the embedded key words or the attribute of matching the corresponding carrier objects with the embedded key words; the content of the stored watermark refers to watermark information corresponding to the key. And S205, if the watermark granularity is the file watermark of the layer level, adding the watermark in the database of the target layer, and storing the key words and the content of the watermark. S206, if the watermark granularity is the layer watermark of the block level, adding the watermark in the database of the target block, and storing the key words and the content of the watermark. S207, if the watermark granularity is the layer watermark of the entity level, adding the watermark in the database of the target entity, and storing the key words and the content of the watermark. S208, forming the DWG file containing the watermark.
As a preferred embodiment of watermark information embedding, the embedding watermark information corresponding to watermark granularity in the carrier object corresponding to the watermark granularity of the drawing data includes: when the watermark granularity is at the file level, modifying at least one attribute matched with the embedded key words in the file structure, version information and metadata of the drawing data according to watermark information corresponding to the embedded key words of the watermark granularity.
For example, the watermark granularity at the file level includes embedding watermark information into metadata of a corresponding file of drawing data, specifically, modifying information that matches the embedded keywords at the metadata structure level, such as modifying file author information and creation time using the corresponding watermark information. Further, watermark information is embedded in metadata items such as file author information and creation time in the form of binary character strings. The metadata refers to description information (such as author information, creation time, modification number, etc. information) for the drawing data.
Table 1: modifying author name information for planogram a.dwg files to embed watermarks
The modification of the author name information to embed watermark information "0110" is given in table 1. Referring to fig. 3, a schematic diagram of a file database dictionary with watermark information is shown, including: a file database dictionary, wherein exemplary attributes in the dictionary include: file size, creation date, modification date, file version, and author name, wherein the author name is an embedded keyword or an attribute matching the embedded keyword, in which watermark information "0110" is embedded.
In another preferred embodiment of watermark information embedding, the embedding watermark information corresponding to watermark granularity in the carrier object corresponding to watermark granularity of the drawing data includes: when the watermark granularity is at the layer level, modifying one or more layer attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or embedding an invisible watermark layer for bearing watermark in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark layer in the form of binary data. Wherein the watermark information is embedded through the watermark granularity of the layer level, the designated layer can be modified or at least one of the following layer attributes of at least part of the layer can be modified to obtain the layer watermark: layer name, visibility, color, transparency, line width, line type, frozen state, etc.
For example, modifying transparency attribute of the layer, DWG file layer transparency default value is 0, and transparency may be modified to 1 or other values to implement watermark embedding. For another example, watermark information of "00" indicates that transparency remains unchanged, watermark information of "01" indicates that transparency becomes 1, watermark information of "10" indicates that transparency becomes 2, watermark information of "11" indicates that transparency becomes 3, and so on. For another example, the freeze state attribute of the layer is modified, the freeze representing watermark information is 1, and the non-freeze representing watermark information is 0. Of course, it is also possible to modify multiple attributes of the layer simultaneously to embed watermark information in different attributes, respectively. Further, the invisible layer can be embedded, and watermark information is embedded in the invisible layer in the form of a binary character string, so that the effect of dark watermark is realized.
Table 2: embedding watermark information in layer granularity for b.dwg file
The values of the properties modifying the transparency and freeze state of the layer to embed watermark information "111" are given in table 2. Referring to fig. 4, a schematic diagram of a layer database dictionary with watermark information is shown, including: a file database dictionary, wherein exemplary attributes in the dictionary include: the method comprises the steps of layer name, visibility, transparency and freezing state, wherein the transparency and the freezing state are embedded keywords or attributes matched with the embedded keywords, watermark information 11 and watermark information 1 are respectively embedded in the two attributes, and the obtained layer watermark is 111.
In another preferred embodiment of watermark information embedding, the embedding watermark information corresponding to watermark granularity in the carrier object corresponding to watermark granularity of the drawing data includes: when the watermark granularity is at the block level, modifying one or more block attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or embedding invisible watermark blocks for bearing watermarks in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark blocks in the form of binary data. By embedding watermark information at the block level watermark granularity, at least one of the following block attributes of a given block or at least part of the block may be modified in accordance with the watermark information to obtain a block watermark: block name, visibility, scale, rotation angle, etc.
For example, modifying the rotation angle attribute of the block, such as the rotation angle of the block defaulting to 0 in the DWG file, the angle rotation may be modified to 1 or other values, i.e., the rotation angle becomes 0 for watermark information "00", becomes 1 for watermark information "01", becomes 2 for watermark information "10", and becomes 3 for watermark information "11"; the proportion attribute can be modified, for example, the proportion default value of the block in the DWG file is 1, the proportion can be modified to be 1 or other values, namely, the watermark information is '00', the proportion is 1, the watermark information is '01', the proportion is 1.01, the watermark information is '10', the proportion is 1.02, and the watermark information is '11', and the proportion is 1.03; of course, it is also possible to modify multiple attributes of a block at the same time to embed watermark information in different attributes, respectively. Further, invisible text boxes can be embedded into the specified blocks or at least part of the blocks, and watermark information can be embedded in the form of binary strings.
Table 3: embedding watermark information at block granularity for b.dwg files
The ratio of the modification blocks is given as 1.02 in table 3, and the modification rotation angle is 1 degree, thereby embedding watermark information "1001". Referring to fig. 5, there is shown a schematic diagram of a block database dictionary with watermark information, comprising: a block database dictionary, wherein exemplary attributes in the dictionary include: the method comprises the steps of block name, visibility, proportion and rotation angle, wherein the proportion and the rotation angle are embedded keywords or attributes matched with the embedded keywords, watermark information '10' and watermark information '01' are respectively embedded in the two attributes, and the obtained block watermark is '1001'. Watermark information "10" indicates that the ratio is modified to "1.02", and watermark information "01" indicates that the rotation angle is modified to "1 degree".
In another preferred embodiment of watermark information embedding, the embedding watermark information corresponding to watermark granularity in the carrier object corresponding to watermark granularity of the drawing data includes: when the watermark granularity is at an entity level, one or more entity attributes of the drawing data are modified according to watermark information corresponding to the embedded keywords of the watermark granularity. Wherein, watermark information is embedded through watermark granularity of entity level, and at least one entity attribute of a designated entity or at least part of the entity can be modified according to the watermark information so as to obtain entity watermark: type, location, size, color, transparency, line scale, line width.
For example, modifying the linear scale of the entity, for example, if the default value of the linear scale of the entity in the DWG file is 1, the linear scale may be modified to 1 or other values, i.e., the watermark information is "00", the linear scale becomes 1.00, the watermark information is "01", the linear scale becomes 1.01, the watermark information is "10", the linear scale becomes 1.02, and the watermark information is "11", and the linear scale becomes 1.03; the transparency attribute of the entity can be modified, the transparency default value is 0, the transparency can be modified to be 1 or other values, namely, the transparency is unchanged when watermark information is 00, the transparency is 1 when watermark information is 01, the transparency is 2 when watermark information is 10, and the transparency is 3 when watermark information is 11; of course, it is also possible to modify multiple attributes of an entity at the same time to embed watermark information in different attributes, respectively.
Table 4: embedding watermark information at entity granularity for b.dwg files
The modified entity is given in table 4 with a linear scale of 1.02 and a transparency of 1 degree, thereby embedding watermark information "1001". Referring to fig. 6, there is shown a schematic diagram of a physical database dictionary with watermark information, including: an entity database dictionary, wherein exemplary attributes in the dictionary include: the entity type, the hierarchy, the color, the linear proportion and the transparency, wherein the linear proportion and the transparency are embedded keywords or attributes matched with the embedded keywords, watermark information '10' and watermark information '01' are respectively embedded in the two attributes, and the obtained entity watermark is '1001'. Watermark information "10" indicates that the linear scale is modified to "1.02", and watermark information "01" indicates that the transparency is modified to "1".
The above-described preferred embodiments of watermark information embedding may be combined arbitrarily without conflict.
Further, the method further comprises the following steps: and if the embedded keywords are matched with the angle attribute and/or the proportion attribute in the block attribute, modifying the corresponding attribute values within the threshold range so as to realize embedding of the watermark information which is not visible in the vision. And if the embedded keywords are matched with the angle attribute and/or the scale attribute of the entity/layer, modifying the corresponding attribute values within the threshold range so as to realize embedding of the watermark information which is not visible in vision.
Further, the method further comprises the following steps: and the watermark configuration information is stored in the file attribute of the drawing data, so that watermark extraction and identification are facilitated.
The watermark embedding method provided by the embodiment can realize watermark embedding with multiple granularities (or different levels), and the watermark is embedded from different levels such as a file level, a layer level, a block level, an entity level and the like: the method comprises the steps that a file watermark is realized through watermark embedding at a file level, and the whole file is protected at a drawing level (namely a file level); the watermark of the layer is embedded through the watermark of the layer level, so that the watermark of each layer can be embedded, the watermark protection of the layer level is realized, and the integrity of the watermark is ensured and the watermark is used for copyright protection by identifying the addition and deletion of the layer content; the block watermark is realized through the watermark embedding at the block level, and in the block level, even if a pirate copies only one block, the integrity of the watermark can be ensured and used for copyright protection; the entity watermark is realized through the entity-level watermark embedding, and in the entity level, each entity is embedded with the watermark, so that even if a pirate copies only one line, the integrity of the watermark can be ensured and the watermark can be used for copyright protection. Multiple granularities of watermarks can be embedded at the same time, so that the safety requirements of practical application and drawing data are flexibly met. Furthermore, the watermark is embedded into the database of the drawing data in the embodiment, so that various watermark granularity and embedded keywords can be selected, a plurality of pieces of watermark information can be conveniently added, and the security of the watermark and the watermark information cannot be illegally acquired and tampered to the greatest extent are ensured. And the specific identification information (namely watermark information) is embedded into a database of drawing data, so that hidden watermarks are realized, the attractive appearance and the viewing effect of the drawing are not affected, and the watermark information can be safely, accurately and stably embedded and extracted for identification.
It should be noted that, in the case of no conflict, the features given in this embodiment and other embodiments of the present application may be combined with each other, and steps S101 and S102 or similar terms do not limit that the steps must be performed sequentially.
Thus far, the method provided by this embodiment has been described, where the method determines one or more watermark granularities according to watermark configuration information of drawing data; embedding watermark information corresponding to the watermark granularity into a carrier object corresponding to the watermark granularity of the drawing data according to each watermark granularity; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level. Thus, watermark embedding and watermark extraction at one or more different levels of watermark granularity at the drawing level, the layer level, the block level and the entity level are realized, and a drawing data security solution comprising one or more levels of multi-level watermarks is provided. Because each level of watermark granularity can reflect different security requirements of drawing data, the application realizes embedding one or more watermarks with watermark granularity according to the security requirements of the drawing data, provides watermark embedding with different granularity protection at the file (or drawing) level, the layer level, the block level and the entity level, ensures that watermark information is not illegally acquired and tampered to the greatest extent, and improves the data security, the suitability and the flexibility of watermark embedding.
The second embodiment of the present application provides a watermark extraction method corresponding to the watermark embedding method provided in the first embodiment of the present application. The method is described below with reference to fig. 7 and 8, and the same parts are referred to the description of the corresponding parts of the above embodiments, and will not be repeated. The watermark extraction method shown in fig. 7 includes: step S701 to step S703.
In step S701, drawing data in which watermark information is embedded in a carrier object of at least one watermark granularity is obtained; the watermark information is embedded into the drawing data based on the watermark embedding method; wherein each watermark granularity corresponds to at least one of the following granularity levels: file level, layer level, block level, entity level.
The drawing data refers to graphic design data in which watermark information is embedded. The drawing data is preferably graphic design data saved based on DWG files.
The carrier object refers to a graphic element with watermark information embedded in drawing data, and comprises an existing graphic element before the watermark information is embedded in the drawing data, and can also comprise an extended graphic element which is added in the drawing data and is specially used for embedding the watermark information. Watermark information is embedded in one or more carrier objects in the drawing data, and the granularity of the object to which the carrier object belongs is the same as or matched with the granularity of the watermark adopted for embedding the corresponding watermark information in the carrier object.
In step S702, watermark configuration information corresponding to the drawing data is determined, where the watermark configuration information includes one or more watermark granularities.
Specifically, the step includes parsing the watermark configuration information to obtain one or more watermark granularities contained therein. In one embodiment, the watermark configuration information comprises an embedding scheme in which one or more watermark granularities are included and a target carrier object in which the embedded watermark information is specified for each watermark granularity. The determining watermark configuration information corresponding to the drawing data comprises the following steps: determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object embedded with the watermark, which corresponds to the specified watermark granularities; the watermark information is embedded into the drawing data by the watermark embedding scheme; and taking one or more specified watermark granularities contained in the embedding scheme as watermark granularities of the watermark configuration information.
Specifically, the method further comprises the following steps: determining whether the drawing data contains watermark configuration information according to file attributes of the drawing data; if the drawing data does not contain watermark configuration information, traversing a database dictionary corresponding to each level of watermark granularity in the drawing data, and identifying embedded watermark information according to attribute information contained in the database dictionary. In implementation, if the watermark information embedding process includes: the watermark configuration information is stored in the file attribute of the drawing data, so that the watermark configuration information can be successfully obtained, embedded watermark information can be directly extracted from database information corresponding to watermark granularity according to the watermark configuration information, and the original watermark information can be identified.
In step S703, for each watermark granularity, embedded watermark information is obtained from database information corresponding to the watermark granularity.
Specifically, for each watermark granularity, acquiring embedded watermark information from database information corresponding to the watermark granularity includes: determining embedded keywords of each watermark granularity; and acquiring embedded watermark information from database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity. The method for acquiring the embedded watermark information from the database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity comprises the following steps: determining a database dictionary corresponding to the watermark granularity; acquiring binary data corresponding to the embedded keywords according to target attributes matched with the database dictionary and the embedded keywords; and analyzing the binary data to obtain the original watermark information embedded based on the embedded key words.
In one embodiment, when one or more watermark granularities are specified by an embedding scheme included in the watermark configuration information, the obtaining, for each watermark granularity, the embedded watermark information from the database information corresponding to the watermark granularity includes: and aiming at each appointed watermark granularity, acquiring watermark information embedded by the target carrier object from database information corresponding to the appointed watermark granularity.
Referring to fig. 8, a flow chart of a preferred embodiment of a watermark extraction method is shown, comprising: s801, a DWG file containing watermarks is obtained. The watermark is embedded according to the watermark embedding method. S802, judging whether the DWG file contains watermark configuration information, if so, executing S803; otherwise, S804 is performed. S803, watermark configuration information is acquired, and watermark information of a watermark embedding scheme of the DWG file is identified according to the watermark configuration information. Specifically, according to watermark granularity of a watermark embedding scheme and embedded keyword identification watermark information, the method comprises the following steps: searching the attribute which is the same as or matched with the embedded keyword in the database dictionary corresponding to the watermark granularity, and extracting the embedded watermark such as binary data according to the attribute value. S804, traversing database information of different levels (such as file level, layer level, block level, entity level and other different granularity levels) contained in the database of the DWG file, and identifying watermark information. S805, extracting watermark content, i.e., original watermark information, from the watermark information.
In one embodiment, when the watermark granularity is at the file level, traversing the database dictionary of the drawing data file, reading the corresponding content from the file attribute identical to or matched with the corresponding embedded key, obtaining the binary data embedded as watermark information, and resolving the original watermark information from the watermark information. Referring to fig. 3 again, for example, the embedded keyword is "author information", the original watermark information is resolved by reading the binary string "0110" included in the author information attribute of the metadata.
In one embodiment, when the granularity of the watermark is the granularity of the layer level, traversing the database dictionary of the layer, reading the corresponding content from the layer attribute which is the same as or matched with the corresponding embedded key, obtaining the binary character string as the embedded watermark, and analyzing the original watermark information. Referring to fig. 4 again, for example, the embedded keywords are "transparency", "frozen state", the transparency of the watermark layer is read, and if the transparency is 3, the corresponding watermark information is "11"; and reading the frozen state of the layer, and if the frozen state is frozen, the watermark information is 1. Of course, other watermark information is also possible, such as: if the transparency value is 0, analyzing the watermark information to be 00; if the transparency is 1, the corresponding watermark information is "01"; the transparency is 2, and the corresponding watermark information is 10; the non-frozen representative watermark information is 0. If the keyword is "embedding invisible layer", the invisible layer can be directly searched through each layer, the binary character strings contained in the database dictionary of the invisible layer are read, and the watermark information is analyzed.
In one embodiment, when the granularity of the watermark is the granularity of the block level, traversing the database dictionary of the block, and reading the block attribute content which is the same as or matched with the embedded key in the block according to the corresponding embedded key to obtain a binary character string and analyze the watermark information. Referring to fig. 5 again, in the figure, the embedded keywords are "proportion" and "rotation angle", and the proportion of the block is read, and the proportion is 1.02, which represents watermark information "10", but may be other values, for example: the scale 1 represents watermark information "00", the scale 1.01 represents watermark information "01", and the scale 1.03 represents watermark information "11". The rotation angle of the block is read, and if the rotation angle is 0, the corresponding watermark information is "00", if the rotation angle is 1, the corresponding watermark information is "01", if the rotation angle is 2, the corresponding watermark information is "10", and if the rotation angle is 1, the corresponding watermark information is "11". If the keyword is 'embedded invisible text box', each block can be directly traversed, the invisible text box is searched, the binary character strings contained in the text box are read, and watermark information is analyzed.
In one embodiment, when the granularity of the watermark is the granularity of the entity level, traversing the database dictionary of the entity, and reading the content corresponding to the entity attribute identical to or matched with the embedded keyword in the entity according to the corresponding embedded keyword to obtain a binary character string and analyze the watermark information. For example, if the embedded keywords are "linear proportion" and "transparency", the linear proportion of the entity is read, the linear proportion is 1 and represents watermark information "00", the linear proportion is 1.01 and represents watermark information "01", the linear proportion is 1.02 and represents watermark information "10", and the linear proportion is 1.03 and represents watermark information "11"; and reading the transparency of the entity, wherein if the transparency is 0, the corresponding watermark information is '0', if the transparency is 1, the corresponding watermark information is '01', and if the transparency is 2, the corresponding watermark information is '10', and if the transparency is 3, the corresponding watermark information is '11'.
The above embodiments may be arbitrarily combined. For example, if watermark information with multiple granularities, such as file ownership, layer designer, block responsible person and entity design implementer, is embedded in drawing data at the same time, all watermarks can be extracted according to the above embodiments.
The watermark information may be a hidden watermark carried by an embedded invisible layer and/or an invisible text box, and correspondingly, the obtaining the embedded watermark information from the database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity includes: if the embedded key words represent that invisible layers are embedded, traversing a layer database dictionary corresponding to the layers to find invisible layers embedded with watermark information, acquiring binary data contained in the invisible layers in the layer database dictionary, and analyzing the binary data to obtain embedded original watermark information; and/or if the embedded keyword represents that the invisible text box is embedded, traversing a block database dictionary corresponding to the block to find the invisible text box embedded with watermark information, reading binary data contained in the invisible text box, and analyzing the binary data to obtain embedded original watermark information.
Thus, the method provided by the embodiment is described, and the method aims at the watermark embedded through the database information of the drawing data, extracts the watermark of one or more different layers such as a file layer, a layer, a block layer, an entity layer and the like according to the watermark configuration information or traversing the database of the drawing data, so that the watermark information can be safely, accurately and stably extracted and identified, the integrity detection of the watermark of no layer can be realized, and the comprehensive copyright protection is performed.
In accordance with the first embodiment, a watermark embedding device is provided in a third embodiment of the present application, and the relevant portions will be referred to in the description of the corresponding method embodiments. The watermark embedding device as shown in fig. 9 includes:
a watermark configuration unit 901, configured to obtain drawing data, watermark configuration information of the drawing data, and watermark information to be embedded into the drawing data;
a configuration parsing unit 902, configured to determine one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level;
the watermark embedding unit 903 is configured to embed watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data.
Optionally, the configuration parsing unit 902 is specifically configured to: determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object to be embedded with the watermark, which corresponds to the specified watermark granularities, and the target carrier object is at least part of one or more levels of a file level, a layer level, a block level and an entity level of the drawing data; taking the designated watermark granularity contained in the embedding scheme as the watermark granularity contained in the watermark configuration information; the watermark embedding unit 903 is specifically configured to: and embedding watermark information corresponding to the specified watermark granularity into the target carrier object corresponding to the drawing data and the specified watermark granularity according to the specified watermark granularity contained in the embedding scheme.
Optionally, the watermark embedding unit 903 is specifically configured to: embedding watermark information corresponding to watermark granularity into existing graphic elements of the drawing data corresponding to the watermark granularity; and/or adding an extended graphic element corresponding to the watermark granularity aiming at the drawing data, and embedding watermark information corresponding to the watermark granularity into the extended graphic element; wherein the existing graphic element and the extended graphic element are the carrier objects.
Optionally, the drawing data is graphic design data stored based on DWG files.
Optionally, the watermark embedding unit 903 is specifically configured to: determining embedded keywords of each watermark granularity; the embedded keywords are keywords preset for watermark granularity or input keywords; for each watermark granularity, watermark information corresponding to the embedded keywords of the watermark granularity is embedded into a carrier object of the drawing data corresponding to the watermark granularity.
Optionally, the watermark embedding unit 903 is specifically configured to: embedding watermark information corresponding to the embedded keywords into database information corresponding to the watermark granularity; the database information stores the carrier object.
Optionally, the watermark embedding unit 903 is specifically configured to: determining target attributes matched with the embedded keywords in a database dictionary corresponding to the watermark granularity; and setting target attributes of the carrier objects in the database dictionary according to the watermark information corresponding to the embedded keywords.
Optionally, the watermark embedding unit 903 is specifically configured to: when the watermark granularity is at the file level, modifying at least one attribute matched with the embedded key words in the file structure, version information and metadata of the drawing data according to watermark information corresponding to the embedded key words of the watermark granularity.
Optionally, the watermark embedding unit 903 is specifically configured to: when the watermark granularity is at the layer level, modifying one or more layer attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or embedding an invisible watermark layer for bearing watermark in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark layer in the form of binary data.
Optionally, the watermark embedding unit 903 is specifically configured to: when the watermark granularity is at the block level, modifying one or more block attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or embedding invisible watermark blocks for bearing watermarks in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark blocks in the form of binary data.
Optionally, the watermark embedding unit 903 is specifically configured to: when the watermark granularity is at an entity level, one or more entity attributes of the drawing data are modified according to watermark information corresponding to the embedded keywords of the watermark granularity.
Optionally, watermark information embedded in the drawing data for different watermark granularities, including the same or different watermark content; and/or each watermark granularity corresponds to one or more embedded keywords.
Optionally, the watermark embedding unit 903 is specifically configured to: and if the embedded keywords are matched with the angle attribute and/or the proportion attribute in the block attribute, modifying the corresponding attribute values within the threshold range so as to realize embedding of the watermark information which is not visible in the vision.
In accordance with the second embodiment, a watermark extraction apparatus is provided in a fourth embodiment of the present application, and the relevant portions will be described with reference to the corresponding method embodiments. The watermark extraction apparatus shown in fig. 10 includes:
A drawing data acquisition unit 1001 for acquiring drawing data in which watermark information is embedded in a carrier object of at least one watermark granularity; the watermark information is embedded into the drawing data based on the watermark embedding method; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level;
A watermark configuration determining unit 1002, configured to determine watermark configuration information corresponding to the drawing data, where the watermark configuration information includes one or more watermark granularities;
Watermark extraction unit 1003 is configured to obtain, for each watermark granularity, embedded watermark information from database information corresponding to the watermark granularity.
Optionally, the watermark configuration determining unit 1002 is specifically configured to: determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object embedded with the watermark, which corresponds to the specified watermark granularities; the watermark information is embedded into the drawing data by the watermark embedding scheme; one or more specified watermark granularities contained in the embedding scheme are used as watermark granularities of the watermark configuration information; the watermark extraction unit 1003 is specifically configured to: and aiming at each appointed watermark granularity, acquiring watermark information embedded by the target carrier object from database information corresponding to the appointed watermark granularity.
Optionally, the drawing data is graphic design data stored based on DWG files.
Optionally, the watermark configuration determining unit 1002 is specifically configured to: determining whether the drawing data contains watermark configuration information according to file attributes of the drawing data; if the drawing data does not contain watermark configuration information, traversing a database dictionary corresponding to each level of watermark granularity in the drawing data, and identifying embedded watermark information according to attribute information contained in the database dictionary.
Optionally, the watermark extraction unit 1003 is specifically configured to: determining embedded keywords of each watermark granularity; and acquiring embedded watermark information from database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity.
Optionally, the watermark extraction unit 1003 is specifically configured to: determining a database dictionary corresponding to the watermark granularity; acquiring binary data corresponding to the embedded keywords according to target attributes matched with the database dictionary and the embedded keywords; and analyzing the binary data to obtain the original watermark information embedded based on the embedded key words.
Optionally, the watermark extraction unit 1003 is specifically configured to: if the embedded key words represent that invisible layers are embedded, traversing a layer database dictionary corresponding to the layers to find invisible layers embedded with watermark information, acquiring binary data contained in the invisible layers in the layer database dictionary, and analyzing the binary data to obtain embedded original watermark information; and/or if the embedded keyword represents that the invisible text box is embedded, traversing a block database dictionary corresponding to the block to find the invisible text box embedded with watermark information, reading binary data contained in the invisible text box, and analyzing the binary data to obtain embedded original watermark information.
Based on the above embodiments, a fifth embodiment of the present application provides an electronic device, and relevant portions may be referred to the corresponding descriptions of the above embodiments. Referring to fig. 11, an electronic device is shown, which includes: a memory, and a processor; the memory is used for storing a computer program, and the computer program is executed by the processor to execute the method provided by the embodiment of the application.
Based on the foregoing embodiments, a sixth embodiment of the present application provides a computer storage medium, and relevant portions thereof should be referred to the corresponding descriptions of the foregoing embodiments. The schematic diagram of the computer storage medium is similar to the schematic diagram of the electronic device, and the memory in the figure can be understood as the storage medium. The computer storage medium stores computer-executable instructions that, when executed by a processor, are configured to implement the methods provided by the embodiments of the present application.
In one typical configuration, the electronic device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory. The memory may include volatile memory in a computer-readable medium, random Access Memory (RAM) and/or nonvolatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.
It will be appreciated by those skilled in the art that 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.
While the application has been described in terms of preferred embodiments, it is not intended to be limiting, but rather, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the spirit and scope of the application as defined by the appended claims.

Claims (24)

1. A method of watermark embedding, comprising:
obtaining drawing data, watermark configuration information of the drawing data and watermark information to be embedded into the drawing data;
Determining one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level;
and embedding watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data.
2. The method of claim 1, wherein said determining one or more watermark granularities comprised by said watermark configuration information comprises:
determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object to be embedded with the watermark, which corresponds to the specified watermark granularities, and the target carrier object is at least part of one or more levels of a file level, a layer level, a block level and an entity level of the drawing data;
Taking the designated watermark granularity contained in the embedding scheme as the watermark granularity contained in the watermark configuration information;
The embedding of watermark information corresponding to watermark granularity into the carrier object corresponding to watermark granularity of the drawing data comprises the following steps:
And embedding watermark information corresponding to the specified watermark granularity into the target carrier object corresponding to the drawing data and the specified watermark granularity according to the specified watermark granularity contained in the embedding scheme.
3. The method according to claim 1, wherein embedding watermark information corresponding to watermark granularity in a carrier object corresponding to watermark granularity of the drawing data comprises:
Embedding watermark information corresponding to watermark granularity into existing graphic elements of the drawing data corresponding to the watermark granularity; and/or the number of the groups of groups,
Adding an extended graphic element corresponding to watermark granularity aiming at the drawing data, and embedding watermark information corresponding to watermark granularity into the extended graphic element;
wherein the existing graphic element and the extended graphic element are the carrier objects.
4. The method of claim 1, wherein the drawing data is graphic design data saved based on a DWG file.
5. The method according to claim 1, wherein embedding watermark information corresponding to watermark granularity in a carrier object of the drawing data corresponding to the watermark granularity comprises:
Determining embedded keywords of each watermark granularity; the embedded keywords are keywords preset for watermark granularity or input keywords;
For each watermark granularity, watermark information corresponding to the embedded keywords of the watermark granularity is embedded into a carrier object of the drawing data corresponding to the watermark granularity.
6. The method of claim 5, wherein embedding watermark information corresponding to the watermark granularity embedded key into a carrier object of the drawing data corresponding to the watermark granularity, comprises:
embedding watermark information corresponding to the embedded keywords into database information corresponding to the watermark granularity; the database information stores the carrier object.
7. The method according to claim 6, wherein embedding watermark information corresponding to the embedded key into database information corresponding to the watermark granularity comprises:
determining target attributes matched with the embedded keywords in a database dictionary corresponding to the watermark granularity;
And setting target attributes of the carrier objects in the database dictionary according to the watermark information corresponding to the embedded keywords.
8. The method according to claim 1, wherein embedding watermark information corresponding to watermark granularity in a carrier object corresponding to watermark granularity of the drawing data comprises:
When the watermark granularity is at the file level, modifying at least one attribute matched with the embedded key words in the file structure, version information and metadata of the drawing data according to watermark information corresponding to the embedded key words of the watermark granularity.
9. The method according to claim 1, wherein embedding watermark information corresponding to watermark granularity in a carrier object corresponding to watermark granularity of the drawing data comprises:
when the granularity of the watermark is at the layer level, then:
Modifying one or more layer attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or the number of the groups of groups,
Embedding an invisible watermark layer for bearing watermark in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark layer in the form of binary data.
10. The method according to claim 1, wherein embedding watermark information corresponding to watermark granularity in a carrier object corresponding to watermark granularity of the drawing data comprises:
When the watermark granularity is at the block level, then:
modifying one or more block attributes of the drawing data according to watermark information corresponding to the embedded keywords of the watermark granularity; and/or the number of the groups of groups,
Embedding invisible watermark blocks for bearing watermarks in the drawing data, and embedding watermark information corresponding to the embedded keywords of the watermark granularity into the watermark blocks in the form of binary data.
11. The method according to claim 1, wherein embedding watermark information corresponding to watermark granularity in a carrier object corresponding to watermark granularity of the drawing data comprises:
When the watermark granularity is at an entity level, one or more entity attributes of the drawing data are modified according to watermark information corresponding to the embedded keywords of the watermark granularity.
12. The method as recited in claim 1, further comprising:
Watermark information embedded in the drawing data for different watermark granularities, including the same or different watermark content; and/or the number of the groups of groups,
Each watermark granularity corresponds to one or more embedded keywords.
13. The method as recited in claim 1, further comprising:
And if the embedded keywords are matched with the angle attribute and/or the proportion attribute in the block attribute, modifying the corresponding attribute values within the threshold range so as to realize embedding of the watermark information which is not visible in the vision.
14. A watermark extraction method, comprising:
obtaining drawing data embedded with watermark information in a carrier object with at least one watermark granularity; wherein the watermark information is embedded in the drawing data based on the method of any one of claims 1-13; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level;
Determining watermark configuration information corresponding to the drawing data, wherein the watermark configuration information comprises one or more watermark granularities;
for each watermark granularity, acquiring embedded watermark information from database information corresponding to the watermark granularity.
15. The method of claim 14, wherein determining watermark configuration information corresponding to the drawing data comprises:
Determining an embedding scheme contained in the watermark configuration information, wherein the embedding scheme contains one or more specified watermark granularities and information of a target carrier object embedded with the watermark, which corresponds to the specified watermark granularities; the watermark information is embedded into the drawing data by the watermark embedding scheme;
One or more specified watermark granularities contained in the embedding scheme are used as watermark granularities of the watermark configuration information;
For each watermark granularity, acquiring embedded watermark information from database information corresponding to the watermark granularity, including:
and aiming at each appointed watermark granularity, acquiring watermark information embedded by the target carrier object from database information corresponding to the appointed watermark granularity.
16. The method of claim 14, wherein the drawing data is graphic design data saved based on a DWG file.
17. The method as recited in claim 14, further comprising:
determining whether the drawing data contains watermark configuration information according to file attributes of the drawing data;
If the drawing data does not contain watermark configuration information, traversing a database dictionary corresponding to each level of watermark granularity in the drawing data, and identifying embedded watermark information according to attribute information contained in the database dictionary.
18. The method according to claim 14, wherein for each watermark granularity, obtaining embedded watermark information from database information corresponding to the watermark granularity comprises:
Determining embedded keywords of each watermark granularity;
And acquiring embedded watermark information from database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity.
19. The method according to claim 18, wherein the obtaining the embedded watermark information from the database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity includes:
determining a database dictionary corresponding to the watermark granularity;
Acquiring binary data corresponding to the embedded keywords according to target attributes matched with the database dictionary and the embedded keywords;
And analyzing the binary data to obtain the original watermark information embedded based on the embedded key words.
20. The method according to claim 18, wherein the obtaining the embedded watermark information from the database information corresponding to the watermark granularity according to the embedded keyword of the watermark granularity includes:
If the embedded key words represent that invisible layers are embedded, traversing a layer database dictionary corresponding to the layers to find invisible layers embedded with watermark information, acquiring binary data contained in the invisible layers in the layer database dictionary, and analyzing the binary data to obtain embedded original watermark information;
And/or the number of the groups of groups,
If the embedded keywords represent that invisible text boxes are embedded, traversing a block database dictionary corresponding to the blocks to find the invisible text boxes embedded with watermark information, reading binary data contained in the invisible text boxes, and analyzing the binary data to obtain embedded original watermark information.
21. A watermark embedding device, comprising:
the watermark configuration unit is used for obtaining drawing data, watermark configuration information of the drawing data and watermark information to be embedded into the drawing data;
A configuration analysis unit, configured to determine one or more watermark granularities contained in the watermark configuration information; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level;
And the watermark embedding unit is used for embedding watermark information corresponding to the watermark granularity into the carrier object corresponding to the watermark granularity of the drawing data.
22. A watermark extraction apparatus, comprising:
A drawing data acquisition unit for acquiring drawing data in which watermark information is embedded in a carrier object of at least one watermark granularity; wherein the watermark information is embedded in the drawing data based on the method of any one of claims 1-13; wherein each watermark granularity corresponds to one of the following granularity levels: file level, layer level, block level, entity level;
A watermark configuration determining unit, configured to determine watermark configuration information corresponding to the drawing data, where the watermark configuration information includes one or more watermark granularities;
The watermark extraction unit is used for acquiring embedded watermark information from database information corresponding to each watermark granularity.
23. An electronic device, comprising:
a memory, and a processor; the memory is adapted to store a computer program which, when executed by the processor, performs the method of any of claims 1-20.
24. A computer storage medium having stored thereon computer executable instructions which when executed by a processor are adapted to carry out the method of any one of claims 1 to 20.
CN202410107475.4A 2024-01-24 2024-01-24 Watermark embedding and watermark extracting methods, devices and equipment Pending CN118014812A (en)

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