A fragile watermark generation method and device including coordinate and attribute information

Abstract

The present application relates to the field of geographic information security technology, and in particular to a fragile watermark generation method and device including coordinate and attribute information. The method includes: dividing the minimum bounding rectangle of all interest surfaces of the high-precision map into at least one sub-block according to a preset division method, and calculating the sub-block index value of each sub-block; determining the number of interest surfaces corresponding to each sub-block; determining the first watermark information according to the horizontal coordinate value and the vertical coordinate value of each point of the interest surface; generating a coordinate fragile watermark; splitting the address information of the interest surface into four different levels of sub-addresses according to the address level, and determining the intermediate sub-address corresponding to each sub-address according to the number of characters in each level of sub-address, and the mapping relationship between zero-width characters and binary; obtaining the intermediate address information, and finally obtaining the attribute information fragile watermark. This method can improve the protection of high-precision map data.

Description

Technical Field

[0001] The present application relates to the field of geographic information security technology, and in particular to a fragile watermark generation method and device including coordinate and attribute information. Background Art

[0002] According to actual business needs, high-precision maps can be divided into multiple interest surfaces, each of which is one of the main goals of subsequent business, and the interest surface data is used to describe the relevant information of the interest surface.

[0003] The commercial value and research significance of interest surface data mainly lie in its large amount of geographic coordinates and rich attribute information. With the continuous development of information technology, data security has become increasingly important. The coordinates and attribute information of interest surface data are easily tampered with, which not only destroys the integrity of the data, but also may cause serious trust issues. Therefore, it is particularly urgent to design an effective interest surface data integrity protection algorithm.

[0004] At present, fragile watermarking algorithms are usually used to protect interest surface data. Existing fragile watermarking algorithms focus on protecting the coordinates in interest surface data, ignoring the integrity protection of attribute information, and cannot simultaneously achieve integrity authentication of coordinates and attributes. Therefore, a fragile watermarking algorithm is needed that can simultaneously take into account the integrity authentication of coordinates and attribute information of interest surface data to improve the protection of high-precision map data. Summary of the invention

[0005] The embodiment of the present invention provides a fragile watermark generation method and device including coordinate and attribute information. The fragile watermark generated by the method can simultaneously take into account the integrity authentication of the coordinates and attribute information of the interest surface data, so as to improve the protection of high-precision map data. The embodiment of the present invention provides the following technical solutions:

[0006] According to a preset division method, the minimum bounding rectangle of the fragile watermark generation method for all interest surfaces of the high-precision map including coordinates and attribute information is divided into at least one sub-block, and a sub-block index value of each sub-block is calculated based on the preset division method;

[0007] According to the positional relationship between the center point of each interest surface and each sub-block, the number of interest surfaces corresponding to each sub-block is determined;

[0008] Determine first watermark information according to the abscissa value and the ordinate value of each point of the interest surface;

[0009] Generate a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information;

[0010] Splitting the address information of the interest surface into four different levels of sub-addresses according to the address level, and determining the intermediate sub-address corresponding to each sub-address according to the number of characters in each level of sub-address and the mapping relationship between zero-width characters and binary;

[0011] Based on all the intermediate sub-addresses, the intermediate address information is obtained;

[0012] According to the intermediate address information and the address category corresponding to the interest surface, an attribute information fragile watermark is obtained.

[0013] Specifically, determining the number of interest surfaces corresponding to each sub-block according to the positional relationship between the center point of each interest surface and each sub-block includes:

[0014] When the center point of the interest surface is included in the sub-block, the positional relationship between the interest surface and the sub-block is a containment relationship;

[0015] When the center point of the interest surface falls on the boundary line of multiple sub-blocks, the area of ​​the interest surface falling in each sub-block adjacent to the boundary line is calculated, and the positional relationship between the sub-block with the largest area and the interest surface is an inclusion relationship;

[0016] For each sub-block, the number of interest surfaces whose positional relationship corresponding to the sub-block is a containment relationship is taken as the number of interest surfaces.

[0017] Specifically, determining the first watermark information according to the horizontal coordinate value and the vertical coordinate value of the interest surface includes:

[0018] According to formula (1), the coordinate extraction values ​​corresponding to the horizontal coordinate value and the vertical coordinate value are obtained. ;

[0019] Formula (1)

[0020] Among them, when When is the horizontal coordinate value, is the length of the decimal places of the horizontal coordinate value, Extract the value for the horizontal axis ;when When is the vertical coordinate value, is the length of the decimal places of the ordinate value, Extract the value for the vertical axis ;

[0021] According to the horizontal coordinate extraction value and the vertical coordinate extraction value, the first watermark information is calculated using formula (2): ;

[0022] Formula (2)

[0023] In the formula, is a hash function.

[0024] Specifically, generating a coordinate fragile watermark according to the number of interest surfaces, the sub-block index value, and the first watermark information includes:

[0025] For each interest surface, according to the storage order of each coordinate point in the interest surface:

[0026] Sequentially embedding the first watermark information generated at the previous coordinate point into the third to last decimal place of the horizontal coordinate and the vertical coordinate of the next coordinate point by using the quantization index modulation technology; and,

[0027] Convert the number of the interest surface of the sub-block where the interest surface is located into a binary sequence, and embed it into the second to last decimal place of the horizontal and vertical coordinates of each coordinate point; and,

[0028] Convert the sub-block index value into a binary sequence and embed it into the last decimal place of the horizontal coordinate and the vertical coordinate of each coordinate point;

[0029] The horizontal coordinate and the vertical coordinate after the embedding operation is completed are used as the coordinate fragile watermark.

[0030] Specifically, determining the intermediate sub-address corresponding to each sub-address according to the number of characters of each level of sub-address and the mapping relationship between zero-width characters and binary includes:

[0031] For each sub-address, the zero-width character corresponding to the sub-address is determined according to the mapping relationship between the zero-width character and binary; the intermediate sub-address corresponding to the sub-address is obtained according to formula (3): :

[0032] Formula (3)

[0033] in, To preset the embed location, The first to the second sub-address The characters between the bits, For the The characters between the first and last digits, is the zero-width character corresponding to the subaddress, The number of characters for this subaddress.

[0034] Specifically, the intermediate address information and the address category corresponding to the interest surface are used to obtain a fragile watermark of attribute information, including:

[0035] Convert the address category corresponding to the interest face into a binary sequence, convert the converted binary sequence into an address category sequence constructed by zero-width characters, add the zero-width character sequence to the end of the characters of the address category, and obtain the address category containing the watermark;

[0036] The intermediate address information and the address category containing the watermark are used as the attribute information fragile watermark.

[0037] The embodiment of the present invention further provides a fragile watermark generation device including coordinate and attribute information, the device comprising:

[0038] A first calculation module is used to divide the minimum bounding rectangle of all interest surfaces of the high-precision map into at least one sub-block according to a preset division method, and calculate a sub-block index value of each sub-block based on the preset division method;

[0039] A first determination module is used to determine the number of interest surfaces corresponding to each sub-block according to the positional relationship between the center point of each interest surface and each sub-block;

[0040] A second determination module, configured to determine first watermark information according to a horizontal coordinate value and a vertical coordinate value of each point of the interest surface;

[0041] A first generating module, configured to generate a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information;

[0042] A third determination module is used to split the address information of the interest surface into four sub-addresses of different levels according to the address level, and determine the intermediate sub-address corresponding to each sub-address according to the number of characters of each level of sub-address and the mapping relationship between zero-width characters and binary;

[0043] The second generation module is used to obtain intermediate address information based on all intermediate sub-addresses; and obtain attribute information fragile watermark according to the intermediate address information and the address category corresponding to the interest surface.

[0044] Specifically, the first determining module is specifically configured to: when the center point of the interest surface is included in the sub-block, the positional relationship between the interest surface and the sub-block is a containing relationship;

[0045] When the center point of the interest surface falls on the boundary line of multiple sub-blocks, the area of ​​the interest surface falling in each sub-block adjacent to the boundary line is calculated, and the positional relationship between the sub-block with the largest area and the interest surface is an inclusion relationship;

[0046] For each sub-block, the number of interest surfaces whose positional relationship corresponding to the sub-block is a containment relationship is taken as the number of interest surfaces.

[0047] Specifically, the second determining module is specifically used for:

[0048] According to formula (1), the coordinate extraction values ​​corresponding to the horizontal coordinate value and the vertical coordinate value are obtained. ;

[0049] Formula (1)

[0050] Among them, when When is the horizontal coordinate value, is the length of the decimal places of the horizontal coordinate value, Extract the value for the horizontal axis ;when When is the vertical coordinate value, is the length of the decimal places of the ordinate value, Extract the value for the vertical axis ;

[0051] According to the horizontal axis extraction value and the vertical axis extraction value, the first watermark information is calculated using formula (2): ;

[0052] Formula (2)

[0053] In the formula, is a hash function.

[0054] An embodiment of the present invention also provides an electronic device, which includes a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction is executed by the processor to perform the steps of the above-mentioned fragile watermark generation method including coordinate and attribute information.

[0055] The fragile watermark generation method including coordinate and attribute information provided by the implementation of the present invention embeds the fragile watermark information into the low-significant bits of the coordinates and utilizes the invisibility and concealment of zero-width characters, so that the method can protect the copyright and integrity of the data without perception. Correspondingly, in order to simultaneously realize the tampering detection of the coordinates and attributes in the fragile watermark information generated above and accurately identify the type of tampering, the present application also provides a method for detecting fragile watermarks including coordinate and attribute information. Therefore, the solution provided by the present application can improve the accuracy of high-definition maps. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A flow chart of a method for generating a fragile watermark including coordinate and attribute information provided by an embodiment of the present invention;

[0057] Figure 2A structural diagram of a device for generating a fragile watermark including coordinate and attribute information provided by an embodiment of the present invention DETAILED DESCRIPTION

[0058] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0059] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0060] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0061] The technical solution provided by the embodiment of the present invention can take into account the integrity authentication of the coordinates and attribute information of the interest surface data at the same time, so as to improve the protection of high-precision map data. Figure 1 As shown, an embodiment of the present invention provides a method for generating a fragile watermark including coordinate and attribute information, as follows:

[0062] Step 11: divide the minimum bounding rectangle of all interest surfaces of the high-precision map into at least one sub-block according to a preset division method, and calculate the sub-block index value of each sub-block based on the preset division method; this step specifically includes the following contents:

[0063] Step A: The same high-precision map consists of multiple interest surfaces. First, the minimum enclosing rectangle of all interest surfaces is calculated;

[0064] Step B: divide the minimum bounding rectangle according to a preset division method. For example, the preset division method can divide the minimum bounding rectangle into sub-blocks;

[0065] Step C, according to the preset division method, calculate the sub-block index value of each sub-block. The specific method of this step is:

[0066] For each sub-block, determine the index value according to the preset division method, concatenate the index values, and then convert the decimal to binary sequence to obtain the sub-block index value. , the index value can be obtained according to the preset division method, for example, the preset division method is divided into sub-blocks, that is, (ɑ, β), then the index value is (2, 3), which is "23" after splicing. This 23 is the decimal value after splicing, that is, the sub-block index value .

[0067] In step 11, the center point of the minimum circumscribed rectangle may be stored as a key.

[0068] Step 12, according to the positional relationship between the center point of each interest surface and each sub-block, determine the number of interest surfaces corresponding to each sub-block; the specific process of this step is as follows:

[0069] Calculate the center point of each interest surface separately, and perform the following processing for each interest surface:

[0070] When the center point of the interest surface is included in a sub-block, the positional relationship between the interest surface and the sub-block is a containment relationship;

[0071] When the center point of the interest surface falls on the boundary line of multiple sub-blocks, the area of ​​the interest surface falling in each sub-block adjacent to the boundary line is calculated, and the positional relationship between the sub-block with the largest area and the interest surface is an inclusion relationship.

[0072] For each sub-block, the number of interest surfaces corresponding to the sub-block whose position relationship is a containment relationship is converted from decimal to binary sequence as the number of interest surfaces .

[0073] Step 13, determining the first watermark information according to the horizontal coordinate value and the vertical coordinate value of each point of the interest surface; the specific process of this step is as follows:

[0074] The coordinate values ​​of the points constituting the interest surface are read in sequence according to the storage order of the interest surface coordinates, and then the coordinate extraction values ​​corresponding to the horizontal coordinate value and the vertical coordinate value of each point are obtained according to formula (1). ;

[0075] Formula (1)

[0076] Among them, when When is the horizontal coordinate value, is the length of the decimal places of the horizontal coordinate value, Extract the value for the horizontal axis , can be calculated according to formula (a); when When is the vertical coordinate value, is the length of the decimal places of the ordinate value, Extract the value for the vertical axis , which can be calculated according to formula (b).

[0077] Formula (a)

[0078] Formula (b)

[0079] According to the horizontal coordinate extraction value and the vertical coordinate extraction value, the first watermark information is calculated using formula (2): ;

[0080] Formula (2)

[0081] In the formula, is a hash function.

[0082] Step 14, generating a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information; the specific process of this step includes:

[0083] For each interest surface, according to the storage order of each coordinate point in the interest surface:

[0084] The first watermark information generated by the previous coordinate point is sequentially The quantization index modulation technique is used to embed the third last digit of the abscissa and ordinate of the next coordinate point. In particular, the last point generates embedded into the coordinates of the first point; and,

[0085] The number of interest surfaces in the sub-block where the interest surface is located Converted into a binary sequence and embedded into the second to last decimal place of the horizontal and vertical coordinates of each coordinate point; and,

[0086] The sub-block index value Convert it into a binary sequence and embed it into the last decimal place of the horizontal and vertical coordinates of each coordinate point;

[0087] The horizontal coordinate and the vertical coordinate after the embedding operation is completed are used as the coordinate fragile watermark.

[0088] The above steps 11 to 14 generate a fragile watermark containing coordinate information, namely, a coordinate fragile watermark.

[0089] Step 15: Send the address information of the interested face Four sub-addresses of different levels are split according to the address level, and the intermediate sub-address corresponding to each sub-address is determined according to the number of characters of each sub-address level and the mapping relationship between zero-width characters and binary. This step specifically includes:

[0090] Step 1: Address information for each interest group It is composed of multiple addresses at different levels, such as: Province ,city , Districts and Counties Specific address There are four different levels of sub-addresses. Therefore, the address information is divided into Split to get provincial-level sub-addresses , city-level sub-address , sub-address at the district and county level , the lowest level of specific sub-address ;

[0091] Step 2: Calculate the number of characters in each level of sub-address; for example, provincial-level sub-address The number of characters included in ; Sub-address at city level The number of characters included in , sub-address at the district and county level The number of characters included in , specific sub-address The number of characters included in ;

[0092] Step 3: for each sub-address, determine the zero-width character corresponding to the sub-address according to the mapping relationship table 1 between the zero-width character and binary; and obtain the intermediate sub-address corresponding to the sub-address according to formula (3): :

[0093] Formula (3)

[0094] in, To preset the embed location, The first to the second sub-address The characters between the bits, For the The characters between the first and last digits, is a zero-width character corresponding to the subaddress. The number of characters for this subaddress.

[0095] Table 1

[0096] Binary Sequence Zero-width characters 11 U+200B U+180B 10 U+200B U+FEFF 01 U+180B U+FEFF 00 U+200B U+200B

[0097] Specifically, the four-level sub-addresses are calculated in this step as follows:

[0098] Calculate the provincial sub-address according to formula (4) The intermediate subaddress :

[0099] Formula (4)

[0100] In the formula, To preset the embed location, The first to the last in the provincial address The characters between the bits, For the From Table 1, we can know that the zero-width character corresponding to the sub-address is ;

[0101] Calculate the city-level sub-address according to formula (5) The intermediate subaddress ;

[0102] Formula (5)

[0103] In the formula, To preset the embed location, The first to the second sub-addresses in the city The characters between the bits, For the From Table 1, we can know that the zero-width character corresponding to the sub-address is ;

[0104] Calculate the district-level sub-address according to formula (6): The intermediate subaddress ;

[0105] Formula (6)

[0106] In the formula, is the embedding location, The first to the second sub-addresses in the district level The characters between the bits, For the From Table 1, we can know that the zero-width character corresponding to the sub-address is ;

[0107] Calculate the specific sub-address according to formula (7) The middle sub-land ;

[0108] Formula (7)

[0109] In the formula, To preset the embed location, The first to the second sub-address The characters between the bits, For the From Table 1, we can know that the zero-width character corresponding to the sub-address is ;

[0110] Step 16, based on all the intermediate sub-addresses, obtain the intermediate address information; this step specifically includes:

[0111] The above obtained , , , Splice to get the intermediate address information containing the watermark ;

[0112] Step 17, obtaining the attribute information fragile watermark according to the intermediate address information and the address category corresponding to the interest surface. The specific process of this step includes:

[0113] The address category corresponding to the interest face Convert the binary sequence into a binary sequence, convert the converted binary sequence into an address category sequence constructed by zero-width characters, add the zero-width character sequence to the end of the characters of the address category, and obtain the address category containing the watermark ;

[0114] The intermediate address information and the address category containing the watermark are used as the attribute information fragile watermark.

[0115] In the above process, the process of generating the coordinate fragile watermark and the process of generating the attribute information fragile watermark can be performed in parallel, or the order can be selected according to the situation.

[0116] The above process is a method for generating a fragile watermark including coordinates and attribute information. This method embeds the fragile watermark information into the low-significant bits of the coordinates and utilizes the invisibility and concealment of zero-width characters, so that this method can protect the copyright and integrity of the data without perception.

[0117] Correspondingly, in order to simultaneously detect the tampering of the coordinates and attributes in the fragile watermark information generated above and accurately identify the type of tampering, the present application also provides a method for detecting a fragile watermark including coordinate and attribute information. The process includes detecting the coordinates and attribute information in the fragile watermark information as follows:

[0118] The process of detecting the coordinate watermark in the fragile watermark information is as follows:

[0119] Step I: Read the midpoint of the minimum bounding rectangle of all the faces of interest and divide the minimum bounding rectangle into sub-blocks;

[0120] Step II: Calculate the center point of each interest surface. If the center of the interest surface is in a certain sub-block, it is considered that the interest surface belongs to the sub-block, that is, the positional relationship between the interest surface and the sub-block is a containment relationship. The method for determining the positional relationship refers to step 12.

[0121] Step III: For each sub-block, calculate the number of interest surfaces whose position relationship is a containment relationship corresponding to the sub-block, and convert the number of interest surfaces from decimal to binary sequence to obtain the number of interest surfaces after change ;

[0122] Step IV: According to the above step C, calculate the sub-block index value of each sub-block ;

[0123] Step V: According to the above step 13, the coordinates of the points constituting the interest surface are read in sequence according to the storage order of the coordinates of the interest surface, and the values ​​of the abscissa value and the ordinate value of each point before the last three decimal places are intercepted according to formula (1);

[0124] Step VI: Obtain the horizontal coordinate extraction value according to the above formula (a) and formula (b) and extract the value of the ordinate , and and As the parameter of formula (2), the first watermark information is generated ;

[0125] Step VII: Use quantization index modulation technology to extract the first watermark information on the third last decimal place of the horizontal and vertical coordinates of each point , according to the storage order of the points on the surface of interest, the previous point is and Compare. If the comparison results are the same, the coordinates of the point have not been tampered with. If the comparison results of the horizontal and vertical coordinates are different, the coordinates of the point have been tampered with;

[0126] Step VIII: Use quantization index modulation technology to extract the first watermark information on the second to last decimal place of the horizontal and vertical coordinates of each point, and then generate the extracted watermark of the number of interest surfaces after splicing .contrast and ,If the results are the same, it means that the number of interest surfaces in the block has not changed, otherwise it means that the number of interest surfaces in the block has been tampered with;

[0127] Step IX: Use quantization index modulation technology to extract the first watermark information on the last decimal place of the horizontal and vertical coordinates of each point, and then generate the extracted interest surface index watermark after splicing .contrast and If the results are the same, it means that the block where the interest surface is located has not changed, otherwise it means that the position of the interest surface has been tampered with.

[0128] The process of detecting the attribute information watermark in the fragile watermark information is as follows:

[0129] Step 1: Read the address information in the interest face attribute information and categories ;

[0130] Step 2: Use the address segmentation method to separate the address information Split into provincial sub-addresses , City-level sub-address , District-level sub-address , Specific sub-address Four different levels of subaddresses;

[0131] Step 3: According to formula (4) and Table 1, extract No. Character to Zero-width characters between bit characters are converted into binary sequences according to the mapping relationship. If the extracted binary sequence is not 11 or the zero-width character cannot be extracted, it indicates that the provincial address has been tampered with;

[0132] Step ④: According to formula (5) and Table 1, extract No. Character to Zero-width characters between bit characters are converted into binary sequences according to the mapping relationship. If the extracted binary sequence is not 10 or the zero-width character cannot be extracted, it indicates that the city address has been tampered with;

[0133] Step ⑤: According to formula (6) and Table 1, extract No. Character to Zero-width characters between bit characters are converted into binary sequences according to the mapping relationship. If the extracted binary sequence is not 01 or the zero-width character cannot be extracted, it indicates that the district and county address has been tampered with;

[0134] Step ⑥: According to formula (7) and Table 1, extract No. Character to Zero-width characters between bit characters are converted into binary sequences according to the mapping relationship. If the extracted binary sequence is not 00 or the zero-width character cannot be extracted, it indicates that the specific address has been tampered with;

[0135] Step 7: Categories Convert to binary sequence and extract The trailing zero-width character is converted to a binary sequence. If the converted binary sequence is inconsistent with the binary sequence converted from the zero-width character or the zero-width character cannot be extracted, it indicates that the category has been tampered with.

[0136] The above method for detecting coordinate watermarks in fragile watermark information first generates a fragile watermark according to a method for generating fragile watermarks including coordinate and attribute information, and then compares the generated fragile watermark with the previous fragile watermark, so that the method can simultaneously detect tampering of coordinates and attributes and accurately identify the type of tampering.

[0137] like Figure 2 As shown, an embodiment of the present invention further provides a fragile watermark generation device including coordinate and attribute information, the device comprising:

[0138] A first calculation module 21 is used to divide the minimum bounding rectangle of all interest surfaces of the high-precision map into at least one sub-block according to a preset division method, and calculate a sub-block index value of each sub-block based on the preset division method;

[0139] A first determining module 22, configured to determine the number of interest surfaces corresponding to each sub-block according to the positional relationship between the center point of each interest surface and each sub-block;

[0140] A second determination module 23, configured to determine first watermark information according to the horizontal coordinate value and the vertical coordinate value of each point of the interest surface;

[0141] A first generating module 24, configured to generate a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information;

[0142] The third determination module 25 is used to split the address information of the interest surface into four sub-addresses of different levels according to the address level, and determine the intermediate sub-address corresponding to each sub-address according to the number of characters of each level of sub-address and the mapping relationship between zero-width characters and binary;

[0143] The second generating module 26 is used to obtain the intermediate address information based on all the intermediate sub-addresses; and obtain the attribute information fragile watermark according to the intermediate address information and the address category corresponding to the interest surface.

[0144] The first determining module 22 is specifically configured to: when the center point of the interest surface is included in the sub-block, the positional relationship between the interest surface and the sub-block is a containing relationship;

[0145] When the center point of the interest surface falls on the boundary line of multiple sub-blocks, the area of ​​the interest surface falling in each sub-block adjacent to the boundary line is calculated, and the positional relationship between the sub-block with the largest area and the interest surface is an inclusion relationship;

[0146] For each sub-block, the number of interest surfaces whose positional relationship corresponding to the sub-block is a containment relationship is taken as the number of interest surfaces.

[0147] The second determining module 23 is specifically configured to:

[0148] According to formula (1), the coordinate extraction values ​​corresponding to the horizontal coordinate value and the vertical coordinate value are obtained. ;

[0149] Formula (1)

[0150] Among them, when When is the horizontal coordinate value, is the length of the decimal places of the horizontal coordinate value, Extract the value for the horizontal axis ;when When is the vertical coordinate value, is the length of the decimal places of the ordinate value, Extract the value for the vertical axis ;

[0151] According to the horizontal axis extraction value and the vertical axis extraction value, the first watermark information is calculated using formula (2): ;

[0152] Formula (2)

[0153] In the formula, is a hash function.

[0154] An embodiment of the present invention also provides an electronic device, which includes a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction is executed by the processor to perform the steps of the above-mentioned fragile watermark generation method including coordinate and attribute information.

[0155] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0156] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0157] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0158] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0159] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A fragile watermark generation method including coordinate and attribute information, characterized in that: The method includes: Divide the minimum bounding rectangle of all interest surfaces of the high-precision map into at least one sub-block according to a preset division method, and calculate a sub-block index value of each sub-block based on the preset division method; For each interest surface, when the center point of the interest surface is included in the sub-block, the positional relationship between the interest surface and the sub-block is a containment relationship; when the center point of the interest surface falls on the boundary line of multiple sub-blocks, the area of ​​the interest surface falling in each sub-block adjacent to the boundary line is calculated, and the positional relationship between the sub-block with the largest area and the interest surface is a containment relationship; For each sub-block, the number of interest surfaces whose positional relationship corresponding to the sub-block is a containment relationship is taken as the number of interest surfaces; Determine first watermark information according to the abscissa value and the ordinate value of each point of the interest surface; Generate a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information; Splitting the address information of the interest surface into four different levels of sub-addresses according to the address level, and determining the intermediate sub-address corresponding to each sub-address according to the number of characters in each level of sub-address and the mapping relationship between zero-width characters and binary; Based on all the intermediate sub-addresses, the intermediate address information is obtained; According to the intermediate address information and the address category corresponding to the interest surface, an attribute information fragile watermark is obtained.

2. The method according to claim 1, characterized in that The determining the first watermark information according to the horizontal coordinate value and the vertical coordinate value of the interest surface includes: According to formula (1), a coordinate extraction value value corresponding to the horizontal coordinate value and the vertical coordinate value is obtained; Wherein, when cor is the horizontal coordinate value, len is the length of the decimal places of the horizontal coordinate value, and value is the horizontal coordinate extraction value value x ; When cor is the ordinate value, len is the length of the decimal places of the ordinate value, and value is the ordinate extraction value value y ; According to the horizontal axis extraction value and the vertical axis extraction value, the first watermark information fra is calculated using formula (2) cor ; fra cor = Hash(value x , value y ) mod 2 Formula (2) In the formula, Hash() is a hash function.

3. The method according to claim 1, characterized in that The generating a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information includes: For each interest surface, according to the storage order of each coordinate point in the interest surface: Sequentially embedding the first watermark information generated at the previous coordinate point into the third to last decimal place of the horizontal coordinate and the vertical coordinate of the next coordinate point by using the quantization index modulation technology; and, Convert the number of the interest surface of the sub-block where the interest surface is located into a binary sequence, and embed it into the second to last decimal place of the horizontal and vertical coordinates of each coordinate point; and, Convert the sub-block index value into a binary sequence and embed it into the last decimal place of the horizontal coordinate and the vertical coordinate of each coordinate point; The horizontal coordinate and the vertical coordinate after the embedding operation is completed are used as the coordinate fragile watermark.

4. The method according to claim 1, characterized in that The determining of the intermediate sub-address corresponding to each sub-address according to the number of characters of each level sub-address and the mapping relationship between zero-width characters and binary includes: For each sub-address, the zero-width character corresponding to the sub-address is determined according to the mapping relationship between the zero-width character and binary; the intermediate sub-address address' corresponding to the sub-address is obtained according to formula (3): address′=address[1:σ]+character+address[σ+1:β] Formula (3) Among them, σ is the preset embedding position, address[1:σ] is the character between the first and σth bits in the sub-address, address[σ+1:β] is the character between the σ+1th and the last bit, character is the zero-width character corresponding to the sub-address, and β is the number of characters in the sub-address.

5. The method according to claim 1, characterized in that The intermediate address information and the address category corresponding to the interest surface are used to obtain a fragile watermark of attribute information, including: Convert the address category corresponding to the interest face into a binary sequence, convert the converted binary sequence into an address category sequence constructed by zero-width characters, add the zero-width character sequence to the end of the characters of the address category, and obtain the address category containing the watermark; The intermediate address information and the address category containing the watermark are used as the attribute information fragile watermark.

6. A fragile watermark generation device including coordinate and attribute information, characterized in that: The device includes: A first calculation module is used to divide the minimum bounding rectangle of all interest surfaces of the high-precision map into at least one sub-block according to a preset division method, and calculate a sub-block index value of each sub-block based on the preset division method; The first determination module is used for, for each interest surface, when the center point of the interest surface is included in the sub-block, the positional relationship between the interest surface and the sub-block is a containment relationship; when the center point of the interest surface falls on the boundary line of multiple sub-blocks, the area of ​​the interest surface falling in each sub-block adjacent to the boundary line is calculated, and the positional relationship between the sub-block with the largest area and the interest surface is a containment relationship; for each sub-block, the number of interest surfaces whose positional relationship corresponding to the sub-block is a containment relationship is taken as the number of interest surfaces; A second determination module, configured to determine first watermark information according to a horizontal coordinate value and a vertical coordinate value of each point of the interest surface; A first generating module, configured to generate a coordinate fragile watermark according to the number of the interest surfaces, the sub-block index value, and the first watermark information; A third determination module is used to split the address information of the interest surface into four sub-addresses of different levels according to the address level, and determine the intermediate sub-address corresponding to each sub-address according to the number of characters of each level of sub-address and the mapping relationship between zero-width characters and binary; The second generation module is used to obtain intermediate address information based on all intermediate sub-addresses; and obtain attribute information fragile watermark according to the intermediate address information and the address category corresponding to the interest surface.

7. The device according to claim 6, characterized in that The second determining module is specifically used for: According to formula (1), a coordinate extraction value value corresponding to the horizontal coordinate value and the vertical coordinate value is obtained; Wherein, when cor is the horizontal coordinate value, len is the length of the decimal places of the horizontal coordinate value, and value is the horizontal coordinate extraction value value x ; When cor is the ordinate value, len is the length of the decimal places of the ordinate value, and value is the ordinate extraction value value y ; According to the horizontal axis extraction value and the vertical axis extraction value, the first watermark information fra is calculated using formula (2) cor ; fra cor = Hash(value x , value y ) mod 2 Formula (2) In the formula, Hash() is a hash function.

8. An electronic device, characterized in that: The electronic device includes a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction is executed by the processor to execute the steps of any one of the fragile watermark generation methods including coordinate and attribute information in claims 1-5.

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