A Reversible Information Hiding Method for Vector Maps Preserving Direction Relationship

Abstract

The invention provides a reversible information hiding method capable of keeping direction relation for vector maps. The reversible information hiding method comprises the following steps: acquiring vertex coordinates; ordering the vertex coordinates; segmenting the ordered coordinates; calculating borders of the obtained segments; acquiring an extension coordinate sequence of the segments, and embedding watermarks; acquiring the sequence of ordered coordinates containing the watermarks; acquiring the coordinates containing the watermarks; and extracting the watermarks, and carrying out non-destructive recovery. According to the method, vertex coordinates of all coordinate axes are ordered and segmented, embedding capacity is expanded via the boundary coordinates of the segments, embedding parameters are set according to the precision error tolerance of the vector maps, and the relative positions of the vertex coordinates of all the coordinate axes are not changed during watermark embedding by setting a watermark embedding condition, so that the invisibility is relatively high while the original direction relation of the vector maps is kept; moreover, after watermark extraction, initial data of the vector maps are recovered in a non-destructive manner, so that the accurate use of the vector maps can be effectively ensured.

Description

technical field [0001] The invention relates to the fields of geographic information science and information hiding, in particular to a vector map reversible information hiding method maintaining direction relationship. Background technique [0002] With the emergence of the Internet and geographic information processing software, people can disseminate and edit spatial information more quickly and conveniently. At the same time, this also makes vector maps face a series of data security issues such as copyright protection, source tracking, and tampering identification. Vector map information hiding technology is a cutting-edge technology to effectively protect the security of vector map data. It hides secret information, namely watermarks, in it without affecting the usability of vector maps, and uses certain detection methods to hide it when necessary. method to extract. Reversible information hiding technology has the property of recovering original data without distort...

AI Technical Summary

Problems solved by technology

This change in the direction relationship between primitives may attract the attention of a third party, eventually leading to the destruction or illegal acquisition of hidden information.

[0004] To sum up, although people have proposed some reversible information hiding methods for vector maps, trying to restore the original data while transmitting secret information, to ensure the precise use of the original data of vector maps, but these methods do not maintain the relationship between the orientation of the graphics elements. , There are still deficiencies in the realization of information security transmission

In addition, patent application No. 2013102366569, titled "A method for reversible information hiding of vector maps based on LSD plane"; patent authorization announcement No. CN102110281B, titled "A method for embedding and extracting difference-extended watermarks for shape point layer data "; patent authorization announcement number CN101604440B, the Chinese patent document titled "Reversible Watermarking Method for Vector Map Based on Spatial Features" also involves the problem of reversible information hiding of vector maps, but this patent application adopts different methods and cannot keep the graphic elements Directional relationship between

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