Authors:
Danila Glazkov
1
;
2
;
Nikolay Chupshev
1
;
2
and
Victor Fedoseev
1
;
2
Affiliations:
1
Samara National Research University, Samara, Russia
;
2
Samara-Informsputnik JSC, Samara, Russia
Keyword(s):
Mapbox Vector Tiles, MVT, Geospatial Data, GIS, Geospatial Data Protection, Watermarking, QIM.
Abstract:
The paper proposes a watermarking method for protecting geodata presented in the Mapbox Vector Tile (MVT) format against theft. MVT is an open format that is gaining popularity in web mapping services due to efficient storage and fast rendering. However, the vector nature of the format makes it an easy target for attackers who want to steal data and use in their services. The method proposed in this paper protects MVT data with a digital watermark based on re-quantization of point coordinates of object geometry. The method can be adjusted using a number of parameters that allow finding a balance between the robustness of the digital watermark to map distortions and the error introduced when embedding. A series of experiments performed showed the robustness of this method to several distortions: removal of some objects and layers, reduction in the number of points of existing objects, addition of new objects, controlled shift of points in the tile geometry. With a proper choice of the
watermark parameters, even with a moderate level of each of the listed distortions, which does not lead to a loss of significance of the protected geodata, the method can reach 100% watermark extraction accuracy of all bits of the built-in watermark.
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