Vector geospatial data digital watermark method based on DFT coefficient combination

A spatial data and digital watermarking technology, applied in image data processing, image data processing, instruments, etc., can solve problems such as error and original data influence
CN108765253AActive Publication Date: 2018-11-06HUNAN UNIV OF SCI & TECH
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Patent Information

Authority / Receiving Office
CN ยท China
Patent Type
Applications(China)
Current Assignee / Owner
HUNAN UNIV OF SCI & TECH
Publication Date
2018-11-06

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Abstract

The invention discloses a vector geospatial data digital watermark method based on DFT coefficient combination. The method comprises steps that the watermark information is generated; a map is taken as an object, and a watermark carrier model is established based on the DFT coefficient combination polynomial; the map object is taken as a unit, the watermark information is modulated into each map object based on the established watermark carrier model; the watermark information is extracted for verification. The method is advantaged in that based on the DFT coefficient combination polynomial ofa geometric object feature point set, the classical quantization index modulation method is utilized to modulate the watermark information into each DFT coefficient of the polynomial, so watermark intensity is distributed to multiple coefficients, without reducing robustness of the algorithm, watermark invisibility is effectively improved, and the high fidelity of the data is achieved.
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Description

technical field

[0001] The invention relates to a watermarking method, in particular to a digital watermarking method for vector geospatial data based on DFT coefficient combination. Background technique

[0002] Vector geospatial data digital watermarking technology, as the preferred solution to the problem of spatial data copyright protection, has aroused the interest of many scholars at home and abroad.

[0003] From the analysis of the embedding position of the watermark, the robust watermarking algorithms for vector geospatial data are mainly divided into the following categories: (1) The watermark information is hidden in the vertex coordinates. Modify the least significant bit of the vertex coordinates to embed the watermark or combine the watermark bits behind the vertex coordinate bits; in order to resist compression or simplification attacks, the watermark information is embedded in the feature points of the geometric figure. (2) The watermark information is hidde...

Claims

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