Tamper localization of the medical images based on fragile watermarking

For 2D vector maps, obtaining high tamper localization accuracy without requiring extra space is a technically challenging problem. Using an adaptive group division approach and an improved reversible data hiding approach, the author proposes a reversible fragile watermarking method for locating tampered Polylines/Polygons in 2D vector maps. In particular, the author adaptively divide the features of the vector map into groups according to a predefined threshold, calculate an authentication watermark for each group, embed the watermark using the improved reversible data hiding approach, and hide the mark of each feature into the feature itself. Since the adaptive group division method and the improved reversible data hiding method are combined in an attempt to make full use of the watermark embedding space, superior tamper localization accuracy and original content recovery can be ensured. Besides, no extra space is required by hiding the mark of each feature. Experimental results have been provided to demonstrate the effectiveness of our method.

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A New Fragile Watermarking Based on Chaos

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.401-403.1772 ◽

2013 ◽

Vol 401-403 ◽

pp. 1772-1775

Author(s):

Hui Fen Huang

Keyword(s):

Good Practice ◽

Chaotic Sequence ◽

Fragile Watermarking ◽

Image Feature ◽

Original Image ◽

Content Authentication ◽

Tamper Localization ◽

Image Block ◽

Positioning Accuracy ◽

Security Issues

For existing airspace fragile authentication watermarking algorithm positioning accuracy and security issues, this paper presents a fully-fragile watermarking based on chaos for the integrity of the image content authentication and tamper localization. The algorithm uses the original image block, the calculation of each pixel in the image block high-bit gray value as the image feature watermark information. The chaotic sequence is encrypted and determines the position of the watermark bit is embedded watermark information, tampering with the positioning accuracy of an image block of 2 × 2 pixels. Experimental results show that the algorithm is simple, safe, with good practice.

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Semi-Fragile Watermarking with Tamper Localization and Recovery using AMBTC Method

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.e9263.069520 ◽

2020 ◽

Vol 9 (5) ◽

pp. 54-59

Keyword(s):

Digital Media ◽

Extraction Process ◽

Fragile Watermarking ◽

Discrete Wavelet ◽

Tamper Localization ◽

Absolute Moment ◽

Media Communication ◽

Value Decomposition ◽

Watermarking Scheme

The watermarking scheme in digital media communication has become an essential tool in helping content creators prove ownership if any dispute arises in copyright infringement. In this paper, Discrete Wavelet Transform (DWT) and Singular Value Decomposition (SVD) is performed in the watermarking process which improves the authentication of the image and the detection of the tampered region. The semi-fragile watermarking scheme provides robustness to the watermark during extraction process even after the unintentional compression attacks like JPEG compression. The watermark payload is significantly lowered in order to increase the quality of the image. The recovery is done using the absolute moment block truncation coding (AMBTC) of the image in the untampered region. Thus, both the mean and first absolute moment are used in recovering the tampered regions in the watermarked image.

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