Research Article

Zero-Watermarking Algorithm for Medical Image Based on VGG19 Deep Convolution Neural Network

Figure 11

Robustness comparison between the proposed algorithm and two algorithms [25, 26] against four types of local nonlinear geometric attacks. (a) Ripple distortion attack. (b) Extrusion distortion attack. (c) Spherical distortion attack. (d) Rotation distortion attack.
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