[Retracted] Robust and Secure Zero-Watermarking Algorithm for Medical Images Based on Harris-SURF-DCT and Chaotic Map

Figure 6

Some test medical images: (a) Brain. (b) Lung. (c) Spine. (d) Abdomen. (e) Elbow. (f) Orbits. (g) Knee. (h) Coronary Artery. (i) Wrist.

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