Fig. 1. Comparison of feature points before and after screening. (a) Feature point overlap; (b) correction results with large error; (c) extraction results of error correction; (d) filtered feature point matching; (e) corrected image; (f) correctly corrected extraction results

Fig. 2. Comparison of encryption image and original image under different keys. (a) (b) (e) Encryption results with the same key and different initial offset values; (c) (d) encryption results with different keys; (f) original image

Fig. 3. Halftone decryption results. (a)(e) Encryption and decryption images of R channel; (b)(f) encryption and decryption images of G channel; (c)(g) encryption and decryption images of B channel; (d)(h) encryption and decryption images after channel fusion

Fig. 4. Extraction results under different key conditions. (a) Sub-block segmentation key has error in R channel; (b) sub-block segmentation key has error in R and G channels; (c) sub-block segmentation key has error in R, B and G channels; (d) initial key has error in R channel; (e) initial key has error in R and G channels; (f) initial key has error in R, B and G channels; (g) sub-block segmentation key has error in R channel and initial key has error in R and G channels; (h) sub-block segmentation key has error in R and G channels and initial key has error in R channel; (i) sub-block segmentation key and initial key has in R, B and G channels

Fig. 5. Zero watermark generation and copyright logo extraction

Fig. 6. Host images and logo images. (a) Baboon; (b) car; (c) Lena; (d) pepper; (e) plane; (f) sailboat; (g) logo

Fig. 7. Lena graph and detection results under non geometric attacks. (a) Gaussian noise (0.05); (b) salt-and-peppers noise (0.05); (c) median filtering (7×7); (d) JPEG compression(10%)

Fig. 8. Geometric correction results and copyright logo. (a)(h) rotate 25°; (b)(i) rotate 50°; (c)(j) rotate 75°; (d)(k) rotate 100°; (e)(l) rotate 125°; (f)(m) rotate 150°; (g)(n) rotate 175°

Fig. 9. Comparative experiment results. (a) Gaussian filtering; (b) salt-and-peppers noise; (c) JPEG compression; (d) median filtering; (e) Gaussian filtering; (f) rotation attack; (g) translation attack; (h) scaling attack

Table 1. Experimental results of false alarm rate

Table 2. Experimental results of non geometric attack (NC)

Table 3. Experimental results of geometric attack (NC)

Table 4. Run time test table