Figure 4
Security of the ToF-CUP camera against two types of decryption attacks.
(a) Cross-correlation coefficients between the image decrypted using the correct decryption key and images using 50 brute force attacks with wrong pseudo-random binary masks. (b) 3D datacube of letters “W” and “U” decrypted using the correct decryption key. (c) As in (b), but using an invalid decryption key in the brute force attack (trial #26). (d) Cross-correlation coefficients between the reconstructed image decrypted using the correct decryption key and each image using a part of the correct decryption key with a different horizontal shift. Positive shift pixel numbers mean the key was shifted to the right of the acquired image, while negative numbers mean a shift to the left. The inset shows the relative positions of the letters “W” and “U” and the full decryption key (green). The part of the decryption key used in the shift security test is marked in purple. (e) As in (b) and (c), but using a part of the correct decryption key right shifted by one encoded pixel.
