Image matching between visually protected images with one-time key based phase scrambling

We propose an image matching method using one-time key based phase scrambling. The phase scrambling is used for protection of the original information of templates visually in order to secure privacy. In the proposed method, a key is used to scramble an image once, but the key is not required in the image matching. An appropriately determined key allows image matching for visually protected images without the key. In the previously proposed image matching technique, a key was required for both scrambling and image matching.