A Note on "Confidentiality-Preserving Image Search: A Comparative Study Between Homomorphic Encryption and Distance-Preserving Randomization"
This work is incremental, pointing out errors in prior research on confidentiality-preserving image search, which could affect researchers and practitioners in secure data retrieval.
The authors identified flaws in two existing image search schemes by Lu et al., noting that the first scheme does not utilize additive homomorphic encryption as claimed, and the second scheme unnecessarily uses it, suggesting a more efficient symmetric key encryption alternative.
Recently, Lu et al. have proposed two image search schemes based on additive homomorphic encryption [IEEE Access, 2 (2014), 125-141]. We remark that both two schemes are flawed because: (1) the first scheme does not make use of the additive homomorphic property at all; (2) the additive homomorphic encryption in the second scheme is unnecessary and can be replaced by a more efficient symmetric key encryption.