TY - CONF T1 - Security of feature extraction in image hashing T2 - Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on Y1 - 2005 A1 - Swaminathan,A. A1 - Mao,Yinian A1 - M. Wu KW - cryptography; KW - differential KW - digital KW - entropy; KW - extraction; KW - feature KW - functions; KW - hash KW - hashing; KW - image KW - metric; KW - processing; KW - randomness; KW - robustness; KW - Security KW - signature; KW - signatures; AB - Security and robustness are two important requirements for image hash functions. We introduce "differential entropy" as a metric to quantify the amount of randomness in image hash functions and to study their security. We present a mathematical framework and derive expressions for the proposed security metric for various common image hashing schemes. Using the proposed security metric, we discuss the trade-offs between security and robustness in image hashing. JA - Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on VL - 2 M3 - 10.1109/ICASSP.2005.1415586 ER -