%0 Conference Paper %B Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on %D 2005 %T Security of feature extraction in image hashing %A Swaminathan,A. %A Mao,Yinian %A M. Wu %K cryptography; %K differential %K digital %K entropy; %K extraction; %K feature %K functions; %K hash %K hashing; %K image %K metric; %K processing; %K randomness; %K robustness; %K Security %K signature; %K signatures; %X 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. %B Acoustics, Speech, and Signal Processing, 2005. Proceedings. (ICASSP '05). IEEE International Conference on %V 2 %P ii/1041 - ii/1044 Vol. 2 - ii/1041 - ii/1044 Vol. 2 %8 2005/03// %G eng %R 10.1109/ICASSP.2005.1415586