Robust hashing model and its use in a real application
E. McCarthy · 2004
An increasing interest in the soft hashing problem has been witnessed in recent times. Soft hashing, also known as robust hashing or perceptual hashing, consists of summarising multimedia data, so as to obtain a concise representation called a hash value. Techniques implementing soft hashing are intended to mirror the behaviour of cryptographic hashing when the information to be hashed can be subject to different kinds of distortions. Many heuristic techniques for undertaking the soft hashing of multimedia data have been devised. Except for some attempts, a framework giving solid guidelines to solve the problem is largely lacking. We provide one possible approach to undertake the modelling of robust soft hashing, detailing the basic problems involved. We present a framework within which established heuristic methods of robust multimedia hashing may be analysed. We show how one prior scheme in particular partly fits inside our model and illustrate how it may be improved.