The availability of versatile multimedia processing software and the far-reaching coverage of the interconnected networks have facilitated flawless copying and manipulations of digital media. The ever-advancing storage and retrieval technologies also have smoothed the way for large-scale multimedia database applications. However, abuses of these facilities and technologies pose pressing threats to multimedia security management in general, and multimedia copyright protection and content integrity verification in particular. Although cryptography has a long history of application to information and multimedia security, the undesirable characteristic of providing no protection to the media once decrypted has limited the feasibility of its widespread use. For example, an adversary can obtain the decryption key by purchasing a legal copy of the media but then redistributing the decrypted copies of the original.