ABSTRACT
This chapter reviews the state of the art in the design of content-based fingerprinting (CF) algorithms. It addresses important issues and discusses areas that need further attention for future research. The chapter examines several key components of a CF system, including popular preprocessing of input signals, feature extraction from input signals, postprocessing of features, as well as fingerprint generation and associated postprocessing techniques. It also discusses how the finger-prints should be compared against each other and how the performance of CF algorithms should be evaluated. The chapter explains the common preprocessing algorithms applied to input images and video signals. Leading high-tech companies such as YouTube, Facebook, and Flickr have greatly benefited from this new source of revenue. Text-based search is perhaps the most basic approach, where based on specific keyword a database of multimedia assets is searched for the relevant copies.
