Feature extraction for multimedia analysis

Feature extraction is an essential step for processing of multimedia content semantics. Indeed, it is necessary to extract embedded characteristics from within the audiovisual material in order to further analyze its content and then provide a relevant semantic description. This chapter provides an overview of some of the most frequently used low-level features for image, video, audio and text analysis, including some from the MPEG-7 standard, to describe audiovisual content. It discusses the various aspects one should consider when attempting to use multiple features from various modalities together. In particular, approaches for feature selection and feature fusion will be reported as well as synchronization and co-occurrence issues in the context of our chosen scenario: parental control and content filtering of video.