Multimedia Goes Beyond Content

T o many people in this community, “multimedia” means multiple digitalmedia types, such as audio, images, and video. From audio/visual (AV) media, researchers can extract various AV features—for example, melfrequency cepstral coefficients (MFCC) from audio, color moments from images, or motion vectors from videos—to represent the AV multimedia. Significant research has been done in feature extraction, feature representation, feature fusion, and feature-based indexing and retrieval in the past two decades. Because these AV features are extracted from the raw content of the AV media, they’re also called content features. Generally, these are lowlevel features that can be automatically extracted from the AV media. Because the content features have semantic gaps from human concepts, in the early 2000s, researchers started to introduce context features—such as time, location, exposure parameters, and other metadata—as another type of multimedia. This combination of content and context is called 2C. As a result, the definition of multimedia expanded from just media content to include media context. For example, video motion features, plus the time of the video, are considered multimedia—that is, multiple media. In the late 2000s, social networks became popular. Such networks bring yet another feature dimension—for example, in-link, outlink, degree of friendship, and so on. Many social networks, such as Pinterest and Flickr, include photos and videos, so this once again expands the definition of multimedia. If we refer to social features as connectivity features, then we have the 3C model, which includes content, context, and connectivity. Including connectivity as another media type enables us to process and understand multimedia in a new way. I encourage all readers of—and potential contributors to—IEEE MultiMedia to think about the 3C model. This short message also naturally leads to the introduction of our newest associate editor, Hayley Hung, whose research focus is in the integration of content, context, and connectivity. MM