Speech media, i.e., digital audio and video containing spoken content, has blossomed in recent years. Large collections are accruing on the Internet as well as in private and enterprise settings. This growth has motivated extensive research work on techniques and technologies that facilitate reliable indexing and retrieval. Spoken content retrieval (SCR) requires a combination of audio and speech processing technologies with methods from information retrieval (IR). SCR research initially investigated planned speech structured in document-like units, but has subsequently shifted focus to more informal spoken content produced spontaneously, outside of the studio and in conversational settings.

This survey provides an overview of the field of SCR encompassing component technologies, the relationship of SCR to text IR and automatic speech recognition and user interaction issues. It is aimed at researchers with backgrounds in speech technology or information retrieval who are seeking deeper insight on how these fields are integrated to support research and development addressing the core challenges of SCR.