摘要：Digital image collections are expanding day by day, and image
retrieval becomes even harder. Both individuals and institutions
encounter serious problems when building their image archives and
later when retrieving the archived images. Visual information cannot be fully expressed in words and normally depends on intuitive human
perception. Consequently, this causes us to find the plain text-based
information inadequate, and as a result, increases the value of the
visual content. However describing, storing and retrieving the visual
content is not simple. The research activities in this area, which
escalated in the 90’s, have brought several solutions to the understanding,
design and development of the image retrieval systems. This
article reviews the studies on image retrieval systems in general, and
content-based image retrieval systems specifically. The article also
examines the features of content-based image retrieval systems.
关键词：Content-based image retrieval, Image retrieval, Visual
information retrieval.
