In the last decade, substantial progress has been made in multimedia creation, transmission, presentation and analysis to facilitate the development of large-scale multimedia information systems. Together with the maturation and deployment of semantic web technologies, it is now possible to build a new generation of multimedia applications that enables large-scale semantic representation, analysis, and delivery of multimedia data from heterogeneous data sources. However, there is still a long way to go for mature solutions of multimedia database systems that are capable of processing semantics-rich, large-volume of multimedia data. It could be even more challenging if such systems are under stringent functional and nonfunctional(e.g., QoS) requirements. The goal of this special issue is to invite high quality scientific contributions in multimedia data semantics, with a focus on how to apply semantic technologies to the acquisition, generation, transmission, storage, processing, and retrieval of large-scale multimedia information. Discussions on future challenges in multimedia information
processing, as well as practical solutions for the design and implementation of multimedia database software systems have also been encouraged. The topics of interest include, but are not limited to, practical areas that span both semantic technologies and multimedia processing and computing. This special issue follows the very successful IEEE International Workshop on Data Semantics for Multimedia Systems and Applications (IEEE-DSMSA) held in 2009 and for which the best authors were invited to submit extended versions of their papers. An open call has been also issued resulting in a very diverse pool of twenty four (24) submissions, well spread around the world since the contact authors were from Austria (1), Belgium (1), Brazil (1), China (1), Finland (1), France (1), Germany (2), India (2), Ireland (2), Italy (1), Japan (1), Netherlands (1), Poland (1), Portugal (1), South Korean (1), Taiwan (2), Tunisia (1), United Kingdom (1) and United States (2). Due to the interdisciplinary nature of the Call for Paper, the papers represented a wide range of approaches and scenarios that have in common the area of multimedia data semantics. All the papers were reviewed by at least three experts. We have carefully selected reviewers with track record publications and review experiences in the particular sub-area. The guest editors have sent out more than 100 review invitations and most of the invited reviewers finished their reviews on time. We are very grateful to the reviewers for their excellent job. In addition, the guest editors examined the reviews for each paper and extended discussions were performed among the organizers and reviewers to reach a consensus for each paper. In the end, six (6) papers were recommended for acceptance. These papers can be split equally into two main topics: semantic multimedia analysis and interaction and evaluation of semantic multimedia. The key ideas and contributions of these papers are summarized as below.