摘要：For quite some time, libraries, document and historical centers from opposite corners of the world have been the caretakers of our rich and assorted social legacy. They have protected and furnished access to the testimonies of knowledge, beauty and inspiration, such as sculptures, paintings, music and literature. The new information technologies have created unbelievable opportunities to make this common heritage more accessible for all. Culture is following the digital path and “memory institutions” are adapting the way in which they communicate with their public. Multimedia technologies have recently created the conditions for a true revolution in the cultural heritage area, with reference to the study, valorization, and fruition of artistic works. New multimedia technologies shall be able to be utilized to plan unique approaches to the perception and fulfillment of the masterful legacy, for instance, through smart cultural objects and new interfaces with the backing of items such as story-telling, gaming and learning. All the plurality of masterpieces (paintings, books, manuscripts, even photos of sculptures and architecture) can be effectively embedded into a unique ``paradigm'' through digitization. This allows a significant reduction in costs, an enormous expansion of public accessibility (and therefore income), and at the same time a tremendous freedom for data elaboration. In brief, digitization enhances pleasure for the public and usefulness to experts on cultural heritage assets. This special issue was organized following the success of the First International Workshop on Multimedia for Cultural Heritage (MM4CH 2011) which was held on May 2011 in Modena, Italy, with the aim of creating a profitable informal working day to discuss hot topics in multimedia, with specific application to cultural heritage. After the workshop an open call for paper was distributed and we collected 18 submission, of which 7 were extended versions of the originating workshop. After two rounds of review 11 papers were accepted for the special issue, 8 as full papers and 3 as case studies. Papers have been contributed from many countries (USA, Italy, Czech Republic, Switzerland, Greece, Brazil) showing the universal importance of cultural heritage. The paper by Rakthanmanon et.al. introduces an efficient and scalable system that can detect approximately repeated occurrences of shape patterns both within and between historical texts. They show that this ability to find repeated shapes allows automatic annotation of manuscripts, and allows users to trace the evolution of ideas. The paper by Schindler and Dellaert instead uses computer vision techniques to tie together large sets of historical photographs of a given city into a consistent 4D model of the city: a 3D model with time as an additional dimension. Larue et.al. introduce a novel approach intended to simplify the production of multimedia content from real objects for the purpose of knowledge sharing, which is particularly appropriate to the cultural heritage field. Cultural Heritage is not just made by visual archives (such as manuscripts or photographs), but also by audio and music resources. The paper by Montecchio et.al. presents a comprehensive methodology for automatic music identification, whose main application is to provide tools to enrich and validate the descriptors of recordings digitized by a sound archive institution. Nouza et.al. describe a software platform that for the automatic transcription and indexation of the Czech Radio archive of spoken documents. The archive contains more than 100.000 hours of audio recordings covering almost ninety years of public broadcasting. In the context of two relevant examples of intangible cultural heritages, such as music and theater, Baratè et.al. present an approach to online fruition of live performances, encoding information with an extension of the international standard IEEE 1599. One of the key elements in multimedia systems is the ability to also search information by data content, and the two papers closing the full paper section del exactly with this problem. The paper by Roman-Rangel et.al. presents recent advancements made towards the design of an efficient content-based retrieval engine for epigraphic versions of Maya hieroglyphs. They describe a systematic study to assess the quality of recently proposed techniques to represent and retrieve images, together with an effective simplified formulation of the HOOSC descriptor that improves the retrieval performance. Kollia et.al. present a new semantic search methodology, including a query answering mechanism which meets the semantics of users’ queries and enriches the answers by exploiting appropriate visual features through an interweaved knowledge and machine learning based approach. An experimental study is presented, using content from the Europeana digital library. Three case studies complete the Special Issue: Mendes et.al. present the development of an effective web-based 3D visualization system whose architecture offers an easy and fast interactivity with 3D models even when limited computer resources are available, adopted in the Universidade Federal do Parana (UFPR) in Brazil, providing an important tool to promote research, educational, social and cultural activities. The paper by Stanco et.al. present a real-time interaction system for ancient artifacts digitally restored in a virtual environment. Using commercial hardware and open source software, Augmented Reality versions of archaeological artifacts are made accessible on mobile devices. The case study for this project is represented by two artifacts of Syracuse, Italy, a statue and an altar, dated back to Hellenistic time. Finally Agosti and Orio report on a study on user requirements carried out on two groups of users: domain specialized users (professional researchers). A digital archive of illuminated manuscripts has been used as a case study for recollecting user requirements. The relations between these two outcomes provide relevant insights on the role of digital resources for the study and dissemination of cultural heritage. We would like to thank the authors for their hard work in the preparation and revision of the manuscripts and for their high quality contributions. We also owe deep gratitude to the MM4CH 2011 program committee members and to the additional reviewers for the effort they put in selecting the best works and for the demanding requirements and thorough comments which strongly improved many papers. Last, but not least, our thanks go to the Editorial Board of the Journal of Multimedia for the exceptional effort they did throughout this process. We hope that you will enjoy reading this special issue.
关键词：Special Issue;Multimedia for Cultural Heritage
