General Terms Electronic

The widespread use of mobile, personal computing devices, together with recent advances in wireless communication technologies, pose a myriad of new opportunities for leveraging the commerce of digital goods. We envision a novel platform for the free-trade of digital content where ordinary users are allowed to market and resell copies of digital content to neighbors in their wireless devices ’ vicinity. By keeping significant part of the revenues, users are likely to drive the sales for their and copyright holders ’ economic benefit. While the marketing, commitment and, optionally, the download of the content is peer-to-peer, the act of finalizing a transaction, i.e., updating users ’ accounts, is based on a client-server architecture. Transactions among users can be performed off-line, without the immediate assistance of the copyright holder or any central entity, with their integrity being enforced by a cryptographic protocol. Combined with the use of tamper-resistant hardware, the system delivers a simple digital rights management policy, relying on incentive-based mechanisms to sustain the economy. In this paper, we focus on demonstrating the technical feasibility of our ideas. We discuss typical use case scenarios and present a GUI mockup with the interaction steps needed for using most of the system’s functionality. We present the cryptographic protocol used to ensure the integrity of purchase transactions and address the main features of the system from an implementation standpoint. Finally, we anticipate exceptional situations that may arise and show how they are handled in the platform

Watch-and-Comment as a Paradigm toward Ubiquitous Interactive Video Editing

The literature reports research efforts allowing the editing of interactive TV multimedia documents by end-users. In this article we propose complementary contributions relative to end-user generated interactive video, video tagging, and collaboration. In earlier work we proposed the watch-and-comment (WaC) paradigm as the seamless capture of an individual`s comments so that corresponding annotated interactive videos be automatically generated. As a proof of concept, we implemented a prototype application, the WACTOOL, that supports the capture of digital ink and voice comments over individual frames and segments of the video, producing a declarative document that specifies both: different media stream structure and synchronization. In this article, we extend the WaC paradigm in two ways. First, user-video interactions are associated with edit commands and digital ink operations. Second, focusing on collaboration and distribution issues, we employ annotations as simple containers for context information by using them as tags in order to organize, store and distribute information in a P2P-based multimedia capture platform. We highlight the design principles of the watch-and-comment paradigm, and demonstrate related results including the current version of the WACTOOL and its architecture. We also illustrate how an interactive video produced by the WACTOOL can be rendered in an interactive video environment, the Ginga-NCL player, and include results from a preliminary evaluation.FINEPFAPESP[03/13930-4]CAPESCNP

Taking advantage of contextualized interactions while users watch TV

While watching TV, viewers use the remote control to turn the TV set on and off, change channel and volume, to adjust the image and audio settings, etc. Worldwide, research institutes collect information about audience measurement, which can also be used to provide personalization and recommendation services, among others. The interactive digital TV offers viewers the opportunity to interact with interactive applications associated with the broadcast program. Interactive TV infrastructure supports the capture of the user-TV interaction at fine-grained levels. In this paper we propose the capture of all the user interaction with a TV remote control-including short term and instant interactions: we argue that the corresponding captured information can be used to create content pervasively and automatically, and that this content can be used by a wide variety of services, such as audience measurement, personalization and recommendation services. The capture of fine grained data about instant and interval-based interactions also allows the underlying infrastructure to offer services at the same scale, such as annotation services and adaptative applications. We present the main modules of an infrastructure for TV-based services, along with a detailed example of a document used to record the user-remote control interaction. Our approach is evaluated by means of a proof-of-concept prototype which uses the Brazilian Digital TV System, the Ginga-NCL middleware.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)CAPESCNPqConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESPFINEPFinanciadora de Estudos e Projetos (FINEP)MCT/RNP/CTICMinistério da Ciência, Tecnologia e Inovação do Brasil (MCTI