Nuno Guimarães

Annotations as multiple perspectives of video content

This paper describes a video annotation tool based on a new and flexible model, that gives several perspectives over the same video content. The model was designed in a way that allows having multiple views over the same video data, enabling users with different requirements to have the most appropriate interface. These views, video-lenses, highlight a specific aspect of the video content that is being annotated. Annotations are made using a timeline based interface with multiple tracks, where each track corresponds to a given video-lens. The format used to store and exchange the information is the MPEG-7 standard. The annotation tool (VAnnotator) is being developed in the scope of Vizard, an ambitious project that aims to define a new paradigm for video navigation, annotation, editing and retrieval. The Vizard project includes users, both from the production/archiving area and from the consumer electronics area, that help to define and validate the annotation requirements and functionality.

The Integration of Workflow Systems and Collaboration Tools

The design and development of computer support for work environments must consider both the coordination of individual activities and the collaboration that occurs among individuals in organizations. This paper presents our research efforts towards the understanding, design and implementation of a technological framework designated by “augmented work environments”. These efforts build bridges between computational support for formal processes in organizational work (workflow) and computational support for interactive and informal processes (collaborative tools for group facilitation, decision or negotiation).

Hypervideo on the web: models and techniques for video integration

Abstract Hypermedia has proven to be a powerful way to structure and interact with multimedia information. In existing hypermedia frameworks, and particularly on the Web, different media types can be integrated in the same hyper document. Given its unique characteristics, true integration of video requires the definition of a more powerful model, denning the semantic of linking videos and other media, and taking into account its spatial and temporal properties. This paper presents the issues involved with providing hypervideo support on the Web. It reviews related work to derive the requirements for such support. These inform the definition of a hypervideo model, based on the Web hypermedia model, capturing video-specific characteristics. In particular, navigation concepts need to be revised in this richer and more complex context. The notion of link awareness is introduced, and several types denned, to help navigation in hypervideo. To support this model, extensions were made to HTML and tools were developed as extensions to existing Web tools, thus maintaining compatibility with existing documents and Web browsers. Some examples are shown to illustrate its functionality. The system is being used and validated in a project, on interactive multimedia for open and distance learning, where video plays a central role.

Mapping interaction onto media façades

This paper discusses the emergence and need of principles and guidelines for the design of interaction spaces based on media façades, as large public interactive spaces. Media façades, as new architectural creations, are being designed and built all over the world, and possibilities for interaction with individuals and groups of users are being discovered in multiple dimensions. This paper consolidates a number of empirically observed features of current projects and maps these onto a systematic framework of feature domains. We expect the framework to help in conceptualization, analysis and evaluation of current and future designs and to guide the design of the active and interactive solutions

BUILDING RICH USER INTERFACES FOR DIGITAL TALKING BOOKS

This paper presents a framework for the automatic production of Digital Talking Books (DTB). The production process converts existing audio tapes and OCR-based digitalisation of text books into full-featured, multi- synchronised, multimodal digital books. The framework deals with the standardisation processes, media enrichment and User Interface definition. The latter is based on abstract, yet DTB specific, pattern-based UI specifications. This allows the definition of various forms of interaction and presentation, required by the diversity and constraints of targets users (e.g. visually impaired persons) and situations of use (e.g., learning). Balancing the focus of production between personalised, situation-based UI and adaptive ones is also considered. The article also summarises some usability tests on generated DTBs that contributed to the refinement of the framework.

Performances of an optical ruler based on one-dimensional hydrogenated amorphous Si position-sensitive detectors produced using different metal contacts

Abstract The aim of this work is to determine the role of different metal contacts on the performances of one-dimensional thin-film position-sensitive detectors produced by plasma-enhanced chemical vapour deposition, to be used in optical rulers for alignment applications. The device consists on an indium tin oxide/p-i-n structure where the metal contacts used were based on Al, Al + Cu and Ag. The results achieved show that the contact mainly influences the final sensor range by limiting the magnitude of the analogue signals recorded. In spite of soldering problems the Al contact was the contact that lead to better discrimination of the sensor, with a nonlinearity of ± 0.8% and a fall-off parameter of 3.2 × 103 cm−1. The Al + Cu contact also exhibits good performances (nonlinearity, of ±1.1%; fall-off parameter, 1.4 × 10−2cm−1) and should be chosen since it is much easier to solder but requires protection against oxidation. The integration of these sensors on the optical ruler lead to the production of a system with a response time below 0.5 ms, an accuracy better than ±1% and a mechanical precision of better than 0.25 mm in 100 mm, with a full-scale noise below ±0.1%.

Programming time in multimedia user interfaces

The new media types used in advance user interfaces and interactive systems introduce time as a significant variable. This paper addresses the architectural support and programming tools that should be provided to the programmer to manage the time dependencies. The approach considers that the basic models and programming paradigms adopted in the manipulation and management of time should be isomorphic with the spatial models used in existing graphical user interfaces. The paper describes the architectural principles of a toolkit designed to support the construction of user interfaces with temporal characteristics. The Ttoolkit is an extension of an existing graphical user interface toolkit, the Xt toolkit. Its design is presented and a sample application is described.

Evaluating usability improvements by combining visual and audio modalities in the interface

This paper reports the findings of an evaluation of an adaptive multimodal application for reading of rich digital talking books. Results are in accordance with previous studies, indicating no user perceived difference between applications with and without adaptivity. The NASA Task Load Index was also used and showed that users of the adaptive application reported less workload. Results also include a comparison between tasks executed with electronic support and tasks executed with print support, and also what specific features in the interface benefited the most from the use of visual and audio modalities.

Facilitating Analysis and Diagnosis in Organisations

This paper addresses the definition of facilitation techniques to the analysis and diagnosis of organisational problems. Its foundations, the cognitive mapping techniques and a specific organisational development approach, are introduced. Then the contributions of technology to the use and augmentation of these methods are discussed and relevant work is referred. Afterwards FADO, a facilitation tool set is presented. Extensions to the organisational methodology are proposed. The introduction of manipulation and visualisation techniques, algorithms and navigation and query features is explored. The current status is reported and perspectives are drawn.

Generation of crossmedia dynamic learning contexts from iTV

Tendencies in convergence, integration and co-existence of several media technologies are creating new opportunities for the globalization of learning practices. Simultaneously, the lifelong learning phenomena, which will take place in a wide variety of contexts and locations, call for flexible environments. iTV holds a great potential in this scenario, but there is still limited research in terms of cognitive and interaction aspects. This paper presents a new paradigm to generate crossmedia dynamic learning contexts from iTV with the aim to link the mentioned opportunities in flexible, adequate and effective learning contexts. In order to better illustrate this paradigm an iTV system, (e-iTV), was designed. The system generates, via iTV, Crossmedia Online Personalized Learning Environments, also designated as COPLE or web lessons, accessible from several types of devices. The system is prepared to respond to communication needs of the viewers since and allows them to share their web lesson. In practical terms, the e-iTV system uses the TV set, not as the final medium, but as a starting point to new crossmedia dynamic learning and communications contexts. The motivations and goals of this work are presented, followed by a review of related work and concepts and the presentation of the conceptual framework. A description of the analysis, planning, development and evaluation of the e-iTV system is presented based on a specific HCI based model. The paper concludes by opening perspectives for future research and developments.