Maria da Graça Campos Pimentel

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 individuals 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.

Automatically sharing web experiences through a hyperdocument recommender system

As an approach that applies not only to support user navigation on the Web, recommender systems have been built to assist and augment the natural social process of asking for recommendations from other people. In a typical recommender system, people provide suggestions as inputs, which the system aggregates and directs to appropriate recipients. In some cases, the primary computation is in the aggregation; in others, the value of the system lies in its ability to make good matches between the recommenders and those seeking recommendations.In this paper, we discuss the architectural and design features of WebMemex, a system that (a) provides recommended information based on the captured history of navigation from a list of people well-known to the users --- including the users themselves, (b) allows users to have access from any networked machine, (c) demands user authentication to access the repository of recommendations and (d) allows users to specify when the capture of their history should be performed.

Linking by interacting: a paradigm for authoring hypertext

Authoring hypertext structures has always been a difficult task. The cognitive overhead problem, well known from authors when creating structured hyperdocuments, has been tackled in a variety of forms. In this paper we advocate that capture-based systems should support flexible hypertext structures generated by linking by interacting operations. These include linking by capturing operations — which capture user-interactivity during a live session — and linking by augmenting operations — which allow the captured contents to be extended with complementary operations available outside the live session. We demonstrate how such combination leads to the generation of flexible hypertext structures by presenting our implementation in the educational domain.

Interactive multimedia annotations: enriching and extending content

This paper discusses an approach to the problem of annotating multimedia content. Our approach provides annotation as metadata for indexing retrieval and semantic processing as well as content enrichment. We use an underlying model for structured multimedia descriptions and annotations allowing the establishment of spatial temporal and linking relationships. We discuss aspects related with documents and annotations used to guide the design of an application that allows annotations to be made with pen-based interaction with Tablet PCs. As a result a video stream can be annotated during the capture. The annotation can be further edited extended or played back synchronously.

Structuring interactive TV documents

Interactive video technology is meant to support user-interaction with video in scene objects associated with navigation in video segments and access to text-based metadata. Interactive TV is one of the most important applications of this area, which has required the development of standards, techniques and tools, such as MPEG-4 and MPEG-7, to create, to describe, to deliver and to present interactive content.In this scenario, the structure and organization of documents containing multimedia metadata play an important role. However, the Interactive TV documents structuring and organization has not been properly explored during the development of advanced Interactive TV services.This work presents a model to structure and to organize documents describing Interactive TV programs and its related media objects, as well as the links between them. This model gives support to represent contextual information, and makes possible to use relevant metadata information in order to implement advanced services like object-based searches, in- movie (scenes, frames, in-frame regions) navigation, and personalization. To demonstrate the functionalities of our model, we have developed an application which uses an Interactive TV programs documents descriptions to present information about in-frame video objects.

Revealing the whiteboard to blind students: An inclusive approach to provide mediation in synchronous e-learning activities

Promoting the inclusion of students with disabilities in e-learning systems has brought many challenges for researchers and educators. The use of synchronous communication tools such as interactive whiteboards has been regarded as an obstacle for inclusive education. In this paper, we present the proposal of an inclusive approach to provide blind students with the possibility to participate in live learning sessions with whiteboard software. The approach is based on the provision of accessible textual descriptions by a live mediator. With the accessible descriptions, students are able to navigate through the elements and explore the content of the class using screen readers. The method used for this study consisted of the implementation of a software prototype within a virtual learning environment and a case study with the participation of a blind student in a live distance class. The results from the case study have shown that this approach can be very effective, and may be a starting point to provide blind students with resources they had previously been deprived from. The proof of concept implemented has shown that many further possibilities may be explored to enhance the interaction of blind users with educational content in whiteboards, and further pedagogical approaches can be investigated from this proposal.

An infrastructure for open latent semantic linking

The more the web grows, the harder it is for users to find the information they need. As a result, it is even more difficult to identify when documents are related. To find out that two or more documents are in fact related, users have to navigate by the documents in carry out an analysis about their content. This paper presents an infrastructure allowing the use of latent semantic analysis and open hypermedia concepts in the automatic identification of relationships among web pages. Latent Semantic Analysis has been proposed by the information retrieval community as an attempt to organize automatically text objects into a semantic structure appropriate for matching. In open hypermedia systems, links are managed and stored in a special database, a linkbase, which allows the addition of hypermedia functionality to a document without changing the original structure and format of the document. We first present two complementary link-related efforts: an extensible latent semantic indexing service and an open linkbase service. Leveraging off those efforts, we present an infrastructure that identifying latent semantic links within web repositories and makes them available in an open linkbase. To demonstrate by example the utility of our open infrastructure, we built an application presenting a directory of semantic links extracted from web sites.The more the web grows, the harder it is for users to find the information they need. As a result, it is even more difficult to identify when documents are related. To find out that two or more documents are in fact related, users have to navigate by the documents in carry out an analysis about their content. This paper presents an infrastructure allowing the use of latent semantic analysis and open hypermedia concepts in the automatic identification of relationships among web pages. Latent Semantic Analysis has been proposed by the information retrieval community as an attempt to organize automatically text objects into a semantic structure appropriate for matching. In open hypermedia systems, links are managed and stored in a special database, a linkbase, which allows the addition of hypermedia functionality to a document without changing the original structure and format of the document. We first present two complementary link-related efforts: an extensible latent semantic indexing service and an open linkbase service. Leveraging off those efforts, we present an infrastructure that identifying latent semantic links within web repositories and makes them available in an open linkbase. To demonstrate by example the utility of our open infrastructure, we built an application presenting a directory of semantic links extracted from web sites.

Filteryedping: Design Challenges and User Performance of Dwell-Free Eye Typing

The ability to use the movements of the eyes to write is extremely important for individuals with a severe motor disability. With eye typing, a virtual keyboard is shown on the screen and the user enters text by gazing at the intended keys one at a time. With dwell-based eye typing, a key is selected by continuously gazing at it for a specific amount of time. However, this approach has two possible drawbacks: unwanted selections and slow typing rates. In this study, we propose a dwell-free eye typing technique that filters out unintentionally selected letters from the sequence of letters looked at by the user. It ranks possible words based on their length and frequency of use and suggests them to the user. We evaluated Filteryedping with a series of experiments. First, we recruited participants without disabilities to compare it with another potential dwell-free technique and with a dwell-based eye typing interface. The results indicate it is a fast technique that allows an average of 15.95 words per minute after 100min of typing. Then, we improved the technique through iterative design and evaluation with individuals who have severe motor disabilities. This phase helped to identify and create parameters that allow the technique to be adapted to different users.

A social approach to authoring media annotations

End-user generated content is responsible for the success of several collaborative applications, as it can be noted in the context of the web. The collaborative use of some of these applications is made possible, in many cases, by the availability of annotation features which allow users to include commentaries on each others content. In this paper we first discuss the opportunity of defining vocabularies that allow third-party applications to integrate annotations to end-user generated documents, and present a proposal for such a vocabulary. We then illustrate the usefulness of our proposal by detailing a tool which allows users to add multimedia annotations to end-user generated video content.

Context-aware support in structured documents for interactive-TV

Interactive video technology has demanded the development of standards, techniques and tools to create, deliver and present interactive content and associated metadata. The literature reports on models representing interactive-TV (I-TV) programs – one of the main applications of the interactive video technology; the limitation of such models include: strict hierarchical relationships among media objects, low levels of granularity for metadata, programs and media objects descriptions cannot be separated, objects are not described beyond the frame level, lack of integration with context-aware computing. In this paper, we detail features of our MediaObject model for documents describing I-TV programs that aim to minimize those limitations. We discuss the model by means of an application that is part of our I-TV prototype and by an annotation tool that shows that the model can be applied to other domains.