Diogo Cabral

• Ph.D
• Senior Researcher at University of Lisbon

Tablet computers provide a natural support for digital annotation associated to any type of media, including live video. However, annotations of live video require real-time motion tracking, maintaining the association between annotations and moving objects, as well as interfaces that facilitate the annotation task of a live event. This work presen...

The manipulation of video content is still a difficult task due to its complexity and richness. This paper applies pen-based technology to video editing, with the goal to improve such interaction. In this research, digital ink is replaced by video content, aiming to provide a more familiar and creative interaction for video editing and to study how...

Exploratory search confront users with challenges in expressing search intents as the current search interfaces require investigating result listings to identify search directions, iterative typing, and reformulating queries. We present the design of Exploration Wall, a touch-based search user interface that allows incremental exploration and sense...

Pen computing or pen-based technology can be considered one of the most natural and intuitive computer input interface for humans. The combination of digital video and pen-based technology can support a new approach for electronic paper by associating handwritten notes and drawings with video segments. This paper presents a proposal for pen-based v...

When using a tablet computer, sketching is a natural approach for users to annotate video scenes. However, when these annotations are done in real-time and overlaid in the video, their context can be lost due to changes in the scene being annotated. We propose an approach towards maintaining the annotations' context, by using object tracking to cre...

Long-term stress is associated with a decline in global health, affecting social, intellectual, and economic development alike. Although comprehensive action plans have been implemented to provide people access to mental health services and promote mental well-being, employees’ mental health generally takes second place to productivity and profit i...

The widespread use of digital cameras in mobile phones has led to an increase in the number of pictures captured and shared. However, the development of interfaces for visualizing image collections has not matched that growth. Most search methods are based on text descriptions and retrieve a large number of results on thumbnail 2D grids, which can...

This paper introduces a design framework for mixed reality urban exploration (MRUE), based on a concrete implementation in a historical city. The framework integrates different modalities, such as virtual reality (VR), augmented reality (AR), and haptics-audio interfaces, as well as advanced features such as personalized recommendations, social exp...

The growth of Internet-distributed TV services has transformed video consumption, enhancing the level of control that viewers have over what they watch. Along with the release of entire seasons of programming at once, this has led to the phenomenon of ‘binge-watching’, in which several episodes of a program are viewed in one sitting. This article p...

Bimanual interactions using pen and touch are natural to humans and have proven and explored in previous research. However, most of the previous work has been limited to using cartesian coordinates of fingers and pen tip. In this work, we go further by exploring additional pen data, like pressure and tilt, combined with multi-touch inputs. We apply...

Today, technology offers exciting and news possibilities to bring visitors closer to museums. The museological universe has developed a lot over the last years, presenting today with innovative characteristics thanks to the digital realms, losing the characteristics of traditional and static museums. As a result of this development, the requirement...

The popularity of internet-distributed TV entertainment services, such as Netflix, has transformed TV consumption behavior. Currently, the level of control viewers have over their TV experiences, along with the release of complete seasons at once, are some of the factors that stimulate the so-called binge-watching phenomenon (the consumption of sev...

Several interaction methods for smart glasses have been studied, but it is not clear which method could be the best to interact with augmented objects. In this study, an Augmented Reality (AR) marker-based application for smart glasses was developed, implementing three different interaction methods for marker selection: one using mid-air hand gestu...

Long-term stress is a leading cause of global health loss. Despite its clear influence on productivity, and overall social and economic development, mental health continues to be neglected in work environments. To help reduce this problem, we present LightStress, a tangible affective artifact that adapts itself to the user's needs in order to impro...

User interface software and technologies have been evolving significantly and rapidly. This poster presents a breakthrough user experience that leverages multisensorial priming and embedded interaction and introduces an interactive piece of furniture called Sense.Seat. Sensory stimuli such as calm colors, lavender and other scents as well as ambien...

Smell is a strong trigger of memories and creativity. Different smells can create sensitive environments that can foster creative tasks. In this paper, we present CreaSenses, a study that includes olfactory cues, representing different types of sensitive environments such as "food" and "ambience" in a within-subject design. Our aim was to obtain a...

In this paper, we discuss how different multimodal implementations are not limited to support creativity but go further by enrich it. While sensory feedback can trigger memories and promote novel associations within an immersive context or space, different input methods can foster fluid interactions that allow to explore different paths and solutio...

While ordinary touchscreen-based interfaces on urban explorer applications draw much of a user's attention onto the screen, visual and audio-haptic augmented reality interfaces have emerged as the two main streams for enabling direct focus on the surroundings. However, neither interface alone satisfies users in the highly dynamic urban environment....

Humans perceive different objects, scenes or places using all their senses. Our sensory richness also plays an important role for creative activities. Humans also recall those sensory experiences in order to spark creativity, e.g. while writing a text. This paper presents a study with 100 students, divided in groups, that explores the effect of aud...

Surface computing allows flexible search interaction where users can manipulate the representation of entities recommended for them to create new queries or augment existing queries by taking advantage of increased screen estate and almost physical tactile interaction. We demonstrate a search system based on 1) Direct Manipulation of Entity Represe...

Collaborative idea generation leverages social interactions and knowledge sharing to spark diverse associations and produce creative ideas. Information exploration systems expand the current context by suggesting novel but related concepts. In this paper we introduce InspirationWall, an unobtrusive display that leverages speech recognition and info...

The user's understanding of information needs and the information available in the data collection can evolve during an exploratory search session. Search systems tailored for well-defined narrow search tasks may be suboptimal for exploratory search where the user can sequentially refine the expressions of her information needs and explore alternat...

Following the proliferation of Augmented Reality technologies and applications in mobile devices it is becoming clear that AR techniques have matured and are ready to be used for large audiences. This poses several new multimedia interaction and usability problems that need to be identified and studied. AR problems are no longer exclusively about r...

Events play an important role in touristic activities, they are usually planned in group, involving collaborative behaviours. Mobile technology is a useful tool for such activities. Augmented reality used in handheld devices can enhance the tourist experience. In this work, we present three mobile apps for the exploration of cultural events in a ci...

Due the growth of video sharing, its manipulation is important, however still a hard task. In order to improve it, this work proposes a pen-based approach, called VideoInk. The concept exploits the painting metaphor, replacing digital ink with video frames. The method allows the user to paint video content in a canvas, which works as a two dimensio...

This paper discusses the evaluation of a video annotator that supports multimodal annotation and is applied to contemporary dance as a creation tool. The Creation-Tool was conceived and designed to assist the creative processes of choreographers and dance performers, functioning as a digital notebook for personal annotations. The prototype, develop...

This paper presents a video annotator that supports multimodal annotation and is applied to contemporary dance as a creation tool. The Creation-Tool was conceived and designed to assist the creative processes of choreographers, working as a digital notebook for personal annotations. The prototype, developed for Tablet PCs, is a real-time multimodal...

This paper presents a video annotator that supports multimodal annotation and is applied to contemporary dance as a creation tool. The prototype, developed for Tablet PCs, explores bimanual interaction, using pen and touch input interfaces. This combination can be more natural and familiar than the traditional input interfaces (keyboard or mouse)....

This paper describes work on projects for supporting active learning processes, using different technologies, including mobile access. The infrastructure is provided by the VideoStore project, a Web system to store, transmit, search and share the contents of courses captured in video. VideoStore involves video interfaces, video annotation, streamin...

This paper describes the current status of the VideoStore project. This project has the goal of developing a Web based system to store, transmit, search, and share the contents of courses captured in video. The current version includes a stable version of the architecture, and a set of advanced interfaces. The application synchronizes video streami...

This paper describes the VideoStore project that has the goal of developing a Web based system to store, transmit, search, and share the contents of courses captured in video. The access will be done using PCs or PDAs for parts of the content, in a wireless broadband network environment. The project is initially tested with contents from courses of...