Implementation and analysis of several keyframe-based browsing interfaces to digital video

In this paper we present a variety of browsing interfaces for digital video information. The six interfaces are implemented on top of Físchlár, an operational recording, indexing, browsing and playback system for broadcast TV programmes. In developing the six browsing interfaces, we have been informed by the various dimensions which can be used to distinguish one interface from another. For this we include layeredness (the number of “layers” of abstraction which can be used in browsing a programme), the provision or omission of temporal information (varying from full timestamp information to nothing at all on time) and visualisation of spatial vs. temporal aspects of the video. After introducing and defining these dimensions we then locate some common browsing interfaces from the literature in this 3-dimensional “space” and then we locate our own six interfaces in this same space. We then present an outline of the interfaces and include some user feedback

Towards a Flexible User-Centred Visual Presentation Approach

Leveraging the power of flexible visual presentations has become an effective way to aid information interpretation, decision making and problem solving. It is indispensable to address the high complexities with visualization problems and relieve the impact from the intrinsic limitations of human cognitive capacity. Addressing these problems raises demanding requirements for information presentation flexibility. However, many existing visualization systems tend to provide weak support for such flexibility due to the issue of closely coupled information representation and presentation in system designs. This issue limits their support for rich presentation options, flexible presentation integration and reusability, and vivid storytelling of data. To help with addressing these problems, issues and requirements, this paper generalizes typical presentation models to provide paradigm level support for achieving presentation flexibility, and identifies key requirements for presentation development to accomplish the flexibility at a system level. With articulating the requirements at both paradigm and system levels, the paper proposes a user-centred process to realize presentation flexibility by meeting both functional and cognitive requirements for information presentation. The proposed theory is validated against a real-world business case and applied to guide the development of a prototypical system, which is demonstrated through a sequence of scenario-driven illustrations

Semantics-based visualization

Visualization is the process of mapping data into visual dimensions to create a visual representation to amplify cognition. Visual representations are essential aids to human cognitive tasks. They are valued to the extent that they provide stable and external reference points upon which dynamic activities and thought processes may be calibrated and upon which models and theories can be tested and confirmed. The active use and manipulation of visual representations makes many complex and intensive cognitive tasks feasible. A visual representation is able to convey relationships among many elements in parallel and provides an individual with directly observable memory. A successful visualization allows the user to gain insight into the data, i.e. to communicate different aspect of the data in an effective way. Even with today’s visualization systems that give the user a considerable control over the visualization process, it can be difficult to produce an effective visualization. To obtain useful results, a user had to know which questions to pose; problems had to be framed in very precise terms. A strategy to improve this situation is to guide the user in the selection of the parameters involved in the visualization. Our research goal is the design of a visualization system that assist the user in the construction of the visualization, by considering the semantic of the data, the semantic of the stages through all the visualization process and the semantic of the external elements affecting the visualization.Presentado en el Encuentro de Tesistas de PostgradoRed de Universidades con Carreras en Informática (RedUNCI

The Use of Embedded Interaction Mechanisms for Low-Level Analysis Tasks

The use of information visualization is a strategy to reduce information overload and cognitive efforts. Interaction mechanisms aid the exploration of data when it is not practical to display all data points in one visual display. This study reports the results of a pilot study. The purpose of the study is to determine what interactive mechanisms are used and how they support a task or set of tasks

What is Interaction for Data Visualization?

International audienceInteraction is fundamental to data visualization, but what "interaction" means in the context of visualization is ambiguous and confusing. We argue that this confusion is due to a lack of consensual definition. To tackle this problem, we start by synthesizing an inclusive view of interaction in the visualization community-including insights from information visualization, visual analytics and scientific visualization, as well as the input of both senior and junior visualization researchers. Once this view takes shape, we look at how interaction is defined in the field of human-computer interaction (HCI). By extracting commonalities and differences between the views of interaction in visualization and in HCI, we synthesize a definition of interaction for visualization. Our definition is meant to be a thinking tool and inspire novel and bolder interaction design practices. We hope that by better understanding what interaction in visualization is and what it can be, we will enrich the quality of interaction in visualization systems and empower those who use them