The effective visual exploration of large and complexly structured, abstract data requires sophisticated and interactive visualization techniques. Development of these techniques is the major discipline in information visualization. On the other hand, visualization of geospatial data is an important topic in cartography. The necessity to combine expertise from both fields has long been commonly recognized. In this paper, some considerations on the combination of arbitrary multivariate data visualizations, focus & context interaction techniques and thematic map displays are discussed that will allow the efficient combination of established techniques from both information visualization and cartography.
The network map of the London underground is often put forward as a good example of information visualisation. Certainly this style of metro map has been adopted in many cities to assist train travellers understand the various routes and network connections. This work reports on a preliminary investigation into the question: Can the metro map metaphor be adapted for effectively displaying more abstract knowledge? Four case studies are described that use the metro map metaphor for presenting abstract, interconnecting "trains of thought". These four case studies include using a metro map to summarise the ideas in a complex thesis, using a metro map to communicate a business plan, using a metro map as navigation aid for Web pages and using a metro map to assist university students understand a course structure. This work discusses the aspects of these abstract metro maps from an information visualisation perspective. Experiences learned from the case studies are used to introduce some issues and guidelines for using this metaphor to help people find their way through more abstract data.
In this paper we discuss the use of models of space in the building of mixed-reality systems. By model of space we mean a geometric or symbolic description associated with a physical space. We outline several types of model that exist, how they are surveyed and authored, how they are represented to the users and how they are supported by middleware and sensors. We show that systems often contain numerous models of space and we discuss the issues in maintaining or reifying assumptions about transformations between models.We illustrate these ideas by describing the implementation of a collaborative mixed-reality system that allows users to experience a museum in three modalities: physically co-located visitor with personal digital assistant guide, virtual reality visitor and web visitor.
Many people work in windowless offices where they are deprived of the sight of their outside environment. With this in mind we created a piece where a view of the surrounding neighborhood is streamed from a camera, through a network, and projected as an ambient display on a blank wall in a hallway of the School of Computer Science and Information Systems (CSIS) at Pace University. We discuss the simile of Plato's cave with relationship to our viewers, and comment on the artistic influences of Claude Monet and Camille Pissarro.
The self-organizing map (SOM) is widely accepted as a data visualization and cluster model for its ability to map high dimensional data in a low dimensional output space according to the data's similar features. However, this mapping process is time consuming and a large amount of iterations are needed in order to increase the accuracy of the data representation. This work describes how to apply the RGB color model to the initialization of the SOM neurons. The major feature is that the distribution of the neurons is closely related to the data distribution during the initialization of SOM. Therefore the iterations are greatly reduced and efficiency and accuracy of SOM are much improved. To evaluate our approach against traditional approaches we have conducted an experiment. The initial results show that the color model based 3-D SOM is very promising in the practical application.
Recently researchers have been interested in non-visual forms of presentation. Sound, touch, smell, as well as vision can be used to depict information. One important medium is sound; it can encode information for the blind or partial sighted, used to display information when it is impossible to use a screen, and the hardware is cheap and widely available. Researchers have investigated sonifying various data sources with different data types and configurations. We present a novel path-based model that can be used to describe each of these different sonifications. In summary, the path dictates the sonification tour, the data is mapped into sound via a transfer function, and the quantity of information being sonified is determined by both the span and how the abstract path is registered to the data.
Numerical modelling of lung behaviour during the respiration cycle is a difficult challenge due to its complex geometry and surrounding environment constraints. This paper presents an approach to simulate a patient's lung motion during inhaling and exhaling based on a continuous media mechanics model and solved with a finite element method. One of the key problems is an adequate lung mesh generation, which is specifically developed in this paper.
This work discusses the relevance of architectural design towards the field of information visualization by showing historical and contemporary examples of built structures with encoded information. This overview should demonstrate that information visualization in three dimensional physical environments was already created throughout the history of architecture, even within different cultures. From these examples some design principles for spatial coding of information will be extracted that can be transferred to the field of information visualization. Additionally architectural principles are related to metaphors from different fields of knowledge.
Visualization of large data sets is a demanding task, especially if different users are interested in different aspects of the same data set. Today's visualization techniques often do not distinguish different aspects and thus visualize all aspects of the data, which leads to overcrowded and cluttered representations. Moreover, users are provided with information irrelevant to them.In this paper we describe an event-based approach for visualizing large data sets. The basic idea is to let users describe interesting aspects of the data by means of events and then adapt the visual representation of the data on occurrence of events. We present a formal description of events, assuming that the data are given in relational form. Furthermore, a model for event-based visualization is developed. A brief overview of an early realization of the model along with first visual results is part of this paper.
We present human figure control software using vision-based human motion capturing. We have already developed core techniques for vision-based human motion tracking and motion synthesis. We have provided the first version software as an open source kit. In this work, we have developed the second version software with modified motion synthesis. Our software consists of the following software: the vision software (includes 2D blob tracking modules and stereo vision module) and the motion synthesis software (includes skeletal structure reconstruction from a limit number of 3D positions, i.e., physically simulated joint position estimator). This software can be employed for many real-virtual applications such as avatar based video conferencing, virtual human control, and 3D game consoles which need the user postures as input. Our software requires the following hardware: more than two firewire cameras for vision processing and more than one PC for vision processing, motion synthesis, and rendering. In our real-virtual system, this software is also employed for virtual object manipulation interface with augmented avatar representation.
The purpose of This work is to demonstrate that a tight dynamical connection may be made between text and interactive visualization imagery. It shows that a bi-directional linkage may be created between the image space of a visualization program and hypertext space so that dynamical image and text representations of a data object are synchronized, thus maintaining the consistency of the visual information and information context. The paper begins with an analysis of the relationship between text and image, drawing upon examples from the history of art. It then discusses how text and imagery may be bound to improve the communication of information. Finally, a simple mapping application is created employing XML, HTML, and scalable vector graphics (SVG) demonstrating these principles.
Originally designed as a messaging application, email is now used for a wide range of functions. Email clients however have not progressed correspondingly to support users with email management. This work describes the design of EzMail, an email visualization tool that runs in conjunction with an email client and creates a multi-view interface to assist with email management. Our primary focus is to group and visualize messages as components of threads to provide contextual information and conversational history. We have developed visualizations for individual messages, message properties, and messages in a thread. Message annotation is incorporated, along with a capability for replying simultaneously to several messages. A small user survey and a user study provided information regarding users' management of their messages and threads, and a comparative evaluation of EzMail with respect to Microsoft Outlook.
Digital transducers, notably amorphous silicon panels, are being used in image guided radiotherapy. Using kilo-voltage X-ray sources panel transducers are providing cone beam volume reconstruction. Theoretical considerations show that even sub-degree skew can result in the wandering of projection points across many detector elements to produce serious blurring of the cone beam reconstruction away from the imaging isocentre. The importance of identifying and correcting transducer skew is highlighted and shown to be of potentially greater importance than mechanical flex. Radiographic imaging of a suspended radio-opaque test object is described for direct characterisation of skew. The results of skew correction by image processing are presented. The use of 'auto-focusing' grey level change detection algorithms in cone beam reconstruction images, following programmed incremental angular transformation of the projection profiles of a 'Rando' anthropomorphic phantom, is shown to have the potential for automating skew correction.
The development of effective user interfaces, appropriate sensors, and information processing techniques for enabling the blind to achieve additional perception of the environment is a relentless challenge confronting HCI and sensor researchers. To address this challenge we have developed a novel 3D vision system that can enable the 3D structure of the immediate environment to be perceived via head mounted stereo video cameras and electro-tactile data gloves without requiring any use of the eyes. The electro-neural vision system (ENVS) works by extracting a depth map from the camera images by measuring the disparity between the stereo images. This range data is then delivered to the fingers via electro-neural stimulation to indicate to the user the range of objects being viewed by the cameras. To interpret this information, the user only has to imagine that the hands are held in the direction viewed by the cameras, with fingers extended, and the amount of stimulation felt by each finger indicates the range of objects in the direction pointed at by each finger. This intuitive means of perceiving the 3D structure of the environment in real time effectively enables the user to navigate the environment without use of the eyes or other blind aids. Experimental results are provided demonstrating the potential that this form of 3D environment perception has at enabling the user to achieve localisation and obstacle avoidance skills without using the eyes.
A distributed PHANToM-based system for collaborative haptic visualization of a VR crank is presented. Physical IDOF crank model providing realistic kinaesthetic sensations of inertia and viscosity is described. Theoretical and experimental kinematic trajectory patterns are compared for the case of cooperative two-arm human movements. Nonvisual visualization applications of the system are discussed.
Large collections of image documents are today accessible via communication networks. Cost effective retrieval of the wanted images needs convenient browsing tools. In this contribution a technique for image selection on the basis of key details is illustrated. The technique is useful for instance for assisted queries to digital artwork collections, tele-sensing images, aerial photographs, astronomic databases, etc. The basic feature of the method is the capability of detecting and locating anyway rotated details with reasonable computational costs. In this work a criterion for proper choice of detail reference points is illustrated.
Public engagement in the planning process in the UK is undergoing rapid change, due to the introduction of revised government legislation and the general migration to e-services. We present a research proposal for the development of the next-generation of public engagement systems based on an understanding of these legislative requirements and the opportunities afforded by emerging methodologies and enabling technologies. We start by outlining the development and current state of public engagement. We then provide an overview of current practice, discuss the factors leading to the current pressures for changes in practice and outline the issues to be addressed. Finally we review current research in the area and provide an outline of our proposal.
One important task that the designer of multi-sensory displays must perform is the comparison of displays designed for the different senses. Comparing designs for different visualisations is difficult enough but comparing a visual display with an auditory display, or haptic display is harder still. Yet the designer of multi-sensory displays would like to make sensible decisions about when to use each modality. This work describes the MS-Taxonomy, a classification of abstract data displays that is general for all senses. This allows the same terminology to be used for describing visualisation, sonification and haptic display designs. The classification of displays is hierarchical and describes multiple levels of abstraction. In software engineering terms the taxonomy allows a designer to consider reuse at both an abstract architectural level and also a more detailed component level. Thus design mappings can be discussed independently of the sensory modality to be used. This allows for exactly the same design to be implemented for each sense and subsequently compared or transferred between modalities.
In this paper, an uncommon use of parallel coordinates is illustrated using the Animator software. Animator is used to plot the parallel coordinates of objects in multi-dimensional space. Subsequently, the Animator software is used to animate the movement of individual objects, in this multi-dimensional space over time. Initial empirical studies of this technique for the visualization of data from Neurophysiological research, multi-dimensional spike train datasets, have shown that the technique is useful. Thus, Animator was developed for public access and is now freely available (including source code) from the Visualization Lab at the University of Plymouth, www.plymouth.ac.uk/infovis.
3D features of urban scenes are the most important basic elements, we present a method for extracting 3D features of urban scenes from ground-based laser range data. We give depth image representation, define vertical and horizontal scanline, and remove the invalid data including trees, cables, fences, cars, passers-by, outlies and so on. We employ local self-adaptive curve fitting to extract line segments from main architecture structures. We introduce virtual feature conception for the first time, which indicates some implying structure features of urban scenes. The approach described in this paper has been implemented and applied to create the reconstruction of urban scenes. Experimental results show it is suitable for not only modern buildings but also classical architectures.
