Abstract

Visualizations leverage the human visual system to support the process of sensemaking, in which information is collected, organized, and analyzed to generate knowledge and inform action. Although most research to date assumes a single-user focus on perceptual and cognitive processes, in practice, sensemaking is often a social process involving parallelization of effort, discussion, and consensus building. Thus, to fully support sensemaking, interactive visualization should also support social interaction. However, the most appropriate collaboration mechanisms for supporting this interaction are not immediately clear. In this article, we present design considerations for asynchronous collaboration in visual analysis environments, highlighting issues of work parallelization, communication, and social organization. These considerations provide a guide for the design and evaluation of collaborative visualization systems.

Web-Based Collaborative Visualization Systems. Clockwise from top-left, Spotfire Decision Site Posters, Wikimapia.org, Swivel.com, Sense.us, and Many-Eyes.com. This paper tours the design space for such systems, indicating design considerations and avenues for future research.

Research Paper

PDF (347K)

Abstract

Tourist maps are essential resources for visitors to an unfamiliar city because they visually highlight landmarks and other points of interest. Yet, hand-designed maps are static representations that cannot adapt to the needs and tastes of the individual tourist. In this paper we present an automated system for designing tourist maps that selects and highlights the information that is most important to tourists. Our system determines the salience of map elements using bottom-up vision-based image analysis and top-down web-based information extraction techniques. It then generates a map that emphasizes the most important elements, using a combination of multiperspective rendering to increase visibility of streets and landmarks, and cartographic generalization techniques such as simplification, deformation, and displacement to emphasize landmarks and de-emphasize less important buildings. We show a number of automatically generated tourist maps of San Francisco and compare them to existing automated and manual approaches.

(left) A digital map of San Francisco from Microsoft Live (www.live.com) marks the location of a few user-chosen landmarks using pushpins. It is impossible for a tourist to recognize buildings without further visual information. (right) A tourist map generated by our system automatically includes contextual landmarks in addition to the category of buildings (i.e. restaurants, shopping, etc.) chosen by the user. Moreover the map depicts building facades so that tourists can more easily identify the buildings.

Research Paper

PDF (14.2M)

Abstract

We present a system for creating and viewing interactive exploded views of complex 3D models. In our approach, a 3D input model is organized into an explosion graph that encodes how parts explode with respect to each other. We present an automatic method for computing explosion graphs that takes into account part hierarchies in the input models and handles common classes of interlocking parts. Our system also includes an interface that allows users to interactively explore our exploded views using both direct controls and higher-level interaction modes.

Exploded view diagram generated by our system. Our system instruments 3D models to enable interactive exploded views. This illustration of a turbine model was automatically computed to expose the user-selected target part labeled in red.

Research Paper

PDF (4.3M)

Video

MOV (75.8M)

Abstract

Selection is a fundamental task in interactive applications, typically performed by clicking or lassoing items of interest. However, users may require more nuanced forms of selection. Selecting regions or attributes may be more important than selecting individual items. Selections may be over dynamic items and selections might be more easily created by relaxing simpler selections (e.g., "select all items like this one"). Creating such selections requires that interfaces model the declarative structure of the selection, not just individually selected items. We present direct manipulation techniques that couple declarative selection queries with a query relaxation engine that enables users to interactively generalize their selections. We apply our selection techniques in both information visualization and graphics editing applications, enabling generalized selection over both static and dynamic interface objects. A controlled study finds that users create more accurate selection queries when using our generalization techniques.

Relaxation of date ranges: an initial query is repeatedly relaxed to generalize the selection. One click selects an incident, two clicks selects the day on which the incident occurred, three clicks selects the entire week, four clicks selects the month.

Research Paper

PDF (585K)

Video

MOV (23.6M)

Abstract

Recovering 3D shape from shading is an ill-posed problem that the visual system can solve only by making use of additional information such as the position of the light source. Previous research has shown that people tend to assume light is above and slightly to the left of the object [Sun and Perona 1998]. We present a study to investigate whether the visual system also assumes the angle between the light direction and the viewing direction. We conducted a shape perception experiment in which subjects estimated surface orientation on smooth, virtual 3D shapes displayed monocularly using local Lambertian shading without cast shadows. We varied the angle between the viewing direction and the light direction within a range +/- 66 deg (above/below), and subjects indicated local surface orientation by rotating a gauge figure to appear normal to the surface [Koenderink et al. 1992]. Observer settings were more accurate and precise when the light was positioned above rather than below the viewpoint. Additionally, errors were minimized when the angle between the light direction and the viewing direction was 20-30 deg. Measurements of surface slant and tilt error support this result. These findings confirm the light-from-above prior and provide evidence that the angle between the viewing direction and the light direction is assumed to be 20-30 deg above the viewpoint.

The shading of an object’s surface depends on the light source direction. The light is directed from the viewpoint in the left image, from 22 deg above the viewpoint in the middle image, and from 44 deg above the viewpoint in the right image. The object is positioned identically in each of the three views. In this paper, we present an experiment designed to test how shape perception is affected by changing the angle of the light direction. We found the lighting used in the center image led to the most accurate estimations of 3D shape.

Research Paper

PDF (2.3M)

Abstract

Existing e-book readers do not do a good job supporting many reading tasks that people perform, as ethnographers report that when reading, people frequently read from multiple display surfaces. In this paper we present our design of a dual-display e-book reader and explore how it can be used to interact with electronic documents. Our design supports embodied interactions like folding, flipping, and fanning for local/lightweight navigation. We also show how mechanisms like Space Filling Thumbnails can use the increased display space to aid global navigation. Lastly, the detachable faces in our design can facilitate inter-document operations and flexible layout of documents in the workspace. Semi-directed interviews with seven users found that dual-displays have the potential to improve the reading experience by supporting several local navigation tasks better than a single display device. Users also identified many reading tasks for which the device would be valuable. Users did not find the embodied interface particularly useful when reading in our controlled lab setting, however.

Our prototype e-book reader in the detached configuration.

Research Paper

PDF (1.7M)

Video

MOV (9.2M)

Abstract

In this paper we investigate the effectiveness of animated transitions between common statistical data graphics such as bar charts, pie charts, and scatter plots. We extend theoretical models of data graphics to include such transitions, introducing a taxonomy of transition types. We then propose design principles for creating effective transitions and illustrate the application of these principles in DynaVis, a visualization system featuring animated data graphics. Two controlled experiments were conducted to assess the efficacy of various transition types, finding that animated transitions can significantly improve graphical perception.

Animating from a scatter plot to a bar chart (replacing a numerical dimension with a categorical dimension). The top path directly interpolates between the starting and ending states. The bottom path is staged: the first stage moves points to their x-coordinates and updates the x-axis to form a dot plot, the second stage morphs the points into bars.

Research Paper

PDF (591K)

Video

MOV (18.5M)

Abstract

This paper presents scented widgets, graphical user interface controls enhanced with embedded visualizations that facilitate navigation in information spaces. We describe design guidelines for adding visual cues to common user interface widgets such as radio buttons, sliders, and combo boxes and contribute a general software framework for applying scented widgets within applications with minimal modifications to existing source code. We provide a number of example applications and describe a controlled experiment which finds that users exploring unfamiliar data make up to twice as many unique discoveries using widgets imbued with social navigation data. However, these differences equalize as familiarity with the data increases.

Widgets with visual information scent cues. Left: Radio buttons with comment counts. Right: Histogram slider with data totals.

Research Paper

PDF (848K)

Abstract

Information visualization leverages the human visual system to support the process of sensemaking, in which information is collected, organized, and analyzed to generate knowledge and inform action. Though most research to date assumes a single-user focus on perceptual and cognitive processes, in practice, sensemaking is often a social process involving parallelization of effort, discussion, and consensus building. This suggests that to fully support sensemaking, interactive visualization should also support social interaction. However, the most appropriate collaboration mechanisms for supporting this interaction are not immediately clear. In this article, we present design considerations for asynchronous collaboration in visual analysis environments, highlighting issues of work parallelization, communication, and social organization. These considerations provide a guide for the design and evaluation of collaborative visualization systems.

Web-Based Collaborative Visualization Systems. Clockwise from top-left, Spotfire Decision Site Posters, Wikimapia.org, Swivel.com, Sense.us, and Many-Eyes.com. This paper tours the design space for such systems, indicating design considerations and avenues for future research.

Research Paper

PDF (692K)

Abstract

Creating high-quality label layouts in a particular visual style is a time-consuming process. Although automated labeling algorithms can aid the layout process, expert design knowledge is required to tune these algorithms so that they produce layouts which meet the designer’s expectations. We propose a system which can learn a label layout style from a single example layout and then apply this style to new labeling problems. Because designers find it much easier to create example layouts than tune algorithmic parameters, our system provides a more natural workflow for graphic designers. We demonstrate that our system is capable of learning a variety of label layout styles from examples.

Examples of labeling styles learned by our system.

Research Paper

PDF (7.6M)

Abstract

We present a system for authoring and viewing interactive cutaway illustrations of complex 3D models using conventions of traditional scientific and technical illustration. Our approach is based on the two key ideas that 1) cuts should respect the geometry of the parts being cut, and 2) cutaway illustrations should support interactive exploration. In our approach, an author instruments a 3D model with auxiliary parameters, which we call “rigging,” that define how cutaways of that structure are formed. We provide an authoring interface that automates most of the rigging process. We also provide a viewing interface that allows viewers to explore rigged models using high-level interactions. In particular, the viewer can just select a set of target structures, and the system will automatically generate a cutaway illustration that exposes those parts. We have tested our system on a variety of CAD and anatomical models, and our results demonstrate that our approach can be used to create and view effective interactive cutaway illustrations for a variety of complex objects with little user effort.

Cutaway views generated by our system. To create these illustrations, we “rigged” 3D models of a disk brake and human neck using the authoring component of our system. The illustrations were then generated automatically from the rigged models to expose user-selected target structures (shown in red).

Research Paper

PDF (14.1M)

Video

MOV (104M)

Abstract

We present a new image-based technique for enhancing the shape and surface details of an object. The input to our system is a small set of photographs taken from a fixed viewpoint, but under varying lighting conditions. For each image we compute a multiscale decomposition based on the bilateral filter and then reconstruct an enhanced image that combines detail information at each scale across all the input images. Our approach does not require any information about light source positions, or camera calibration, and can produce good results with 3 to 5 input images. In addition our system provides a few high-level parameters for controlling the amount of enhancement and does not require pixel-level user input. We show that the bilateral filter is a good choice for our multiscale algorithm because it avoids the halo artifacts commonly associated with the traditional Laplacian image pyramid. We also develop a new scheme for computing our multiscale bilateral decomposition that is simple to implement, fast O(N2 log N) and accurate.

The Multi-Light Image Collection for this chard leaf contains 3 images taken under varying lighting conditions. The shading in each input image reveals different aspects of its shape and surface details. We combine the shading at multiple scales across the input images to generate the enhanced results. The result on the left exaggerates surface details by eliminating shadows, but yields a flat look. The result on the right is less extreme and includes some shadows to increase the perception of depth, at the cost of reducing some visible detail in the shadow regions.

Research Paper

PDF (39.5M)

More Details

Supplemental Materials

Abstract

We present Soft Scissors, an interactive tool for extracting alpha mattes of foreground objects in realtime. We recently proposed a novel offline matting algorithm capable of extracting high-quality mattes for complex foreground objects such as furry animals [Wang and Cohen 2007]. In this paper we both improve the quality of our offline algorithm and give it the ability to incrementally update the matte in an online interactive setting. Our realtime system efficiently estimates foreground color thereby allowing both the matte and the final composite to be revealed instantly as the user roughly paints along the edge of the foreground object. In addition, our system can dynamically adjust the width and boundary conditions of the scissoring paint brush to approximately capture the boundary of the foreground object that lies ahead on the scissor’s path. These advantages in both speed and accuracy create the first interactive tool for high quality image matting and compositing.

Our system computes a high quality matte (a) and a novel composite (b) in realtime as the user roughly paints the foreground boundary. Our system makes is easy to create new composites (c) very quickly.

Research Paper

PDF (5.3M)

Video

MP4 (80.1M)

Abstract

We present a framework for automatically enhancing videos of a static scene using a few photographs of the same scene. For example, our system can transfer photographic qualities such as high resolution, high dynamic range and better lighting from the photographs to the video. Additionally, the user can quickly modify the video by editing only a few still images of the scene. Finally, our system allows a user to remove unwanted objects and camera shake from the video. These capabilities are enabled by two technical contributions presented in this paper. First, we make several improvements to a state-of-the-art multiview stereo algorithm in order to compute view-dependent depths using video, photographs, and structure-from-motion data. Second, we present a novel image-based rendering algorithm that can re-render the input video using the appearance of the photographs while preserving certain temporal dynamics such as specularities and dynamic scene lighting.

Some of the video enhancements produced by our system. Given a low quality video of a static scene (top row) and a few high quality photographs of the scene, our system can automatically produce a variety of video enhancements (bottom row). Enhancements include the transfer of photographic qualities such as high resolution, high dynamic range, and better exposure from photographs to video. The video can also be edited in a variety of ways (e.g., object touchup, object removal) by simply editing a few photographs or video frames.

Research Paper

PDF (19.1M)

Video

MOV (51.3M)
YouTube

Abstract

This paper describes mechanisms for asynchronous collaboration in the context of information visualization, recasting visualizations as not just analytic tools, but social spaces. We contribute the design and implementation of sense.us, a web site supporting asynchronous collaboration across a variety of visualization types. The site supports view sharing, discussion, graphical annotation, and social navigation and includes novel interaction elements. We report the results of user studies of the system, observing emergent patterns of social data analysis, including cycles of observation and hypothesis, and the complementary roles of social navigation and data-driven exploration.

The sense.us collaborative visualization system. (a) An interactive visualization applet, with a graphical annotation for the currently selected comment. The visualization is a stacked time-series visualization of the U.S. labor force, broken down by gender. Here the percentage of the work force in military jobs is shown. (b) A set of graphical annotation tools. (c) A bookmark trail of saved views. (d) Text-entry field for adding comments. Bookmarks can be dragged onto the text field to add a link to that view in the comment. (e) Threaded comments attached to the current view. (f) URL for the current state of the application. The URL is updated automatically as the visualization state changes.

Research Paper

PDF (998K)

Video Figure

Flash (20M)