Clifton Forlines

DiamondSpin: an extensible toolkit for around-the-table interaction

DiamondSpin is a toolkit for the efficient prototyping of and experimentation with multi-person, concurrent interfaces for interactive shared displays. In this paper, we identify the fundamental functionality that tabletop user interfaces should embody, then present the toolkits architecture and API. DiamondSpin provides a novel real-time polar to Cartesian transformation engine that has enabled new, around-the-table interaction metaphors to be implemented. DiamondSpin allows arbitrary document positioning and orientation on a tabletop surface. Polygonal tabletop layouts such as rectangular, octagonal, and circular tabletops can easily be constructed. DiamondSpin also supports multiple work areas within the same digital tabletop. Multi-user operations are offered through multi-threaded input event streams, multiple active objects, and multiple concurrent menus. We also discuss insights on tabletop interaction issues we have observed from a set of applications built with DiamondSpin.

Direct-touch vs. mouse input for tabletop displays

We investigate the differences -- in terms of bothquantitative performance and subjective preference -- between direct-touch and mouse input for unimanual andbimanual tasks on tabletop displays. The results of twoexperiments show that for bimanual tasks performed ontabletops, users benefit from direct-touch input. However,our results also indicate that mouse input may be moreappropriate for a single user working on tabletop tasksrequiring only single-point interaction.

Lucid touch: a see-through mobile device

Touch is a compelling input modality for interactive devices; however, touch input on the small screen of a mobile device is problematic because a users fingers occlude the graphical elements he wishes to work with. In this paper, we present LucidTouch, a mobile device that addresses this limitation by allowing the user to control the application by touching the back of the device. The key to making this usable is what we call pseudo-transparency: by overlaying an image of the users hands onto the screen, we create the illusion of the mobile device itself being semi-transparent. This pseudo-transparency allows users to accurately acquire targets while not occluding the screen with their fingers and hand. Lucid Touch also supports multi-touch input, allowing users to operate the device simultaneously with all 10 fingers. We present initial study results that indicate that many users found touching on the back to be preferable to touching on the front, due to reduced occlusion, higher precision, and the ability to make multi-finger input.

Gesture registration, relaxation, and reuse for multi-point direct-touch surfaces

Freehand gestural interaction with direct-touch computation surfaces has been the focus of significant research activity. While many interesting gestural interaction techniques have been proposed, their design has been mostly ad-hoc and has not been presented within a constructive design framework. In this paper, we develop and articulate a set of design principles for constructing - in a systematic and extensible manner - multi-hand gestures on touch surfaces that can sense multiple points and shapes, and can also accommodate conventional point-based input. To illustrate the generality of these design principles, a set of bimanual continuous gestures that embody these principles are developed and explored within a prototype tabletop publishing application. We carried out a user evaluation to assess the usability of these gestures and use the results and observations to suggest future design guidelines.

Sharing and building digital group histories

Organizations, families, institutions evolve a shared culture and history. In this work, we describe a system to facilitate conversation and storytelling about this collective past. Users explore digital archives of shared materials such as photographs, video, and text documents on a tabletop interface. Both the software and the interface encourage natural conversation and reflection. This work is an application of our ongoing research on systems for multiple, co-present users to explore digital collections. In this paper, we present a case study of our own group history along with the software extensions developed for this scenario. These extensions include methods for easily branching off from and returning to previous threads of the exploration, incorporating background contexts that support a variety of view points and flexible story sharing, and supporting the active and passive discovery of relevant information.

Exploring the effects of group size and table size on interactions with tabletop shared-display groupware

Interactive tabletops have been previously proposed and studied in the domain of co-located group applications. However, little fundamental research has been done to explore the issue of size. In this paper we identify a number of size considerations for tabletop design, and present an experiment to explore some of these issues, in particular the effects of group size and table size on the speed at which the task was performed, the distribution of work among group members, issues of shared resources, and user preference for table size. Our findings shed light on (1) how work strategies are affected by group size, (2) how social interaction varies with respect to table size, and (3) how the speed of task performance is influenced by group size but not by table size. In addition, our experiments revealed that for larger groups, designers might need to add additional vertical displays for shared information. This finding opens the door for extending single-display groupware to shared-display groupware settings that involve multiple, shared displays.

Combining and measuring the benefits of bimanual pen and direct-touch interaction on horizontal interfaces

Many research projects have demonstrated the benefits of bimanual interaction for a variety of tasks. When choosing bimanual input, system designers must select the input device that each hand will control. In this paper, we argue for the use of pen and touch two-handed input, and describe an experiment in which users were faster and committed fewer errors using pen and touch input in comparison to using either touch and touch or pen and pen input while performing a representative bimanual task. We present design principles and an application in which we applied our design rationale toward the creation of a learnable set of bimanual, pen and touch input commands.

WeSpace: the design development and deployment of a walk-up and share multi-surface visual collaboration system

We present WeSpace -- a collaborative work space that integrates a large data wall with a multi-user multi-touch table. WeSpace has been developed for a population of scientists who frequently meet in small groups for data exploration and visualization. It provides a low overhead walk-up and share environment for users with their own personal applications and laptops. We present our year-long effort from initial ethnographic studies, to iterations of design, development and user testing, to the current experiences of these scientists carrying out their collaborative research in the WeSpace. We shed light on the utility, the value of the multi-touch table, the manifestation, usage patterns and the changes in their workflow that WeSpace has brought about.

Multi-user interaction using handheld projectors

Recent research on handheld projector interaction has expanded the display and interaction space of handheld devices by projecting information onto the physical environment around the user, but has mainly focused on single-user scenarios. We extend this prior single-user research to co-located multi-user interaction using multiple handheld projectors. We present a set of interaction techniques for supporting co-located collaboration with multiple handheld projectors, and discuss application scenarios enabled by them.

Antialiasing for automultiscopic 3D displays

Introduction For more than a century, the display of threedimensional images has inspired the imagination and ingenuity of engineers and inventors. Automultiscopic displays offer uninhibited viewing (i.e., without glasses) of high-resolution stereoscopic images from arbitrary positions. These displays consist of viewdependent pixels that reveal a different color to the observer based on the viewing angle. View-dependent pixels can be implemented using conventional high-resolution displays and parallax-barriers (Figure 1, left), or lenticular sheets. Although the optical principles of multiview auto-stereoscopy have been known for over a century, it is only recently that displays with increased resolution have made them practical. As a result, 3D television is getting renewed attention with Grundig’s announcement that they will acquire, transmit, and display 3D content during the 2006 soccer world cup. However, automultiscopic displays today have several major drawbacks. First, they are plagued by disturbing aliasing artifacts. Second, the acquisition of artifact-free 3D content is challenging. Photographers, videographers, and professionals in the broadcast and movie industry are unfamiliar with the complex setup required to record 3D content. There are currently no guidelines for multicamera parameters, placement, and post-production processing.