Stéphane Huot

TapTap and MagStick: improving one-handed target acquisition on small touch-screens

We present the design and evaluation of TapTap and MagStick, two thumb interaction techniques for target acquisition on mobile devices with small touch-screens. These two techniques address all the issues raised by the selection of targets with the thumb on small tactile screens: screen accessibility, visual occlusion and accuracy. A controlled experiment shows that TapTap and MagStick allow the selection of targets in all areas of the screen in a fast and accurate way. They were found to be faster than four previous techniques except Direct Touch which, although faster, is too error prone. They also provided the best error rate of all tested techniques. Finally the paper also provides a comprehensive study of various techniques for thumb based touch-screen target selection.

BiTouch and BiPad: designing bimanual interaction for hand-held tablets

Despite the demonstrated benefits of bimanual interaction, most tablets use just one hand for interaction, to free the other for support. In a preliminary study, we identified five holds that permit simultaneous support and interaction, and noted that users frequently change position to combat fatigue. We then designed the BiTouch design space, which introduces a support function in the kinematic chain model for interacting with hand-held tablets, and developed BiPad, a toolkit for creating bimanual tablet interaction with the thumb or the fingers of the supporting hand. We ran a controlled experiment to explore how tablet orientation and hand position affect three novel techniques: bimanual taps, gestures and chords. Bimanual taps outperformed our one-handed control condition in both landscape and portrait orientations; bimanual chords and gestures in portrait mode only; and thumbs outperformed fingers, but were more tiring and less stable. Together, BiTouch and BiPad offer new opportunities for designing bimanual interaction on hand-held tablets.

Multisurface Interaction in the WILD Room

The WILD (wall-sized interaction with large datasets) room serves as a testbed for exploring the next generation of interactive systems by distributing interaction across diverse computing devices, enabling multiple users to easily and seamlessly create, share, and manipulate digital content. The featured Web extra is a video of Michel Beaudouin-Lafon and his colleagues demonstrating how the WILD (wall-sized interaction with large datasets) room lets users view, explore, manipulate large amounts of digital content.

Arpège: learning multitouch chord gestures vocabularies

This paper presents Arpège, a progressive multitouch input technique for learning chords, as well as a robust recognizer and guidelines for building large chord vocabularies. Experiment one validated our design guidelines and suggests implications for designing vocabularies, i.e. users prefer relaxed to tense chords, chords with fewer fingers and chords with fewer tense fingers. Experiment two demonstrated that users can learn and remember a large chord vocabulary with both Arpège and cheat sheets, and Arpège encourages the creation of effective mmnemonics.

Using rhythmic patterns as an input method

While interaction techniques that use the temporal dimension have been used for a long time, such as multiple clicks or spring-loaded widgets, more advanced uses of rhythmic patterns have received little attention in HCI. Using such temporal structures to convey information can be particularly useful in situations where the visual channel is overloaded or even not available. In this paper we introduce Rhythmic Interaction as the use of rhythms for input. We report the results of two experiments that show that (i) rhythmic patterns can be efficiently reproduced by novice users and recognized by computer algorithms, and (ii) rhythmic patterns can be memorized as efficiently as traditional shortcuts when associating them with visual commands. Overall, these results demonstrate the potential of Rhythmic Interaction and open the way to a richer repertoire of interaction techniques.

ArchMenu et ThumbMenu: contrôler son dispositif mobile « sur le pouce »

We introduce in this paper a new kind of menus that are adapted to the interaction with small handheld devices with a tactile screen (PDA, smartphone…) in mobility conditions. With such devices, interaction is often based on standard WIMP paradigms that have been designed for desktop PCs. This approach does not take the specificities of mobility into account and thus limits the capabilities of such devices. We propose two new menu techniques, ArchMenu and ThumbMenu, that are specifically designed to fit the constraints of handheld devices (size and input mode) in mobility conditions.

Looking through the Eye of the Mouse: A Simple Method for Measuring End-to-end Latency using an Optical Mouse

We present a simple method for measuring end-to-end latency in graphical user interfaces. The method works with most optical mice and allows accurate and real time latency measures up to 5 times per second. In addition, the technique allows easy insertion of probes at different places in the system I.e. mouse events listeners - to investigate the sources of latency. After presenting the measurement method and our methodology, we detail the measures we performed on different systems, toolkits and applications. Results show that latency is affected by the operating system and system load. Substantial differences are found between C++/GLUT and C++/Qt or Java/Swing implementations, as well as between web browsers.

Opening polyhedral compiler's black box

While compilers offer a fair trade-off between productivity and executable performance in single-threaded execution, their optimizations remain fragile when addressing compute-intensive code for parallel architectures with deep memory hierarchies. Moreover, these optimizations operate as black boxes, impenetrable for the user, leaving them with no alternative to time-consuming and error-prone manual optimization in cases where an imprecise cost model or a weak analysis resulted in a bad optimization decision. To address this issue, we propose a technique allowing to automatically translate an arbitrary polyhedral optimization, used internally by loop-level optimization frameworks of several modern compilers, into a sequence of comprehensible syntactic transformations as long as this optimization focuses on scheduling loop iterations. This approach opens the black box of the polyhedral frameworks, enabling users to examine, refine, replay and even design complex optimizations semi-automatically in partnership with the compiler.

GlideCursor: pointing with an inertial cursor

Pointing on large displays with an indirect, relative pointing device such as a touchpad often requires clutching. This article introduces gliding, where the cursor continues to move during the clutching gestures. The effect is that of controlling the cursor as a detached object that can be pushed, with inertia and friction similar to a puck being pushed on a table. We analyze gliding from a practical and a theoretical perspective and report on two studies. The first controlled experiment establishes that gliding reduces clutching and can improve pointing performance for large distances. We introduce cursor efficiency to capture the effects of gliding on clutching. The second experiment demonstrates that participants use gliding even when an efficient acceleration function lets them perform the task without it, without degrading performance.

FlowStates: prototypage d'applications interactives avec des flots de données et des machines à états

This article introduces FlowStates, a user interface toolkit compatible with Java Swing that combines two models for managing events: dataflow and state machines. The dataflow model makes it easy to support non-standard input devices and to reconfigure interactions according to the available devices, while state machines support the programming of complex interactions. The article illustrates the power and expressivity of this hybrid approach and the flexibility afforded by the explicit decision to not set strict limits between the roles of each model.