1. A Multitouch Software Architecture Florian Echtler and Gudrun Klinker Technische Universität München Institut für Informatik NordiCHI 2008: Using Bridges Hank Wei 1

2. Outline Introduction Related Work A Multitouch Software Architecture Implementation Discussion Conclusion and Future Work 2

3. Introduction Multi-touch Hardware & Software Interoperability Software Architecture – High-Level API – Across Hardware – Standardization 3

4. Related Work Multitouch Interfaces – low-level input processing tools touchlib reacTIVision OSC-based TUIO – high-level interaction software DiamondTouch DiamondSpin 4

5. Related Work Other toolkits – vvvv, Processing, MPX Recognize Gestures 5

6. A Multitouch Software Architecture Hardware Abstraction Layer Transformation Layer Interpretation Layer – Regions – Events – Features Widget Layer 6

7. Implementation Multitouch Widgets based on OpenGL Reconfigurable, Hardware-Independent support Gestures (move, scale, rotate) Hardware Drivers – for FTIR, DI, Wiimote, DiamondTouch.. TUIO converters 7

8. Discussion Interoperability – Multi-Pointer X (MPX) Latency – layer-to-layer – 100 sample (Hardware-Independent) on laptop – average latency of 2.35 ms, standard deviation of 0.26 ms Use Case – add support for novel input device – create device-independent Multitouch App. 8

9. Conclusion and Future Work Software Architecture which aims to encompass the major common traits of existing multitouch software Standard Library of Gestures Hardware Abstraction Layers for other kinds of input hardware. – e.g., combined optical and acoustic tracking. 9

10. Comment Technology and then Architecture? Architecture and then Technology? Architecture v.s. Implementation 10

11. Q&A thanks 11