A Multitouch Software Architecture

Florian Echtler and Gudrun Klinker

Technische Universität München

Institut für Informatik

NordiCHI 2008: Using Bridges Hank Wei1

Outline

• Introduction

• Related Work

• A Multitouch Software Architecture

• Implementation

• Discussion

• Conclusion and Future Work

2

Introduction

• Multi-touch Hardware & Software

• Interoperability

• Software Architecture– High-Level API

– Across Hardware

– Standardization

3

Related Work

• Multitouch Interfaces– low-level input processing tools• touchlib

• reacTIVision

• OSC-based TUIO

– high-level interaction software• DiamondTouch

• DiamondSpin

4

Related Work

• Other toolkits– vvvv, Processing, MPX

• Recognize Gestures

5

A Multitouch Software Architecture

• Hardware Abstraction Layer

• Transformation Layer

• Interpretation Layer– Regions

– Events

– Features

• Widget Layer

6

Implementation

• Multitouch Widgets based on OpenGL

• Reconfigurable, Hardware-Independent

• support Gestures (move, scale, rotate)

• Hardware Drivers – for FTIR, DI, Wiimote, DiamondTouch..

• TUIO converters

7

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

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

Comment

• Technology and then Architecture?

• Architecture and then Technology?

• Architecture v.s. Implementation

10

Q&Athanks

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