Section: New Software and Platforms

Lagmeters

Systems to measure end-to-end latency in interactive systems

Keywords: Interaction - Latency

Functional Description: The first 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.

The second method relies on a vibration sensor attached to a finger and a photo-diode to detect the screen response. Both are connected to a micro-controller connected to a host computer using a low-latency USB communication protocol in order to combine software and hardware probes to help determine where the latency comes from. We provide source code and materials to replicate both the hardware and software.

• Participants: Géry Casiez, Nicolas Roussel, Stéphane Huot, Thomas Pietrzak, Sébastien Poulmane, Stéphane Conversy, Damien Marchal and Matthieu Falce

• Partners: Université Lille 1 - Inria

• Contact: Géry Casiez

• Publications: Characterizing Latency in Touch and Button-Equipped Interactive Systems - Looking through the Eye of the Mouse: A Simple Method for Measuring End-to-end Latency using an Optical Mouse

• URL: http://ns.inria.fr/mjolnir/lagmeter/