Pupil Lab’s mobile eye-tracking glasses: A guide to buying and using

by Lauren Fink, M.Phil., M.Sc.

Buying:

I spent a lot of time deliberating about how I wanted to use mobile eye-tracking glasses and what I needed them to be able to do. Here are some things that helped me in my deliberation process that you might consider doing:

• Read through Pupil Lab’s online documentation.
• Download Pupil Capture and Pupil Player (the software for recording and viewing the eye-tracking data, respectively). You won’t be able to do much with these applications without your glasses but you can get a sense of the user interface and what is possible.
• Email the Pupil Labs sales team. Will, from the team, promptly answered all of my questions. I sent him over 10 emails and each time he was polite and helpful.
• Follow the discussions Pupil Labs glasses users are having on Discord
• Wacth the issue thread on the Pupil Labs github page. This is probably only necessary if you plan to dig in to the Pupil Capture or Pupil Player code.

Because I am interested in mobile eye-tracking during musical situations, I was particularly concerned with how easy it would be to capture and synchronize both audio and video data. While the Pupil Labs glasses do not have a microphone to record on-going audio signals, the Pupil Capture software does have an option to record audio. You can use your computer’s microphone or an external microphone to record audio alongside your eye-tracking and worldview data in Pupil Capture. I will be using the Blue Yeti Pro USB microphone to record audio, rather than my computer’s mic, but depending on your situation and how clean you need the recorded audio to be, there are definitely cheaper/free options.

I am also interested in eye-tracking two people simultaneously. Because I have different use cases and a very limited research budget, I ultimately decided to buy one pair of binocular glasses (with only one camera mounted) and one pair of monocular classes (with one camera mounted). With this combination, I can either track two different people monocularly OR move the eye camera from the monocular frames over to the binocular frames and track one person binocularly. Please note that the binocular frames have mounts and cabling for two cameras, whereas as the monocular frames only have mounts and cabling for one camera. This unfortunately means, that in the future I could buy another eye camera and permanantly have a binocular pair of glasses, but the monocular glasses can never be upgraded to binocular.

How mobile is mobile?

Note that the eye-tracking glasses must be connected to a laptop running Pupil Capture to work. This limits mobility, though there are certainly work-arounds (e.g. a laptop in a backpack), depending on your situation. If greater and lighter mobility is a big consideration for you, note that Pupil Labs recently released a Pupil Mobile app for Android devices, e.g. the Nexus 6p. Here is a short video outlining this feature. As the Pupil Labs website states, headsets with the 3d world camera will not work with Pupil Mobile, so be sure to take this into account when deciding which cameras to buy.

Using:

1. If you haven’t already, download and install the latest release of all Pupil Labs software packages (linked in the second bullet point above). For new users, this is all you need!

   If you plan on developing the code, you can clone it from the Pupil Labs git repository. If you’re unfamiliar with cloning a reposity, you can follow these steps. If you’re entirely unfamiliar with git, try getting started with this guide.

more coming soon …!