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Support for GazePoint eye-tracker GP3

eyetracking

#1

Hi all, I’m considering to purchase a GP3 eye-tracker by GazePoint ($700). I see there is some code supporting these eye-trackers but I don’t how complete and how reliable this code is. It would be great to hear other people’s experience.

Best wishes, Titus


#2

Hi Titus,

Apologies for late reply. I helped in incorporating the GP3 into the ioHub libraries a couple of years ago now. As for how stable the code is, it is as stable as anything else that has been incorporated into ioHub. The developer of ioHub, Sol Simpson, helped me with the coding. However there are few points you need to know.

Firstly the code will work with original GP3 eyetracker, Gazepoint have developed a new GP3 HD eyetracker, I have no idea if the code will work with new device.

You will absolutely need a computer that has a minimum spec of at least an intel i5 processor.

The GP3 has a sampling speed of 60 Hz, and claims to be accurate to 0.5 - 1 degree of visual angle. I found this to be the case only under absolute optimal conditions.

The calibration is not incorporated into ioHub, so you will have to use the app that comes with the GP3 to calibrate it first, then go into psychopy.

Hope this helps.
Martin


#3

Hi, thanks for the response. I decided to order a GP3 for testing but my understanding is that GP3-HD should work the same because it’s using the same API.

You will absolutely need a computer that has a minimum spec of at least an intel i5 processor.

Good to know. Can you tell where the bulk of the processing cost is incurred? Is it the software that’s talking to the eye-tracker or does it happen in psychopy?

The GP3 has a sampling speed of 60 Hz, and claims to be accurate to 0.5 - 1 degree of visual angle. I found this to be the case only under absolute optimal conditions.

Yeah, these numbers sound very optimistic and you can be happy if you achieve this precision with a much more expensive EyeLink 1000 system. I expect much poorer accuracy but in my application that’s okay. I’m more worried about latencies.

The calibration is not incorporated into ioHub, so you will have to use the app that comes with the GP3 to calibrate it first, then go into psychopy.

That’s unfortunate but according to the documentation of GazePoint’s Open Gaze API, it should be relatively easy to trigger the calibration programmatically (section 3.15 in http://www.gazept.com/dl/Gazepoint_API_v2.0.pdf).

Thanks again,

Titus


#4

Hi Titus,

ioHub has its own process that it runs in, the GP3 has its own app called “Gazepoint Control” that needs to be running in order to communicate with the GP3, and then you have psychopy running, hence why you need a multi-cored processor.

Thanks
Martin


#5

We are considering buying a GP3 and wonder about which was your experience with this eyectracker using Psychopy?