Gaze data callback function not triggering in Python

[Nav D]

Hello.

I just got my eye tracker 5 and i am trying to access the gaze data from the device. I have installed tobii_research package and i can detect the device without issues.
However, my gaze_data_callback function does not trigger after subscribing to EYETRACKER_GAZE_DATA

The print logs should fire from within gaze_data_callback(gaze_data) but the output that i get is :

========================================
Found 1 eye tracker(s).
Attempting to subscribe to gaze data of eye tracker: <tobiiresearch.implementation.EyeTracker.EyeTracker object at 0x0000019A58E1AB60>
Successfully subscribed to gaze data.
=======================================
Has anyone had this issue?

Below is my code.

import tobii_research as tr
import time

def gaze_data_callback(gaze_data):
print(“Gaze data received.”)
left_eye_point = gaze_data[‘left_gaze_point_on_display_area’]
right_eye_point = gaze_data[‘right_gaze_point_on_display_area’]
print(f”Left eye gaze point: {left_eye_point}”)
print(f”Right eye gaze point: {right_eye_point}”)

eyetrackers = tr.find_all_eyetrackers()
if not eyetrackers:
print(“No eye trackers found.”)
exit(1)

print(f”Found {len(eyetrackers)} eye tracker(s).”)
my_eyetracker = eyetrackers[0]

try:
print(f”Attempting to subscribe to gaze data of eye tracker: {my_eyetracker}”)
my_eyetracker.subscribe_to(tr.EYETRACKER_GAZE_DATA, gaze_data_callback)
print(“Successfully subscribed to gaze data.”)
except Exception as e:
print(f”Failed to subscribe to gaze data: {e}”)
exit(1)

print(“Press Enter to exit…”)
try:
while True:
time.sleep(1)
except KeyboardInterrupt:
pass

print(“Unsubscribing from gaze data.”)
my_eyetracker.unsubscribe_from(tr.EYETRACKER_GAZE_DATA, gaze_data_callback)
print(“Done.”)

[Grant [Tobii]]

Hi, the tobii_research package SDK is only for Tobii Pro Eye Trackers. The Tobii Eye Tracker 5 only interfaces with the Stream Engine API for which you can make a request for access @ https://developer.tobii.com/software-downloads/

[Nav D]

Thanks for the reply.
So is there any Python wrapper for stream engine api ?
Or C++ is the only option if you want to work with Gaze data from eye tracker 5?

[Nav D]

Also although i have already requested the stream engine api through your provided link, how long do i typically need to wait before i can access it ?

[Grant [Tobii]]

Hi Nav, please send me a PM with the email you used to register interest and I will check it for you.

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