Cropping of Unity Eye Dataset

I just had a small doubt regarding the data generation of Unity.
If we run the UNITY exe file, then we get an image against a 50% grey area but I see that you use properly cropped eye images. Can you please let me know how is this automated
cropping possible?

The issue does not name files or tests; begin by locating the Unity executable and the data-generation path that produces the eye images. Compare the generated image against the cropped eye images, then document how the cropping is automated and where that process occurs.

Written by the indexing model from the issue text.