MPS

MPS stands for "Machine Perception Services" and are a service provided by the Aria device recordings.

Trajectory

Please read the Official Aria Documentation

Trajectory data provides the 3D camera positions of the camera wearer, sampled at 1kHZ across the capture & each take.

Here is some basic information about the trajectories:

• You can determine if a capture has an associated trajectory by referring to the field has_trajectory, or has_trimmed_trajectory if there is a take-trimmed counter-part
• The files related to the trajectory is located in the trajectory folder relative to the capture (use the closed_loop_trajectory.csv file) or the take; if there is a take-trimmed counter-part (has_trimmed_trajectory): use trimmed_trajectory_relative_path from the take.
• The intrinsic parameters are provided in the trajectory directory for the exo-centric GoPro cameras (gopro_calibs.csv); for the aria camera it is provided in the capture, or the take-trimmed, VRS file.
• Here is a code sample on how to read the closed loop file.

Point Clouds

Point clouds are located in the trajectory subdirectory for each capture. Please familiarize yourself with the official documentation from Project Aria, as the files referenced in Aria's documentation are present in the trajectory folder.

Below is some basic information about point clouds:

• Every capture that has trajectory will have a point cloud. Use the has_trajectory field to classify which captures have trajectories & point clouds.
  • The files associated to point clouds are: semidense_observations.csv.gz and semidense_points.csv.gz
• Point clouds are associated to multiple (arbitrary) timepoints within the video, please read Aria's documentation
• Point clouds are in the same 3D coordinate system as the trajectory data.
• Here is a code sample on how to read the point cloud data from Project Aria

Eye Gaze

Eye gaze data is located in each captures' or takes' eye_gaze folder. Please familiarize yourself with the official documentation from Project Aria, as the files referenced in Aria's documentation will be present in the eye_gaze folder.

Below is some basic information about eye gaze:

• You can determine if a take or capture has eye gaze by using the field has_gaze for a capture and has_trimmed_gaze for a take.
  • If eye gaze is available for the take, it is trimmed (cropped in time) with respect to that take.
• Here is a code sample on how to read the eye gaze data from Project Aria

To quickly start using MPS in code, see the MPS Quickstart Notebook.