Technical Specifications

Supported Devices

iOS only for now, with Android support planned. Earliest supported device is iPhone 12. LiDAR capture is available on Pro models (iPhone 12 Pro and later).

Video

• Filename: {session_id}_{timestamp}.mp4

• Container: MP4

• Video codec: H.264 or H.265

• Resolution: 1080p at 30fps

• Audio: None (separate audio files if captured with consent)

• Metadata: Embedded + sidecar JSON

Sensor Data (Tabular)

• Filename: {session_id}{sensor}{timestamp}.csv

• Columns: timestamp_ns, [sensor-specific columns]

• Encoding: UTF-8

• Delimiter: Comma

• Header: Included

Example IMU CSV:

timestamp_ns,acc_x,acc_y,acc_z,gyro_x,gyro_y,gyro_z
1706054400000000000,0.023,-9.812,0.042,0.001,-0.002,0.001
1706054400010000000,0.025,-9.808,0.039,0.001,-0.001,0.002

Metadata (JSON)

Each session includes metadata:

{
  "session_id": "abc123def456",
  "device": {
    "model": "iPhone 14 Pro",
    "os_version": "iOS 17.2",
    "sensors": ["camera", "imu", "gps", "barometer"]
  },
  "collection": {
    "start_time": "2026-01-15T10:30:00Z",
    "duration_seconds": 120,
    "campaign_id": "egograsp_q1"
  },
  "anonymization": {
    "location": "coarsened_50m"
  }
}

Coordinate Systems

Device Frame: IMU data is reported in the device coordinate frame.

• X: Right (device held in portrait, screen facing user)

• Y: Up

• Z: Out of screen toward user

Camera Frame: Visual data uses camera conventions.

• X: Right in image

• Y: Down in image

• Z: Forward (into scene)

World Frame: Position data (where available) uses WGS84 (latitude, longitude, altitude). All coordinates are coarsened to 50m+ before upload.

Approximate Data Rates

Data Type	Rate
RGB Video (1080p30)	~10 MB/min
IMU (100Hz)	~0.5 MB/min