Software / Documentation / Data Output

Data Output Reference

Complete reference for Logger data output formats, file structures, and CSV column specifications.

Session Structure

The Logger organizes data hierarchically by session and module:

session_YYYYMMDD_HHMMSS/
├── Cameras/
│   └── {camera_id}/
│       ├── {prefix}_{camera_id}.avi
│       ├── {prefix}_{camera_id}_timing.csv
│       └── {prefix}_{camera_id}_metadata.csv
├── Audio/
│   ├── {timestamp}_AUDIO_trial{NNN}_MIC{id}_{name}.wav
│   └── {timestamp}_AUDIOTIMING_trial{NNN}_MIC{id}_{name}.csv
├── EyeTracker-Neon/
│   ├── {prefix}_GAZEDATA_trial{NNN}.csv
│   ├── {prefix}_SCENE_trial{NNN}.mp4
│   ├── {prefix}_EVENT_trial{NNN}.csv
│   ├── {prefix}_IMU_trial{NNN}.csv
│   └── {prefix}_FRAME_trial{NNN}.csv
├── DRT/
│   └── {timestamp}_DRT_trial{NNN}_{device_id}.csv
├── VOG/
│   └── {timestamp}_VOG_trial{NNN}_{device_type}_{port}.csv
├── GPS/
│   └── {timestamp}_GPS_trial{NNN}.csv
└── Notes/
    └── {timestamp}_NOTES_trial{NNN}.csv

File Naming Conventions

Component Format Example
{timestamp} YYYYMMDD_HHMMSS 20251208_143022
{prefix} trial_NNN trial_001
{NNN} Zero-padded trial number 001, 002, 003
{camera_id} type_bus_device usb_0_001, picam_0
{device_id} Module_dev_port DRT_dev_ttyacm0

Cameras Output

Video File

Property Value
Container AVI
Codec MJPEG (Motion JPEG)
Pixel Format YUV420P

Timing CSV

Column Type Description
trial int Trial number (may be empty)
frame_index int 1-based frame number
capture_time_unix float Unix timestamp (6 decimals)
encode_time_mono float Monotonic time (9 decimals)
sensor_timestamp_ns int Hardware timestamp (CSI only)
video_pts int Presentation timestamp

Full Cameras documentation →

Audio Output

WAV File

Property Value
Format PCM (uncompressed)
Bit Depth 16-bit signed integer
Channels Mono
Sample Rate 48,000 Hz (default)

Timing CSV

Column Type Description
Module string Always "Audio"
trial int Trial number
write_time_unix float Unix timestamp (6 decimals)
chunk_index int Sequential chunk number
write_time_monotonic float Monotonic time (9 decimals)
adc_timestamp float Hardware ADC timestamp
frames int Samples in this chunk
total_frames int Cumulative sample count

Full Audio documentation →

Eye Tracker Output

Scene Video

Property Value
Container MP4
Codec H.264
Resolution Configurable (default 1280x720)

GAZEDATA CSV

Column Type Description
Module string Always "EyeTracker-Neon"
trial int Trial number
gaze_timestamp float Device timestamp
norm_pos_x float Normalized X (0-1)
norm_pos_y float Normalized Y (0-1)
confidence float Gaze confidence (0-1)
worn bool Glasses worn status
pupil_left_diam float Left pupil diameter (mm)
pupil_right_diam float Right pupil diameter (mm)
record_time_unix float System timestamp
record_time_mono float Monotonic time

Full Eye Tracker documentation →

Detection Response Task Output

Detection Response Task CSV (7 columns)

Column Type Description
Device ID string Device identifier
Label string Trial label or "NA"
Unix time in UTC int Host timestamp (seconds)
Milliseconds Since Record int Device time (ms)
Trial Number int Sequential trial count
Responses int Button press count
Reaction Time int RT in ms (-1 = miss)

wDRT CSV (9 columns)

Same as DRT plus:

Column Type Description
Battery Percent int Battery level (0-100%)
Device time in UTC int Device RTC timestamp

Full Detection Response Task documentation →

Visual Occlusion Goggles Output

sVOG CSV (7 columns)

Column Type Description
Device ID string Device identifier
Label string Device port/label
Unix time in UTC float Event timestamp (6 decimals)
Milliseconds Since Record int Time since recording start
Trial Number int Sequential trial count
TSOT int Total Shutter Open Time (ms)
TSCT int Total Shutter Close Time (ms)

wVOG CSV (9 columns)

Same as sVOG plus:

Column Type Description
Lens string Lens state
Battery Percent int Battery level (0-100%)

Full Visual Occlusion Goggles documentation →

GPS Output

GPS CSV (21 columns)

Column Type Description
Module string Always "GPS"
trial int Trial number
timestamp_utc string ISO 8601 UTC time
timestamp_unix float Unix timestamp
record_time_mono float Monotonic time
latitude float Decimal degrees (+ = N)
longitude float Decimal degrees (+ = E)
altitude_m float Altitude (meters)
speed_kmh float Speed (km/h)
heading_true float True heading (degrees)
fix_quality int Fix type (0=None, 1=GPS, 2=DGPS)
satellites_used int Satellites in solution
hdop float Horizontal DOP

Full GPS documentation →

Notes Output

Notes CSV (4 columns)

Column Type Description
Note string Always "Note"
trial int Trial number
Content string Annotation text
Timestamp float Unix timestamp (6 decimals)

Full Notes documentation →

Timestamp Formats

Timestamp Types

Type Format Precision Use Case
Unix timestamp Seconds since 1970-01-01 6 decimal places (microseconds) Cross-system reference
Monotonic time Seconds since boot 9 decimal places (nanoseconds) Cross-module sync
ISO 8601 YYYY-MM-DDTHH:MM:SS.sssZ Milliseconds Human-readable
Hardware timestamp Nanoseconds Nanoseconds Device-specific timing

Synchronization Tip

For best cross-module synchronization, use monotonic timestamps (encode_time_mono, write_time_monotonic, record_time_mono). See the Synchronization Guide for details.