Gaze vector data (_g.tsv)

The gaze vector data files contain the processed gaze vector data from eye tracking devices included in the capture.

To export the gaze vector data select the data type Eye tracker in the TSV export options. The gaze vector data will be exported in separate files, for example *_g_1.tsv and *_g_2.tsv with gaze vector data for the left and right eye, respectively. The exported file contains a header section (if checked in the export options) followed by the data section.

The device data of the eye tracker device, for example pupil size data, is exported as analog data, see chapter Analog data (_a.tsv).

Header

  • FILE_VERSION
    Version number of export format, currently 2.0.0.

    FILE_VERSION is not included for versions earlier than 2.0.0.

  • GAZE_VECTOR_NAME
    The name of the gaze vector.

  • NO_OF_SAMPLES
    The number of samples in the gaze vector data.

  • FREQUENCY
    The frequency of the gaze vector data.

  • TIME_STAMP
    Date and time when the motion capture file was made. The date and time is followed by a tab character and then the timestamp in seconds from when the computer was started.

  • START_OFFSET
    The offset time for the first gaze vector frame. It is needed since you may not always cut the measurement range at the start of gaze vector frame. Reduce the start time of the gaze vector data with the offset so that it actually starts before the marker data.

  • HW_SYNC
    Indicates if hardware sync was used (value: YES) for the eye tracker data or not (value: NO).

  • FILTER
    Indicates if the gaze vector data was filtered (value: YES) or not (value: NO).

  • Gaze vector data
    Columns with the gaze vector data in the following order: X Pos, Y Pos, Z Pos, X Vec, Y Vec, Z Vec.

Data

The data is exported in tab-separated columns, where each row represents a sample.

The format of the data part depends on the chosen options.

  • When the Write column header option is checked, a line with column labels is added before the start of the data section. The column headings for each rigid body are:

    • X Pos, Y Pos, Z Pos

      The X/Y/Z Pos values represent the origin of the gaze vector in mm.

    • X Vec, Y Vec, Z Vec

      The X/Y/Z Vec values represent the 3-dimensional normalized gaze vector.

  • When the Write column header option is unchecked, the column order of the data is the same is described above.

  • When the Export time data for every frame option is checked, two columns are added to the left containing time data. The first column (SAMPLE) contains the sample number and the second column (TIME) contains the time in seconds relative to the start of the capture.