Plots

PreviousStream Generation NextValidation

Last updated 1 month ago

Plots

This section explores the visualization features of the pyETA GUI in a tabbed layout, specifically the Gaze Plots and Fixation Plot. These plots transform the real-time eye-tracking data into intuitive displays, assisting with analyzing eye movements and attention patterns effectively. These plots are updated with a specific rate which can be selected in the sidebar of the GUI.

The "Gaze Data" tab presents two time-based graphs tracking horizontal and vertical eye positions, while the "Fixation" tab offers a spatial scatter plot highlighting where the eyes linger. These plots draw from the live 'tobii_gaze_fixation' stream, providing a window into both the motion and stability of a user's gaze.

Located in the Gaze Data tab, the gaze plots consist of two separate graphs: one for horizontal (X) gaze position and another for vertical (Y) gaze position. Each plot traces eye movement over time, offering a chronological view of where the eyes are looking on the screen.

Interpretation

Horizontal Axis (Time): The X-axis represents time elapsed since the stream began, measured in seconds. It is a moving axis with windows of 10 sec
Vertical Axis (Position):
- The X Position Plot shows the gaze’s horizontal location in pixels, spanning from the left edge (0) to the right edge of the screen (e.g., 1920 on a 1920x1080 display). A steady line suggests the eyes are fixed horizontally, while sharp jumps indicate rapid shifts, such as when scanning side to side.
- The Y Position Plot tracks the vertical position, ranging from the top (0) to the bottom of the screen (e.g., 1080 on a 1920x1080 display). Smooth curves might reflect gradual vertical scanning, like reading, while abrupt changes signal quick upward or downward movements.
Insights: These plots reveal dynamic eye behavior. For instance, a flat line on the X plot paired with small dips on the Y plot could indicate reading text line by line. Frequent jagged peaks suggest erratic or exploratory eye movements, while filtered data smooths out minor jitters to highlight meaningful trends.

Located in the Fixation tab, the fixation plot is a two-dimensional scatter display that maps where the eyes pause on the screen. Each point represents a fixation moment when the gaze remains still, this is plotted against the screen’s width and height.

Interpretation

Horizontal Axis (Pixel): Represents the screen’s width in pixels, from the left edge (0) to the right (e.g., 1920 on a 1920x1080 display).
Vertical Axis (Pixel): Covers the screen’s height, from the top (0) to the bottom (e.g., 1080 on a 1920x1080 display).
Points: Each marker, shaped like a '+', marks a fixation event—where the eye’s velocity drops below a set threshold, indicating a pause. The size of the marker reflects how long the fixation lasts, growing larger with extended duration (up to a maximum size for clarity). A trail of 10 point are visible each time, corresponding to the buffer size of 10.

PreviousStream Generation NextValidation

Last updated 1 month ago

Interpretation

Horizontal Axis (Time): The X-axis represents time elapsed since the stream began, measured in seconds. It is a moving axis with windows of 10 sec
Vertical Axis (Position):
- The X Position Plot shows the gaze’s horizontal location in pixels, spanning from the left edge (0) to the right edge of the screen (e.g., 1920 on a 1920x1080 display). A steady line suggests the eyes are fixed horizontally, while sharp jumps indicate rapid shifts, such as when scanning side to side.
- The Y Position Plot tracks the vertical position, ranging from the top (0) to the bottom of the screen (e.g., 1080 on a 1920x1080 display). Smooth curves might reflect gradual vertical scanning, like reading, while abrupt changes signal quick upward or downward movements.
Insights: These plots reveal dynamic eye behavior. For instance, a flat line on the X plot paired with small dips on the Y plot could indicate reading text line by line. Frequent jagged peaks suggest erratic or exploratory eye movements, while filtered data smooths out minor jitters to highlight meaningful trends.

Interpretation

Horizontal Axis (Pixel): Represents the screen’s width in pixels, from the left edge (0) to the right (e.g., 1920 on a 1920x1080 display).
Vertical Axis (Pixel): Covers the screen’s height, from the top (0) to the bottom (e.g., 1080 on a 1920x1080 display).
Points: Each marker, shaped like a '+', marks a fixation event—where the eye’s velocity drops below a set threshold, indicating a pause. The size of the marker reflects how long the fixation lasts, growing larger with extended duration (up to a maximum size for clarity). A trail of 10 point are visible each time, corresponding to the buffer size of 10.