[FEATURE] Post-hoc blink detection

[qian-chu]

Feature Description

Neon already outputs blinks events. However, it sometimes fails to detect blinks, and the duration of blinks are often underestimated. Several post-hoc algorithms exist to detect blinks and durations thereof post hoc. It could be nice to incorporate them as a detect_blinks() method of Stream (eye states).

Proposed Solution

detected_blinks : Events = eye_states.detect_blinks(eye, source, method, parameters)

eye could be:

• "left"
• "right"
• "both" (averages channels from left and right, default)

source could be:

• "pupil" (uses pupil diameter left/right [mm] column)
• "eyelid" (uses eyelid aperture left/right [mm] column, default?)

method flag could be:

• "threshold" (absolute threshold)
• "zscore" (how many standard deviations below mean)
• "hershman" (method in https://doi.org/10.3758/s13428-017-1008-1)

The output Events instance follows the same structure as other blinks (https://docs.pupil-labs.com/neon/data-collection/data-format/#blinks-csv).

[qian-chu]

Some new ideas:

• Maybe the pupil/eyelid data can be filtered to blink rate before detection (5-30Hz?)
• Hershman method requires device-derived blinks to start with, cannot detect blinks missed by Neon natively