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diff --git a/docs/user_guide/gaze_analysis/gaze_movement.md b/docs/user_guide/gaze_analysis/gaze_movement.md deleted file mode 100644 index 83f67e1..0000000 --- a/docs/user_guide/gaze_analysis/gaze_movement.md +++ /dev/null @@ -1,163 +0,0 @@ -Gaze movement -============= - -## Definition - -!!! note - - *"The act of classifying eye movements into distinct events is, on a general level, driven by a desire to isolate different intervals of the data stream strongly correlated with certain oculomotor or cognitive properties."* - - Citation from ["One algorithm to rule them all? An evaluation and discussion of ten eye movement event-detection algorithms"](https://link.springer.com/article/10.3758/s13428-016-0738-9) article. - -[GazeFeatures](../../argaze.md/#argaze.GazeFeatures) defines abstract [GazeMovement](../../argaze.md/#argaze.GazeFeatures.GazeMovement) class, then abstract [Fixation](../../argaze.md/#argaze.GazeFeatures.Fixation) and [Saccade](../../argaze.md/#argaze.GazeFeatures.Saccade) classes which inherit from [GazeMovement](../../argaze.md/#argaze.GazeFeatures.GazeMovement). - -The **positions** [GazeMovement](../../argaze.md/#argaze.GazeFeatures.GazeMovement) attribute contain all [GazePositions](../../argaze.md/#argaze.GazeFeatures.GazePosition) belonging to itself. - - - -## Identification - -[GazeFeatures](../../argaze.md/#argaze.GazeFeatures) defines abstract [GazeMovementIdentifier](../../argaze.md/#argaze.GazeFeatures.GazeMovementIdentifier) classe to let add various identification algorithms. - -Some gaze movement identification algorithms are available thanks to [GazeAnalysis](../../argaze.md/#argaze.GazeAnalysis) submodule: - -* [Dispersion threshold identification (I-DT)](../../argaze.md/#argaze.GazeAnalysis.DispersionThresholdIdentification) -* [Velocity threshold identification (I-VT)](../../argaze.md/#argaze.GazeAnalysis.VelocityThresholdIdentification) - -### Identify method - -[GazeMovementIdentifier.identify](../../argaze.md/#argaze.GazeFeatures.GazeMovementIdentifier.identify) method allows to fed its identification algorithm with successive gaze positions to output Fixation, Saccade or any kind of GazeMovement instances. - -Here is a sample of code based on [I-DT](../../argaze.md/#argaze.GazeAnalysis.DispersionThresholdIdentification) algorithm to illustrate how to use it: - -``` python -from argaze import GazeFeatures -from argaze.GazeAnalysis import DispersionThresholdIdentification - -# Create a gaze movement identifier based on dispersion algorithm with 50px max deviation 200 ms max duration thresholds -gaze_movement_identifier = DispersionThresholdIdentification.GazeMovementIdentifier(50, 200) - -# Assuming that timestamped gaze positions are provided through live stream or later data reading -...: - - gaze_movement = gaze_movement_identifier.identify(timestamp, gaze_position) - - # Fixation identified - if GazeFeatures.is_fixation(gaze_movement): - - # Access to first gaze position of identified fixation - start_ts, start_position = gaze_movement.positions.first - - # Access to fixation duration - print('duration: {gaze_movement.duration}') - - # Iterate over all gaze positions of identified fixation - for ts, position in gaze_movement.positions.items(): - - # Do something with each fixation position - ... - - # Saccade identified - elif GazeFeatures.is_saccade(gaze_movement): - - # Access to first gaze position of identified saccade - start_ts, start_position = gaze_movement.positions.first - - # Access to saccade amplitude - print('amplitude: {gaze_movement.amplitude}') - - # Iterate over all gaze positions of identified saccade - for ts, position in gaze_movement.positions.items(): - - # Do something with each saccade position - ... - - # No gaze movement identified - else: - - continue - -``` - -### Browse method - -[GazeMovementIdentifier.browse](../../argaze.md/#argaze.GazeFeatures.GazeMovementIdentifier.browse) method allows to pass a [TimeStampedGazePositions](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazePositions) buffer to apply identification algorithm on all gaze positions inside. - -Identified gaze movements are returned through: - -* [TimeStampedGazeMovements](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazeMovements) instance where all fixations are stored by starting gaze position timestamp. -* [TimeStampedGazeMovements](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazeMovements) instance where all saccades are stored by starting gaze position timestamp. -* [TimeStampedGazeStatus](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazeStatus) instance where all gaze positions are linked to a fixation or saccade index. - -``` python -# Assuming that timestamped gaze positions are provided through data reading - -ts_fixations, ts_saccades, ts_status = gaze_movement_identifier.browse(ts_gaze_positions) - -``` - -* ts_fixations would look like: - -|timestamp|positions |duration|dispersion|focus | -|:--------|:-------------------------------------------------------------|:-------|:---------|:--------| -|60034 |{"60034":[846,620], "60044":[837,641], "60054":[835,649], ...}|450 |40 |(840,660)| -|60504 |{"60504":[838,667], "60514":[838,667], "60524":[837,669], ...}|100 |38 |(834,651)| -|... |... |... |.. |... | - -* ts_saccades would look like: - -|timestamp|positions |duration| -|:--------|:---------------------------------------|:-------| -|60484 |{"60484":[836, 669], "60494":[837, 669]}|10 | -|60594 |{"60594":[833, 613], "60614":[927, 601]}|20 | -|... |... |... | - -* ts_status would look like: - -|timestamp|position |type |index| -|:--------|:---------|:-------|:----| -|60034 |(846, 620)|Fixation|1 | -|60044 |(837, 641)|Fixation|1 | -|... |... |... |. | -|60464 |(836, 668)|Fixation|1 | -|60474 |(836, 668)|Fixation|1 | -|60484 |(836, 669)|Saccade |1 | -|60494 |(837, 669)|Saccade |1 | -|60504 |(838, 667)|Fixation|2 | -|60514 |(838, 667)|Fixation|2 | -|... |... |... |. | -|60574 |(825, 629)|Fixation|2 | -|60584 |(829, 615)|Fixation|2 | -|60594 |(833, 613)|Saccade |2 | -|60614 |(927, 601)|Saccade |2 | -|60624 |(933, 599)|Fixation|3 | -|60634 |(934, 603)|Fixation|3 | -|... |... |... |. | - - -!!! note - [TimeStampedGazeMovements](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazeMovements), [TimeStampedGazeMovements](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazeMovements) and [TimeStampedGazeStatus](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazeStatus) classes inherit from [TimeStampedBuffer](../../argaze.md/#argaze.DataStructures.TimeStampedBuffer) class. - - Read [Timestamped data](../timestamped_data/introduction.md) section to understand all features it provides. - -### Generator method - -[GazeMovementIdentifier](../../argaze.md/#argaze.GazeFeatures.GazeMovementIdentifier) can be called with a [TimeStampedGazePositions](../../argaze.md/#argaze.GazeFeatures.TimeStampedGazePositions) buffer in argument to generate gaze movement each time one is identified. - -``` python -# Assuming that timestamped gaze positions are provided through data reading - -for ts, gaze_movement in gaze_movement_identifier(ts_gaze_positions): - - # Fixation identified - if GazeFeatures.is_fixation(gaze_movement): - - # Do something with each fixation - ... - - # Saccade identified - elif GazeFeatures.is_saccade(gaze_movement): - - # Do something with each saccade - ... -```
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