aboutsummaryrefslogtreecommitdiff
path: root/src/argaze/GazeFeatures.py
blob: 53bec25650126e10dcc1d4c57f9e3584e1a8a997 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
#!/usr/bin/env python

"""Generic gaze data and class definitions."""

__author__ = "Théo de la Hogue"
__credits__ = []
__copyright__ = "Copyright 2023, Ecole Nationale de l'Aviation Civile (ENAC)"
__license__ = "BSD"

""" """

__author__ = "Théo de la Hogue"
__credits__ = []
__copyright__ = "Copyright 2023, Ecole Nationale de l'Aviation Civile (ENAC)"
__license__ = "BSD"

from typing import TypeVar, Tuple, Any
from dataclasses import dataclass, field
import math
import ast
import json

from argaze import DataStructures

import numpy
import pandas
import cv2

@dataclass(frozen=True)
class GazePosition():
    """Define gaze position as a tuple of coordinates with precision."""

    value: tuple[int | float] = field(default=(0, 0))
    """Position's value."""

    precision: float = field(default=0., kw_only=True)
    """Position's precision represents the radius of a circle around \
    this gaze position value where other same gaze position measurements could be."""

    def __getitem__(self, axis: int) -> int | float:
        """Get position value along a particular axis."""

        return self.value[axis]

    def __iter__(self) -> iter:
        """Iterate over each position value axis."""

        return iter(self.value)
    
    def __len__(self) -> int:
        """Number of axis in position value."""

        return len(self.value)

    def __repr__(self):
        """String representation"""

        return json.dumps(self, ensure_ascii = False, default=vars)

    def __array__(self):
        """Cast as numpy array."""

        return numpy.array(self.value)

    @property
    def valid(self) -> bool:
        """Is the precision not None?"""

        return self.precision is not None

    def distance(self, gaze_position) -> float:
        """Distance to another gaze positions."""

        distance = (self.value[0] - gaze_position.value[0])**2 + (self.value[1] - gaze_position.value[1])**2
        distance = numpy.sqrt(distance)

        return distance

    def overlap(self, gaze_position, both=False) -> float:
        """Does this gaze position overlap another gaze position considering its precision?
        Set both to True to test if the other gaze position overlaps this one too."""

        distance = (self.value[0] - gaze_position.value[0])**2 + (self.value[1] - gaze_position.value[1])**2
        distance = numpy.sqrt(distance)

        if both:
            return distance < min(self.precision, gaze_position.precision)
        else:
            return distance < self.precision

    def draw(self, frame: numpy.array, color=(0, 255, 255), draw_precision=True):
        """Draw gaze position point and precision circle."""

        if self.valid:

            int_value = (int(self.value[0]), int(self.value[1]))

            # Draw point at position
            cv2.circle(frame, int_value, 2, color, -1)

            # Draw precision circle
            if self.precision > 0 and draw_precision:
                cv2.circle(frame, int_value, round(self.precision), color, 1)

class UnvalidGazePosition(GazePosition):
    """Unvalid gaze position."""

    def __init__(self, message=None):

        self.message = message

        super().__init__((None, None), precision=None)

TimeStampedGazePositionsType = TypeVar('TimeStampedGazePositions', bound="TimeStampedGazePositions")
# Type definition for type annotation convenience

class TimeStampedGazePositions(DataStructures.TimeStampedBuffer):
    """Define timestamped buffer to store gaze positions."""

    def __setitem__(self, key, value: GazePosition|dict):
        """Force GazePosition storage."""

        # Convert dict into GazePosition
        if type(value) == dict:

            assert(set(['value', 'precision']).issubset(value.keys()))

            if 'message' in value.keys():

                value = UnvalidGazePosition(value['message'])

            else:

                value = GazePosition(value['value'], precision=value['precision'])

        assert(type(value) == GazePosition or type(value) == UnvalidGazePosition)

        super().__setitem__(key, value)

    @classmethod
    def from_json(self, json_filepath: str) -> TimeStampedGazePositionsType:
        """Create a TimeStampedGazePositionsType from .json file."""

        with open(json_filepath, encoding='utf-8') as ts_buffer_file:

            json_buffer = json.load(ts_buffer_file)

            return TimeStampedGazePositions({ast.literal_eval(ts_str): json_buffer[ts_str] for ts_str in json_buffer})

    @classmethod
    def from_dataframe(self, dataframe: pandas.DataFrame, exclude=[]) -> TimeStampedGazePositionsType:
        """Create a TimeStampedGazePositions from [Pandas DataFrame](https://pandas.pydata.org/docs/reference/api/pandas.DataFrame.html)."""

        dataframe.drop(exclude, inplace=True, axis=True)

        assert(dataframe.index.name == 'timestamp')

        return TimeStampedGazePositions(dataframe.to_dict('index'))

GazeMovementType = TypeVar('GazeMovement', bound="GazeMovement")
# Type definition for type annotation convenience

@dataclass(frozen=True)
class GazeMovement():
    """Define abstract gaze movement class as a buffer of timestamped positions."""

    positions: TimeStampedGazePositions
    """All timestamp gaze positions."""

    duration: float = field(init=False)
    """Inferred duration from first and last timestamps."""

    amplitude: float = field(init=False)
    """Inferred amplitude from first and last positions."""

    def __post_init__(self):

        start_position_ts, start_position = self.positions.first
        end_position_ts, end_position = self.positions.last

        # Update frozen duration attribute
        object.__setattr__(self, 'duration', end_position_ts - start_position_ts)

        _, start_position = self.positions.first
        _, end_position = self.positions.last

        amplitude = numpy.linalg.norm( numpy.array(start_position.value) - numpy.array(end_position.value))

        # Update frozen amplitude attribute
        object.__setattr__(self, 'amplitude', amplitude)

    def __str__(self) -> str:
        """String display"""

        output = f'{type(self)}:\n\tduration={self.duration}\n\tsize={len(self.positions)}'

        for ts, position in self.positions.items():

            output += f'\n\t{ts}:\n\t\tvalue={position.value},\n\t\taccurracy={position.precision}'

        return output

    def draw_positions(self, frame: numpy.array, color=(0, 55, 55)):
        """Draw gaze movement positions"""

        gaze_positions = self.positions.copy()

        while len(gaze_positions) >= 2:

            ts_start, start_gaze_position = gaze_positions.pop_first()
            ts_next, next_gaze_position = gaze_positions.first

            # Draw start gaze
            start_gaze_position.draw(frame, draw_precision=False)

            # Draw movement from start to next
            cv2.line(frame, start_gaze_position, next_gaze_position, color, 1)

FixationType = TypeVar('Fixation', bound="Fixation")
# Type definition for type annotation convenience

class Fixation(GazeMovement):
    """Define abstract fixation as gaze movement."""

    focus: tuple = field(init=False)
    """Representative position of the fixation."""

    def __post_init__(self):

        super().__post_init__()

    def merge(self, fixation) -> FixationType:
        """Merge another fixation into this fixation."""

        raise NotImplementedError('merge() method not implemented')

    def draw(self, frame: numpy.array, color):
        """Draw fixation into frame."""

        raise NotImplementedError('draw() method not implemented')

def is_fixation(gaze_movement):
    """Is a gaze movement a fixation?"""

    return type(gaze_movement).__bases__[0] == Fixation or type(gaze_movement) == Fixation

class Saccade(GazeMovement):
    """Define abstract saccade as gaze movement."""

    def __post_init__(self):

        super().__post_init__()

    def draw(self, frame: numpy.array, color):
        """Draw saccade into frame."""

        raise NotImplementedError('draw() method not implemented')

def is_saccade(gaze_movement):
    """Is a gaze movement a saccade?"""

    return type(gaze_movement).__bases__[0] == Saccade or type(gaze_movement) == Saccade

TimeStampedGazeMovementsType = TypeVar('TimeStampedGazeMovements', bound="TimeStampedGazeMovements")
# Type definition for type annotation convenience

class TimeStampedGazeMovements(DataStructures.TimeStampedBuffer):
    """Define timestamped buffer to store gaze movements."""

    def __setitem__(self, key, value: GazeMovement):
        """Force value to be or inherit from GazeMovement."""

        assert(isinstance(value, GazeMovement) or type(value).__bases__[0] == Fixation or type(value).__bases__[0] == Saccade)

        super().__setitem__(key, value)

    def __str__(self):

        output = ''
        for ts, item in self.items():

            output += f'\n{item}'

        return output

GazeStatusType = TypeVar('GazeStatus', bound="GazeStatus")
# Type definition for type annotation convenience

@dataclass(frozen=True)
class GazeStatus(GazePosition):
    """Define gaze status as a gaze position belonging to an identified and indexed gaze movement."""

    movement_type: str = field(kw_only=True)
    """GazeMovement type to which gaze position belongs."""

    movement_index: int = field(kw_only=True)
    """GazeMovement index to which gaze positon belongs."""

    @classmethod
    def from_position(cls, gaze_position: GazePosition, movement_type: str, movement_index: int) -> GazeStatusType:
        """Initialize from a gaze position instance."""

        return cls(gaze_position.value, precision=gaze_position.precision, movement_type=movement_type, movement_index=movement_index)

TimeStampedGazeStatusType = TypeVar('TimeStampedGazeStatus', bound="TimeStampedGazeStatus")
# Type definition for type annotation convenience

class TimeStampedGazeStatus(DataStructures.TimeStampedBuffer):
    """Define timestamped buffer to store gaze status."""

    def __setitem__(self, key, value: GazeStatus):
        super().__setitem__(key, value)

class GazeMovementIdentifier():
    """Abstract class to define what should provide a gaze movement identifier."""

    def identify(self, ts, gaze_position, terminate=False) -> GazeMovementType:
        """Identify gaze movement from successive timestamped gaze positions.

            The optional *terminate* argument allows to notify identification algorithm that given gaze position will be the last one.
        """

        raise NotImplementedError('identify() method not implemented')

    def browse(self, ts_gaze_positions: TimeStampedGazePositions) -> Tuple[TimeStampedGazeMovementsType, TimeStampedGazeMovementsType, TimeStampedGazeStatusType]:
        """Identify fixations and saccades browsing timestamped gaze positions."""

        assert(type(ts_gaze_positions) == TimeStampedGazePositions)

        ts_fixations = TimeStampedGazeMovements()
        ts_saccades = TimeStampedGazeMovements()
        ts_status = TimeStampedGazeStatus()

        # Get last ts to terminate identification on last gaze position
        last_ts, _ = ts_gaze_positions.last

        # Iterate on gaze positions
        for ts, gaze_position in ts_gaze_positions.items():

            gaze_movement = self.identify(ts, gaze_position, terminate=(ts == last_ts))

            if is_fixation(gaze_movement):

                start_ts, start_position = gaze_movement.positions.first

                ts_fixations[start_ts] = gaze_movement

                for ts, position in gaze_movement.positions.items():

                    ts_status[ts] = GazeStatus.from_position(position, 'Fixation', len(ts_fixations))

            elif is_saccade(gaze_movement):

                start_ts, start_position = gaze_movement.positions.first

                ts_saccades[start_ts] = gaze_movement

                for ts, position in gaze_movement.positions.items():

                    ts_status[ts] = GazeStatus.from_position(position, 'Saccade', len(ts_saccades))

            else:

                continue

        return ts_fixations, ts_saccades, ts_status

ScanStepType = TypeVar('ScanStep', bound="ScanStep")
# Type definition for type annotation convenience

class ScanStepError(Exception):
    """Exception raised at ScanStepError creation if a aoi scan step doesn't start by a fixation or doesn't end by a saccade."""

    def __init__(self, message):  

        super().__init__(message)

@dataclass(frozen=True)
class ScanStep():
    """Define a scan step as a fixation and a consecutive saccade.
    .. warning::
       Scan step have to start by a fixation and then end by a saccade."""

    first_fixation: Fixation
    """A fixation that comes before the next saccade."""

    last_saccade: Saccade
    """A saccade that comes after the previous fixation."""

    def __post_init__(self):

        # First movement have to be a fixation
        if not is_fixation(self.first_fixation):

            raise ScanStepError('First step movement is not a fixation')

        # Last movement have to be a saccade
        if not is_saccade(self.last_saccade):
            
            raise ScanStepError('Last step movement is not a saccade')

    @property
    def duration(self):
        """Time spent on AOI."""

        # Timestamp of first position of first fixation
        first_ts, _ = self.first_fixation.positions.first 

        # Timestamp of first position of last saccade
        last_ts, _ = self.last_saccade.positions.first 

        return last_ts - first_ts

ScanPathType = TypeVar('ScanPathType', bound="ScanPathType")
# Type definition for type annotation convenience

class ScanPath(list):
    """List of scan steps."""

    def __init__(self):

        super().__init__()
        
        self.__last_fixation = None

    def append_saccade(self, ts, saccade) -> ScanStepType:
        """Append new saccade to scan path and return last new scan step if one have been created."""

        # Ignore saccade if no fixation came before
        if self.__last_fixation != None:

            try: 

                # Edit new step
                new_step = ScanStep(self.__last_fixation, saccade)

                # Append new step
                super().append(new_step)

                # Return new step
                return new_step

            finally:

                # Clear last fixation
                self.__last_fixation = None

    def append_fixation(self, ts, fixation):
        """Append new fixation to scan path.
        !!! warning
                Consecutives fixations are ignored keeping the last fixation"""

        self.__last_fixation = fixation

    def draw(self, frame: numpy.array, fixation_color=(255, 255, 255), saccade_color=(255, 255, 255), deepness=0):
        """Draw scan path into frame."""

        last_step = None
        for step in self[-deepness:]:

            if last_step != None:

                cv2.line(frame, (int(last_step.first_fixation.focus[0]), int(last_step.first_fixation.focus[1])), (int(step.first_fixation.focus[0]), int(step.first_fixation.focus[1])), saccade_color, 2)

                last_step.first_fixation.draw(frame, fixation_color)

            last_step = step

class ScanPathAnalyzer():
    """Abstract class to define what should provide a scan path analyzer."""

    def analyze(self, scan_path: ScanPathType) -> Any:
        """Analyze scan path."""

        raise NotImplementedError('analyze() method not implemented')

AOIScanStepType = TypeVar('AOIScanStep', bound="AOIScanStep")
# Type definition for type annotation convenience

class AOIScanStepError(Exception):
    """Exception raised at AOIScanStepError creation if a aoi scan step doesn't start by a fixation or doesn't end by a saccade."""

    def __init__(self, message, aoi=''):  

        super().__init__(message)

        self.aoi = aoi

@dataclass(frozen=True)
class AOIScanStep():
    """Define a aoi scan step as a set of successive gaze movements onto a same AOI.
    .. warning::
       Aoi scan step have to start by a fixation and then end by a saccade."""

    movements: TimeStampedGazeMovements
    """All movements over an AOI and the last saccade that comes out."""

    aoi: str = field(default='')
    """AOI name."""

    letter: str = field(default='')
    """AOI unique letter to ease sequence analysis."""

    def __post_init__(self):

        # First movement have to be a fixation
        if not is_fixation(self.first_fixation):

            raise AOIScanStepError('First step movement is not a fixation', self.aoi)

        # Last movement have to be a saccade
        if not is_saccade(self.last_saccade):
            
            raise AOIScanStepError('Last step movement is not a saccade', self.aoi)

    @property
    def first_fixation(self):
        """First fixation on AOI."""

        _, first_movement = self.movements.first
        return first_movement

    @property
    def last_saccade(self):
        """Last saccade that comes out AOI."""

        _, last_movement = self.movements.last
        return last_movement

    @property
    def duration(self):
        """Time spent on AOI."""

        # Timestamp of first position of first fixation
        first_ts, _ = self.first_fixation.positions.first 

        # Timestamp of first position of last saccade
        last_ts, _ = self.last_saccade.positions.first 

        return last_ts - first_ts

AOIScanPathType = TypeVar('AOIScanPathType', bound="AOIScanPathType")
# Type definition for type annotation convenience

class AOIScanPath(list):
    """List of aoi scan steps over successive aoi."""

    def __init__(self, expected_aois: list[str] = []):

        super().__init__()
        
        self.__expected_aois = expected_aois
        self.__movements = TimeStampedGazeMovements()
        self.__current_aoi = ''
        self.__index = ord('A')
        self.__aoi_letter = {}
        self.__letter_aoi = {}

        size = len(self.__expected_aois)
        self.__transition_matrix = pandas.DataFrame(numpy.zeros((size, size)), index=self.__expected_aois, columns=self.__expected_aois)

    def __repr__(self):
        """String representation."""

        return str(super())

    def __get_aoi_letter(self, aoi):

        try :

            return self.__aoi_letter[aoi]

        except KeyError:

            letter = chr(self.__index)
            self.__aoi_letter[aoi] = letter
            self.__index += 1
            return letter

    def get_letter_aoi(self, letter):
        """Get which aoi is related to an unique letter."""

        return self.__letter_aoi[letter]

    def __str__(self) -> str:
        """Convert aoi scan path into a string with unique letter per aoi step."""

        sequence = ''
        for step in self:
            sequence += step.letter

        return sequence

    @property
    def expected_aois(self):
        """List of all expected aoi."""

        return self.__expected_aois
    
    @property
    def current_aoi(self):
        """AOI name of aoi scan step under construction"""

        return self.__current_aoi

    @property
    def transition_matrix(self) -> pandas.DataFrame:
        """[Pandas DataFrame](https://pandas.pydata.org/docs/reference/api/pandas.DataFrame.html) where indexes are transition departures and columns are transition destinations."""

        return self.__transition_matrix

    def append_saccade(self, ts, saccade):
        """Append new saccade to aoi scan path."""

        # Ignore saccade if no fixation have been stored before
        if len(self.__movements) > 0:

            self.__movements[ts] = saccade

    def append_fixation(self, ts, fixation, looked_aoi: str) -> bool:
        """Append new fixation to aoi scan path and return last new aoi scan step if one have been created.

        !!! warning
                It could raise AOIScanStepError"""

        if looked_aoi not in self.__expected_aois:

            raise AOIScanStepError('AOI not expected', looked_aoi)

        # Is it fixation onto a new aoi?
        if looked_aoi != self.__current_aoi and len(self.__movements) > 0:

            try: 

                # Edit unique letter per aoi
                letter = self.__get_aoi_letter(self.__current_aoi)

                # Remember which letter identify which aoi
                self.__letter_aoi[letter] = self.__current_aoi

                # Edit new step
                new_step = AOIScanStep(self.__movements, self.__current_aoi, letter)

                # Edit transition matrix
                if len(self) > 0:

                    # Increment [index: source, columns: destination] value
                    self.__transition_matrix.loc[self[-1].aoi, self.__current_aoi,] += 1

                # Append new step
                super().append(new_step)

                # Return new step
                return new_step

            finally:

                # Clear movements
                self.__movements = TimeStampedGazeMovements()

                # Append new fixation
                self.__movements[ts] = fixation

                # Remember new aoi
                self.__current_aoi = looked_aoi
        else:

            # Append new fixation
            self.__movements[ts] = fixation

            # Remember aoi
            self.__current_aoi = looked_aoi

            return None

    def fixations_count(self):
        """Get how many fixations are there in the scan path and how many fixation are there in each aoi."""

        scan_fixations_count = 0
        aoi_fixations_count = {aoi: 0 for aoi in self.__expected_aois}

        for aoi_scan_step in self:

            step_fixations_count = len(aoi_scan_step.movements) - 1 # -1: to ignore last saccade

            scan_fixations_count += step_fixations_count
            aoi_fixations_count[aoi_scan_step.aoi] += step_fixations_count
            
        return scan_fixations_count, aoi_fixations_count

class AOIScanPathAnalyzer():
    """Abstract class to define what should provide a aoi scan path analyzer."""

    def analyze(self, aoi_scan_path: AOIScanPathType) -> Any:
        """Analyze aoi scan path."""

        raise NotImplementedError('analyze() method not implemented')