File: ssp.py

package info (click to toggle)
python-mne 0.8.6%2Bdfsg-2
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 87,892 kB
  • ctags: 6,639
  • sloc: python: 54,697; makefile: 165; sh: 15
file content (401 lines) | stat: -rw-r--r-- 15,407 bytes parent folder | download
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
# Authors: Alexandre Gramfort <alexandre.gramfort@telecom-paristech.fr>
#          Matti Hamalainen <msh@nmr.mgh.harvard.edu>
#          Martin Luessi <mluessi@nmr.mgh.harvard.edu>
#
# License: BSD (3-clause)

import copy as cp
from warnings import warn
import numpy as np

from .. import Epochs, compute_proj_evoked, compute_proj_epochs
from ..utils import logger, verbose
from .. import pick_types
from ..io import make_eeg_average_ref_proj
from .ecg import find_ecg_events
from .eog import find_eog_events


def _safe_del_key(dict_, key):
    """ Aux function

    Use this function when preparing rejection parameters
    instead of directly deleting keys.
    """
    if key in dict_:
        del dict_[key]


@verbose
def _compute_exg_proj(mode, raw, raw_event, tmin, tmax,
                      n_grad, n_mag, n_eeg, l_freq, h_freq,
                      average, filter_length, n_jobs, ch_name,
                      reject, flat, bads, avg_ref, no_proj, event_id,
                      exg_l_freq, exg_h_freq, tstart, qrs_threshold,
                      filter_method, iir_params=None, verbose=None):
    """Compute SSP/PCA projections for ECG or EOG artifacts

    Note: raw has to be constructed with preload=True (or string)
    Warning: raw will be modified by this function

    Parameters
    ----------
    mode : string ('ECG', or 'EOG')
        What type of events to detect.
    raw : mne.io.Raw
        Raw input file.
    raw_event : mne.io.Raw or None
        Raw file to use for event detection (if None, raw is used).
    tmin : float
        Time before event in seconds.
    tmax : float
        Time after event in seconds.
    n_grad : int
        Number of SSP vectors for gradiometers.
    n_mag : int
        Number of SSP vectors for magnetometers.
    n_eeg : int
        Number of SSP vectors for EEG.
    l_freq : float | None
        Filter low cut-off frequency in Hz.
    h_freq : float | None
        Filter high cut-off frequency in Hz.
    average : bool
        Compute SSP after averaging.
    filter_length : str | int | None
        Number of taps to use for filtering.
    n_jobs : int
        Number of jobs to run in parallel.
    ch_name : string (or None)
        Channel to use for ECG event detection.
    reject : dict
        Epoch rejection configuration (see Epochs).
    flat : dict
        Epoch flat configuration (see Epochs).
    bads : list
        List with (additional) bad channels.
    avg_ref : bool
        Add EEG average reference proj.
    no_proj : bool
        Exclude the SSP projectors currently in the fiff file.
    event_id : int
        ID to use for events.
    exg_l_freq : float
        Low pass frequency applied for filtering EXG channel.
    exg_h_freq : float
        High pass frequency applied for filtering EXG channel.
    tstart : float
        Start artifact detection after tstart seconds.
    qrs_threshold : float | str
        Between 0 and 1. qrs detection threshold. Can also be "auto" to
        automatically choose the threshold that generates a reasonable
        number of heartbeats (40-160 beats / min). Only for ECG.
    filter_method : str
        Method for filtering ('iir' or 'fft').
    iir_params : dict | None
        Dictionary of parameters to use for IIR filtering.
        See mne.filter.construct_iir_filter for details. If iir_params
        is None and method="iir", 4th order Butterworth will be used.
    verbose : bool, str, int, or None
        If not None, override default verbose level (see mne.verbose).

    Returns
    -------
    proj : list
        Computed SSP projectors.
    events : ndarray
        Detected events.
    """
    if not raw.preload:
        raise ValueError('raw needs to be preloaded, '
                         'use preload=True in constructor')

    if no_proj:
        projs = []
    else:
        projs = cp.deepcopy(raw.info['projs'])
        logger.info('Including %d SSP projectors from raw file'
                    % len(projs))

    if avg_ref:
        eeg_proj = make_eeg_average_ref_proj(raw.info)
        projs.append(eeg_proj)

    if raw_event is None:
        raw_event = raw

    if mode == 'ECG':
        logger.info('Running ECG SSP computation')
        events, _, _ = find_ecg_events(raw_event, ch_name=ch_name,
                                       event_id=event_id, l_freq=exg_l_freq,
                                       h_freq=exg_h_freq, tstart=tstart,
                                       qrs_threshold=qrs_threshold,
                                       filter_length=filter_length)
    elif mode == 'EOG':
        logger.info('Running EOG SSP computation')
        events = find_eog_events(raw_event, event_id=event_id,
                                 l_freq=exg_l_freq, h_freq=exg_h_freq,
                                 filter_length=filter_length, ch_name=ch_name,
                                 tstart=tstart)
    else:
        raise ValueError("mode must be 'ECG' or 'EOG'")

    # Check to make sure we actually got at least one useable event
    if events.shape[0] < 1:
        warn('No %s events found, returning None for projs' % mode)
        return None, events

    logger.info('Computing projector')
    my_info = cp.deepcopy(raw.info)
    my_info['bads'] += bads

    # Handler rejection parameters
    if reject is not None:  # make sure they didn't pass None
        if len(pick_types(my_info, meg='grad', eeg=False, eog=False,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(reject, 'grad')
        if len(pick_types(my_info, meg='mag', eeg=False, eog=False,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(reject, 'mag')
        if len(pick_types(my_info, meg=False, eeg=True, eog=False,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(reject, 'eeg')
        if len(pick_types(my_info, meg=False, eeg=False, eog=True,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(reject, 'eog')
    if flat is not None:  # make sure they didn't pass None
        if len(pick_types(my_info, meg='grad', eeg=False, eog=False,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(flat, 'grad')
        if len(pick_types(my_info, meg='mag', eeg=False, eog=False,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(flat, 'mag')
        if len(pick_types(my_info, meg=False, eeg=True, eog=False,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(flat, 'eeg')
        if len(pick_types(my_info, meg=False, eeg=False, eog=True,
                          ref_meg=False, exclude='bads')) == 0:
            _safe_del_key(flat, 'eog')

    # exclude bad channels from projection
    picks = pick_types(my_info, meg=True, eeg=True, eog=True, ref_meg=False,
                       exclude='bads')
    raw.filter(l_freq, h_freq, picks=picks, filter_length=filter_length,
               n_jobs=n_jobs, method=filter_method, iir_params=iir_params)

    epochs = Epochs(raw, events, None, tmin, tmax, baseline=None, preload=True,
                    picks=picks, reject=reject, flat=flat, proj=True)

    epochs.drop_bad_epochs()
    if epochs.events.shape[0] < 1:
        warn('No good epochs found, returning None for projs')
        return None, events

    if average:
        evoked = epochs.average()
        ev_projs = compute_proj_evoked(evoked, n_grad=n_grad, n_mag=n_mag,
                                       n_eeg=n_eeg)
    else:
        ev_projs = compute_proj_epochs(epochs, n_grad=n_grad, n_mag=n_mag,
                                       n_eeg=n_eeg, n_jobs=n_jobs)

    for p in ev_projs:
        p['desc'] = mode + "-" + p['desc']

    projs.extend(ev_projs)

    logger.info('Done.')

    return projs, events


@verbose
def compute_proj_ecg(raw, raw_event=None, tmin=-0.2, tmax=0.4,
                     n_grad=2, n_mag=2, n_eeg=2, l_freq=1.0, h_freq=35.0,
                     average=False, filter_length='10s', n_jobs=1,
                     ch_name=None, reject=dict(grad=2000e-13, mag=3000e-15,
                                               eeg=50e-6, eog=250e-6),
                     flat=None, bads=[], avg_ref=False,
                     no_proj=False, event_id=999, ecg_l_freq=5, ecg_h_freq=35,
                     tstart=0., qrs_threshold='auto', filter_method='fft',
                     iir_params=None, copy=True, verbose=None):
    """Compute SSP/PCA projections for ECG artifacts

    Note: raw has to be constructed with preload=True (or string)
    Warning: raw will be modified by this function

    Parameters
    ----------
    raw : mne.io.Raw
        Raw input file.
    raw_event : mne.io.Raw or None
        Raw file to use for event detection (if None, raw is used).
    tmin : float
        Time before event in seconds.
    tmax : float
        Time after event in seconds.
    n_grad : int
        Number of SSP vectors for gradiometers.
    n_mag : int
        Number of SSP vectors for magnetometers.
    n_eeg : int
        Number of SSP vectors for EEG.
    l_freq : float | None
        Filter low cut-off frequency in Hz.
    h_freq : float | None
        Filter high cut-off frequency in Hz.
    average : bool
        Compute SSP after averaging.
    filter_length : str | int | None
        Number of taps to use for filtering.
    n_jobs : int
        Number of jobs to run in parallel.
    ch_name : string (or None)
        Channel to use for ECG detection (Required if no ECG found).
    reject : dict
        Epoch rejection configuration (see Epochs).
    flat : dict
        Epoch flat configuration (see Epochs).
    bads : list
        List with (additional) bad channels.
    avg_ref : bool
        Add EEG average reference proj.
    no_proj : bool
        Exclude the SSP projectors currently in the fiff file.
    event_id : int
        ID to use for events.
    ecg_l_freq : float
        Low pass frequency applied for filtering ECG channel.
    ecg_h_freq : float
        High pass frequency applied for filtering ECG channel.
    tstart : float
        Start artifact detection after tstart seconds.
    qrs_threshold : float | str
        Between 0 and 1. qrs detection threshold. Can also be "auto" to
        automatically choose the threshold that generates a reasonable
        number of heartbeats (40-160 beats / min).
    filter_method : str
        Method for filtering ('iir' or 'fft').
    iir_params : dict | None
        Dictionary of parameters to use for IIR filtering.
        See mne.filter.construct_iir_filter for details. If iir_params
        is None and method="iir", 4th order Butterworth will be used.
    copy : bool
        If False, filtering raw data is done in place. Defaults to True.
    verbose : bool, str, int, or None
        If not None, override default verbose level (see mne.verbose).

    Returns
    -------
    proj : list
        Computed SSP projectors.
    ecg_events : ndarray
        Detected ECG events.
    """
    if copy is True:
        raw = raw.copy()

    projs, ecg_events = _compute_exg_proj('ECG', raw, raw_event, tmin, tmax,
                                          n_grad, n_mag, n_eeg, l_freq, h_freq,
                                          average, filter_length, n_jobs,
                                          ch_name, reject, flat, bads, avg_ref,
                                          no_proj, event_id, ecg_l_freq,
                                          ecg_h_freq, tstart, qrs_threshold,
                                          filter_method, iir_params)

    return projs, ecg_events


@verbose
def compute_proj_eog(raw, raw_event=None, tmin=-0.2, tmax=0.2,
                     n_grad=2, n_mag=2, n_eeg=2, l_freq=1.0, h_freq=35.0,
                     average=False, filter_length='10s', n_jobs=1,
                     reject=dict(grad=2000e-13, mag=3000e-15, eeg=500e-6,
                                 eog=np.inf), flat=None, bads=[],
                     avg_ref=False, no_proj=False, event_id=998, eog_l_freq=1,
                     eog_h_freq=10, tstart=0., filter_method='fft',
                     iir_params=None, ch_name=None, copy=True, verbose=None):
    """Compute SSP/PCA projections for EOG artifacts

    Note: raw has to be constructed with preload=True (or string)
    Warning: raw will be modified by this function

    Parameters
    ----------
    raw : mne.io.Raw
        Raw input file.
    raw_event : mne.io.Raw or None
        Raw file to use for event detection (if None, raw is used).
    tmin : float
        Time before event in seconds.
    tmax : float
        Time after event in seconds.
    n_grad : int
        Number of SSP vectors for gradiometers.
    n_mag : int
        Number of SSP vectors for magnetometers.
    n_eeg : int
        Number of SSP vectors for EEG.
    l_freq : float | None
        Filter low cut-off frequency in Hz.
    h_freq : float | None
        Filter high cut-off frequency in Hz.
    average : bool
        Compute SSP after averaging.
    preload : string (or True)
        Temporary file used during computaion.
    filter_length : str | int | None
        Number of taps to use for filtering.
    n_jobs : int
        Number of jobs to run in parallel.
    reject : dict
        Epoch rejection configuration (see Epochs).
    flat : dict
        Epoch flat configuration (see Epochs).
    bads : list
        List with (additional) bad channels.
    avg_ref : bool
        Add EEG average reference proj.
    no_proj : bool
        Exclude the SSP projectors currently in the fiff file.
    event_id : int
        ID to use for events.
    eog_l_freq : float
        Low pass frequency applied for filtering E0G channel.
    eog_h_freq : float
        High pass frequency applied for filtering E0G channel.
    tstart : float
        Start artifact detection after tstart seconds.
    filter_method : str
        Method for filtering ('iir' or 'fft').
    iir_params : dict | None
        Dictionary of parameters to use for IIR filtering.
        See mne.filter.construct_iir_filter for details. If iir_params
        is None and method="iir", 4th order Butterworth will be used.
    copy : bool
        If False, filtering raw data is done in place. Defaults to True.
    ch_name: str | None
        If not None, specify EOG channel name.
    verbose : bool, str, int, or None
        If not None, override default verbose level (see mne.verbose).

    Returns
    -------
    proj: list
        Computed SSP projectors.
    eog_events: ndarray
        Detected EOG events.
    """
    if copy is True:
        raw = raw.copy()
    projs, eog_events = _compute_exg_proj('EOG', raw, raw_event, tmin, tmax,
                                          n_grad, n_mag, n_eeg, l_freq, h_freq,
                                          average, filter_length, n_jobs,
                                          ch_name, reject, flat, bads, avg_ref,
                                          no_proj, event_id, eog_l_freq,
                                          eog_h_freq, tstart,
                                          qrs_threshold='auto',
                                          filter_method=filter_method,
                                          iir_params=iir_params)

    return projs, eog_events