Repairing ECG artifacts with SSP

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1

Dear all,
When I use the compute_proj_ecg() function to request the projector to fix the artifact, it appears that no projector is activated.The code and console output are shown below.
Best wishes,
ChuNa

from mne.preprocessing import compute_proj_ecg

directory = "G:/OMEGA_RestingState_sample/sub-PD0016/ses-01/meg/sub-PD0016_ses-01_task-rest_run-01_meg.ds"
raw = mne.io.read_raw_ctf(directory, system_clock='truncate', preload=True, clean_names=False, verbose=None)
print(raw.info['projs'])
 
# repairing ECG artifacts with SSP
projs, events = compute_proj_ecg(raw, raw_event=None, tmin=-0.2, tmax=0.4, n_grad=1, n_mag=1, n_eeg=1, l_freq=0.5, h_freq=100.0, ecg_l_freq=0, ecg_h_freq=75, reject=None)
print(raw.info['projs'])
ecg_projs = projs[2:]
print(ecg_projs)

---------------------
Designing a two-pass forward and reverse, zero-phase, non-causal lowpass filter:
- Windowed frequency-domain design (firwin2) method
- Hann window
- Upper passband edge: 75.00 Hz
- Upper transition bandwidth: 0.50 Hz (-12 dB cutoff frequency: 75.25 Hz)
- Filter length: 24000 samples (10.000 sec)

Number of ECG events detected : 592 (average pulse 118 / min.)
Computing projector
Filtering raw data in 1 contiguous segment
Setting up band-pass filter from 0.5 - 1e+02 Hz

FIR filter parameters
---------------------
Designing a two-pass forward and reverse, zero-phase, non-causal bandpass filter:
- Windowed frequency-domain design (firwin2) method
- Hamming window
- Lower passband edge: 0.50
- Lower transition bandwidth: 0.50 Hz (-12 dB cutoff frequency: 0.25 Hz)
- Upper passband edge: 100.00 Hz
- Upper transition bandwidth: 0.50 Hz (-12 dB cutoff frequency: 100.25 Hz)
- Filter length: 24000 samples (10.000 sec)

Not setting metadata
592 matching events found
No baseline correction applied
0 projection items activated
Using data from preloaded Raw for 592 events and 1441 original time points ...
0 bad epochs dropped
No gradiometers found. Forcing n_grad to 0
Adding projection: axial--0.200-0.400-PCA-01
Adding projection: eeg--0.200-0.400-PCA-01
Done.
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2

Hello, you need to add the projection to your data via raw.add_proj()

Best wishes,
Richard

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