Description of the problem

Bug in interpolate_blinks:

The interpolate_blinks function asks for inputs to "match":
"description of annotations to interpolate over. If a list, the data within all annotations that match any of the strings in the list will be interpolated over."

However the helper function _interpolate_blinks hardcodes the description to "BAD_blink" and doesn't use the inputs entered in "match". Therefore any interpolated blinks, no matter which description is entered in match use the start and end times of any "BAD_blink" annotations.

line 91:
starts, ends = _annotations_starts_stops(raw, "BAD_blink")

Solution:

I rewrote the function to avoid this issue by removing the line defining the starts and ends with the _annotations_starts_stops function and instead just used the “blink_annots” created in the function to define starts and stops of the annotations to interpolate over:

        # Create an empty boolean mask
        mask = np.zeros_like(raw.times, dtype=bool)

        # for annot, start, end in zip(blink_annots, starts, ends):
        for annot in blink_annots:
            if "ch_names" not in annot or not annot["ch_names"]:
                msg = f"Blink annotation missing values for 'ch_names' key: {annot}"
                raise ValueError(msg)
            if ch_info["ch_name"] not in annot["ch_names"]:
                continue  # skip if the channel is not in the blink annotation
            # Update the mask for times within the current blink period
            start = annot["onset"] - pre_buffer
            end = annot["onset"] + annot["duration"] + post_buffer
            
            mask |= (raw.times >= start) & (raw.times <= end)

I also added other interpolation methods to choose from and made the function ignore NaNs in the data. I’ve attached the function below in case this should be useful.

interpolate_blinks_function_custom.rtf

Steps to reproduce

raw = interpolate_blinks(raw, buffer=[0.05, 0.05], match=["BAD_velo_blink", "BAD_merged_blink"], interpolate_gaze=False)

-> would only interpolate over time periods where BAD_blink is annotated. This is especially confusing when blinks are automatically annotated from the eyetracker used (e.g. EyeLink)

Link to data

No response

Expected results

Actual results

Additional information

MNE version: 1.9.0

Operating system (on remote server connected to via ssh): Ubuntu 20.04.6