[Mne_analysis] downsampling in bdf file

[Eric Larson]

I'm not familiar with the edfbrowser routines, but if they use standard
low-pass-downsample methods instead of a zero-order hold for the stimulus
channel, the low-pass filter ringing will produce many errant events. When
you say that you tested the file using MATLAB, you mean that you opened it?
Did you look at the stimulus channel to see if the resampling introduced
ringing?

Cheers,
Eric


On Wed, Jan 14, 2015 at 12:24 PM, Liu Mengting <bigting84 at gmail.com> wrote:

> Hi MNE users,
>
> I am tring to use MNE python to process the bdf EEG file. Since our data
> is huge, so I first downsampled using the edfbrowser which is a bdf
> processing software, then I loaded the downsampled data using
> read_raw_edf(), but I found that the STI channel was totally messed up, I
> can find far more events than there should be.
>
> To make sure the file is good, I tested using matlab and everything works
> well, do you guys have any idea what is going on please?
>
> Thanks and appreciate,
>
> Mengting
>
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