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EDF File Writer

Posted: Tue Mar 24, 2015 11:04 am
by Psemaj
Using a simple example of the Acquisition client with the Generic Oscillator driver, I have been unable to use the EDF file writer to successfully import the data into EEGLAB. I've checked that the output of the AC is fine, by writing to CSV and plotting it - and it is. However, I can't get the same result in EEGLAB. I've also tried converting the csv into edf using the conversion example with OpenViBE.

The imported EDF has the right parameters, such as sampling frequency, channels, time interval, etc., but when plotting the data it looks like it has been undersampled and highly discretised. A sample of what I mean is below, where the plot on the write is the imported EDF and on the right is an Excel plot of the csv data.

Image

Has anyone else experienced this, or knows how to fix it?

TIA.

Re: EDF File Writer

Posted: Mon May 04, 2015 8:51 am
by jtlindgren
Hi,

in the last few years we haven't really used EDF at Inria (as far as I know), nor do we have
any tests for it. So I don't have counterevidence to claim that it wouldn't be broken --
it might be. The box is a contribution from the community. I'll add it on our todo list to
investigate, but I cannot say when we'll have time to look into it. Meanwhile, if anybody
confirms the problem and submits a fix, I'm happy to merge the patch.


Cheers,
Jussi