[Eeglablist] peaks detection

[Elisa Carlino]

Dear all,
i have the following problem on my EEG data.
I have a noisy wave generated by an external trigger
and I need to transform this wave into squared waves
in order to use these waves as events for the
erp analysis.

I attach a jpg of my wave (first line in blu) and a set
of waves that i desire (red waves): i need
- squared waves or
- the first peak of each wave (desirable option) or
- the middle peak of each wave or
- the final peak of each wave.
With the peak I can subsequently epoch
the EEG and analyze the ERPs.

I looked at this function:
[pks,locs] =
findpeaks(canaleTrigger,'MinPeakHeight',2000000,'MinPeakDistance',100,'THRESHOLD',2000000);

I tried to change the values but unsuccessfully.
When I apply this function the program finds too many peaks
and not the first peak of each wave.
Is this function correct? How can I successfully apply the function?
Are there other ways to solve this problem?

Thanks,

Elisa
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