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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Dear FieldTrip community. </font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;"><b>Is it possible to read the data and trial events from a single continuous Neuromag fif dataset, which was automatically split into two separate fif files during recording, because it exceeeded the standard 2 GB file size limitation?</b></font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">The second of the two splitted fif files contains relevant information showing that the second file continues at the time in seconds at which the first file ended. However, if the two fif files are read separately into Field Trip format this information seems to be lost. </font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">FieldTrip seems to support reading in CTF datasets, which have been split into more files due to the 2 GB file size limitation, but I don't know whether there is a method for handling this problem with Neuromag fif data. </font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">( </font><a href="http://fieldtrip.fcdonders.nl/getting_started/ctf?s[]=ctf"><font face="Times New Roman" size="+0" style="font-family:Times New Roman;font-size:12pt;">http://fieldtrip.fcdonders.nl/getting_started/ctf?s[]=ctf</font></a><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;"> )</font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">I presume that it is a general problem that Neuromag fif datasets with 306 channel data sampled at 1 kHz 32 bit floats are splitted into more files, since only ca. 16-18 minutes raw data can be recorded before it is automatically splitted into two files. </font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">The large file size is not a problem after applying MaxFilter procedures to remove high frequency cHPI signals..., etc., and thereafter downsampling e.g. to 16 bit integers sampled at 250 Hz. I see from a previous discussion in another forum that it is not possible to merge (or append) the splitted files with the MaxFilter software. </font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">When reading triggers from splitted fif files there is usually one trial, which starts in the end of the first file and ends in the start of the second file, which cannot be correctly recognized, if the files are treated separately. This is however just a minor problem of loosing a single trial. </font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;"><b>I have a few wrong detections, probably because a few trials are both defined by up-going signals and down-going signals. Would </b><i><b>ft_preprocessing</b></i><b> (and the sub-routines that it calls) take this into consideration, if you e.g. specificy </b><i><b>cfg.detectflank = 'up' </b></i><b>?</b></font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">I'm looking forward to hear any comments, suggestions or solutions. </font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Greetings</font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Niels.</font></div>
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<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Niels Trusbak Haumann</font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">M.A. / PhD student</font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Department of Aesthetic Studies / Center of Functionally Integrative Neuroscience</font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Aarhus University / Aarhus University Hospital</font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">Denmark</font></div>
<div align="left" style="text-align:left;"><font face="Arial" size="+1" color="#000000" style="font-family:Arial;font-size:14pt;color:#000000;">E-mail: <a href="mailto:aestnth@hum.au.dk">aestnth@hum.au.dk</a></font></div>
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