Re: [Openeeg-list] EDF to ASCII and ASCII to EDF

[Nathan W. <nat...@ya...>]

Helen Barkan wrote:

>  http://www.neurotraces.com/
>
>  A site where they claim you can download their converter that does both
>  ASCII--> EDF and EDF--> ASCII via a cute GUI - however am a little wary
>  that last update to that site was in 2004. not a good sign. anybody
>  knows those folks? The site is rahter cool but I am not sure about some
>  entries - for example, "audification of biologic signals" ...  <snip> ...
>  I will try their converter though. 

Hi Helen -

  Some background, and a few ideas re your ascii to EDF conversion need:

  Jesus Olivan, M.D., who put up the neurotraces.com site, is a specialist 
  in epilepsy who collaborated in 2003 with Bob Kemp, Ph.D. to a publish
  "EDFplus" (EDF+), a revision to Kemp, et. al.'s original 1992 specification 
  of EDF.  Wikipedia ( http://en.wikipedia.org/wiki/European_data_format )
  describes this, but doesn't name any names. Kemp's website (see following)
  lists Olivan as still actively involved with EDF in 2006, and Kemp himself 
  remains fully dedicated to the promulgation of the standard.

  The info on the neurotraces.com website about converting bio-signals 
  to sound can probably be made better sense of by reviewing the paper 
  below. It's an interesting idea: review polysomnogram data through 
  audition, at least use the modality to supplement visual review. Kemp heads 
  a large sleep clinic; he probably wanted a faster way to review polysomno-
  grams.   
   
      -  J. Olivan, B. Kemp, M. Roessen      
         Easy listening to sleep recordings: tools and examples. 
         Sleep Medicine, Volume 5, Issue 6, Pages 601-603
         ( www.hsr.nl/bobkemp/papers/2004Easy%20listeningToSleep.pdf )

  Kemp's publication credits are as extensive as I've seen before, and they  
  include your own Epilepsia, btw. He's produced some beautiful research 
  results on sleep, as well.

  Papers on EDF and EDFplus, and One New Competing Format

   -  Kemp B, Värri A, Rosa AC, Nielsen KD, Gade J. 
       A simple format for exchange of digitized polygraphic recordings.
       Electroenceph clin Neurophysiol 1992;82:391–3.
       ( http://www.hsr.nl/bobkemp/papers/1992EDF.pdf )

   -  Kemp B, Olivan J. 
       European data format 'plus' (EDF+), an EDF alike 
       standard format for the exchange of physiological data. 
       Clinical Neurophysiology 114, 2003: 1755-1761.
       ( http://www.hsr.nl/bobkemp/papers/2003EDFplus.pdf )

    -  Kemp B.
        SignalML from an EDF+ perspective
        Computer Methods and Programs in Biomedicine (2004) 76, 261—263
        ( http://www.hsr.nl/bobkemp/papers/2004%20EDFandSignalML.pdf )
        ( SignalML is an upstart competitor to EDF/EDF+ )

  Contact Information:

     Bob Kemp, Ph.D.  
     email:  bk...@hs...
     home page:  www.hsr.nl/bobkemp/index.html
     located in the Netherlands

     Jesus Olivan, M.D. contact info (?)
     email: jol...@wo... (sic)
     email: jo...@ne...
     email: fo...@ne...
     home page:  www.neurotraces.com
     located in Spain

-

  Based on Chris' comment that the converter on the neurotraces.com
  site isn't suitable for multichannel EEG, I presume you're still looking 
  for a solution?

  Possibly this is too obvious to mention, but does the maker of the 
  equipment with which you captured your ESES & CSWS data offer 
  any format conversion utility?  Or can you press another manufacturer's  
  software into service for the purpose?   

  For example, I see from www.edfplus.info/companies/companies.html 
  that Grass's EEG units are represented there.  You probably have Grass's 
  'TWin' software accessible to you somewhere - it's my understanding 
  it comes with every Grass EEG. I know the software can write both 
  EDF and ascii.  But if it can write ascii ... does that mean it would 
  probably be able to read back the ascii it writes, too; i.e., is there  
  an ascii import utility?
 
  Or if not Grass, then Xltek, or even one of the polysomnography equip 
  vendors listed on the page might have some data interchange facility 
  that could do the job.  Or perhaps your Sleep Medicine people would 
  know if their software has an "ascii in, EDF out" utility?

-

   On a related note, none of your sample data came from a Nihon 
   Kohden EEG, I suppose?  I presume you saw the just-released 
   ( 0.43 21 march 2007 ) version of software to convert Nihon 
   Kohden format data to EDF(+) at http://www.teuniz.net/edf/ ?

   ( It looks like there are binaries there only for linux, but if you 
     scroll down the page, you'll see the zip file for WinXP; the 
     source code is there, too. HOW easily adaptable, I wonder? )

    Actually, I don't really understand that... This page 
    http://www.edfplus.info/companies/companies.html
    says Nihon Kohden EEGs read and write EDF... Oh; 
    maybe the teuniz.net software takes EDF to EDFplus?
    Or converts output of older, non-EDF (?) NK equipment 
    to newer EDF/EDFplus? Worth finding out, if applicable, 
    I'd guess.

-

   Of course you also saw the tutorial that Jesus Olivan put together 
   "Applying PhysioNet tools to manage neurophysiological signals"
    that demonstrates how to convert an ascii EKG signal to EDF at 
    http://www.neurotraces.com/InPractice/ECG/ECG.html, right?

-

   The moderated EDF group on Yahoo could be of help:

          http://tech.groups.yahoo.com/group/EDF/  

    Seems to take a couple of days for the moderator to grant 
    access, though.

-

   A final thought, perhaps impracticable ... but w/b very simple:

   Ask to borrow some sample data that comprises ESES (electrographic 
   status epilepticus of sleep) and CSWS (continuous spike wave sleep 
   activity) from one of your European colleagues, e.g. Kemp or Olivan,
   who are into epilepsy research too.  Olivan seemed something like 
   eager to help others, I thought, based on my perusal of his website, 
   and I got a similar feel from reading Kemp's site. The academic 
   equivalent of going next door to borrow a cup of sugar? ( A pleasing, 
   homely image, that. ) Would such a request be considered bad form?  
   Or perhaps ESES and CSWS aren't common enough that another 
   clinic or lab would be likely to have some representative data 
   they could put their hands on easily? Or maybe EU's strict 
   data security requirements would prevent this, even if it were 
   otherwise plausible?  Or, better, maybe they could direct you to 
   an already-complete data format conversion utility somewhere.
   Who would know better than they whether such exists?

-

   I imagine I've made a few "village idiot" suggestions here, and I know
   you probably knew most or all of it, besides.  But thought I'd have a 
   go, anyway.  Good learning for me, and besides, it's always much     
   more fun to make recommendations about how someone else might 
   do their work than to actually do one's own! 
   
   cheers,

   Nathan

   PS - Refs soon for QEEG and scalp gamma band; very much a "learn 
          as I go" project to try to understand the abstracts and papers 
          I'm finding.  Thanks for the interest Helen, Joerg.  Soon.