Subject: Re: Subtracting regularly repeating sounds From: Matt Flax <flatmax@xxxxxxxx> Date: Thu, 20 Sep 2012 11:54:29 -0500 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>This is a multi-part message in MIME format. --------------000103080403000100070803 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit The exemplar work looks like a good approach, as Jort has provided Matlab code, I would imagine that it could be readily tested for your particular case. Another approach to think about, if you have a section of isolated noise in your audio recording, is the pioneering work by Ephraim & Malah. They produced the statistical method of spectral noise estimation and removal ... the trick in your case would be to make sure that you are using an analysis window which is long enough to be able to capture the low frequency components of your noise source. You can find a SPDemo application in the downloads section on their web page : http://sipl.technion.ac.il/ Matt On 09/20/2012 12:19 AM, Jort Gemmeke wrote: > Dear Kyle, > > I dont have experience with MRI scanner sounds in particular, but it > seems like such a structured interfering source should be a good match > for the exemplar-based source separation techniques I have been using > over the past few years. You can find more information on my website, > www.amadana.nl <http://www.amadana.nl> , as well as a demo (matlab) > and some links to related techniques that may be of use. > > Feel free to contact me directly if you think this can be of use, then > we can give it a try. > > Jort Gemmeke > Postdoctoral Researcher > KU Leuven, ESAT-PSI Speech group > www.amadana.nl <http://www.amadana.nl> > > > Date: Wed, 19 Sep 2012 16:59:06 -0400 > From: Kyle Jasmin <kyle.jasmin.11@xxxxxxxx > <mailto:kyle.jasmin.11@xxxxxxxx>> > Subject: Subtracting regularly repeating sounds > > --bcaec501654d005be504ca1447c5 > Content-Type: text/plain; charset=ISO-8859-1 > > Dear all, > > I wonder if anyone has successfully removed the sound of a helium > pump from > auditory recordings made in an MRI scanner. It occurs regularly > (every 1s), > and changes over time (Praat thinks it is a formant with downward > trajectory). Any advice is appreciated on subtracting regularly > repeating > sounds would be appreciated. > > With thanks, > > Kyle Jasmin > Speech Communication Laboratory, UCL Institute of Cognitive > Neuroscience > & Laboratory of Brain and Cognition, National Institute of Mental > Health > --------------000103080403000100070803 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit <html> <head> <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type"> </head> <body text="#000000" bgcolor="#FFFFFF"> <div class="moz-cite-prefix">The exemplar work looks like a good approach, as Jort has provided Matlab code, I would imagine that it could be readily tested for your particular case.<br> <br> Another approach to think about, if you have a section of isolated noise in your audio recording, is the pioneering work by Ephraim & Malah.<br> They produced the statistical method of spectral noise estimation and removal ... the trick in your case would be to make sure that you are using an analysis window which is long enough to be able to capture the low frequency components of your noise source.<br> <br> You can find a SPDemo application in the downloads section on their web page :<br> <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1"> <a href="http://sipl.technion.ac.il/">http://sipl.technion.ac.il/</a><br> <br> Matt<br> <br> On 09/20/2012 12:19 AM, Jort Gemmeke wrote:<br> </div> <blockquote cite="mid:6150_1348119071_505AAA1F_6150_141_1_CAOo2hPQ4NsEbfQbRDmKdihGc1dmK0vVEUVTyCwqCZK5=yZ+JiA@xxxxxxxx" type="cite">Dear Kyle, <div><br> </div> <div>I dont have experience with MRI scanner sounds in particular, but it seems like such a structured interfering source should be a good match for the exemplar-based source separation techniques I have been using over the past few years. You can find more information on my website, <a moz-do-not-send="true" href="http://www.amadana.nl">www.amadana.nl</a> , as well as a demo (matlab) and some links to related techniques that may be of use.</div> <div><br> </div> <div>Feel free to contact me directly if you think this can be of use, then we can give it a try.</div> <div><br> </div> <div>Jort Gemmeke</div> <div>Postdoctoral Researcher</div> <div>KU Leuven, ESAT-PSI Speech group</div> <div><a moz-do-not-send="true" href="http://www.amadana.nl">www.amadana.nl</a></div> <div><br> </div> <div><br> <div class="gmail_quote"> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Date: Wed, 19 Sep 2012 16:59:06 -0400<br> From: Kyle Jasmin <<a moz-do-not-send="true" href="mailto:kyle.jasmin.11@xxxxxxxx">kyle.jasmin.11@xxxxxxxx</a>><br> Subject: Subtracting regularly repeating sounds<br> <br> --bcaec501654d005be504ca1447c5<br> Content-Type: text/plain; charset=ISO-8859-1<br> <br> Dear all,<br> <br> I wonder if anyone has successfully removed the sound of a helium pump from<br> auditory recordings made in an MRI scanner. It occurs regularly (every 1s),<br> and changes over time (Praat thinks it is a formant with downward<br> trajectory). Any advice is appreciated on subtracting regularly repeating<br> sounds would be appreciated.<br> <br> With thanks,<br> <br> Kyle Jasmin<br> Speech Communication Laboratory, UCL Institute of Cognitive Neuroscience<br> & Laboratory of Brain and Cognition, National Institute of Mental Health<br> <br> </blockquote> </div> </div> </blockquote> <br> </body> </html> --------------000103080403000100070803--