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noise removal from audio signal using cepstral analysis

Started by enricophpdsp January 21, 2011
hello,
i have an audio signal mixed with white noise. How do i use the cepstrum
technique to remove the noise from it.

please tell me from where should i start. i want to know the basics of
cepstrum and how can i use it to fullfill my purpose.

please guide me about the literature which i should read.

thanks
On Jan 21, 2:48=A0am, "enricophpdsp"
<enricophpdsp@n_o_s_p_a_m.yahoo.com> wrote:
> hello, > i have an audio signal mixed with white noise. How do i use the cepstrum > technique to remove the noise from it. > > please tell me from where should i start. i want to know the basics of > cepstrum and how can i use it to fullfill my purpose. > > please guide me about the literature which i should read. > > thanks
Why do you want to apply cepstral methods to this problem? What sorts of signals does the cepstrum decompose? Dirk
enricophpdsp schrieb:
> hello, > i have an audio signal mixed with white noise. How do i use the cepstrum > technique to remove the noise from it. > > please tell me from where should i start. i want to know the basics of > cepstrum and how can i use it to fullfill my purpose. > > please guide me about the literature which i should read. > > thanks
The cepstrum is used for analysis and classification of speech but it does not help you to remove noise. If your signal exhibits a low SNR you need to do noise removal before computing a cepstrum. As far as I can remember the Cepstrum expects a 'normalized' input anyways. Google for Spectral Subtraction or Wiener Filters. Greetz, Sebastian
On Jan 22, 5:37=A0am, Sebastian Doht <seb_d...@lycos.com> wrote:
> enricophpdsp schrieb: > > > hello, > > i have an audio signal mixed with white noise. How do i use the cepstru=
m
> > technique to remove the noise from it. > > > please tell me from where should i start. i want to know the basics of > > cepstrum and how can i use it to fullfill my purpose. > > > please guide me about the literature which i should read. > > > thanks > > The cepstrum is used for analysis and classification of speech but it > does not help you to remove noise. If your signal exhibits a low SNR you > need to do noise removal before computing a cepstrum. As far as I can > remember the Cepstrum expects a 'normalized' input anyways. Google for > Spectral Subtraction or Wiener Filters. > > Greetz, > > Sebastian
It can actually. http://ieeexplore.ieee.org/Xplore/login.jsp?url=3Dhttp%3A%2F%2Fieeexplore.i= eee.org%2Fiel5%2F5465897%2F5472440%2F05472686.pdf%3Farnumber%3D5472686&auth= Decision=3D-203 Hardy
HardySpicer schrieb:
> On Jan 22, 5:37 am, Sebastian Doht<seb_d...@lycos.com> wrote: >> enricophpdsp schrieb: >> >>> hello, >>> i have an audio signal mixed with white noise. How do i use the cepstrum >>> technique to remove the noise from it. >> >>> please tell me from where should i start. i want to know the basics of >>> cepstrum and how can i use it to fullfill my purpose. >> >>> please guide me about the literature which i should read. >> >>> thanks >> >> The cepstrum is used for analysis and classification of speech but it >> does not help you to remove noise. If your signal exhibits a low SNR you >> need to do noise removal before computing a cepstrum. As far as I can >> remember the Cepstrum expects a 'normalized' input anyways. Google for >> Spectral Subtraction or Wiener Filters. >> >> Greetz, >> >> Sebastian > > It can actually. > > http://ieeexplore.ieee.org/Xplore/login.jsp?url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel5%2F5465897%2F5472440%2F05472686.pdf%3Farnumber%3D5472686&authDecision=-203 > > Hardy
Thanks for the link. Well, I do not have access to this paper and so I am just trying to deduct from the abstract, that they probably found a way to do operations in the cepstral domain which are usally applied in the correlation domain. Sounds to me like making things more complicated than required but if it saves you some dB it may be worth the effort.
>hello, >i have an audio signal mixed with white noise. How do i use the cepstrum >technique to remove the noise from it. > >please tell me from where should i start. i want to know the basics of >cepstrum and how can i use it to fullfill my purpose. > >please guide me about the literature which i should read. > >thanks >
hello, actually i m participating in an even related to digital signal processing. in that even , the problem statement is not declared, but they have indicated that the participants have to use cepstrum analysis . so please someone tell me that what literature should i read and how should i proceed. thanks for the valuable replies.
On Jan 23, 12:54=A0am, Sebastian Doht <seb_d...@lycos.com> wrote:
> HardySpicer schrieb: > > > > > On Jan 22, 5:37 am, Sebastian Doht<seb_d...@lycos.com> =A0wrote: > >> enricophpdsp schrieb: > > >>> hello, > >>> i have an audio signal mixed with white noise. How do i use the cepst=
rum
> >>> technique to remove the noise from it. > > >>> please tell me from where should i start. i want to know the basics o=
f
> >>> cepstrum and how can i use it to fullfill my purpose. > > >>> please guide me about the literature which i should read. > > >>> thanks > > >> The cepstrum is used for analysis and classification of speech but it > >> does not help you to remove noise. If your signal exhibits a low SNR y=
ou
> >> need to do noise removal before computing a cepstrum. As far as I can > >> remember the Cepstrum expects a 'normalized' input anyways. Google for > >> Spectral Subtraction or Wiener Filters. > > >> Greetz, > > >> Sebastian > > > It can actually. > > >http://ieeexplore.ieee.org/Xplore/login.jsp?url=3Dhttp%3A%2F%2Fieeexplo.=
..
> > > Hardy > > Thanks for the link. Well, I do not have access to this paper and so I > am just trying to deduct from the abstract, that they probably found a > way to do operations in the cepstral domain which are usally applied in > the correlation domain. Sounds to me like making things more complicated > than required but if it saves you some dB it may be worth the effort.
There is a whole literature on noise reduction in the cepstral domain. Much of it revolves around AR modelling, but not all of it. Hardy