Re: CASA problems and solutions

["John K. Bates" <jkbates@xxxxxxxxxxxx>]

John,
  Thank you for the comments on sound localization and reverberations.
I'll check it out.
  My emphasis on direction of arrival was based on using it to test whether
the interstitial waveform sampling idea has legs.  It seems that it does.
  However, in my system localization is not really the first phase of the
separation process, nor is it necessary for separation.  The suggestion
that separation occurs first is correct.  In my sampling method, the
waveform information vectors represent the first phase of separation
because they contain the information by which source streams may be
identified.
  I'm not sure how that fits in with the previous experiments, but it does
make sense to me.

   Cheers,

    John Bates
    Time/Space Systems
    Pleasantville, New York

At 11:12 AM 01/30/2001 GMT, you wrote:
>John,
>
>While I wouldn't want to prejudge the usefulness of your approach as a
>method for scene analysis by machines (I've heard some impressive
>reverberation-suppression demos of Birger Kollmeier's), it seems
>evident that humans do not use the cues in the way you describe.
>Firstly, although human sound localisation works quite well in
>reverberant environments, humans have great difficulty using
>differences in source location to separate speech in reverberation
>(Plomp, 1976; Culling et al., 1994; Darwin and Hukin, 2000). Second,
>there is some reason to doubt that sound localisation is a pre-cursor
>to sound separation (Culling and Summerfield, 1995; Hukin and Darwin,
>1995). Darwin and Hukin (1999) have suggested that separation occurs
>first, and that the processes of sound localisation are then applied
>to already-separated auditory objects.
>
>John.
>
>Plomp, R (1976). Acustica, 34, 200-211.
>Culling, JF, Summerfield, Q, and Marshall, DH (1994). Speech Comm. 14, 71-95.
>Darwin, CJ and Hukin RW (2000) JASA, 108, 335-342.
>Culling, JF and Summerfield, Q (1995) JASA 98, 785-797.
>Hukin, RW, and Darwin, CJ (1995) JASA 98, 1380-1387.
>Darwin, CJ and Hukin, RW (1999) JEP:HPP 25, 617-629.
>
>