jehics@ultb.isc.rit.edu (J.E. Heliotis) (12/15/89)
I have a student interested in doing Fourier Analysis on Data collected
on a UNIX PC (7300/3B1) voice board. I have the Applications Programmer
kit and manuals, but they said that the A/D coding is proprietary.
Is this really still true? I will try some contacts at AT&T* if this
fails.
Jim Heliotis
{allegra,seismo}!rochester!ritcv!jeh
jeh@CS.RIT.EDU
*I'm talking legitimate transfer (not sneaking out secrets!)gwr@nz8r.UUCP (Gregory W. Ratcliff) (12/18/89)
If the method of data conversion is "discovered" for the Unixpc
voice board, I would sure like to hear about it.
gwr
--
Gregory W. Ratcliff, {osu-cis}n8emr!oink!nz8r!gwr
ham radio,aviation,tcp-ip,unix-pcs.gil@limbic.UUCP (Gil Kloepfer Jr.) (12/19/89)
In article <1761@ultb.isc.rit.edu> jeh@CS.rit.edu (J.E. Heliotis) writes: >I have a student interested in doing Fourier Analysis on Data collected >on a UNIX PC (7300/3B1) voice board. I have the Applications Programmer >kit and manuals, but they said that the A/D coding is proprietary. > >Is this really still true? I will try some contacts at AT&T* if this >fails. > Jim Heliotis > {allegra,seismo}!rochester!ritcv!jeh > jeh@CS.RIT.EDU I've contacted *the* people at AT&T who know about such things, and yes, indeed, it *is* proprietary. They are not permitted to give out any of the gut information about the internals of how the voice power system works. There is, however, an excellent reference about voice digitization in general, which shows the 3B1 voice power system in block form. This is the AT&T Technical Journal, Sept/Oct 1986, Vol 65, issue 3. The journal says that back orders can be ordered by calling (800) 432-6000. Warning-- This journal is FULL OF math equations describing digital filters and the like that only someone who is well-versed in this kind of thing will really understand. The text of the journal is techinically-oriented, but generally informative. To be exact, by the way, the A/D coding is *not* the proprietary part of the voice power system. What is proprietary is the DSP used in the compression of the sound (into sub-bands), the firmware on the board, and the format used to store the sound on the 3B1. The codec (which is the part which does the conversion from various PCM forms to analog and vice versa) has information available. My apologies for any mistakes I may have made above (ie. no flames please). I'm hoping that this information is at least 90% correct (as far as I know it is), and that it will be a help to those of you who are curious out there. -------- | Gil Kloepfer, Jr. | ICUS Software Systems/Bowne Management Systems (depending on where I am) | ...ames!limbic!gil
mvadh@cbnews.ATT.COM (andrew.d.hay) (12/20/89)
In article <589@limbic.UUCP> gil@limbic.UUCP (Gil Kloepfer Jr.) writes:
[]
"There is, however, an excellent reference about voice digitization in
"general, which shows the 3B1 voice power system in block form. This
"is the AT&T Technical Journal, Sept/Oct 1986, Vol 65, issue 3. The
"journal says that back orders can be ordered by calling (800) 432-6000.
432-6600. any at&t document can be ordered via this number...
^
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Andrew Hay +------------------------------------------------------+
42 Authority | Zaphod Beeblebrox is now appearing in |
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