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Figuring out ZyXEL's CELP specs



   After various people expressed interest in the ZyXEL modem CELP specs...

[email protected] replied:
> As far as CELP, ZyXEL will not be releasing the specs.

   OK.  In that case, it's up to us to figure it out.  :-)  I saw the
following post about 4800 CELP on another newsgroup and thought it might help
someone here get closer to figuring out how ZyXEL's 9600 CELP works.

PLEASE: the following message mentions a source of CELP source code that's
	free.  Rather than everyone calling all at once, I suggest:

  (1) If you live in the D.C. area, maybe go ahead and call anyway and then
      post the results in this newsgroup.

Otherwise
  (2) If you have a high interest and it's likely you'll actually do
      something with the information, POST A NOTE TO THIS NEWSGROUP saying
      so and wait a couple of days so we can all see who else is interested.

  (3) When the dust settles, the most interested, and/or those nearest
      Washington, D.C., call to get the source code and then post it to the
      newsgroup (if permitted).  (Unfortunately, you may have to consider
      U.S. export restrictions, but since the author says the code "is
      available for worldwide distribution", I don't expect this to be a
      problem.)
 -WBE
---------------------------------------------------------------------------
From: [email protected] (Joe Campbell)
Newsgroups: comp.compression.research
Subject: Re: CELP vocoder refs
Date: 17 Jan 93 21:38:07 GMT
Organization: The Great Beyond

Hi,
I hope that the following information answers your questions.
Joe

The U.S. DoD's Federal-Standard-1016 based 4800 bps code excited linear
prediction voice coder version 3.2 (CELP 3.2) Fortran and C simulation
source codes are available for worldwide distribution at no charge (on
DOS diskettes, but configured to compile on Sun SPARC stations) from:

Bob Fenichel
National Communications System
Washington, D.C.  20305
1-703-692-2124
1-703-746-4960 (fax)

Example input and processed speech files, a technical information bulletin,
and the official standard "Federal Standard 1016, Telecommunications:
Analog to Digital Conversion of Radio Voice by 4,800 bit/second Code
Excited Linear Prediction (CELP)" are included at no charge.

The following articles describe the Federal-Standard-1016 4.8-kbps CELP
coder (it's unnecessary to read more than one):
 
Campbell, Joseph P. Jr., Thomas E. Tremain and Vanoy C. Welch,
"The Federal Standard 1016 4800 bps CELP Voice Coder," Digital Signal
Processing, Academic Press, 1991, Vol. 1, No. 3, p. 145-155.
 
Campbell, Joseph P. Jr., Thomas E. Tremain and Vanoy C. Welch,
"The DoD 4.8 kbps Standard (Proposed Federal Standard 1016),"
in Advances in Speech Coding, ed. Atal, Cuperman and Gersho,
Kluwer Academic Publishers, 1991, Chapter 12, p. 121-133.
 
Campbell, Joseph P. Jr., Thomas E. Tremain and Vanoy C. Welch, "The
Proposed Federal Standard 1016 4800 bps Voice Coder:  CELP," Speech
Technology Magazine, April/May 1990, p. 58-64.


The U.S. DoD's Federal-Standard-1015/NATO-STANAG-4198 based 2400 bps
linear prediction coder version 53 (LPC-10e v53) Fortran or C simulation
source codes are available on a limited basis upon written request to:
 
Tom Tremain
Department of Defense
Ft. Meade, MD  20755-6000
USA

The U.S. Federal Standard 1015 (NATO STANAG 4198) is described in:
Thomas E. Tremain, "The Government Standard Linear Predictive Coding
Algorithm:  LPC-10," Speech Technology Magazine, April 1982, p. 40-49.

There is also a section about FS-1015 in the book:
Panos E. Papamichalis, Practical Approaches to Speech Coding,
Prentice-Hall, 1987.

The voicing classifier used in the enhanced LPC-10 (LPC-10e) is described in:
Campbell, Joseph P., Jr. and T. E. Tremain, "Voiced/Unvoiced Classification
of Speech with Applications to the U.S. Government LPC-10E Algorithm,"
Proceedings of the IEEE International Conference on Acoustics, Speech, and
Signal Processing, 1986, p. 473-6.

Copies of the official standards "Federal Standard 1015, ...", and
"Federal Standard 1016, Telecommunications: Analog to Digital Conversion
of Radio Voice by 4,800 bit/second Code Excited Linear Prediction (CELP)"
are available for US$ 2.50 each from:
 
GSA Rm 6654
7th & D St SW
Washington, D.C.  20407
1-202-708-9205

Realtime DSP code for FS-1015 and FS-1016 is sold by:
 
John DellaMorte
DSP Software Engineering
165 Middlesex Tpk, Suite 206
Bedford, MA  01730
1-617-275-3733
1-617-275-4323 (fax)
[email protected]
 
DSP Software Engineering's FS-1016 code can run on a DSP Research's Tiger 30
(a PC board with a TMS320C3x and analog interface suited to development work)
or on Intellibit's AE2000 TMS320C31 based 3" by 2.5" card.
 
DSP Research                Intellibit
1095 E. Duane Ave.          P.O. Box 9785
Sunnyvale, CA  94086        McLean, VA  22102-0785
(408)773-1042               (703)442-4781
(408)736-3451 (fax)         (703)442-4784 (fax)
-- 
.............................................................................
; Dr. Campbell  N3JBC  [email protected]  [email protected] ;
; My opinions are mine!   Happiness = Reality - Expectations, Click & Clack ;
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