faq

LPC 2.4kbps codec meeting Federal Standard 1016 CELP implementation

    Information on 2400 bps LPC and 4800 bps CELP speech coders
    for Frequently Asked Questions lists (audio-formats, comp.compression)

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 (on DOS
diskettes, but configured to compile on Sun SPARC stations) from NTIS
and DTIC.  Example input and processed speech files are included.  A
Technical Information Bulletin (TIB), "Details to Assist in
Implementation of Federal Standard 1016 CELP," 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 also available.

This is available through the National Technical Information Service:

NTIS
U.S. Department of Commerce
5285 Port Royal Road
Springfield, VA  22161
USA
[phone]

The "AD" ordering number for the CELP software is AD M000 118
(US$ 90.00) and for the TIB it's AD A256 629 (US$ 17.50).  The LPC-10
standard, described below, is FIPS Pub 137 (US$ 12.50).  There is a
$3.00 shipping charge on all U.S. orders.  The telephone number for
their automated system is 703-487-4650, or 703-487-4600 if you'd prefer
to talk with a real person.

(U.S. DoD personnel and contractors can receive the package from the
Defense Technical Information Center:  DTIC, Building 5, Cameron
Station, Alexandria, VA 22304-6145.  Their telephone number is
703-274-7633.)

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 (LPC-10) was republished as a Federal
Information Processing Standards Publication 137 (FIPS Pub 137).
It 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 standard
"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$ 5.00 each from:
 
GSA Federal Supply Service Bureau
Specification Section, Suite 8100
470 E. L'Enfant Place, S.W.
Washington, DC  20407
[phone]

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
USA
1-617-275-3733
1-617-275-4323 (fax)
[e-mail]
 
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).
 
DSP Research                
1095 E. Duane Ave.          
Sunnyvale, CA  94086        
USA
[phone]               
[phone] (fax)