G.729
CS-ACELP Voice Coder
by D2 Technologies, Inc.

Software Overview

D2's G.729 CS-ACELP voice coder algorithm module implements the ITU-T G.729 voice coder standard. 
It compresses codec or linear data to 8-kbps code using the Conjugate-Structure 
Algebraic-Code-Excited Linear-Predictive Coding Algorithm.
Designed to the VP Open interface, the G.729 voice coder module easily integrates with other VP 
Open modules, runs in real-time concurrently with other VP Open modules, and handles any number of 
voice ports assigned to the DSP. Like all of D2's algorithm modules, the G.729 voice coders 
consists of robust software that is rigorously tested.

Features and Benefits

•	Compresses 8-kHz codec or linear voice data to 8 kbps
•	Verified with the G.729 test vector to guarantee inter-operability with other G.729 coders
•	Complies with ITU G.729 coding standard

Processor and System Specifications

•	Devices supported: TMS320C2xx, TMS320C5x
•	Algorithm category: Vocoder
•	Processor resource required:
TMS320C2xx (Est.)
TMS320C5x (Est.)
Program memory
10 kwords
8 kwords
Data memory/voice port
0.5 kwords
0.5 kwords
Processor loading
worst case
Encoder: 30 MIPS
Decoder: 2 MIPS
Encoder: 24 MIPS
Decoder: 2 MIPS

Usage Limitations or Performance Considerations

•	The host, voice data input and output, memory allocation, and module to module communication 
interfaces must conform to VP Open as described in the VP Open Software Interface Specification.

Algorithm Verification

D2's G.729 algorithm module is validated through the following suite of tests:
•	ITU G.729 test vectors – includes test sequences of voice data and other test signals under 
consideration
•	Numerical stability tests with tones and extreme values
•	Code error test with stationary and non-stationary errors
•	Mean Opinion Scores (MOS) test according to ITU-T P.80 specification for Absolute Category Rating
•	VP Open interface validation – D2's G.729 module is integrated with other VP Open modules and 
tested in real-time on the D2 VDS50 system

Availability

Will be available for the TMS320C5x and TMS320C2xx 2Q 1996. A demonstration package will be 
available for the Texas Instruments EVM50 DSP board.

Company Background and Contact Information

D2 Technologies, Inc. was founded by David Y. Wong and David M. Lindsay to help companies innovate 
telecommunications and information products with voice processing technology, which include 
telephony and voice algorithms, real-time system software, and development services.
With over 20 years of experience D2's business model is to develop close partnerships with its 
customers via high levels of service and special engineering to ensure mutual success.
Contact:	D2 Technologies, Inc.
		Attn:  Product Sales
		104 West Anapamu Street
		Suite J
		Santa Barbara,  CA 93101
		(805) 564-3424
		Fax:  (805) 966-2144
		e-mail:  sales@d2tech.com