VAD/CNG

The VAD determines whether or not speech is present in the outbound signal, when speech is not present, the CNG algorithm generates a "comfort" noise signal.

ADT VAD / CNG is available on the following Platforms: Other configurations are available upon request.

Product Number	Platform
adt_vad-cng_c54x	TI TMS320C54x
adt_vad-cng_c55x	TI TMS320C55x
adt_vad-cng_c64x	TI TMS320C64x
adt_vad-cng_c64xp	TI TMS320C64x+
adt_vadcngdll_win32	Win32
adt_vadcnglib_win32	Win32
adt_vad-cng_i686	i686
adt_vad-cng_armM3	Cortex-M3
adt_vad-cng_armM4	Cortex-M4
adt_vad-cng_armA8	Cortex-A8
adt_vad-cng_armA9	Cortex-A9
adt_vad-cng_armA15	Cortex-A15
adt_vad-cng_arm9	ARM9e

DESCRIPTION

Adaptive Digital’s VAD/CNG software performs voice activity detection and comfort noise generation. It is used in systems that used reduced bandwidth channels during silent or non-voiced portions of a conversation. The VAD algorithm is used at the transmit side of a communication link. The VAD determines whether or not speech is present in the outbound signal. If speech is not present, the VAD algorithm determines the level of the background noise. The background noise level is transmitted to the opposite end of the link in place of the speech signal. The noise level requires little channel bandwidth and only needs to be transmitted when the background noise level changes. The CNG algorithm runs at the receive side of the link. When speech is not present, the CNG algorithm generates a noise signal at the level sent from the transmit side.

Applications include Voice-Over-Packet, Satellite, and other digital voice applications.

Data Sheet - .pdf

FEATURES

1. Functions are C-callable.
2. Multi-channel capable
3. Can be used with all types of speech coding
4. Spectrally shaped noise generation

SPECIFICATIONS

TI TMS320C5000

VAD/CNG C54x

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory
VAD	0.36	423	291	26
CNG	0.47

VAD/CNG C55x

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory
VAD	0.28	815	582	52
CNG	0.29

*Loading assumes a 2-frequency signal

 

TI TMS320C6000

VAD/CNG C64x

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory
VAD	0.19	1728	604	64
CNG	0.15

VAD/CNG C64x +

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory
VAD	0.17	1632	604	64
CNG	0.15

 

PC / WINDOWS

VAD/CNG DLL

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory	Scratch Memory
VAD	0.13	2.7K	0	80	0
CNG	0.53				0

VAD/CNG LIB

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory	Scratch Memory
VAD	0.16	2.7K	0	80	0
CNG	0.62				0

 

ARM® DEVICES

VAD/CNG ARM Cortex-A8/A9/A15

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory	Scratch Memory
VAD	0.26	4K	336	80	0
CNG	1.3				0

VAD/CNG ARM Cortex-M3/M4

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory	Scratch Memory
VAD	??	?	?	80	0
CNG	??				0

Contact Sales for specifications: 610-825-0182 x120

VAD/CNG ARM9e

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory	Scratch Memory
VAD	0.22	4K	336	80	0
CNG	1.22				0

 

LINUX

VAD/CNG i686

CPU UTILIZATION & MEMORY REQUIREMENTS
All Memory usage is given in units of 16-bit word.

SOFTWARE	MIPs (Peak)	Program Memory	Data Memory	Per-Channel Data Memory	Scratch Memory
VAD	0.13	2.8K	412	80	0
CNG	0.62				0

 

We specify MIPS (Millions of Instructions per Second) as MCPS (Millions of Instruction Cycles per Second). Unless otherwise specified, peak MIPS are indicated.

FUNCTION

VAD_ADT_vadInitialize (…) Initializes the VAD and CNG modules
VAD_ADT_vad (…) Executes voice activity detector
CNG_ADT_cng (…) Executes comfort noise generator