Product Overview:
G.729.1 speech/audio codec was standardized by ITU-T in 2006. The codec operates on each 20ms frame of 16-bit speech/audio signals sampled at 8 KHz or 16 KHz and generates a compressed bit-stream having bit-rates in the range of 8 kbps – 32 kbps structured as 12 layers. The layered approach allows the decoder or any other component in the communication system to truncate the bit-stream by removing the higher layers. The base layer, at 8 kbps, is inter-operable with the G.729 codec. The second layer, at 12 kbps, is the narrowband enhancement layer. Bandwidth extension is added in layer three and predictive transform coding based on MDCT improves the quality from layer four to twelve. The encoder has an inherent support for FEC for bit-rates greater than 12 kbps. The decoder supports the G.729B VAD/DTX scheme has an inherent packet loss concealment algorithm. The codec is primarily targeted for wideband VoIP applications.
Salient features (of CouthIT implementation):
Based on ITU-T specification.
Support for decoding G.729B encoded bit-streams.
Support for optional low delay decoding mode, configurable at init-time.
Supports integrated Packet Loss Concealment (PLC) algorithm.
Support for bad frame indication at frame boundary.
ASM/C implementation.
Re-entrant implementation.
C-callable APIs.
Operates on speech signals sampled at 8 KHz or 16 KHz.
Support for 8 kbps – 32 kbps bit-rates.
Support for encoding G.729 compatible bit-streams.
Support for RTP payload format as specified in RFC 4749 and RFC 5459.
The implementation supports both Little-Endian and Big-Endian.
Optional support for xDM APIs.
Scope of Testing:
Tested for bit-exactness with standard as well as a large database of non-standard test vectors.
Module is fully interruptible.
Tested for any illegal memory access by the module.
Tested for compliance with register preservation requirements.
Tested for Input buffer corruption.
Tested for I/O buffer alignment requirements.
Tested for multi-instance implementation.
Tested for 100% code coverage.
Range validation for all the API parameters.
Tested with scratch contamination at frame boundaries.
Tested for packet loss conditions with 5% loss to 25% loss.
ARM implementation validated on OMAP3530 (Cortex-A8) and DM6446/DM6467 (ARM926EJ-S) platforms.
For most current information on the performance specifications and availability of developed implementation on ARM cores, please send in your enquiry to info@couthit.com