G.728 speech codec was standardized by ITU-T in 1992. The codec operates on 16-bit speech signal sampled at 8 KHz and generates compressed bit-streams with a bit-rate of 16 kbps. It is based on low delay code excited linear prediction (LD-CELP) algorithm. The decoder has an inherent packet loss concealment mechanism. It is used in video conferencing, satellite telephony, and voice over cable applications.
- Based on ITU-T specification.
- Optimized ASM/C implementation.
- Re-entrant implementation.
- C-callable APIs.
- Operates on speech/audio signals sampled at 8 KHz.
- Support for 16 kbps bit-rate.
- Support for configurable frame sizes in multiples of 2.5 ms.
- Support for RTP payload format as specified in RFC 3551.
- Support for post-filter option, configurable at init-time.
- Supports integrated Packet Loss Concealment (PLC) algorithm.
- Support for PLC for frame size of the order of 1ms.
- The implementation supports both Little-Endian and Big-Endian (on C64x platform)
- Optional support for xDM APIs on TI platforms.
- Tested for bit-exactness with standard as well as a large database of non-standard test vectors.
- Module is fully interruptible (Maximum interrupt latency on C64x is 6000 cycles).
- Tested for any illegal memory access by the module (C64x)
- 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.
- TI C55x implementation validated on Spectrum Digital C5510 DSK.
- TI C64x+ implementation validated on Spectrum Digital C6455 DSK.
TI C55x, TI C64x+., and TI C66x.