Learn More
The recently standardized 3GPP codec for Enhanced Voice Services (EVS) offers new features and improvements for low-delay real-time communication systems. Based on a novel, switched low-delay speech/audio codec, the EVS codec contains various tools for better compression efficiency and higher quality for clean/noisy speech, mixed content and music,(More)
Discontinuous Transmission (DTX) is an efficient way to drastically reduce the transmission rate of a communication codec in the absence of voice input. In this mode, most frames that are determined to consist of background noise only are dropped from transmission and replaced by some Comfort Noise Generation (CNG) in the decoder. In this paper, we propose(More)
At low bit-rates, speech coders relying on a single source model have difficulties to properly render speech and background noise simultaneously. Difficulties can get even bigger when using speech enhancement techniques within the coding scheme: these have shown to improve quality for clean speech, but introduce unpleasant instabilities under noisy(More)
CT-aacPlus is a combination of Spectral Band Replication (SBR) technology – a bandwidth-extension tool developed by Coding Technologies (CT) in Germany – with the MPEG Advanced Audio Coding (AAC) technology which, to date, has been one of the most efficient traditional perceptual audio-coding schemes. CT-aacPlus is able to deliver high-quality audio signals(More)
  • 1