Abstract: Voice trigger. In accordance with a first method embodiment, a long term average audio energy is determined based on a one-bit pulse-density modulation bit stream. A short term average audio energy is determined based on the one-bit pulse-density modulation bit stream. The long term average audio energy is compared to the short term average audio energy. Responsive to the comparing, a voice trigger signal is generated if the short term average audio energy is greater than the long term average audio energy. Determining the long term average audio energy may be performed independent of any decimation of the bit stream.

Abstract: Voice trigger. In accordance with a first method embodiment, a long term average audio energy is determined based on a one-bit pulse-density modulation bit stream. A short term average audio energy is determined based on the one-bit pulse-density modulation bit stream. The long term average audio energy is compared to the short term average audio energy. Responsive to the comparing, a voice trigger signal is generated if the short term average audio energy is greater than the long term average audio energy. Determining the long term average audio energy may be performed independent of any decimation of the bit stream.

Abstract: According to one embodiment of the invention, a method is provided in which a first set of coefficients is generated for performing echo cancellation in a voice-over-packet (VoP) system. Each coefficient is represented by a first number of bits which includes a first portion representing the sign of the respective coefficient and a second portion representing the magnitude of the respective coefficient. The first set of coefficients is compressed to generate a second set of coefficients which requires less memory storage than the first set of coefficients, in which coefficients which have higher values are encoded before coefficients which have lower values until a predetermined compression ratio is satisfied or until all coefficients in the first set have been encoded.

Abstract: According to one embodiment of the invention, a method is provided in which a first set of coefficients is generated for performing echo cancellation in a voice-over-packet (VoP) system. Each coefficient is represented by a first number of bits which includes a first portion representing the sign of the respective coefficient and a second portion representing the magnitude of the respective coefficient. The first set of coefficients is compressed to generate a second set of coefficients which requires less memory storage than the first set of coefficients, in which coefficients which have higher values are encoded before coefficients which have lower values until a predetermined compression ratio is satisfied or until all coefficients in the first set have been encoded.

Abstract: According to one embodiment of the invention, an apparatus is provided which includes an encoder to encode input speech signals. The speech signals contain frames of talk spurts and silence gaps. The apparatus further includes a voice activity detector coupled to the encoder, the voice activity detector to detect whether a current frame of the input speech signals is the first active frame of a talk spurt. In response to the voice activity detector detecting that the current frame is the first active frame of a talk spurt, the encoder is reset and the encoder states are initialized.