Siemens Enterprise Communications Gmbh & Co. Kg

Siemens Aktiengesellschaft

Unify Gmbh Co. Kg

Herve Taddei

Stefan Schandl

Peter Jax

Bernd Geiser

Panji Setiawan

Peter Vary

Martin Gartner

Aulis Telle

The inventive method provides for an encoder in a voice codec to be designed such that after a particular idle time ('Idle Period') it recalculates the averaged energy and the autocorrelation function. Administrative points in the network inform the encoder about the idle time which has been set in the transmission network.

Method and means for encoding background noise information

To form an audio signal, frequency components of the audio signal which are allotted to a first subband are formed by means of a subband decoder using supplied fundamental period values which respectively indicate a fundamental period for the audio signal. Frequency components of the audio signal which are allotted to a second subband are formed by exciting an audio synthesis filter using an excitation signal which is specific to the second subband. To produce this excitation signal, an excitation signal generator derives a fundamental period parameter from the fundamental period values. The fundamental period parameter is used by the excitation signal generator to form pulses with a pulse shape which is dependent on the fundamental period parameter at an interval of time which is determined by the fundamental period parameter and to mix them with a noise signal.

Method and arrangements for audio signal encoding

A method for the artificial extension of the bandwidth of speech signals involves:

Method and device for the artificial extension of the bandwidth of speech signals

A basic idea of the invention is to ascertain information on the course of the bit rate switching during an active speech phase. According to the invention, during the speech phase, information on the percentage proportion of broadband active speech frames in comparison to narrowband active speech frames is compiled on the part of the decoder. A high percentage proportion of broadband active speech frames indicates that a broadband use is preferred on the part of the codec and therefore a need exists for synthesizing noise information in broadband form during a DTX phase.

Method and means for decoding background noise information

According to the invention, an excitation signal is generated as a result of sampled excitation values in order to excite an audio synthesis filter, the generated sampled excitation values being continuously stored in an adaptive codebook. A noise generator is provided which continuously generates random sampled values. A sequence of the stored sampled excitation values is selected from the adaptive codebook based on a fed audio fundamental frequency parameter by means of which a time gap between the sequence that is to be selected and the actual time reference is predefined. The excitation signal is generated by mixing the selected sequence with a random sequence encompassing actual random sampled valued of the noise generator.

Method and arrangements for coding audio signals

In on aspect, user data is decoded which has been coded as base data and refining data, wherein the base data is decoded using a first delay and the refining data is decoded using a second delay which is longer than the first delay. Furthermore, a check establishes whether the refining data is available in accordance with a time parameter. If the check result is positive, the decoded base data is additionally delayed, the additionally delayed decoded base data is mixed with the decoded refining data, and resulting mixed data is output as user data. If the check result is negative, however, the decoded base data is output as user data.

Growing community of inventors

Bonn, Germany

Herve Taddei