Telefonaktiebolaget Lm Ericsson (publ)

Google Inc.

Global IP Solutions, Inc.

Global IP Solutions (gips) Ab

Bastiaan Kleijn

Roar Hagen

Erik Ekudden

Soren Andersen

Soren Vang Andersen

Mattias Nilsson

The present invention relates to improvements of predictive encoding/decoding operations performed on a signal which is transmitted over a packet switched network. The signal is encoded on a block by block basis in such way that a block A-B is predictive encoded independently of any preceding blocks. A start statelocated somewhere between the end boundaries A and B of the block is encoded using any applicable coding method. Both block parts surrounding the start state is then predictive encoded based on the start state and in opposite directions with respect to each other, thereby resulting in a full encoded representationof the block A-B. At the decoding end, corresponding decoding operations are performed.

Low bit rate codec

The present invention relates to improvements of predictive encoding/decoding operations performed on a signal which is transmitted over a packet switched network. The signal is encoded on a block by block basis in such way that a block A-B is predictive encoded independently of any preceding blocks. A start state () located somewhere between the end boundaries A and B of the block is encoded using any applicable coding method. Both block parts surrounding the start state is then predictive encoded based on the start state and in opposite directions with respect to each other, thereby resulting in a full encoded representation () of the block A-B. At the decoding end, corresponding decoding operations are performed.

A solution for improving the perceived sound quality of a decoded acoustic signal is accomplished by extending the spectrum of a received narrow-band acoustic signal (a). A wide-band acoustic signal (A) is produced by extracting at least one essential attribute (z) from the narrow-band acoustic signal (a). Parameters, e.g., representing signal energies, with respect to wide-band frequency components outside the spectrum (A) of the narrow-band acoustic signal (a), are estimated based on the at least one essential attribute (z). This estimation involves allocating a parameter value to a wide-band frequency component, based on a corresponding confidence level.

Bandwidth extension of acoustic signals

At a transmitter of a communication system, a target signal and a primary coded signal are produced in response to an input signal. The primary coded signal is intended to match the target signal. Also produced is encoded enhancement information indicative of how closely the primary coded signal matches the target signal. At a receiver, the primary coded signal is reconstructed, the encoded enhancement information is decoded, and an enhanced reconstructed signal is produced by applying the decoded enhancement information to the reconstructed primary coded signal.

Enhanced coding to improve coded communication signals

A post-processing method for a speech decoder which outputs a decoded speech signal in the time domain provides high frequency resolution based on a frequency spectrum having non-harmonic and noise deficiencies. This is obtained by transforming the decoded time domain signal to a frequency domain signal by using a high frequency resolution transform (FFT). Then an analysis of the energy distribution of the frequency domain signal is made throughout its frequency area (4 kHz) to find the disturbing frequency components and to prioritize such frequency components which are situated in the higher part of the frequency spectrum. Next, the suppression degree for the disturbing frequency components is found based on prioritizing. Finally the steps of controlling a post-filtering of the transform in dependence of the finding, and inverse transforming the post-filtered transform in order to obtain a post-filtered decoded speech signal in the time domain are performed.

Growing community of inventors

Stocksund, Sweden

Bastiaan Kleijn