Patent ID: 7596490

Claim:
A method of encoding a signal, the method comprising the steps of: providing a respective set of sampled signal values (x(t)) for each of a plurality of sequential time segments; analyzing the sampled signal values (x(t)) to determine one or more sinusoidal components for each of the plurality of sequential segments, each sinusoidal component including a frequency value (Ω) and a phase value (Ψ); linking sinusoidal components across a plurality of sequential segments to provide sinusoidal tracks; determining, for each sinusoidal track in each of the plurality of sequential segments, a predicted phase value ({tilde over (ψ)}(k)) as a function of phase value for at least a previous segment; determining, for each sinusoidal track, a measured phase value (Ψ) comprising a generally monotonically changing value; selecting, for each track, a number of sinusoids in the track; quantizing, for each track, sinusoidal codes (C S ) as a function of the predicted phase value ({tilde over (ψ)}(k)) and the measured phase value (Ψ) for the segment, where the sinusoidal codes (C S ) are quantized in dependence on (i) the frequencies of the selected sinusoids and (ii) a set of quantization grids that vary from fine to coarse, wherein responsive to frequency values of two sinusoids in a given sinusoidal track having a first difference, the sinusoidal codes (C s ) are quantized using a first quantization grid, and wherein responsive to frequency values of two sinusoids in another given sinusoidal track having a second difference smaller than the first difference, the sinusoidal codes (C s ) are quantized using a second quantization grid finer than or equal to the first quantization grid; and generating an encoded signal (AS) including sinusoidal codes (C S ) representing the frequency and the phase and linking information.