Patent ID: 6978236
Filing Date: 2005-12-20
Classification: G10L

Abstract:
1. A method for spectral envelope encoding for an input signal, the input signal having a bandwidth, the bandwidth including certain frequency regions, the input signal being represented by a source encoded version thereof, the source encoded version having a bandwidth not including the certain frequency regions, a spectral envelope of the input signal in the certain frequency regions being representable by a coarse spectral envelope representation and a fine spectral envelope representation, the fine spectral envelope representation being a residual signal, comprising the following steps: performing a statistical analysis of the input signal; based on an outcome of the statistical analysis, generating data on the coarse spectral envelope representation for the certain frequency regions by sampling the spectral envelope in the certain frequency regions with a varying time resolution or a varying frequency resolution, wherein a time resolution or a frequency resolution selected for a time instant depends on the outcome of the statistical analysis of the input signal at the time instant; generating a control signal describing the varying time resolution or the varying frequency resolution; and generating an encoded input signal by multiplexing the source encoded version, the data on the coarse spectral envelope representation and the control signal, wherein the encoded input signal does not include the residual signal.