TIME WARP ACTIVATION SIGNAL PROVIDER, AUDIO SIGNAL ENCODER, METHOD FOR PROVIDING A TIME WARP ACTIVATION SIGNAL, METHOD FOR ENCODING AN AUDIO SIGNAL AND COMPUTER PROGRAMS

摘要

The invention relates to an Audio encoder for encoding an audio signal, comprising: a time warper (506); a time- frequency converter (508) for performing a time/frequency conversion of a time warped audio signal into a spectral representation; a quantizer (512) for quantizing audio values, wherein the quantizer is configured to quantize to zero audio values below a quantization threshold; a noise filling calculator (524) for estimating a measure of an energy of audio values quantized to zero for a time frame of the audio signal to obtain a noise filling measure; (p.33, 4-12); an audio signal analyzer (516,520) for analyzing, whether the time frame of the audio signal has a harmonic or speech characteristic; a manipulator (602) for manipulating the noise filling measure depending on a harmonic or a speech characteristic of the audio signal to obtain a manipulated noise filling measure; and an output interface (522) for generating an encoded signal for transmission or storage, the encoded signal comprising the manipulated noise filing measure (530); wherein the manipulator (602) is configured to apply a normal noise level when the signal does not have an harmonic or speech characteristic and when no time warp is applied, and to manipulate the noise filling level to be lower than in the normal case when a pitch contour as found, which indicates a harmonic content, and the time warp is active.