Patent ID: 8095359

Claim:
A method for encoding an input signal comprising: transforming the input signal into a frequency domain via a first forward transform, wherein: the first forward transform applied to first-length sections of the input signal and, using adaptive switching of a temporal resolution, is followed by quantization and entropy encoding of values of the resulting frequency domain bins; the first forward transform and a second forward transform are a MDCT transform, an integer MDCT transform, a DCT-4 transform, or a DCT transform; adaptively controlling the temporal resolution by performing a second forward transform following the first forward transform, wherein: the second forward transform is applied to second-length sections of the transformed first-length sections; and the second-length sections are smaller than the first-length sections and either output values of the first forward transform or output values of the second forward transform are processed in the quantization and entropy encoding; prior to the transforms at encoding side, the amplitude values of the first-length sections and the second-length sections are weighted using window functions, and overlap-add processing for the first-length sections and second-length sections is applied, and wherein for transitional windows the amplitude values are weighted using asymmetric window functions, and wherein for the second-length sections start and stop window functions are used; and control of the switching, quantization and/or entropy encoding is derived from a psychoacoustic analysis of the input signal; and attaching to an encoded output signal corresponding temporal resolution control information as side information.