摘要:
The temporal envelope of a decorrelated signal derived from an original signal can be shaped without introducing additional distortion, when a spectral flattener is used to spectrally flatten the spectrum of the decorrelated signal and the original signal prior to using the flattened spectra for deriving a gain factor describing the energy distribution between the flattened spectra, and when the so derived gain factor is used by an envelope shaper to timely shape the envelope of the decorrelated signal .
摘要:
An apparatus for generating an enhanced signal from an input signal (600), wherein the enhanced signal has spectral values for an enhancement spectral region, the spectral values for the enhancement spectral regions not being contained in the input signal (600), comprises a mapper (602) for mapping a source spectral region of the input signal to a target region in the enhancement spectral region, the source spectral region comprising a noise-filling region (302); and a noise filler (604) configured for generating first noise values for the noise-filling region (302) in the source spectral region of the input signal and for generating second noise values for a noise region in the target region, wherein the second noise values are decorrelated from the first noise values or for generating second noise values for a noise region in the target region, wherein the second noise values are decorrelated from first noise values in the source region.
摘要:
For a bandwidth extension of an audio signal, in a signal spreader the audio signal is temporally spread by a spread factor greater than 1. The temporally spread audio signal is then supplied to a demicator to decimate the temporally spread version by a decimation factor matched to the spread factor. The band generated by this decimation operation is extracted and distorted, and finally combined with the audio signal to obtain a bandwidth extended audio signal. A phase vocoder in the filterbank implementation or transformation implementation may be used for signal spreading.
摘要:
A schematic block diagram of an audio encoder 2 for encoding a multichannel audio signal 4 is shown. The audio encoder comprises a linear prediction domain encoder 6, a frequency domain encoder 8, and a controller 10 for switching between the linear prediction domain encoder 6 and the frequency domain encoder 8. The controller is configured such that a portion of the multichannel signal is represented either by an encoded frame of the linear prediction domain encoder or by an encoded frame of the frequency domain encoder. The linear prediction domain encoder comprises a downmixer 12 for downmixing the multichannel signal 4 to obtain a downmixed signal 14. The linear prediction domain encoder further comprises a linear prediction domain core encoder 16 for encoding the downmix signal and furthermore, the linear prediction domain encoder comprises a first joint multichannel encoder 18 for generating first multichannel information 20 from the multichannel signal 4.