Abstract: An audio similarity evaluator obtains envelope signals for a plurality of frequency ranges on the basis of an input audio signal. The audio similarity evaluator is configured to obtain a modulation information associated with the envelope signals for a plurality of modulation frequency ranges, wherein the modulation information describes the modulation of the envelope signals. The audio similarity evaluator is configured to compare the obtained modulation information with a reference modulation information associated with a reference audio signal, in order to obtain an information about a similarity between the input audio signal and the reference audio signal. An audio encoder uses such an audio similarity evaluator. Another audio similarity evaluator uses a neural net trained using the audio similarity evaluator.

Abstract: An apparatus for generating an encoded signal includes: a window sequence controller for generating a window sequence information for windowing an audio or image signal, the window sequence information indicating a first window for generating a first frame of spectral values, a second window function and at least one third window function for generating a second frame of spectral values, wherein the first window function, the second window function and the one or more third window functions overlap within a multi-overlap region; a preprocessor for windowing a second block of samples corresponding to the second window function and the at least one third window functions using an auxiliary window function to acquire a second block of windowed samples, a spectrum converter for applying an aliasing-introducing transform; and a processor for processing the first frame and the second frame to acquire encoded frames of the audio or image signal.

Abstract: An apparatus for generating a decoded two-channel signal includes: an audio processor for decoding an encoded two-channel signal to obtain a first set of first spectral portions; a parametric decoder for providing parametric data for a second set of second spectral portions and a two-channel identification identifying either a first or a second different two-channel representation for the second spectral portions; and a frequency regenerator for regenerating a second spectral portion depending on a first spectral portion of the first set of first spectral portions, the parametric data for the second portion and the two-channel identification for the second portion.

Abstract: A schematic block diagram of a decoder for decoding an encoded audio signal is shown. The decoder includes an adaptive spectrum-time converter and an overlap-add-processor. The adaptive spectrum-time converter converts successive blocks of spectral values into successive blocks of time values, e.g. via a frequency-to-time transform. Furthermore, the adaptive spectrum-time converter receives a control information and switches, in response to the control information, between transform kernels of a first group of transform kernels including one or more transform kernels having different symmetries at sides of a kernel, and a second group of transform kernels including one or more transform kernels having the same symmetries at sides of a transform kernel. Moreover, the overlap-add-processor overlaps and adds the successive blocks of time values to obtain decoded audio values, which may be a decoded audio signal.

Abstract: An apparatus for generating a decoded two-channel signal includes: an audio processor for decoding an encoded two-channel signal to obtain a first set of first spectral portions; a parametric decoder for providing parametric data for a second set of second spectral portions and a two-channel identification identifying either a first or a second different two-channel representation for the second spectral portions; and a frequency regenerator for regenerating a second spectral portion depending on a first spectral portion of the first set of first spectral portions, the parametric data for the second portion and the two-channel identification for the second portion.

Abstract: An apparatus for generating an encoded signal includes: a window sequence controller for generating a window sequence information for windowing an audio or image signal, the window sequence information indicating a first window for generating a first frame of spectral values, a second window function and at least one third window function for generating a second frame of spectral values, wherein the first window function, the second window function and the one or more third window functions overlap within a multi-overlap region; a preprocessor for windowing a second block of samples corresponding to the second window function and the at least one third window functions using an auxiliary window function to acquire a second block of windowed samples, a spectrum converter for applying an aliasing-introducing transform; and a processor for processing the first frame and the second frame to acquire encoded frames of the audio or image signal.

Abstract: A decoder for decoding an encoded audio signal to obtain a phase-adjusted audio signal is provided. The decoder has a decoding unit and a phase adjustment unit. The decoding unit is adapted to decode the encoded audio signal to obtain a decoded audio signal. The phase adjustment unit is adapted to adjust the decoded audio signal to obtain the phase-adjusted audio signal. The phase adjustment unit is configured to receive control information depending on a vertical phase coherence of the encoded audio signal. Moreover, the phase adjustment unit is adapted to adjust the decoded audio signal based on the control information.

Abstract: An apparatus for encoding an audio or image signal, includes: a controllable windower for windowing the audio or image signal to provide the sequence of blocks of windowed samples; a converter for converting the sequence of blocks of windowed samples into a spectral representation including a sequence of frames of spectral values; a transient location detector for identifying a location of a transient within a transient look-ahead region of a frame; and a controller for controlling the controllable windower to apply a specific window having a specified overlap length to the audio or image signal in response to an identified location of the transient, wherein the controller is configured to select the specific window from a group of at least three windows, wherein the specific window is selected based on the transient location.

Abstract: A decoder for decoding a plurality of spectral-domain audio samples is provided. The decoder includes a first decoding module for generating a first group and a second group of time-domain intermediate audio samples from the spectral-domain audio samples. Moreover, the decoder includes an overlap-adder for overlap-adding the first group of time-domain intermediate audio samples with an overlap of more than 5% and at most 50% with the second group of time-domain intermediate audio samples. Furthermore, the decoder includes a second decoding module for generating a third group and a fourth group of time-domain intermediate audio samples from the spectral-domain audio samples. Moreover, the decoder includes an output interface.

Abstract: A cochlear implant for processing signal parameters which are adapted for controlling the cochlear implant, which are based on the audio signal and which enable generating a representation of the audio signal by the cochlear implant includes a receive interface which is implemented to receive the signal parameters and a nerve stimulator for processing the signal parameters to generate nerve cell stimulation signals based on the signal parameters. A device for generating a control signal for a cochlear implant on the basis of an audio signal includes a cochlear parameter extractor for analyzing the audio signal which is implemented to generate signal parameters as input information for the cochlear implant based on an analysis of the audio signal using a human hearing simulation model, and a transmit interface for transmitting the signal parameters to the cochlear implant.

Abstract: A downmixer for downmixing at least two channels of a multichannel signal having the two or more channels includes: a processor for calculating a partial downmix signal from the at least two channels; a complementary signal calculator for calculating a complementary signal from the multichannel signal, the complementary signal being different from the partial downmix signal; and an adder for adding the partial downmix signal and the complementary signal to obtain a downmix signal of the multichannel signal.

Abstract: An apparatus for generating a bandwidth enhanced audio signal from an input audio signal having an input audio signal frequency range includes: a raw signal generator configured for generating a raw signal having an enhancement frequency range, wherein the enhancement frequency range is not included in the input audio signal frequency range; a neural network processor configured for generating a parametric representation for the enhancement frequency range using the input audio frequency range of the input audio signal and a trained neural network; and a raw signal processor for processing the raw signal using the parametric representation for the enhancement frequency range to obtain a processed raw signal having frequency components in the enhancement frequency range, wherein the processed raw signal or the processed raw signal and the input audio signal frequency range of the input audio signal represent the bandwidth enhanced audio signal.

Abstract: An encoder for encoding an audio signal is configured to encode the audio signal in a transform domain or filter-bank domain, is configured to determine spectral coefficients of the audio signal for a current frame and at least one previous frame, and is configured to selectively apply predictive encoding to a plurality of individual spectral coefficients or groups of spectral coefficients which are separated by at least one spectral coefficient.

Abstract: A schematic block diagram of a decoder for decoding an encoded audio signal is shown. The decoder includes an adaptive spectrum-time converter and an overlap-add-processor. The adaptive spectrum-time converter converts successive blocks of spectral values into successive blocks of time values, e.g. via a frequency-to-time transform. Furthermore, the adaptive spectrum-time converter receives a control information and switches, in response to the control information, between transform kernels of a first group of transform kernels including one or more transform kernels having different symmetries at sides of a kernel, and a second group of transform kernels including one or more transform kernels having the same symmetries at sides of a transform kernel. Moreover, the overlap-add-processor overlaps and adds the successive blocks of time values to obtain decoded audio values, which may be a decoded audio signal.

Abstract: An apparatus for encoding an audio or image signal, includes: a controllable windower for windowing the audio or image signal to provide the sequence of blocks of windowed samples; a converter for converting the sequence of blocks of windowed samples into a spectral representation including a sequence of frames of spectral values; a transient location detector for identifying a location of a transient within a transient look-ahead region of a frame; and a controller for controlling the controllable windower to apply a specific window having a specified overlap length to the audio or image signal in response to an identified location of the transient, wherein the controller is configured to select the specific window from a group of at least three windows, wherein the specific window is selected based on the transient location.

Abstract: A downmixer for downmixing at least two channels of a multichannel signal having the two or more channels includes: a processor for calculating a partial downmix signal from the at least two channels; a complementary signal calculator for calculating a complementary signal from the multichannel signal, the complementary signal being different from the partial downmix signal; and an adder for adding the partial downmix signal and the complementary signal to obtain a downmix signal of the multichannel signal.

Abstract: An encoder for encoding an audio signal is configured to encode the audio signal in a transform domain or filter-bank domain, is configured to determine spectral coefficients of the audio signal for a current frame and at least one previous frame, and is configured to selectively apply predictive encoding to a plurality of individual spectral coefficients or groups of spectral coefficients which are separated by at least one spectral coefficient.

Abstract: An apparatus for decoding an encoded audio signal, includes a spectral domain audio decoder for generating a first decoded representation of a first set of first spectral portions, the decoded representation having a first spectral resolution; a parametric decoder for generating a second decoded representation of a second set of second spectral portions having a second spectral resolution being lower than the first spectral resolution; a frequency regenerator for regenerating every constructed second spectral portion having the first spectral resolution using a first spectral portion and spectral envelope information for the second spectral portion; and a spectrum time converter for converting the first decoded representation and the reconstructed second spectral portion into a time representation.

Abstract: An approach is described that obtains spectrum coefficients for a replacement frame of an audio signal. A tonal component of a spectrum of an audio signal is detected based on a peak that exists in the spectra of frames preceding a replacement frame. For the tonal component of the spectrum a spectrum coefficients for the peak and its surrounding in the spectrum of the replacement frame is predicted, and for the non-tonal component of the spectrum a non-predicted spectrum coefficient for the replacement frame or a corresponding spectrum coefficient of a frame preceding the replacement frame is used.

Abstract: An apparatus for generating an encoded signal includes: a window sequence controller for generating a window sequence information for windowing an audio or image signal, the window sequence information indicating a first window for generating a first frame of spectral values, a second window function and at least one third window function for generating a second frame of spectral values, wherein the first window function, the second window function and the one or more third window functions overlap within a multi-overlap region; a preprocessor for windowing a second block of samples corresponding to the second window function and the at least one third window functions using an auxiliary window function to acquire a second block of windowed samples, a spectrum converter for applying an aliasing-introducing transform; and a processor for processing the first frame and the second frame to acquire encoded frames of the audio or image signal.