Abstract: An apparatus for modifying an input audio signal has an excitation determiner, a storage device and a signal modifier. The excitation determiner determines a value of an excitation parameter of a subband of a plurality of subbands of the input audio signal based on an energy content of the subband. Further, the storage device stores a lookup table containing a plurality of spectral weighting factors. A spectral weighting factor of the plurality of spectral weighting factors is associated to a predefined value of the excitation parameter and a subband of the plurality of subbands. The storage device provides a spectral weighting factor corresponding to the determined value of the excitation parameter and corresponding to the subband, the value of the excitation parameter is determined for. Further, the signal modifier modifies a content of the subband of the audio signal, the value of the excitation parameter is determined for, based on the provided spectral weighting factor to provide a modified subband.

Abstract: An apparatus for generating an ambient signal from an audio signal includes a compressor for lossy compression of a representation of the audio signal so as to obtain a compressed representation of the audio signal describing a compressed audio signal. The apparatus for generating the ambient signal further includes a calculator for calculating a difference between the compressed representation of the audio signal and the representation of the audio signal so as to obtain a discrimination representation. The apparatus further includes a provider for providing the ambient signal using the discrimination representation. An apparatus for deriving a multi-channel audio signal from an audio signal includes an apparatus for generating an ambient signal from an audio signal, an apparatus for providing the audio signal as a front-loudspeaker signal and an apparatus for providing the ambient signal as a back-loudspeaker signal.

Abstract: In order to analyze an information signal, a significant short-time spectrum is extracted from the information signal, the means for extracting being configured to extract such short-time spectra which come closer to a specific characteristic than other short-time spectra of the information signal. The short-time spectra extracted are then decomposed into component signals using ICA analysis, a component signal spectrum representing a profile spectrum of a tone source which generates a tone corresponding to the characteristic sought for. From a sequence of short-time spectra of the information signal and from the profile spectra determined, an amplitude envelope is eventually calculated for each profile spectrum, the amplitude envelope indicating how a profile spectrum of a tone source all in all changes over time.

Abstract: An apparatus for processing an audio signal to obtain control information for a speech enhancement filter has a feature extractor for extracting at least one feature per frequency band of a plurality of frequency bands of a short-time spectral representation of a plurality of short-time spectral representations, where the at least one feature represents a spectral shape of the short-time spectral representation in the frequency band. The apparatus additionally has a feature combiner for combining the at least one feature for each frequency band using combination parameters to obtain the control information for the speech enhancement filter for a time portion of the audio signal. The feature combiner can use a neural network regression method, which is based on combination parameters determined in a training phase for the neural network.

Abstract: In order to generate a multi-channel signal having a number of output channels greater than a number of input channels, a mixer is used for upmixing the input signal to form at least a direct channel signal and at least an ambience channel signal. A speech detector is provided for detecting a section of the input signal, the direct channel signal or the ambience channel signal in which speech portions occur. Based on this detection, a signal modifier modifies the input signal or the ambience channel signal in order to attenuate speech portions in the ambience channel signal, whereas such speech portions in the direct channel signal are attenuated to a lesser extent or not at all. A loudspeaker signal outputter then maps the direct channel signals and the ambience channel signals to loudspeaker signals which are associated to a defined reproduction scheme, such as, for example, a 5.1 scheme.

Abstract: An apparatus for generating an ambient signal from an audio signal includes a compressor for lossy compression of a representation of the audio signal so as to obtain a compressed representation of the audio signal describing a compressed audio signal. The apparatus for generating the ambient signal further includes a calculator for calculating a difference between the compressed representation of the audio signal and the representation of the audio signal so as to obtain a discrimination representation. The apparatus further includes a provider for providing the ambient signal using the discrimination representation. An apparatus for deriving a multi-channel audio signal from an audio signal includes an apparatus for generating an ambient signal from an audio signal, an apparatus for providing the audio signal as a front-loudspeaker signal and an apparatus for providing the ambient signal as a back-loudspeaker signal.

Abstract: A significant short-time spectrum is extracted from an information signal, the means for extracting being configured to extract such short-time spectra which come closer to a specific characteristic than others. The short-time spectra extracted are then decomposed into component signals using ICA analysis, a component signal spectrum representing a profile spectrum of a tone source which generates a tone corresponding to the characteristic sought. From a sequence of short-time spectra of the information signal and from the profile spectra determined, an amplitude envelope is calculated for each profile spectrum to indicate how a tone source profile spectrum changes over time. The profile spectra and all the amplitude envelopes associated therewith provide a description of the information signal which may be evaluated further, for example for transcription purposes in the case of a music signal.

Abstract: An apparatus for extracting an ambient signal from an input audio signal comprises a gain-value determinator configured to determine a sequence of time-varying ambient signal gain values for a given frequency band of the time-frequency distribution of the input audio signal in dependence on the input audio signal. The apparatus comprises a weighter configured to weight one of the sub-band signals representing the given frequency band of the time-frequency-domain representation with the time-varying gain values, to obtain a weighted sub-band signal. The gain-value determinator is configured to obtain one or more quantitative feature-values describing one or more features of the input audio signal and to provide the gain-value as a function of the one or more quantitative feature values such that the gain values are quantitatively dependent on the quantitative values.

Abstract: An encoded rhythmic pattern has several groups of velocity values, wherein the velocity values are sorted, such that the groups are included in sequence in an encoded rhythmic pattern. Now, the velocity values concentrated at the beginning of the encoded rhythmic pattern have a higher importance for characterizing the rhythmic gist of a piece of music than velocity values included in additional groups of velocity values. By using such an encoded rhythmic pattern, an efficient database access can be performed.

Abstract: For characterizing a tone signal a sequence of quantized entry times for each of at least two tone sources over time is provided on the basis of a quantization raster. Hereupon, a common period length underlying the at least two tone sources is determined using the sequences of entry times. Hereupon, the sequence of entry times is divided into respective sub-sequences, wherein a length of a sub-sequence is equal to the common period length. Finally, the sub-sequences for the first tone source are combined into a first combined sub-sequence and for the second tone source into a second combined sub-sequence, i.e. for example using a pattern histogram, in order to characterize the tone signal by the first combined sub-sequence and by the second combined sub-sequence, e.g. with regard to rhythm, speed or genre.

Abstract: An encoded rhythmic pattern has several groups of velocity values, wherein the velocity values are sorted, such that the groups are included in sequence in an encoded rhythmic pattern. Now, the velocity values concentrated at the beginning of the encoded rhythmic pattern have a higher importance for characterizing the rhythmic gist of a piece of music than velocity values included in additional groups of velocity values. By using such an encoded rhythmic pattern, an efficient database access can be performed.

Abstract: An encoded rhythmic pattern has several groups of velocity values, wherein the velocity values are sorted, such that the groups are included in sequence in an encoded rhythmic pattern. Now, the velocity values concentrated at the beginning of the encoded rhythmic pattern have a higher importance for characterizing the rhythmic gist of a piece of music than velocity values included in additional groups of velocity values. By using such an encoded rhythmic pattern, an efficient database access can be performed.

Abstract: An encoded rhythmic pattern has several groups of velocity values, wherein the velocity values are sorted, such that the groups are included in sequence in an encoded rhythmic pattern. Now, the velocity values concentrated at the beginning of the encoded rhythmic pattern have a higher importance for characterizing the rhythmic gist of a piece of music than velocity values included in additional groups of velocity values. By using such an encoded rhythmic pattern, an efficient database access can be performed.

Abstract: For analyzing an information signal consisting of a superposition of partial signals, wherein a partial signal originates from an individual source, the information signal is first decomposed into several component signals. Then one or more features are calculated for each component signal, wherein the feature(s) is/are defined so that it/they provide(s) a statement on an information content of the component signal. Finally, an association of the component signals with at least two subspaces is performed on the basis of the features calculated for the component signals. By feature extraction on the component signal level, an efficient subspace decomposition which is meaningful with respect to a present audio scene is achieved.

Abstract: An apparatus for analyzing an audio signal with regard to rhythm information of the audio signal by using an autocorrelation function comprises a filter bank for separating the audio signal into at least two sub-band signals. The sub-band signals are examined with regard to periodicities by an autocorrelation function, to obtain rhythm raw-information for the at least two sub-band signals. To reduce or eliminate the ambiguities of the autocorrelation function for periodical signals, the rhythm raw-information is postprocessed to obtain post-processed rhythm raw-information for the sub-band signal. The rhythm information of the audio signal is established based on the postprocessed rhythm raw-information.

Abstract: In order to analyze an information signal, a significant short-time spectrum is extracted from the information signal, the means for extracting being configured to extract such short-time spectra which come closer to a specific characteristic than other short-time spectra of the information signal. The short-time spectra extracted are then decomposed into component signals using ICA analysis, a component signal spectrum representing a profile spectrum of a tone source which generates a tone corresponding to the characteristic sought for. From a sequence of short-time spectra of the information signal and from the profile spectra determined, an amplitude envelope is eventually calculated for each profile spectrum, the amplitude envelope indicating how a profile spectrum of a tone source all in all changes over time.

Abstract: For characterizing a tone signal a sequence of quantized entry times for each of at least two tone sources over time is provided on the basis of a quantization raster. Hereupon, a common period length underlying the at least two tone sources is determined using the sequences of entry times. Hereupon, the sequence of entry times is divided into respective sub-sequences, wherein a length of a sub-sequence is equal to the common period length. Finally, the sub-sequences for the first tone source are combined into a first combined sub-sequence and for the second tone source into a second combined sub-sequence, i.e. for example using a pattern histogram, in order to characterize the tone signal by the first combined sub-sequence and by the second combined sub-sequence, e.g. with regard to rhythm, speed or genre.

Abstract: In a method of extracting a signal identifier from a time signal, the temporal occurrence of signal edges in the time signal is detected (12), wherein a signal edge has a specified temporal length. In addition, the temporal interval between two selected detected signal edges is determined (14). From the temporal interval determined, a frequency value is calculated (16), the frequency value being associated with a time of occurrence of the frequency value in the time signal so as to obtain a coordinate tuple from the frequency value and the time of occurrence for this frequency value. A signal identifier is created from a plurality of coordinate tuples (18), each coordinate tuple including a frequency value and a time of occurrence, which is why the signal identifier includes a sequence of signal identifier values reproducing the temporal form of the time signal. The extracted signal identifier is based on signal edges of the time signal and thus reproduces the temporal form of the time signal.

Abstract: An apparatus for analyzing an audio signal with regard to rhythm information of the audio signal by using an autocorrelation function comprises a filter bank for separating the audio signal into at least two sub-band signals. The sub-band signals are examined with regard to periodicities by an autocorrelation function, to obtain rhythm raw-information for the at least two sub-band signals. To reduce or eliminate the ambiguities of the autocorrelation function for periodical signals, the rhythm raw-information is postprocessed to obtain post-processed rhythm raw-information for the sub-band signal. The rhythm information of the audio signal is established based on the postprocessed rhythm raw-information.

Abstract: An apparatus for analyzing an audio signal with regard to rhythm information of the audio signal comprises a filterbank for dividing the audio signal into at least two sub-band signals. Every sub-band signal is examined with regard to a periodicity of the sub-band signal to obtain rhythm raw-information of every sub-band signal. The rhythm raw-information is subjected to a quality evaluation to obtain a significance measure for every sub-band signal. The rhythm information of the audio signal will finally be established by considering the significance measure of the sub-band signal and the rhythm raw-information. This enables a more robust analysis of the audio signal, since sub-band signals, where significant rhythm information are present, are preferred compared to sub-band signals where less significant rhythm information are present, when establishing the rhythm information.