Abstract: An efficient encoded representation of a first and a second input audio signal can be derived using correlation information indicating a correlation between the first and the second input audio signals, when a signal characterization information, indicating at least a first or a second, different characteristic of the input audio signal is additionally considered. Phase information indicating a phase relation between the first and the second input audio signals is derived, when the input audio signals have the first characteristic. The phase information and a correlation measure are included into the encoded representation when the input audio signals have the first characteristic, and only the correlation information is included into the encoded representation when the input audio signals have the second characteristic.

Abstract: An upmixer for upmixing a downmix audio signal into an upmixed audio signal describing one or more upmixed audio channels includes a parameter applier configured to apply upmixing parameters to upmix the downmix audio signal in order to obtain the upmixed audio signal. The parameter applier is configured to apply a phase shift to the downmix audio signal to obtain a phase-shifted version of the downmix audio signal, while leaving a decorrelated signal unmodified by the phase shift. The parameter applier is further configured to combine the phase-shifted version of the downmix audio signal with the decorrelated signal to obtain the upmixed audio signal.

Abstract: An apparatus for upmixing a downmix audio signal describing one or more downmix audio channels into an upmixed audio signal describing a plurality of upmixed audio channels includes an upmixer configured to apply temporally variable upmixing parameters to upmix the downmix audio signal in order to obtain the upmixed audio signal. The apparatus also includes a parameter interpolator, wherein the parameter interpolator is configured to obtain one or more temporally interpolated upmix parameters to be used by the upmixer on the basis of a first complex-valued upmix parameter and a subsequent second complex-valued upmix parameter.

Abstract: An apparatus for upmixing a downmix audio signal describing one or more downmix audio channels into an upmixed audio signal describing a plurality of upmixed audio channels includes an upmixer and a parameter determinator. The upmixer is configured to apply temporally variable upmix parameters to upmix the downmix audio signal in order to obtain the upmixed audio signal, wherein the temporally variable upmix parameters include temporally variable smoothened phase values. The parameter determinator is configured to obtain one or more temporally smoothened upmix parameters for usage by the upmixer on the basis of a quantized upmix parameter input information. The parameter determinator is configured to combine a scaled version of a previous smoothened phase value with a scaled version of an input phase information using a phase change limitation algorithm, to determine a current smoothened phase value on the basis of the previous smoothened phase value and the phase input information.

Abstract: An apparatus and a method for generating a multi-channel synthesizer control signal, a multi-channel synthesizer, a method of generating an output signal from an input signal and a machine-readable storage medium are provided. On an encoder-side, a multi-channel input signal is analyzed for obtaining smoothing control information, which is to be used by a decoder-side multi-channel synthesis for smoothing quantized transmitted parameters or values derived from the quantized transmitted parameters for providing an improved subjective audio quality in particular for slowly moving point sources and rapidly moving point sources having tonal material such as fast moving sinusoids.

Abstract: On an encoder-side, a multi-channel input signal is analyzed for obtaining smoothing control information, which is to be used by a decoder-side multi-channel synthesis for smoothing quantized transmitted parameters or values derived from the quantized transmitted parameters for providing an improved subjective audio quality in particular for slowly moving point sources and rapidly moving point sources having tonal material such as fast moving sinusoids.

Abstract: An efficient encoded representation of a first and a second input audio signal can be derived using correlation information indicating a correlation between the first and the second input audio signals, when a signal characterization information, indicating at least a first or a second, different characteristic of the input audio signal is additionally considered. Phase information indicating a phase relation between the first and the second input audio signals is derived, when the input audio signals have the first characteristic. The phase information and a correlation measure are included into the encoded representation when the input audio signals have the first characteristic, and only the correlation information is included into the encoded representation when the input audio signals have the second characteristic.

Abstract: A selected channel of a multi-channel signal represented by frames composed from sampling values having a high time resolution is provided that can be encoded with higher quality when a wave form parameter representation representing a wave form of an intermediate resolution representation of the selected channel is derived. The wave form parameter representation with the intermediate resolution can be used to shape a reconstructed channel to retrieve a channel having a signal envelope close to a selected original channel. The time scale on which the shaping is performed is shorter than the time scale of a framewise processing, thus enhancing the quality of the reconstructed channel. On the other hand, the shaping time scale is larger than the time scale of the sampling values, significantly reducing the amount of data needed by the wave form parameter representation.

Abstract: For calculating a fingerprint of an audio signal, the audio signal is divided (104a) into subsequent blocks of samples. For the subsequent blocks, one fingerprint value each is calculated (104b), wherein fingerprint samples of subsequent blocks are compared (806). Based on whether the fingerprint value of a block is higher than the fingerprint value of a subsequent block or not, a binary value is assigned, wherein information about a sequence of binary values is output (104c) as fingerprint for the audio signal.

Abstract: A selected channel of a multi-channel signal which is represented by frames composed from sampling values having a high time resolution can be encoded with higher quality when a wave form parameter representation representing a wave form of an intermediate resolution representation of the selected channel is derived, the wave form parameter representation including a sequence of intermediate wave form parameters having a time resolution lower than the high time resolution of the sampling values and higher than a time resolution defined by a frame repetition rate. The wave form parameter representation with the intermediate resolution can be used to shape a reconstructed channel to retrieve a channel having a signal envelope close to that one of the selected original channel. The time scale on which the shaping is performed is shorter than the time scale of a framewise processing, thus enhancing the quality of the reconstructed channel.

Abstract: For time synchronization of a data stream with multi-channel additional data and a data stream with data on at least one base channel, a fingerprint information calculation is performed on the encoder side for the at least one base channel to insert the fingerprint information into a data stream in time connection to the multi-channel additional data. On the decoder side, fingerprint information are calculated from the at least one base channel and used together with the fingerprint information extracted from the data stream to calculate and compensate a time offset between the data stream with the multi-channel additional information and the data stream with the at least one base channel, for example by means of a correlation, to obtain a synchronized multi-channel representation.

Abstract: For synchronizing multichannel extension data with an audio signal, wherein the audio signal includes block division information and the multichannel extension data include reference audio signal fingerprint information, the block division information in the audio signal is detected by means of a block detector. Thereupon, block division of the audio signal is performed by a fingerprint calculator according to the block division information in order to obtain a sequence of test audio signal fingerprints. In addition to that, a sequence of reference audio signal fingerprints is extracted from the reference audio signal fingerprint information of the multichannel extension data. Both sequences of fingerprints are correlated in order to obtain a correlation result, by which a compensator is controlled in order to reduce or eliminate a time offset between the multichannel extension data and the audio signal.

Abstract: An apparatus for generating at least one audio output signal representing a superposition of at least two different audio objects comprises a processor for processing an audio input signal to provide an object representation of the audio input signal, where this object representation can be generated by a parametrically guided approximation of original objects using an object downmix signal. An object manipulator individually manipulates objects using audio object based metadata referring to the individual audio objects to obtain manipulated audio objects. The manipulated audio objects are mixed using an object mixer for finally obtaining an audio output signal having one or several channel signals depending on a specific rendering setup.

Abstract: For time synchronization of a data stream with multi-channel additional data and a data stream with data on at least one base channel, a fingerprint information calculation is performed on the encoder side for the at least one base channel to insert the fingerprint information into a data stream in time connection to the multi-channel additional data. On the decoder side, fingerprint information are calculated from the at least one base channel and used together with the fingerprint information extracted from the data stream to calculate and compensate a time offset between the data stream with the multi-channel additional information and the data stream with the at least one base channel, for example by means of a correlation, to obtain a synchronized multi-channel representation.

Abstract: On an encoder-side, a multi-channel input signal is analyzed for obtaining smoothing control information, which is to be used by a decoder-side multi-channel synthesis for smoothing quantized transmitted parameters or values derived from the quantized transmitted parameters for providing an improved subjective audio quality in particular for slowly moving point sources and rapidly moving point sources having tonal material such as fast moving sinusoids.

Abstract: When encoding an audio signal, the audio signal is first encoded with the first encoder to obtain a first encoder output signal. This first encoder output signal is written into a bit stream. It is further decoded by a decoder to provide a decoded audio signal. The decoded audio signal is compared with the original audio signal to obtain a residual signal. The residual signal is then encoded via a second encoder to provide a second encoder output signal which is also written into a bit stream. The first encoder has a first time or frequency resolution. The second encoder has a second time or frequency resolution. The first resolution differs from the second resolution, so that in a respective decoder, an audio signal with both a high time resolution as well as a high frequency resolution can be retrieved.

Abstract: A selected channel of a multi-channel signal which is represented by frames composed from sampling values having a high time resolution can be encoded with higher quality when a wave form parameter representation representing a wave form of an intermediate resolution representation of the selected channel is derived, the wave form parameter representation including a sequence of intermediate wave form parameters having a time resolution lower than the high time resolution of the sampling values and higher than a time resolution defined by a frame repetition rate. The wave form parameter representation with the intermediate resolution can be used to shape a reconstructed channel to retrieve a channel having a signal envelope close to that one of the selected original channel. The time scale on which the shaping is performed is shorter than the time scale of a framewise processing, thus enhancing the quality of the reconstructed channel.

Abstract: When encoding an audio signal, the audio signal is first encoded with the first encoder to obtain a first encoder output signal. This first encoder output signal is written into a bit stream. It is further decoded by a decoder to provide a decoded audio signal. The decoded audio signal is compared with the original audio signal to obtain a residual signal. The residual signal is then encoded via a second encoder to provide a second encoder output signal which is also written into a bit stream. The first encoder has a first time or frequency resolution. The second encoder has a second time or frequency resolution. The first resolution differs from the second resolution, so that in a respective decoder, an audio signal with both a high time resolution as well as a high frequency resolution can be retrieved.