Audio decoder and method for providing a decoded audio information using an error concealment modifying a time domain excitation signal

A method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises modifying a time domain excitation signal derived from one or more audio frames encoded in frequency domain representation preceding a lost audio frame, in order to acquire the error concealment audio information;
• wherein, for audio frames encoded using the frequency domain representation, the encoded audio information comprises an encoded representation of spectral values and scale factors representing a scaling of different frequency bands.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises modifying a time domain excitation signal derived from one or more audio frames encoded in frequency domain representation preceding a lost audio frame, in order to acquire the error concealment audio information;
• wherein, for audio frames encoded using the frequency domain representation, the encoded audio information comprises an encoded representation of spectral values and scale factors representing a scaling of different frequency bands,
• when said computer program is run by a computer.

An audio decoder for providing a decoded audio information on the basis of an encoded audio information, the audio decoder comprising:

• an error concealment configured to provide an error concealment audio information for concealing a loss of an audio frame,
• wherein the error concealment is configured to modify a time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, in order to acquire the error concealment audio information;
• wherein the error concealment is configured to adjust the speed used to gradually reduce a gain applied to scale the time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, or the one or more copies thereof, in dependence on a result of a pitch analysis or a pitch prediction,
• such that a deterministic component of the time domain excitation signal input into an LPC synthesis is faded out faster for signals comprising a larger pitch change per time unit when compared to signals comprising a smaller pitch change per time unit, and/or
• such that a deterministic component of a time domain excitation signal input into an LPC synthesis is faded out faster for signals for which a pitch prediction fails when compared to signals for which the pitch prediction succeeds.

An audio decoder for providing a decoded audio information on the basis of an encoded audio information, the audio decoder comprising:

• an error concealment configured to provide an error concealment audio information for concealing a loss of an audio frame,
• wherein the error concealment is configured to modify a time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, in order to acquire the error concealment audio information;
• wherein the error concealment is configured to acquire an information about an intensity of a deterministic signal component in one or more audio frames preceding a lost audio frame, and
• wherein the error concealment is configured to compare the information about an intensity of a deterministic signal component in one or more audio frames preceding a lost audio frame with a threshold value, to decide whether to input a deterministic time domain excitation signal with the addition of a noise like time domain excitation signal into an LPC synthesis, or whether to input only a noise time domain excitation signal into the LPC synthesis.

An audio decoder for providing a decoded audio information on the basis of an encoded audio information, the audio decoder comprising:

• an error concealment configured to provide an error concealment audio information for concealing a loss of an audio frame,
• wherein the error concealment is configured to modify a time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, in order to acquire the error concealment audio information;
• wherein the error concealment is configured to acquire a pitch information describing a pitch of the audio frame preceding the lost audio frame, and to provide the error concealment audio information in dependence on the pitch information;
• wherein the error concealment is configured to acquire the pitch information on the basis of the time domain excitation signal associated with the audio frame preceding the lost audio frame.

An audio decoder for providing a decoded audio information on the basis of an encoded audio information, the audio decoder comprising:

• an error concealment configured to provide an error concealment audio information for concealing a loss of an audio frame,
• wherein the error concealment is configured to modify a time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, in order to acquire the error concealment audio information;
• wherein the error concealment is configured to copy a pitch cycle of the time domain excitation signal associated with the audio frame preceding the lost audio frame one time or multiple times, in order to acquire a excitation signal for a synthesis of the error concealment audio information;
• wherein the error concealment is configured to low-pass filter the pitch cycle of the time domain excitation signal associated with the audio frame preceding the lost audio frame using a sampling-rate dependent filter, a bandwidth of which is dependent on a sampling rate of the audio frame encoded in a frequency domain representation.

A method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises adjusting the speed used to gradually reduce a gain applied to scale the time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, or the one or more copies thereof, in dependence on a result of a pitch analysis or a pitch prediction,
• such that a deterministic component of the time domain excitation signal input into an LPC synthesis is faded out faster for signals comprising a larger pitch change per time unit when compared to signals comprising a smaller pitch change per time unit, and/or
• such that a deterministic component of a time domain excitation signal input into an LPC synthesis is faded out faster for signals for which a pitch prediction fails when compared to signals for which the pitch prediction succeeds.

A method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises acquiring an information about an intensity of a deterministic signal component in one or more audio frames preceding a lost audio frame, and
• wherein the method comprises comparing the information about an intensity of a deterministic signal component in one or more audio frames preceding a lost audio frame with a threshold value, to decide whether to input a deterministic time domain excitation signal with the addition of a noise like time domain excitation signal into an LPC synthesis, or whether to input only a noise time domain excitation signal into the LPC synthesis.

A method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises acquiring a pitch information describing a pitch of the audio frame preceding the lost audio frame, and providing the error concealment audio information in dependence on the pitch information;
• wherein the pitch information is acquired on the basis of the time domain excitation signal associated with the audio frame preceding the lost audio frame.

A method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises copying a pitch cycle of the time domain excitation signal associated with the audio frame preceding the lost audio frame one time or multiple times, in order to acquire an excitation signal for a synthesis of the error concealment audio information;
• wherein the method comprises low-pass filtering the pitch cycle of the time domain excitation signal associated with the audio frame preceding the lost audio frame using a sampling-rate dependent filter, a bandwidth of which is dependent on a sampling rate of the audio frame encoded in a frequency domain representation.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises adjusting the speed used to gradually reduce a gain applied to scale the time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, or the one or more copies thereof, in dependence on a length of a pitch period of the time domain excitation signal, such that a deterministic component of time domain excitation signal input into an LPC synthesis is faded out faster for signals comprising a shorter length of the pitch period when compared to signals comprising a larger length of the pitch period,
• when said computer program is run by a computer.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises adjusting the speed used to gradually reduce a gain applied to scale the time domain excitation signal acquired for one or more audio frames preceding a lost audio frame, or the one or more copies thereof, in dependence on a result of a pitch analysis or a pitch prediction,
• such that a deterministic component of the time domain excitation signal input into an LPC synthesis is faded out faster for signals comprising a larger pitch change per time unit when compared to signals comprising a smaller pitch change per time unit, and/or
• such that a deterministic component of a time domain excitation signal input into an LPC synthesis is faded out faster for signals for which a pitch prediction fails when compared to signals for which the pitch prediction succeeds,
• when said computer program is run by a computer.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises time-scaling the time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame, or the one or more copies thereof, in dependence on a prediction of a pitch for the time of the one or more lost audio frames,
• when said computer program is run by a computer.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises acquiring an information about an intensity of a deterministic signal component in one or more audio frames preceding a lost audio frame, and
• wherein the method comprises comparing the information about an intensity of a deterministic signal component in one or more audio frames preceding a lost audio frame with a threshold value, to decide whether to input a deterministic time domain excitation signal with the addition of a noise like time domain excitation signal into an LPC synthesis, or whether to input only a noise time domain excitation signal into the LPC synthesis,
• when said computer program is run by a computer.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises acquiring a pitch information describing a pitch of the audio frame preceding the lost audio frame, and providing the error concealment audio information in dependence on the pitch information;
• wherein the pitch information is acquired on the basis of the time domain excitation signal associated with the audio frame preceding the lost audio frame,
• when said computer program is run by a computer.

A non-transitory digital storage medium having stored thereon a computer program for performing the method for providing a decoded audio information on the basis of an encoded audio information, the method comprising:

• providing an error concealment audio information for concealing a loss of an audio frame,
• wherein a time domain excitation signal acquired on the basis of one or more audio frames preceding a lost audio frame is modified in order to acquire the error concealment audio information;
• wherein the method comprises copying a pitch cycle of the time domain excitation signal associated with the audio frame preceding the lost audio frame one time or multiple times, in order to acquire an excitation signal for a synthesis of the error concealment audio information;
• wherein the method comprises low-pass filtering the pitch cycle of the time domain excitation signal associated with the audio frame preceding the lost audio frame using a sampling-rate dependent filter, a bandwidth of which is dependent on a sampling rate of the audio frame encoded in a frequency domain representation,
• when said computer program is run by a computer.