Encoder, decoder and method for encoding and decoding audio content using parameters for enhancing a concealment

An apparatus for decoding audio content using at least a TCX (Transform Coded Excitation) coding scheme, wherein the apparatus is configured to

• receive a primary encoded representation of a current frame and/or an encoded representation of at least one error concealment helper parameter for providing a decoder-sided guided error concealment of the current frame, wherein the encoded representation of the at least one error concealment helper parameter is transmitted in-band as part of the codec payload,
• wherein the apparatus is configured to extract the error concealment helper parameter of a current frame from a packet that is separated from a packet in which the primary encoded representation of the current frame is comprised,
• wherein the apparatus is configured to use the guided error concealment for at least partly reconstructing the audio content of the current frame by using the at least one error concealment helper parameter in case the primary encoded representation of the current frame is lost, corrupted or delayed,
• wherein the apparatus is configured to selectively choose between at least two error concealment modes which use different encoded representations of the at least one error concealment helper parameters for at least partially reconstructing the audio content using the guided error concealment,
• wherein one of the at least two error concealment modes, which uses different encoded representations of the at least one error concealment parameters, is a time domain concealment mode that is selected if the audio content comprised in the current frame comprises a transient or if the global gain of the audio content comprised in the current frame is lower than the global gain of the preceding frame,
• and wherein a further one of the at least two error concealment modes, which uses different encoded representations of the at least one error concealment helper parameters, is a frequency domain concealment mode wherein the encoded representation of the at least one error concealment helper parameter comprises one or more of an LSF (Line Spectral Frequency) parameter, a TCX global gain and a classifier information,
• wherein the apparatus is implemented, at least in part, by one or more hardware elements.

A method for encoding audio content using a TCX (Transform Coded Excitation) coding scheme, the method comprising:

• providing a primary encoded representation of a current frame and an encoded representation of at least one error concealment helper parameter, said error concealment helper parameter for providing a decoder-sided guided error concealment of the current frame, and transmitting the encoded representation of the at least one error concealment helper parameter in-band as part of the codec payload, wherein
• selecting the at least one error concealment helper parameter based on one or more parameters representing a signal characteristic of the audio content comprised in the current frame,
• and selectively choosing between at least two modes for providing an encoded representation of the at least one error concealment helper parameter,
• wherein one of the at least two modes for providing an encoded representation of the at least one error concealment helper parameter is a time domain concealment mode that is selected if the audio content comprised in the current frame comprises a transient or if the global gain of the audio content comprised in the current frame is lower than the global gain of the preceding frame,
• and wherein a further one of the at least two modes for providing an encoded representation of the at least one error concealment helper parameter is a frequency domain concealment mode such that the encoded representation of the at least one error concealment parameter comprises one or more of an LSF parameter, a TCX global gain and a classifier information.

A method for decoding audio content using a TCX (Transform Coded Excitation) coding scheme, the method comprising:

• receiving a primary encoded representation of a current frame and/or an encoded representation of at least one error concealment helper parameter, said error concealment helper parameter for providing a decoder-sided guided error concealment of the current frame, wherein the encoded representation of the at least one error concealment helper parameter is transmitted in-band as part of the codec payload,
• using, at the decoder-side, the guided error concealment for at least partly reconstructing the audio content of the current frame by using the at least one error concealment helper parameter in case the primary encoded representation of the current frame is lost, corrupted or delayed,
• selectively choosing between at least two error concealment modes which use different encoded representations of the at least one error concealment helper parameters for at least partially reconstructing the audio content using the guided error concealment,
• wherein one of the at least two error concealment modes, which uses different encoded representations of the at least one error concealment parameters, is a time domain concealment mode that is selected if the audio content comprised in the current frame comprises a transient or if the global gain of the audio content comprised in the current frame is lower than the global gain of the preceding frame,
• and wherein a further one of the at least two error concealment modes, which uses different encoded representations of the at least one error concealment helper parameters, is a frequency domain concealment mode wherein the encoded representation of the at least one error concealment helper parameter comprises one or more of an LSF parameter, a TCX global gain and a classifier information.

A non-transitory digital storage medium having stored thereon a computer program for performing a method of encoding audio content using a TCX (Transform Coded Excitation) coding scheme, the method comprising:

• providing a primary encoded representation of a current frame and an encoded representation of at least one error concealment helper parameter, said error concealment helper parameter for providing a decoder-sided guided error concealment of the current frame, and transmitting the encoded representation of the at least one error concealment helper parameter in-band as part of the codec payload, wherein
• selecting the at least one error concealment helper parameter based on one or more parameters representing a signal characteristic of the audio content comprised in the current frame,
• and selectively choosing between at least two modes for providing an encoded representation of the at least one error concealment helper parameter,
• wherein one of the at least two modes for providing an encoded representation of the at least one error concealment helper parameter is a time domain concealment mode that is selected if the audio content comprised in the current frame comprises a transient or if the global gain of the audio content comprised in the current frame is lower than the global gain of the preceding frame,
• and wherein a further one of the at least two modes for providing an encoded representation of the at least one error concealment helper parameter is a frequency domain concealment mode such that the encoded representation of the at least one error concealment parameter comprises one or more of an LSF parameter, a TCX global gain and a classifier information,
• when said computer program is run by a computer.

A non-transitory digital storage medium having stored thereon a computer program for performing a method of decoding audio content using a TCX (Transform Coded Excitation) coding scheme, the method comprising:

• receiving a primary encoded representation of a current frame and/or an encoded representation of at least one error concealment helper parameter, said error concealment helper parameter for providing a decoder-sided guided error concealment of the current frame, wherein the encoded representation of the at least one error concealment helper parameter is transmitted in-band as part of the codec payload,
• using, at the decoder-side, the guided error concealment for at least partly reconstructing the audio content of the current frame by using the at least one error concealment helper parameter in case the primary encoded representation of the current frame is lost, corrupted or delayed,
• selectively choosing between at least two error concealment modes which use different encoded representations of the at least one error concealment helper parameters for at least partially reconstructing the audio content using the guided error concealment,
• wherein one of the at least two error concealment modes, which uses different encoded representations of the at least one error concealment parameters, is a time domain concealment mode that is selected if the audio content comprised in the current frame comprises a transient or if the global gain of the audio content comprised in the current frame is lower than the global gain of the preceding frame,
• and wherein a further one of the at least two error concealment modes, which uses different encoded representations of the at least one error concealment helper parameters, is a frequency domain concealment mode wherein the encoded representation of the at least one error concealment helper parameter comprises one or more of an LSF parameter, a TCX global gain and a classifier information,
• when said computer program is run by a computer.