Encoder, decoder, encoding method and decoding method for frequency domain long-term prediction of tonal signals for audio coding

A decoder for reconstructing a current frame of an audio signal, wherein one or more previous frames of the audio signal precedes the current frame, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal, wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,

• wherein the decoder is to receive an encoding of the current frame,
• wherein the decoder is to determine an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames, wherein the two harmonic parameters for each of the one or more harmonic components of the most previous frame depend on a first group of three or more of the plurality of reconstructed spectral coefficients for each of the one or more previous frames of the audio signal,
• wherein the decoder is to reconstruct the current frame depending on the encoding of the current frame and depending on the estimation of the two harmonic parameters for each of the one or more harmonic components of the most previous frame.

An apparatus for frame loss concealment, wherein one or more previous frames of the audio signal precedes a current frame of the audio signal, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal, wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,

• wherein the apparatus is to determine an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames, wherein the two harmonic parameters for each of the one or more harmonic components of the most previous frame depend on a first group of three or more of the plurality of reconstructed spectral coefficients for each of the one or more previous frames of the audio signal,
• wherein, if the apparatus does not receive the current frame, or if the current frame is received by the apparatus in a corrupted state, the apparatus is to reconstruct the current frame depending on the estimation of the two harmonic parameters for each of the one or more harmonic components of the most previous frame.

A method for encoding a current frame of an audio signal depending on one or more previous frames of the audio signal, wherein the one or more previous frames precede the current frame, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal,

• wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,
• wherein, to generate an encoding of the current frame, the method comprises determining an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames,
• wherein determining the estimation of the two harmonic parameters for each of the one or more harmonic components of the most previous frame is conducted using a first group of three or more of the plurality of spectral coefficients of each of the one or more previous frames of the audio signal.

A method for reconstructing a current frame of an audio signal, wherein one or more previous frames of the audio signal precede the current frame, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal, wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,

• wherein the method comprises receiving an encoding of the current frame,
• wherein the method comprises determining an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames, wherein the two harmonic parameters for each of the one or more harmonic components of the most previous frame depend on a first group of three or more of the plurality of reconstructed spectral coefficients for each of the one or more previous frames of the audio signal,
• wherein the method comprises reconstructing the current frame depending on the encoding of the current frame and depending on the estimation of the two harmonic parameters for each of the one or more harmonic components of the most previous frame.

A method for frame loss concealment, wherein one or more previous frames of the audio signal precedes a current frame of the audio signal, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal, wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,

• wherein the method comprises determining an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames, wherein the two harmonic parameters for each of the one or more harmonic components of the most previous frame depend on a first group of three or more of the plurality of reconstructed spectral coefficients for each of the one or more previous frames of the audio signal,
• wherein the method comprises, if the current frame is not received, or if the current frame is received by in a corrupted state, reconstructing the current frame depending on the two harmonic parameters for each of the one or more harmonic components of the most previous frame.

A non-transitory digital storage medium having stored thereon a computer program for performing a method for encoding a current frame of an audio signal depending on one or more previous frames of the audio signal, wherein the one or more previous frames precede the current frame, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal, wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,

• wherein, to generate an encoding of the current frame, the method comprises determining an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames,
• wherein determining the estimation of the two harmonic parameters for each of the one or more harmonic components of the most previous frame is conducted using a first group of three or more of the plurality of spectral coefficients of each of the one or more previous frames of the audio signal,
• 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 for frame loss concealment, wherein one or more previous frames of the audio signal precedes a current frame of the audio signal, wherein each of the current frame and the one or more previous frames comprises one or more harmonic components of the audio signal, wherein each of the current frame and the one or more previous frames comprises a plurality of spectral coefficients in a frequency domain or in a transform domain,

• wherein the method comprises determining an estimation of two harmonic parameters for each of the one or more harmonic components of a most previous frame of the one or more previous frames, wherein the two harmonic parameters for each of the one or more harmonic components of the most previous frame depend on a first group of three or more of the plurality of reconstructed spectral coefficients for each of the one or more previous frames of the audio signal,
• wherein the method comprises, if the current frame is not received, or if the current frame is received by in a corrupted state, reconstructing the current frame depending on the two harmonic parameters for each of the one or more harmonic components of the most previous frame,
• when said computer program is run by a computer.