Audio decoder, audio encoder and method for coding of frames using a quantization noise shaping

Audio decoder configured to, for a predetermined frame among consecutive frames,

• decode, from a data stream,
• a quantized spectrum;
• a linear prediction coefficient based spectral envelope representation,
• locate, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• derive a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data spectrally shaped using a first spectral shaping function which depends, according to a first manner, on the linear prediction coefficient based spectral envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• spectrally shaping the quantized spectrum using a second spectral shaping function which depends, in a second manner, on the linear prediction coefficient based spectral envelope representation,
• reconstruct the predetermined frame using the dequantized spectrum,
• wherein the audio decoder is configured so that the first spectral shaping function is different from, e.g. less smooth than, the second spectral shaping function.

Audio decoder configured to, for a predetermined frame among consecutive frames,

• decode, from a data stream,
• a quantized spectrum;
• a linear prediction coefficient based temporal envelope representation,
• locate, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• derive a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data filtered using a first filter which depends, according to a first manner, on the linear prediction coefficient based temporal envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• filtering the quantized spectrum using a second filter which depends, in a second manner, on the linear prediction coefficient based temporal envelope representation,
• reconstruct the predetermined frame using the dequantized spectrum,
• wherein the audio decoder is configured so that a transfer function of the first filter is different from, e.g. less smooth than, a transfer function of the second filter.

Audio encoder configured to, for a predetermined frame among consecutive frames,

• encode, into a data stream,
• a quantized spectrum;
• a linear prediction coefficient based envelope representation,
• locate, in the quantized spectrum, zero-quantized portions and non-zero-quantized portions,
• derive a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data modified depending, according to a first manner, on the linear prediction coefficient based envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• modifying the quantized spectrum depending, in a second manner, on the linear prediction coefficient based envelope representation,
• use the dequantized spectrum for encoding further frames,
• wherein the audio encoder is configured so that, for a predetermined portion,
• the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation and the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation
• cause a spectral quantization noise shaping which is different for the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation than for the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation, and/or
• cause a temporal quantization noise shaping which is different for the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation than for the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation.

Audio encoder configured to, for a predetermined frame among consecutive frames,

• encode, into a data stream,
• a quantized spectrum;
• a linear prediction coefficient based spectral envelope representation,
• locate, in the quantized spectrum, zero-quantized portions and non-zero-quantized portions,
• derive a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data spectrally shaped using a first spectral shaping function which depends, according to a first manner, on the linear prediction coefficient based spectral envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• spectrally shaping the quantized spectrum using a second spectral shaping function which depends, in a second manner, on the linear prediction coefficient based spectral envelope representation,
• use the dequantized spectrum for encoding further frames,
• wherein the audio encoder is configured so that the first spectral shaping function is less smooth than the second spectral shaping function.

Audio encoder configured to, for a predetermined frame among consecutive frames,

• encode, into a data stream,
• a quantized spectrum;
• a linear prediction coefficient based temporal envelope representation,
• locate, in the quantized spectrum, zero-quantized portions and non-zero-quantized portions,
• derive a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data filtered using a first filter which depends, according to a first manner, on the linear prediction coefficient based temporal envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• filtering the quantized spectrum using a second filter which depends, in a second manner, on the linear prediction coefficient based temporal envelope representation,
• use the dequantized spectrum for encoding further frames,
• wherein the audio encoder is configured so that a transfer function of the first filter is less smooth than a transfer function of the second filter.

Method for a predetermined frame among consecutive frames, wherein the method comprises:

• decoding, from a data stream,
• a quantized spectrum, and
• a linear prediction coefficient based envelope representation;
• locating, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• deriving a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data modified depending, according to a first manner, on the linear prediction coefficient based envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• modifying the quantized spectrum depending, in a second manner, on the linear prediction coefficient based envelope representation,
• reconstructing the predetermined frame using the dequantized spectrum,
• wherein the method is performed so that, for a predetermined portion, the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation and the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation
• cause a spectral quantization noise shaping which is different, e.g. less smooth, for the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation than for the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation, and/or
• cause a temporal quantization noise shaping which is different, e.g. less smooth, for the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation than for the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation.

Method for a predetermined frame among consecutive frames, wherein the method comprises:

• decoding, from a data stream,
• a quantized spectrum,
• a linear prediction coefficient based spectral envelope representation;
• locating, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• deriving a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data spectrally shaped using a first spectral shaping function which depends, according to a first manner, on the linear prediction coefficient based spectral envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• spectrally shaping the quantized spectrum using a second spectral shaping function which depends, in a second manner, on the linear prediction coefficient based spectral envelope representation;
• reconstructing the predetermined frame using the dequantized spectrum;
• wherein the first spectral shaping function is different from, e.g. less smooth than, the second spectral shaping function.

Method for a predetermined frame among consecutive frames, wherein the method comprises:

• decoding, from a data stream,
• a quantized spectrum and
• a linear prediction coefficient based temporal envelope representation;
• locating, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• deriving a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data filtered using a first filter which depends, according to a first manner, on the linear prediction coefficient based temporal envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• filtering the quantized spectrum using a second filter which depends, in a second manner, on the linear prediction coefficient based temporal envelope representation;
• reconstructing the predetermined frame using the dequantized spectrum;
• wherein a transfer function of the first filter different from, e.g. is less smooth than, a transfer function of the second filter.

Method for a predetermined frame among consecutive frames, wherein the method comprises:

• encoding, into a data stream,
• a quantized spectrum and
• a linear prediction coefficient based envelope representation;
• locating, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• deriving a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data modified depending, according to a first manner, on the linear prediction coefficient based envelope representation, and
• in non-zero-quantized portions of the quantized spectrum
• modifying the quantized spectrum depending, in a second manner, on the linear prediction coefficient based envelope representation;
• using the dequantized spectrum for encoding further frames,
• wherein the method is performed so that, for a predetermined portion, the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation and the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation
• cause a spectral quantization noise shaping which is different, e.g. less smooth, for the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation than for the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation, and/or
• cause a temporal quantization noise shaping which is different, e.g. less smooth, for the modification which is used in case of predetermined portion being a zero-quantized portion, and depends, according to the first manner, on the linear prediction coefficient based envelope representation than for the modification which is used in case of predetermined portion being a non-zero-quantized portion, and depends, according to the second manner, on the linear prediction coefficient based envelope representation.

Method for a predetermined frame among consecutive frames, wherein the method comprises:

• encoding, into a data stream,
• a quantized spectrum, and
• a linear prediction coefficient based spectral envelope representation;
• locating, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• deriving a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data spectrally shaped using a first spectral shaping function which depends, according to a first manner, on the linear prediction coefficient based spectral envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• spectrally shaping the quantized spectrum using a second spectral shaping function which depends, in a second manner, on the linear prediction coefficient based spectral envelope representation;
• using the dequantized spectrum for encoding further frames;
• wherein the first spectral shaping function is different from, e.g. less smooth than, the second spectral shaping function.

Method for a predetermined frame among consecutive frames, wherein the method comprises:

• encoding, into a data stream,
• a quantized spectrum and
• a linear prediction coefficient based temporal envelope representation;
• locating, in the quantized spectrum, one or more zero-quantized portions and one or more non-zero-quantized portions,
• deriving a dequantized spectrum using
• in zero-quantized portions of the quantized spectrum,
• filling the quantized spectrum with a synthesized spectral data filtered using a first filter which depends, according to a first manner, on the linear prediction coefficient based temporal envelope representation, and
• in non-zero-quantized portions of the quantized spectrum,
• filtering the quantized spectrum using a second filter which depends, in a second manner, on the linear prediction coefficient based temporal envelope representation;
• using the dequantized spectrum for encoding further frames;
• wherein a transfer function of the first filter is different from, e.g. less smooth than, a transfer function of the second filter.