An apparatus comprising means configured to obtain direction parameter values (108) associated with at least two time-frequency parts (202) of at least one audio signal (102); and encode the obtained direction parameter values based on a codebook (206), wherein the codebook comprises two or more quantization levels arranged such that a first quantization level comprises a first set of quantization values, and a second or succeeding quantization level comprises a second or further set of quantization values and preceding quantization level quantization values.

An apparatus comprising means configured to obtain direction parameter values (108) associated with at least two time-frequency parts (202) of at least one audio signal (102); and encode the obtained direction parameter values based on a codebook (206), wherein the codebook comprises two or more quantization levels arranged such that a first quantization level comprises a first set of quantization values, and a second or succeeding quantization level comprises a second or further set of quantization values and preceding quantization level quantization values.

A signal processing method and device includes obtaining spectral coefficients of a current frame of an audio signal, in which N sub-bands of the current frame comprises at least one of the spectral coefficients. A total energy of M successive sub-bands of the N sub-bands, a total energy of K successive sub-bands of the N sub-bands, and an energy of a first sub-band are obtained to determine whether to modify original envelope values of the M sub-bands. When the original envelope values of the M sub-bands are modified, encoding bits are allocated to each of the N sub-bands according to the modified envelope values of the M sub-bands.

A signal processing method and device includes obtaining spectral coefficients of a current frame of an audio signal, in which N sub-bands of the current frame comprises at least one of the spectral coefficients. A total energy of M successive sub-bands of the N sub-bands, a total energy of K successive sub-bands of the N sub-bands, and an energy of a first sub-band are obtained to determine whether to modify original envelope values of the M sub-bands. When the original envelope values of the M sub-bands are modified, encoding bits are allocated to each of the N sub-bands according to the modified envelope values of the M sub-bands.

According to an aspect of the present invention, a method for reconstructing an audio signal having a baseband portion and a highband portion is disclosed. The method includes obtaining a decoded baseband audio signal by decoding an encoded audio signal and obtaining a plurality of subband signals by filtering the decoded baseband audio signal. The method further includes generating a high-frequency reconstructed signal by copying a number of consecutive subband signals of the plurality of subband signals and obtaining an envelope adjusted high-frequency signal. The method further includes generating a noise component based on a noise parameter. Finally, the method includes adjusting a phase of the high-frequency reconstructed signal and obtaining a time-domain reconstructed audio signal by combining the decoded baseband audio signal and the combined high-frequency signal to obtain a time-domain reconstructed audio signal.

A bit allocating method is provided that includes determining the allocated number of bits in decimal point units based on each frequency band so that a Signal-to-Noise Ratio (SNR) of a spectrum existing in a predetermined frequency band is maximized within a range of the allowable number of bits for a given frame; and adjusting the allocated number of bits based on each frequency band.

A bit allocating method is provided that includes determining the allocated number of bits in decimal point units based on each frequency band so that a Signal-to-Noise Ratio (SNR) of a spectrum existing in a predetermined frequency band is maximized within a range of the allowable number of bits for a given frame; and adjusting the allocated number of bits based on each frequency band.

Aspects of the disclosure include methods, apparatuses, and non-transitory computer-readable storage mediums for decoding audio data of an audio scene. One apparatus includes processing circuitry that receives first audio source data and second audio source data. The first audio source data corresponds to a space of interest in the audio scene and the second audio source data does not correspond to the space of interest in the audio scene. The space of interest in the audio scene is represented by at least one of a listener space, an audio channel, or an audio object. The processing circuitry decodes the first audio source data based on the space of interest.

Aspects of the disclosure include methods, apparatuses, and non-transitory computer-readable storage mediums for decoding audio data of an audio scene. One apparatus includes processing circuitry that receives first audio source data and second audio source data. The first audio source data corresponds to a space of interest in the audio scene and the second audio source data does not correspond to the space of interest in the audio scene. The space of interest in the audio scene is represented by at least one of a listener space, an audio channel, or an audio object. The processing circuitry decodes the first audio source data based on the space of interest.

A signal processing method and device includes obtaining spectral coefficients of a current frame of an audio signal, in which N sub-bands of the current frame comprises at least one of the spectral coefficients. A total energy of M successive sub-bands of the N sub-bands, a total energy of K successive sub-bands of the N sub-bands, and an energy of a first sub-band are obtained to determine whether to modify original envelope values of the M sub-bands. When the original envelope values of the M sub-bands are modified, encoding bits are allocated to each of the N sub-bands according to the modified envelope values of the M sub-bands.