An audio encoder for providing an output signal using an input audio signal includes a patch generator, a comparator and an output interface. The patch generator generates at least one bandwidth extension high-frequency signal, wherein a bandwidth extension high-frequency signal includes a high-frequency band. The high-frequency band of the bandwidth extension high-frequency signal is based on a low frequency band of the input audio signal. A comparator calculates a plurality of comparison parameters. A comparison parameter is calculated based on a comparison of the input audio signal and a generated bandwidth extension high-frequency signal. Each comparison parameter of the plurality of comparison parameters is calculated based on a different offset frequency between the input audio signal and a generated bandwidth extension high-frequency signal. Further, the comparator determines a comparison parameter from the plurality of comparison parameters, wherein the determined comparison parameter fulfils a predefined criterion.

This application provides a data transmission method and apparatus. The method includes: obtaining significant bits in an N.sup.th data frame, where N is an integer greater than or equal to 1, a quantity of the significant bits in the N.sup.th data frame is smaller than a quantity of bits in the N.sup.th data frame, and remaining bits other than the significant bits in the N.sup.th data frame are insignificant bits in the N.sup.th data frame; and sending the significant bits in the N.sup.th data frame, and skipping sending the insignificant bits in the N.sup.th data frame. According to the application, on a premise of ensuring voice intelligibility, a transmit end apparatus transmits only the significant bits, to minimize a data transmission amount, thereby improving transmission reliability and coverage.

A method for decoding an encoded audio bitstream is disclosed. The method includes receiving the encoded audio bitstream and decoding the audio data to generate a decoded lowband audio signal. The method further includes extracting high frequency reconstruction metadata and filtering the decoded lowband audio signal with an analysis filterbank to generate a filtered lowband audio signal. The method also includes extracting a flag indicating whether either spectral translation or harmonic transposition is to be performed on the audio data and regenerating a highband portion of the audio signal using the filtered lowband audio signal and the high frequency reconstruction metadata in accordance with the flag.

An audio encoding method and device and an audio decoding method and device are provided. The audio encoding method includes: obtaining a current frame of an audio signal, where the current frame includes a high frequency band signal and a low frequency band signal; obtaining a compatible layer encoding parameter of the current frame based on the high frequency band signal and the low frequency band signal; obtaining an enhancement layer encoding parameter of the current frame based on the high frequency band signal; and performing bitstream multiplexing on the compatible layer encoding parameter and the enhancement layer encoding parameter to obtain an encoded bitstream.

An audio encoder for providing an output signal using an input audio signal includes a patch generator, a comparator and an output interface. The patch generator generates at least one bandwidth extension high-frequency signal, wherein a bandwidth extension high-frequency signal includes a high-frequency band. The high-frequency band of the bandwidth extension high-frequency signal is based on a low frequency band of the input audio signal. A comparator calculates a plurality of comparison parameters. A comparison parameter is calculated based on a comparison of the input audio signal and a generated bandwidth extension high-frequency signal. Each comparison parameter of the plurality of comparison parameters is calculated based on a different offset frequency between the input audio signal and a generated bandwidth extension high-frequency signal. Further, the comparator determines a comparison parameter from the plurality of comparison parameters, wherein the determined comparison parameter fulfils a predefined criterion.

An apparatus, method and computer program product for: providing spatial audio signals for output for a first user via a first audio device and a second audio device, receiving an indication of deactivation of the second audio device, receiving an indication that the second audio device is re-activated by a second user, and performing, in response to receiving the indication that the second audio device is re-activated by the second user, a modification of the spatial audio signals.

An apparatus, method and computer program product for: providing spatial audio signals for output for a first user via a first audio device and a second audio device, receiving an indication of deactivation of the second audio device, receiving an indication that the second audio device is re-activated by a second user, and performing, in response to receiving the indication that the second audio device is re-activated by the second user, a modification of the spatial audio signals.

According to the present disclosure, the method for receiving the audio data by the first device, comprises: transmitting, to a third device, a notification message requesting a change of a configuration related to audio data streaming of the first device, wherein the notification message includes configuration change information for changing the configuration related to the audio data streaming; performing, with the third device, a configuration change procedure for changing the configuration related to the audio data streaming, on the basis of the notification message; and receiving, from the third device, audio data related to the audio data streaming, on the basis of the changed configuration related to the audio data streaming, wherein the configuration change procedure is initiated on the basis of the notification message, and the configuration related to the audio data streaming is changed on the basis of the configuration change information.

According to the present disclosure, the method for receiving the audio data by the first device, comprises: transmitting, to a third device, a notification message requesting a change of a configuration related to audio data streaming of the first device, wherein the notification message includes configuration change information for changing the configuration related to the audio data streaming; performing, with the third device, a configuration change procedure for changing the configuration related to the audio data streaming, on the basis of the notification message; and receiving, from the third device, audio data related to the audio data streaming, on the basis of the changed configuration related to the audio data streaming, wherein the configuration change procedure is initiated on the basis of the notification message, and the configuration related to the audio data streaming is changed on the basis of the configuration change information.

A sound signal downmix method includes an inter-channel relationship information obtaining step of obtaining an inter-channel correlation value and an inter-channel time difference in an approximate manner, and a downmix step of obtaining a downmix signal based on the obtained information. In the inter-channel relationship information obtaining step, multiple channel signals are sorted such that signals of adjacent channels are similar to each other, the inter-channel correlation value and the inter-channel time difference are determined only between adjacent channels after the sorting, the inter-channel correlation value between non-adjacent channels is obtained by a product or a geometric mean of the inter-channel correlations between the adjacent channels, and the inter-channel time difference between non-adjacent channels is obtained by adding up the inter-channel time differences of adjacent channels.