Abstract: A stereo signal encoding method includes performing spectrum broadening on a quantized line spectral frequency (LSF) parameter of a primary channel signal in a current frame in a stereo signal to obtain a spectrum-broadened LSF parameter of the primary channel signal, determining a prediction residual of an LSF parameter of a secondary channel signal in the current frame based on an original LSF parameter of the secondary channel signal and the spectrum-broadened LSF parameter of the primary channel signal, and performing a quantization on the prediction residual of the LSF parameter of the secondary channel signal.

Abstract: An encoding method includes determining an adaptive broadening factor based on a quantized line spectral frequency (LSF) vector of a first channel of a current frame of an audio signal and an LSF vector of a second channel of the current frame, and writing the quantized LSF vector and the adaptive broadening factor into a bitstream.

Abstract: A method for encoding an audio signal includes obtaining an ITD value of a current frame of an audio signal; obtaining a characteristic parameter of the current frame, wherein the characteristic parameter comprises at least one of a signal-to-noise ratio of the current frame or a peak feature of cross correlation coefficients of the current frame; determining, based on the characteristic parameter, whether to use the initial ITD value as the finalized ITD value of the current frame; and encoding the current frame based on the finalized ITD value of the current frame, wherein if the initial ITD value is determined as not used as the finalized ITD value of the current frame, the finalized ITD value of the current frame is the same as a finalized ITD value of a previous frame of the current frame.

Abstract: A thin-film bulk acoustic resonator (FBAR) apparatus includes a lower dielectric layer including a first cavity; an upper dielectric layer including a second cavity, wherein the upper dielectric layer is on the lower dielectric layer; and an acoustic resonance film that is positioned between and separating the first and the second cavities. The acoustic resonance film includes a lower electrode layer, an upper electrode layer, and a piezoelectric film that is sandwiched between the lower and upper electrode layers. A plan view of the first and the second cavities overlap to form an overlapped region having a polygonal shape without parallel sides.

Abstract: Various embodiments provide a method and an apparatus for determining a weighting factor during stereo signal encoding. In those embodiments, a parameter value corresponding to the encoding mode of the to-be-encoded signal is determining based on an encoding mode of a to-be-encoded signal in a stereo signal and a correspondence between an encoding mode and a parameter value. Based on the determined parameter value and an energy spectrum of a linear prediction filter corresponding to an original line spectral frequency parameter of the to-be-encoded signal is a weighting factor for calculating a distance between the original line spectral frequency parameter and a target original line spectral frequency parameter is calculated.

Abstract: An audio encoding and decoding method and a related apparatus are provided. The audio encoding method includes: determining a channel combination scheme for a current frame; when the channel combination scheme for the current frame is different from a channel combination scheme for a previous frame, performing segmented time-domain downmix processing on left and right channel signals in the current frame based on the channel combination scheme for the current frame and the channel combination scheme for the previous frame, to obtain a primary channel signal and a secondary channel signal in the current frame; and encoding the obtained primary channel signal and secondary channel signal in the current frame.

Abstract: A delay estimation method includes determining a cross-correlation coefficient of a multi-channel signal of a current frame, determining a delay track estimation value of the current frame based on buffered inter-channel time difference information of at least one past frame, determining an adaptive window function of the current frame, performing weighting on the cross-correlation coefficient based on the delay track estimation value of the current frame and the adaptive window function of the current frame, to obtain a weighted cross-correlation coefficient, and determining an inter-channel time difference of the current frame based on the weighted cross-correlation coefficient.

Abstract: This disclosure provides an encoding method, a decoding method, an encoding apparatus, and a decoding apparatus for a stereo signal. The encoding method includes: performing interpolation processing based on the inter-channel time difference in the current frame and an inter-channel time difference in a previous frame of the current frame; performing time-domain downmixing processing on the stereo signal after the delay alignment in the current frame, to obtain a primary-channel signal and a secondary-channel signal in the current frame; and quantizing the inter-channel time difference after the interpolation processing in the current frame, the primary channel signal and the secondary channel signal.