Patent ID: 11961526
Assignee: HUAWEI TECHNOLOGIES CO., LTD.
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G

Claim 11:
12. An apparatus for calculating a downmixed signal and a residual signal, the apparatus comprising:
a processor; and
a memory configured to store a program, which
when executed by the processor, cause to the processor to:
obtain an audio signal including a plurality of frames;
obtain an initial downmixed signal and an initial residual signal of a subband corresponding to a preset frequency band in a current frame of the audio signal;
determine whether a first target frame of the audio signal is a switching frame, wherein the first target frame is the current frame or a previous frame of the current frame;
if the first target frame is a switching frame, calculate, based on a switch fade-in/fade-out factor of a second target frame, the initial downmixed signal, and the initial residual signal, a to-be-encoded downmixed signal and a to-be-encoded residual signal of the subband corresponding to the preset frequency band in the current frame; and
encode the to-be-encoded downmixed signal and the to-be-encoded residual signal to obtain an encoded bitstream;
wherein the second target frame is the current frame or the previous frame of the current frame, and the fade-in/fade-out factor is determined based on a residual signal coding parameter of the second target frame and at least one of an inter-frame energy fluctuation parameter or an inter-frame amplitude fluctuation parameter of the second target frame, and
wherein the residual signal coding parameter represents an energy relationship between a first downmixed signal and a first residual signal of the second target frame, and the inter-frame energy fluctuation parameter or the inter-frame amplitude fluctuation parameter represents an energy or amplitude relationship between a signal of the second target frame and signals of M frames previous to the second target frame, wherein M is a positive integer.