Multi-channel signal encoding method, multi-channel signal decoding method, encoder, and decoder

A computer program product comprising instructions that are stored on a non-transitory computer-readable medium and that, when executed by a processor, cause an encoder to:

• obtain a current frame of a multi-channel signal, wherein the current frame includes a first channel signal and a second channel signal;
• obtain a downmixed signal of the current frame based on the first channel signal and the second channel signal;
• obtain an initial reverberation gain parameter of the current frame, wherein the initial reverberation gain parameter corresponds to both of the first channel signal and the second channel signal;
• obtain, based on a first correlation between the first channel signal and the downmixed signal and a second correlation between the second channel signal and the downmixed signal, a value of an identification flag that indicates that the initial reverberation gain parameter of one of the first channel signal or the second channel signal needs to be adjusted;
• quantize, based on the downmixed signal, the initial reverberation gain parameter, and the identification flag, the first channel signal and the second channel signal to obtain a quantized first channel signal and a quantized second channel signal;
• and
• write the quantized first channel signal and the quantized second channel signal into a bitstream.

An encoder, comprising:

• at least one processor;
• and
• one or more memories coupled to the at least one processor and configured to store programming instructions, that when executed by the at least one processor, cause the encoder to:
• obtain a current frame of a multi-channel signal, wherein the current frame includes a first channel signal and a second channel signal;
• obtain a downmixed signal of the current frame based on the first channel signal and the second channel signal;
• obtain an initial reverberation gain parameter of the current frame, wherein the initial reverberation gain parameter corresponds to both of the first channel signal and the second channel signal;
• obtain, based on a first correlation between the first channel signal and the downmixed signal and a second correlation between the second channel signal and the downmixed signal, a value of an identification flag that indicates that the initial reverberation gain parameter of one of the first channel signal or the second channel signal needs to be adjusted;
• quantize, based on the downmixed signal, the initial reverberation gain parameter, and the identification flag, the first channel signal and the second channel signal to obtain a quantized first channel signal and a quantized second channel signal;
• and
• write the quantized first channel signal and the quantized second channel signal into a bitstream.