Encoding method, decoding method, encoding apparatus, and decoding apparatus

A decoding method for decoding a speech signal, comprising:

• obtaining a low frequency encoding parameter, a linear predictive coding (LPC) parameter, and a high frequency gain from encoded information corresponding to the speech signal;
• obtaining a low band signal of the speech signal according to the low frequency encoding parameter;
• obtaining an excitation signal according to the low frequency encoding parameter;
• obtaining a synthesized high band signal according to the excitation signal and the LPC parameter;
• performing filtering processing on the synthesized high band signal using a pole-zero filter, wherein a coefficient of the pole-zero filter is set based on the LPC parameter, to obtain a short-time filtered signal;
• adjusting the short-time filtered signal using the high frequency gain to obtain a high band signal;
• and
• combining the low band signal of the speech signal and the high band signal to obtain a decoded signal.

An encoding apparatus for encoding a speech signal, comprising:

• a memory comprising instructions;
• and
• at least a processor coupled to the memory, the instructions causing the at least processor to be configured to:
• obtain a low band signal of the speech signal and a high band signal of the speech signal;
• encode the low band signal to obtain a low frequency encoding parameter;
• encode the high band signal to obtain a linear predictive coding (LPC) parameter;
• obtain an excitation signal according to the low frequency encoding parameter;
• obtain a synthesized high band signal according to the excitation signal and the LPC parameter;
• and
• perform filtering processing on the synthesized high band signal using a pole-zero filter, wherein a coefficient of the pole-zero filter is set based on the LPC parameter.

A decoding apparatus for decoding a speech signal, comprising:

• a memory comprising instructions;
• and
• at least one processor coupled to the memory, the instructions causing the at least one processor to be configured to:
• obtain a low frequency encoding parameter, a linear predictive coding (LPC) parameter, and a high frequency gain from encoded information corresponding to the speech signal;
• obtain a low band signal of the speech signal according to the low frequency encoding parameter;
• obtain an excitation signal according to the low frequency encoding parameter;
• obtain a synthesized high band signal according to the excitation signal and the LPC parameter;
• perform filtering processing on the synthesized high band signal using a pole-zero filter, wherein a coefficient of the pole-zero filter is set based on the LPC parameter, to obtain a short-time filtered signal;
• adjust the short-time filtered signal using the high frequency gain to obtain a high band signal;
• and
• combine the low band signal of the speech signal and the high band signal to obtain a decoded signal.