Audio signal coding method, and device for carrying out same

A method of encoding an audio signal, the method comprising:

• generating a first frequency spectrum corresponding to an input audio signal;
• generating complex linear prediction coefficients (LPCs) corresponding to the first frequency spectrum;
• obtaining complex spectrum frequency information based on a first complex polynomial, which is a complex spectrum polynomial using the complex LPCs as a coefficient;
• and
• generating a bitstream including information obtained by quantizing the first frequency spectrum and the complex spectrum frequency information.

A device for decoding an audio signal, the device comprising:

• a processor;
• and
• a memory configured to store instructions,
• wherein, the instructions when executed by the processor, cause the device to perform a plurality of operations, and
• the plurality of operations comprises:
• receiving a bitstream comprising information about a first audio signal;
• and
• generating a second audio signal based on first quantization information and a first frequency spectrum obtained from the bitstream,
• wherein the first quantization information comprises
• quantized complex spectrum frequency information corresponding to the first audio signal, and
• the generating of the second audio signal comprises:
• obtaining a first complex polynomial, which is a complex spectrum polynomial, based on the quantized complex spectrum frequency information,
• restoring complex linear prediction coefficients (LPCs) corresponding to the first audio signal by extracting a coefficient from the first complex polynomial, and
• generating the second audio signal based on the first frequency spectrum and restored complex LPCs.

A device for encoding an audio signal, the device comprising:

• a processor;
• and
• a memory configured to store instructions,
• wherein the instructions, when executed by the processor, cause the device to perform a plurality of operations, and
• the plurality of operations comprises:
• generating a first frequency spectrum corresponding to an input audio signal;
• generating complex linear prediction coefficients (LPCs) corresponding to the first frequency spectrum;
• obtaining complex spectrum frequency information based on a first complex polynomial, which is a complex spectrum polynomial using the complex LPCs as a coefficient;
• and
• generating a bitstream including information obtained by quantizing the first frequency spectrum and the complex spectrum frequency information.