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US 9,792,257 B2Granted
Audio signal processing method and encoder
AssigneeHuawei Technologies Co., Ltd.
InventorsDeming Zhang, Haiting Li, Anisse Taleb, Jianfeng Xu
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Abstract
An embodiment of the present invention discloses a data processing method, including: twiddling input data, so as to obtain twiddled data; pre-rotating the twiddled data by using a symmetric rotate factor, where the rotate factor is a·W4L2p+1, p=0, . . . , L/2−1, and a is a constant; performing a Fast Fourier (Fast Fourier Transform, FFT) transform of L/2 point on the pre-rotated data, where L is the length of the input data; post-rotating the data that has undergone the FFT transform by using a symmetric rotate factor, where the rotate factor is b·W4L2q+1, q=0, . . . , L/2−1, and b is a constant; and obtaining output data.
Claims26
A method for processing an audio signal, the method comprising:
- obtaining, by an encoder comprising a processor, a windowed time domain data by windowing an input audio signal;
- obtaining, by the encoder, a twiddled signal based on the windowed time domain data;
- pre-rotating, by the encoder, the twiddled signal by using a first symmetric rotation factor to obtain a pre-rotated data, wherein the first symmetric rotation factor is a·W4L2p+1, p=0, . . . , L/2−1, wherein a is a constant, wherein L is the length of the input audio signal;
- performing, by the encoder, a Fast Fourier transform (FFT) of L/2 points on the pre-rotated data to obtain FFT data;
- performing, by the encoder, an in-place fixed rotate compensation on the FFT data;
- post-rotating, by the encoder, the data that has undergone the in-place fixed rotate compensation by using a second symmetric rotation factor to obtain a post-rotated data, wherein the second symmetric rotation factor is b·W4L2p+1, q=L/2−1, and b is a constant;
- quantizing, by the encoder, a signal derived from the post-rotated data to obtain a quantized signal;
- and
- writing, by the encoder, the quantized signal into a bitstream for transmitting or storing.
6 more elements
An encoder for processing an audio signal, the encoder comprising:
- a memory for storing processor-executable instructions;
- and
- a processor operatively coupled to the memory, the processor being configured to execute the processor-executable instructions to cause the encoder to:
- obtain a windowed time domain data by windowing an input audio signal,
- obtain a twiddled signal based on the windowed time domain data;
- pre-rotate the twiddled signal by using a first symmetric rotation factor to obtain a pre-rotated data, wherein the first symmetric rotation factor is a·W4L2p+1, p=0, . . . , L/2−1, wherein a is a constant, wherein L is the length of the input audio signal,
- perform a Fast Fourier transform (FFT) of L/2 points on the pre-rotated data to obtain FFT data,
- perform an in-place fixed rotate compensation on the FFT data,
- post-rotate the data that has undergone the in-place fixed rotate compensation by using a second symmetric rotate factor to obtain a post-rotated data, wherein the second symmetric rotation factor is b·W4L2q+1, q=0, . . . , L/2−1, and b is a constant,
- quantize a signal derived from the post-rotated data to obtain a quantized signal, and
- write the quantized signal into a bitstream for transmitting or storing.
8 more elements
A method for processing an audio signal, the method comprising:
- obtaining, by an encoder comprising a processor, a windowed time domain data by windowing an input audio signal;
- obtaining, by the encoder, a twiddled signal based on the windowed time domain data;
- pre-rotating, by the encoder, the twiddled signal by using a first symmetric rotation factor to obtain a pre-rotated data, wherein the first symmetric rotation factor is a·W4L2p+1, p=0, . . . , L/2−1, wherein a is a constant, wherein L is the length of the input audio signal;
- performing, by the encoder, a Fast Fourier transform (FFT) of L/2 points on the pre-rotated data to obtain FFT data;
- performing, by the encoder, an in-place fixed rotate compensation on the FFT data;
- post-rotating, by the encoder, the data that has undergone the in-place fixed rotate compensation by using a second symmetric rotation factor to obtain a post-rotated data, wherein the second symmetric rotation factor is b·W4L2q+1, q=0, . . . , L/2−1, and b is a constant;
- obtaining, by the encoder, a frequency domain data based on the post-rotated data;
- quantizing, by the encoder, a signal derived from the frequency domain data to obtain a quantized signal;
- and
- writing, by the encoder, the quantized signal into a bitstream for transmitting or storing.
7 more elements
An encoder for processing an audio signal, the encoder comprising:
- a memory for storing processor-executable instructions;
- and
- a processor operatively coupled to the memory, the processor being configured to execute the processor-executable instructions to cause the encoder to:
- obtain a windowed time domain data by windowing an input audio signal,
- obtain a twiddled signal based on the windowed time domain data,
- pre-rotate the twiddled signal by using a first symmetric rotation factor to obtain a pre-rotated data, wherein the first symmetric rotation factor is a·W4L2q+1, p=0, . . . , L/2−1, wherein a is a constant, wherein L is the length of the input audio signal,
- perform a Fast Fourier transform (FFT) of L/2 points on the pre-rotated data to obtain FFT data,
- perform an in-place fixed rotate compensation on the FFT data,
- post-rotate the data that has undergone the in-place fixed rotate compensation by using a second symmetric rotation factor to obtain a post-rotated data, wherein the second symmetric rotation factor is b·W4L2q+1, q=0, . . . , L/2−1, and b is a constant,
- obtain a frequency domain data based on the post-rotated data,
- quantize a signal derived from the frequency domain data to obtain a quantized signal, and
- write the quantized signal into a bitstream for transmitting or storing.
9 more elements
Dependencies are inferred from the claim text.