Method for Encoding Multi-Channel Signal and Encoder

Patent metadata

Field	Value
Publication number	US-2025037726-A1
Application number	US-202418917486-A
Country	US
Kind code	A1
Filing date	Oct 16, 2024
Priority date	Aug 10, 2016
Publication date	Jan 30, 2025
Grant date	—

Abstract

A method for encoding an audio signal includes obtaining an ITD value of a current frame of an audio signal; obtaining a characteristic parameter of the current frame, wherein the characteristic parameter comprises at least one of a signal-to-noise ratio of the current frame or a peak feature of cross correlation coefficients of the current frame; determining, based on the characteristic parameter, whether to use the initial ITD value as the finalized ITD value of the current frame; and encoding the current frame based on the finalized ITD value of the current frame, wherein if the initial ITD value is determined as not used as the finalized ITD value of the current frame, the finalized ITD value of the current frame is the same as a finalized ITD value of a previous frame of the current frame.

First claim

1 . A method for encoding an audio signal, the method comprising:
obtaining a signal-to-noise ratio of a current frame; determining whether the signal-to-noise ratio meets one of a plurality of preset conditions; adjusting, in response to determining that the signal-to-noise ratio meets the one of the preset conditions, a frame count to obtain an adjusted frame count; determining, based on the adjusted frame count, whether to use a previous inter-channel time difference (ITD) value of a previous frame of the current frame as a current ITD value of the current frame; encoding, in response to determining to use the previous ITD value as the current ITD value, the current frame based on the previous ITD value to obtain a bitstream; and storing or transmitting the bitstream.

2 . The method of claim 1 , further comprising:
incrementing the frame count by one to obtain a current frame count value, wherein the frame count counts a quantity of continuous target frames, and wherein a target frame uses an ITD value of a previous frame of the target frame as an ITD value of the target frame; and comparing the current frame count value with a maximum quantity of the continuous target frames, wherein determining whether to use the previous ITD value as the current ITD value comprises determining, in response to the current frame count value not being greater than the maximum quantity, to use the previous ITD value as the current ITD value.

3 . The method of claim 2 , wherein determining whether to use the previous ITD value as the current ITD value further comprises determining to use the previous ITD value as the current ITD value when the signal-to-noise ratio satisfies a preset signal-to-noise ratio condition and the current frame count value is not greater than the maximum quantity.

4 . An encoder, comprising:
a memory configured to store instructions; and a processor coupled to the memory and configured to execute the instructions to cause the encoder to:
obtain a signal-to-noise ratio of a current frame;
determine whether the signal-to-noise ratio meets one of a plurality of preset conditions;
adjust, in response to determining that the signal-to-noise ratio meets the one of the preset conditions, a frame count to obtain an adjusted frame count;
determine, based on the adjusted frame count, whether to use a previous inter-channel time difference (ITD) value of a previous frame of the current frame as a current ITD value of the current frame;
encode, in response to determining to use the previous ITD value as the current ITD value, the current frame based on the previous ITD value to obtain a bitstream; and
store or transmit the bitstream.

5 . The encoder of claim 4 , wherein the processor is further configured to execute the instructions to cause the encoder to:
increment the frame count by one to obtain a current frame count value, wherein the frame count counts a quantity of continuous target frames, and wherein a target frame uses an ITD value of a previous frame of the target frame as an ITD value of the target frame; compare the current frame count value with a maximum quantity of the continuous target frames; and determine, in response to the current frame count value not being greater than the maximum quantity, to use the previous ITD value as the current ITD value.

6 . The encoder of claim 5 , wherein the processor is further configured to execute the instructions to cause the encoder to further determine to use the previous ITD value as the current ITD value when the signal-to-noise ratio satisfies a preset signal-to-noise ratio condition and the current frame count value is not greater than the maximum quantity.

7 . A computer program product comprising computer-executable instructions that are stored on a non-transitory computer-readable storage medium and that, when executed by a processor, cause an encoder to:
obtain a signal-to-noise ratio of a current frame; determine whether the signal-to-noise ratio meets one of a plurality of preset conditions; adjust, in response to determining that the signal-to-noise ratio meets the one of the preset conditions, a frame count to obtain an adjusted frame count; determine, based on the adjusted frame count, whether to use a previous inter-channel time difference (ITD) value of a previous frame of the current frame as a current ITD value of the current frame; encode, in response to determining to use the previous ITD value as the current ITD value, the current frame based on the previous ITD value to obtain a bitstream; and store or transmit the bitstream.

8 . The computer program product of claim 7 , wherein the computer-executable instructions, when executed by the processor, further cause the encoder to:
increment the frame count by one to obtain a current frame count value, wherein the frame count counts a quantity of continuous target frames, and wherein a target frame uses an ITD value of a previous frame of the target frame as an ITD value of the target frame; compare the current frame count value with a maximum quantity of the continuous target frames; and determine, in response to the current frame count value not being greater than the maximum quantity, to use the previous ITD value as the current ITD value.

9 . The computer program product of claim 8 , wherein the computer-executable instructions, when executed by the processor, further cause the encoder to further determine to use the previous ITD value as the current ITD value when the signal-to-noise ratio satisfies a preset signal-to-noise ratio condition and the current frame count value is not greater than the maximum quantity.

10 . The computer program product of claim 7 , wherein the signal-to-noise ratio comprises a subband signal-to-noise ratio.

11 . The computer program product of claim 7 , wherein the signal-to-noise ratio comprises a modified subband signal-to-noise ratio.

12 . The computer program product of claim 7 , wherein the signal-to-noise ratio comprises a segmental signal-to-noise ratio.

13 . The computer program product of claim 7 , wherein the signal-to-noise ratio comprises a modified segmental signal-to-noise ratio.

14 . The computer program product of claim 7 , wherein the signal-to-noise ratio comprises a full-band signal-to-noise ratio.

15 . The computer program product of claim 7 , wherein the signal-to-noise ratio comprises a modified full-band signal-to-noise ratio.

16 . The method of claim 1 , wherein the signal-to-noise ratio comprises a subband signal-to-noise ratio.

17 . The method of claim 1 , wherein the signal-to-noise ratio comprises a modified subband signal-to-noise ratio.

18 . The method of claim 1 , wherein the signal-to-noise ratio comprises a segmental signal-to-noise ratio.

19 . The method of claim 1 , wherein the signal-to-noise ratio comprises a modified segmental signal-to-noise ratio.

20 . The method of claim 1 , further comprising obtaining a multi-channel signal of the current frame, wherein the multi-channel signal includes a first-channel signal and a second-channel signal.

Assignees

• Huawei Tech Co Ltd

Inventors

• Li Haiting
• Liu Zexin
• Zhang Xingtao
• Miao Lei

Classifications

• H04S2420/03

  Application of parametric coding in stereophonic audio systems · CPC title

• H04S3/00

  Systems employing more than two channels, e.g. quadraphonic (H04S5/00, H04S7/00 take precedence) · CPC title

• G10L25/06

  the extracted parameters being correlation coefficients · CPC title

• G10L19/0204

  using subband decomposition · CPC title

• G10L19/008 Primary

  Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing · CPC title