Method and Apparatus for Determining Inter-Channel Time Difference Parameter

Patent metadata

Field	Value
Publication number	US-2017372710-A1
Application number	US-201715698107-A
Country	US
Kind code	A1
Filing date	Sep 7, 2017
Priority date	Mar 9, 2015
Publication date	Dec 28, 2017
Grant date	—

Abstract

A method for determining an inter-channel time difference (ITD) parameter includes determining a reference parameter according to a time-domain signal on a first sound channel and a time-domain signal on a second sound channel, where the reference parameter corresponds to a sequence of obtaining the time-domain signal on the first sound channel and the time-domain signal on the second sound channel, determining a search range according to the reference parameter and a limiting value (T max ), where the T max is determined according to a sampling rate of the time-domain signal on the first sound channel, and performing search processing within the search range based on a frequency-domain signal on the first sound channel and a frequency-domain signal on the second sound channel to determine a first ITD parameter corresponding to the first sound channel and the second sound channel.

First claim

What is claimed is:

1 . A method for determining an inter-channel time difference (ITD) parameter, comprising:
determining a reference parameter according to a time-domain signal on a first sound channel and a time-domain signal on a second sound channel, wherein the reference parameter corresponds to a sequence of obtaining the time-domain signal on the first sound channel and the time-domain signal on the second sound channel, and wherein the time-domain signal on the first sound channel and the time-domain signal on the second sound channel correspond to a first time period; determining a search range according to the reference parameter and a limiting value (T max ), wherein the T max is determined according to a sampling rate of the time-domain signal on the first sound channel, and wherein the search range either falls within [−T max , 0] or falls within [0, T max ]; and performing search processing within the search range based on a frequency-domain signal on the first sound channel and a frequency-domain signal on the second sound channel to determine a first ITD parameter corresponding to the first sound channel and the second sound channel.

2 . The method according to claim 1 , wherein determining the reference parameter comprises:
performing cross-correlation processing on the time-domain signal on the first sound channel and the time-domain signal on the second sound channel to determine a first cross-correlation processing value and a second cross-correlation processing value, wherein the first cross-correlation processing value is a maximum function value, within a preset range, of a cross-correlation function of the time-domain signal on the first sound channel relative to the time-domain signal on the second sound channel, and wherein the second cross-correlation processing value is a maximum function value, within the preset range, of a cross-correlation function of the time-domain signal on the second sound channel relative to the time-domain signal on the first sound channel; and determining the reference parameter according to a value relationship between the first cross-correlation processing value and the second cross-correlation processing value.

3 . The method according to claim 2 , wherein the reference parameter is an index value corresponding to a larger one of the first cross-correlation processing value and the second cross-correlation processing value.

4 . The method according to claim 2 , wherein the reference parameter is an opposite number of an index value corresponding to a larger one of the first cross-correlation processing value and the second cross-correlation processing value.

5 . The method according to claim 1 , wherein determining the reference parameter comprises:
performing peak detection processing on the time-domain signal on the first sound channel and the time-domain signal on the second sound channel to determine a first index value and a second index value, wherein the first index value corresponds to a maximum amplitude value of the time-domain signal on the first sound channel within a preset range, and wherein the second index value corresponds to a maximum amplitude value of the time-domain signal on the second sound channel within the preset range; and determining the reference parameter according to a value relationship between the first index value and the second index value.

6 . The method according to claim 1 , further comprising performing smoothing processing on the first ITD parameter based on a second ITD parameter, wherein the second ITD parameter is a smoothed value of an ITD parameter in a second time period, and wherein the second time period is before the first time period.

7 . The method according to claim 1 , wherein the search range is [T max /2, T max ], [0, T max /2], [−T max , −T max /2], or [−T max /2, 0].

8 . An apparatus for determining an inter-channel time difference (ITD) parameter, comprising:
a memory comprising instructions; and a processor coupled to the memory, wherein the instructions cause the processor to be configured to:
determine a reference parameter according to a time-domain signal on a first sound channel and a time-domain signal on a second sound channel, wherein the reference parameter corresponds to a sequence of obtaining the time-domain signal on the first sound channel and the time-domain signal on the second sound channel, and wherein the time-domain signal on the first sound channel and the time-domain signal on the second sound channel correspond to a first time period;
determine a search range according to the reference parameter and a limiting value (T max ), wherein the T max is determined according to a sampling rate of the time-domain signal on the first sound channel, and wherein the search range either falls within [−T max , 0] or falls within [0, T max ]; and
perform search processing within the search range based on a frequency-domain signal on the first sound channel and a frequency-domain signal on the second sound channel to determine a first ITD parameter corresponding to the first sound channel and the second sound channel.

9 . The apparatus according to claim 8 , wherein the instructions further cause the processor to be configured to:
perform cross-correlation processing on the time-domain signal on the first sound channel and the time-domain signal on the second sound channel to determine a first cross-correlation processing value and a second cross-correlation processing value; and determine the reference parameter according to a value relationship between the first cross-correlation processing value and the second cross-correlation processing value, wherein the first cross-correlation processing value is a maximum function value, within a preset range, of a cross-correlation function of the time-domain signal on the first sound channel relative to the time-domain signal on the second sound channel, and wherein the second cross-correlation processing value is a maximum function value, within the preset range, of a cross-correlation function of the time-domain signal on the second sound channel relative to the time-domain signal on the first sound channel.

10 . The apparatus according to claim 9 , wherein the reference parameter is an index value corresponding to a larger one of the first cross-correlation processing value and the second cross-correlation processing value.

11 . The apparatus according to claim 9 , wherein the reference parameter is an opposite number of an index value corresponding to a larger one of the first cross-correlation processing value and the second cross-correlation processing value.

12 . The apparatus according to claim 8 , wherein the instructions further cause the processor to be configured to:
perform peak detection processing on the time-domain signal on the first sound channel and the time-domain signal on the second sound channel to determine a first index value and a second index value; and determine the reference parameter according to a value relationship between the first index value and the second index value, wherein the first index value corresponds to a maximum amplitude value of the time-domain signal on the first sound channel within a preset range, and wherein the second index value corresponds to a maximum amplitude value of the time-domain signal on the second sound channel within the preset range.

13 . The apparatus according to claim 8 , wherein the instructions further cause the processor to be configured to perform smoothing processing on the first ITD parameter based on a second ITD parameter, wherein the second ITD parameter is a smoothed val

Assignees

• Huawei Tech Co Ltd

Inventors

• Zhang Xingtao
• Miao Lei

Classifications

• 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

• G10L19/022

  Blocking, i.e. grouping of samples in time; Choice of analysis windows; Overlap factoring · CPC title

• H04S3/00

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

• G10L25/03

  characterised by the type of extracted parameters · CPC title

• G10L19/08 Primary

  Determination or coding of the excitation function; Determination or coding of the long-term prediction parameters · CPC title