Audio signal processing method and device

• US 9,848,275 B2
• Filed: 04/02/2015
• Issued: 12/19/2017
• Est. Priority Date: 04/02/2014
• Status: Active Grant

• Current Assignee: GCOA Company Limited, WILUS Inc.
• Original Assignee: WILUS Inc.
• Inventors: Lee, Taegyu, Oh, Hyun Oh
• Primary Examiner(s): HUBER, PAUL W
• Application Number:
  US15/300,273
• Publication Number:
  US 20170188174A1
• Time in Patent Office: 992 Days
• Field of Search: None
• CPC Class Codes: G10L 19/008 Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes
• CPC Class Codes: H04R 2430/03 Synergistic effects of band splitting and sub-band processing
• CPC Class Codes: H04R 2499/11 Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's
• CPC Class Codes: H04R 2499/15 Transducers incorporated in visual displaying devices, e.g. televisions, computer displays, laptops
• CPC Class Codes: H04R 3/04 for correcting frequency response
• CPC Class Codes: H04S 2400/01 Multi-channel, i.e. more than two input channels, sound reproduction with two speakers wherein the multi-channel information is substantially preserved
• CPC Class Codes: H04S 2400/03 Aspects of down-mixing multi-channel audio to configurations with lower numbers of playback channels, e.g. 7.1 -> 5.1 H04S2400/01 takes precedence
• CPC Class Codes: H04S 2400/11 Positioning of individual sound objects, e.g. moving airplane, within a sound field H04S2420/13 takes precedence
• CPC Class Codes: H04S 2420/01 Enhancing the perception of the sound image or of the spatial distribution using head related transfer functions [HRTF's] or equivalents thereof, e.g. interaural time difference [ITD] or interaural level difference [ILD]
• CPC Class Codes: H04S 2420/07 Synergistic effects of band splitting and sub-band processing
• CPC Class Codes: H04S 3/008 in which the audio signals are in digital form, i.e. employing more than two discrete digital channels data reduction aspects thereof based on psychoacoustics G10L19/02
• CPC Class Codes: H04S 7/303 Tracking of listener position or orientation
• CPC Class Codes: H04S 7/306 For headphones
• CPC Class Codes: H04S 7/307 Frequency adjustment, e.g. tone control H04S7/301 takes precedence

Abstract

The present invention relates to a method and an apparatus for processing an audio signal, and more particularly, to a method and an apparatus for processing an audio signal, which synthesizes an object signal and a channel signal and effectively binaural-render the synthesized signal.

To this end, the present invention provides a method for processing an audio signal, including: receiving an input audio signal including at least one of a multi-channel signal and a multi-object signal; receiving type information of a filter set for binaural filtering of the input audio signal, the type of the filter set being one of a finite impulse response (FIR) filter, a parameterized filter in a frequency domain, and a parameterized filter in a time domain; receiving filter information for binaural filtering based on the type information; and performing the binaural filtering for the input audio signal by using the received filter information, wherein when the type information indicates the parameterized filter in the frequency domain, in the receiving of the filter information, a subband filter coefficient having a length determined for each subband of a frequency domain is received, and in the performing of the binaural filtering, each subband signal of the input audio signal is filtered by using the subband filter coefficient corresponding thereto and an apparatus for processing an audio signal by using the same.

Claims

1. A method for processing an audio signal, the method comprising:

receiving an input audio signal including at least one of a multi-channel signal and a multi-object signal;

receiving type information of a filter set for binaural filtering of the input audio signal, the type of the filter set being one of a finite impulse response (FIR) filter, a parameterized filter in a frequency domain, and a parameterized filter in a time domain;

receiving filter information for binaural filtering based on the type information; and

performing the binaural filtering for the input audio signal by using the received filter information,

wherein when the type information indicates the parameterized filter in the frequency domain,

the receiving filter information step receives subband filter coefficients having a length determined for each subband of a frequency domain, and

the performing the binaural filtering step filters each subband signal of the input audio signal by using the subband filter coefficients corresponding thereto.

2. The method of claim 1, wherein the length of each subband filter coefficients is determined based on reverberation time information of the corresponding subband, which is obtained from proto-type filter coefficients, and

the length of at least one subband filter coefficients obtained from the same proto-type filter coefficients is different from the length of another subband filter coefficients.

3. The method of claim 1, further comprising:

when the type information indicates the parameterized filter in the frequency domain,

receiving information on the number of frequency bands to perform the binaural rendering and information on the number of frequency bands to perform convolution;

receiving a parameter for performing tap-delay line filtering with respect to each subband signal of a high-frequency subband group having a frequency band to perform the convolution as a boundary; and

performing the tap-delay line filtering for each subband signal of the high-frequency group by using the received parameter.

4. The method of claim 3, wherein the number of subbands of the high-frequency subband group performing the tap-delay line filtering is determined based on a difference between the number of frequency bands to perform the binaural rendering and the number of frequency bands to perform the convolution.

5. The method of claim 3, wherein the parameter includes delay information extracted from the subband filter coefficients corresponding to each subband signal of the high-frequency group and gain information corresponding to the delay information.

6. The method of claim 1, wherein when the type information indicates the FIR filter, the receiving the filter information step receives the proto-type filter coefficients corresponding to each subband signal of the input audio signal.

7. An apparatus for processing an audio signal for performing binaural rendering of an input audio signal including at least one of a multi-channel signal and a multi-object signal, wherein the apparatus for processing an audio signal is configured to:

receive type information of a filter set for binaural filtering of the input audio signal, the type of the filter set being one of a finite impulse response (FIR) filter, a parameterized filter in a frequency domain, and a parameterized filter in a time domain,

receive filter information for binaural filtering based on the type information, and

perform the binaural filtering for the input audio signal by using the received filter information, and

wherein when the type information indicates the parameterized filter in the frequency domain,

the apparatus for processing an audio signal receives subband filter coefficients having a length determined for each subband of a frequency domain and filters each subband signal of the input audio signal by using the subband filter coefficients corresponding thereto.