US 2012/0232912 A1 · Method, Apparatus and Computer Program Product for Audio Coding

Abstract

The invention relates to a method and an apparatus in which samples of at least a part of an audio signal of a first channel and a part of an audio signal of a second channel are used to estimate a time delay between said part of the audio signal of said first channel and said part of the audio signal of said second channel. The method includes windowing the samples; performing a time-to-frequency domain transform; and determining an inter-channel time delay between said part of the audio signal of the first channel and said part of the audio signal of said second channel on the basis of the frequency domain representations. There is also disclosed a method and an apparatus for decoding the encoded samples.

Claims58

Dependent claims

A method comprising

using samples of at least a part of an audio signal of a first channel and a part of an audio signal of a second channel to estimate a time delay between said part of the audio signal of said first channel and said part of the audio signal of said second channel;
windowing the samples of said first channel and said second channel by a window function to form an analysis frame of said first channel and an analysis frame of said second channel;
performing a time-to-frequency domain transform on the analysis frames to form a frequency domain representation of said part of the audio signal of said first channel and said part of the audio signal of said second channel;
and
determining an inter-channel time delay between said part of the audio signal of the first channel and said part of the audio signal of said second channel on the basis of the frequency domain representations.

2 more elements

A method comprising

receiving an encoded audio signal of a first channel and an encoded audio signal of a second channel;
receiving an indication of an inter-channel time delay between said encoded audio signal of the first channel and said encoded audio signal of the second channel;
decoding said encoded audio signal of the first channel and said encoded audio signal of the second channel to form decoded samples of the audio signal of the first channel and the audio signal of the second channel;
performing a time-to-frequency domain transform on the windowed samples to form a frequency domain representation of said audio signal of said first channel and said audio signal of said second channel;
shifting the frequency domain representation of one of said audio signal of said first channel and said audio signal of said second channel on the basis of said indication;
performing a frequency-to-time domain transform on the frequency domain representation of said audio signal of said first channel and said audio signal of said second channel to form decoded samples of the audio signal of the first channel and of the audio signal of the second channel;
and
windowing said decoded samples of said first channel and said second channel by a window function to form a synthesized audio signal of the first channel and a synthesized audio signal of the second channel.

5 more elements

An apparatus comprising

means for using samples of at least a part of an audio signal of a first channel and a part of an audio signal of a second channel to estimate a time delay between said part of the audio signal of said first channel and said part of the audio signal of said second channel;
means for windowing the samples of said first channel and said second channel by a window function to form an analysis frame of said first channel and an analysis frame of said second channel;
means for performing a time-to-frequency domain transform on the analysis frames to form a frequency domain representation of said part of the audio signal of said first channel and said part of the audio signal of said second channel;
and
means for determining an inter-channel time delay between said part of the audio signal of the first channel and said part of the audio signal of said second channel on the basis of the frequency domain representations.