Stereo audio signal delay estimation method and apparatus

An apparatus, comprising:

• a memory configured to store instructions;
• and
• a processor coupled to the memory and configured to execute the instructions to cause the apparatus to:
• obtain a current frame of a stereo audio signal, wherein the current frame comprises a first channel audio signal, a second channel audio signal, and a noise signal;
• and
• estimate an inter-channel time difference between the first channel audio signal and the second channel audio signal using a first algorithm when a first signal type of the noise signal is a coherent noise signal type, or using a second algorithm when the first signal type is a diffuse noise signal type,
• wherein the first algorithm comprises weighting a frequency domain cross power spectrum of the current frame based on a first weighting function comprising a first construction factor, and wherein the second algorithm comprises weighting the frequency domain cross power spectrum based on a second weighting function comprising a second construction factor different from the first construction factor, and wherein executing the instructions to cause the apparatus to estimate the inter-channel time difference using the first algorithm further causes the apparatus to:
• obtain a first channel frequency domain signal and a second channel frequency domain signal;
• calculate the frequency domain cross power spectrum based on the first channel frequency domain signal and the second channel frequency domain signal;
• weight the frequency domain cross power spectrum based on the first weighting function to obtain a weighted frequency domain cross power spectrum;
• and
• obtain a first estimated value of the inter-channel time difference based on the weighted frequency domain cross power spectrum, and
• wherein the first construction factor comprises:
• a first Wiener gain factor corresponding to the first channel frequency domain signal, a second Wiener gain factor corresponding to the second channel frequency domain signal, an amplitude weighting parameter, and a squared coherence value of the current frame.

A computer program product comprising computer-executable instructions stored on a non-transitory computer-readable storage medium, the computer-executable instructions when executed by a processor of an apparatus, cause the apparatus to:

• obtain a current frame of a stereo audio signal, wherein the current frame comprises a first channel audio signal, a second channel audio signal, and a noise signal;
• and
• estimate an inter-channel time difference between the first channel audio signal and the second channel audio signal using one of a first algorithm when a first signal type of the noise signal is a coherent noise signal type, wherein the first algorithm comprises weighting a frequency domain cross power spectrum of the current frame based on a first weighting function comprising a first construction factor, or a second algorithm when the first signal type of the noise signal is a diffuse noise signal type, wherein the second algorithm comprises weighting the frequency domain cross power spectrum of the current frame based on a second weighting function comprising a second construction factor different from the first construction factor;
• and
• wherein the computer-executable instructions to estimate the inter-channel time difference using the first algorithm when executed by the processor, further cause the apparatus to:
• obtain a first channel frequency domain signal and a second channel frequency domain signal;
• calculate the frequency domain cross power spectrum based on the first channel frequency domain signal and the second channel frequency domain signal;
• weight the frequency domain cross power spectrum based on the first weighting function to obtain a weighted frequency domain cross power spectrum;
• and
• obtain a first estimated value of the inter-channel time difference based on the weighted frequency domain cross power spectrum, and
• wherein the first construction factor comprises:
• a first Wiener gain factor corresponding to the first channel frequency domain signal, a second Wiener gain factor corresponding to the second channel frequency domain signal, an amplitude weighting parameter, and a squared coherence value of the current frame.