Spatial audio analysis and synthesis for binaural reproduction and format conversion
AssigneeCreative Technology Ltd
InventorsMichael M. Goodwin, Jean-Marc Jot, Mark Dolson
Life of this patent
Estimating the term…
Abstract
A frequency-domain method for format conversion or reproduction of 2-channel or multi-channel audio signals such as recordings is described. The reproduction is based on spatial analysis of directional cues in the input audio signal and conversion of these cues into audio output signal cues for two or more channels in the frequency domain.
Claims12
A method of generating an audio output signal having at least first and second audio output channels from a time-frequency signal representation of an audio input signal having at least one audio input channel and at least one spatial information input channel, comprising:
- selecting a spatial audio output format such that a direction in the audio output signal is characterized by at least one of an inter-channel amplitude difference and an inter-channel phase difference at each frequency between the at least first and second audio output channels;
- receiving directional information corresponding to each of a plurality of frames of the time-frequency signal representation, wherein directional information is derived by decomposing the audio input signal into primary and ambient components and performing a spatial analysis on at least a time-frequency representation of the primary components;
- and
- generating first and second frequency domain output signals from the directional information and the time-frequency signal representation that, at each time and frequency, have inter-channel amplitude and phase differences between the at least first and second audio output channels that characterize a direction in the spatial audio output format.
A method of generating an audio output signal having at least first and second audio output channels from a time-frequency signal representation of an audio input signal having at least one audio input channel and at least one spatial information input channel, comprising:
- selecting a spatial audio output format such that a direction in the audio output signal is characterized by at least one of an inter-channel amplitude difference and an inter-channel phase difference at each frequency between the at least first and second audio output channels;
- receiving an ambient directional vector corresponding to at least one ambient component of the audio input signal, receiving a time-frequency representation of ambient components corresponding to the audio input signal, and using the ambient directional vector and ambient components to generate the first and second frequency domain output signals that, at each time and frequency, have inter-channel amplitude and phase differences between the at least first and second audio output channels that characterize a direction in the spatial audio output format.
A method of generating a binaural audio signal, comprising:
- converting an input audio signal to a frequency domain representation;
- decomposing the input audio signal into primary and ambient components and performing a spatial analysis on at least a time frequency representation of the primary components to derive a directional vector having direction angle information, the directional vector corresponding to the localization direction of each of a plurality of time frequency components from the frequency domain representation;
- generating first and second frequency domain signals from the frequency domain representation that, at each time and frequency, have inter-channel amplitude and phase differences that characterize a direction that corresponds to the directional vector;
- and
- performing an inverse transform to convert the frequency domain signals.
Dependencies are inferred from the claim text.