Multichannel spectral vector mapping audio apparatus and method

A method of reproducing on a second set of channels an audio signal present on a first set of channels, comprising:

• providing said audio signal organized into successive temporal aperture periods in digital format on said first set of channels along with a set of digitally formatted mapping coefficients for each of aperture periods that vary among said aperture periods, and that, for each channel in said first set, map the audio signal level of said channel onto respective channels of said second set of channels, reading said audio signal on said first set of channels and said coefficients, and applying said coefficients to said audio signal on said first set of channels to obtain the audio signal on said second set of channels, wherein the mapping coefficients for each of said first set of channels are stored on said digital medium as respective vectors that allocate a distribution of at least a portion of the signal on said channel among the channels of said second set, said coefficients are read from said digital medium in the form of said vectors, and the coefficients that are applied to said audio signal on said first set of channels to obtain the audio signal on said second set of channels are derived from said vectors.

An audio signal conditioning circuit for conditioning an audio signal on a first set of channels to be configured onto a second set of channels, comprising:

• a mapping coefficient generating circuit that, for each channel in said first set, establishes mapping coefficients in the form of digitally encoded signals for each of aperture periods that vary among said aperture periods, and that map audio signal levels on said channel onto desired signal levels for each channel in said second set, and a transfer circuit connected to apply said audio signal organized into successive temporal aperture periods on said first set of channels along with said mapping coefficient signals to a digital medium, wherein said coefficient generating circuit generates the coefficients for each of said first set of channels as a vector that allocates a distribution of at least a portion of the signal on said first set channel among the channels of the second set.

A circuit for reproducing on a second set of channels an audio signal present on a first set of channels, comprising:

• a receive circuit connected to read said audio signal organized into successive temporal aperture periods on said first set of channels along with a set of mapping coefficients for each of aperture periods that vary among said aperture periods, and that, for each channel in said first set, map the audio signal level of said channel onto respective channels of said second set of channels, and a decoding circuit connected to apply said coefficients to said audio signal on said first set of channels to obtain the audio signal on said second set of channels, wherein, for coefficients for said first set of channels that are provided in the form of respective vectors that allocate a distribution of at least a portion of the signal on said channel among the channels of said second set, said receive circuit is connected to read said coefficients in the form of said vectors, and said decoding circuit derives said coefficients from said vectors for application to said audio signal on said first set of channels.

An audio signal conditioning circuit for conditioning an audio signal on monaural or stereo source channels to be reconfigured into a multi-channel format having at least two target channels, comprising:

• a spectral decomposition circuit connected to divide the signal organized into successive temporal aperture periods on each source channel into multiple spectral bands, and a spectral mapping coefficient (SMC) generating circuit that, for each band of each source channel, establishes SMCs for each of aperture periods that vary among said aperture periods, and that map the signal level within said band onto desired signal levels for a corresponding spectral band of each target channel, wherein said SMC generating circuit generates the SMCs for each source channel as a vector that allocates a distribution of at least a portion of the audio signal on said source channel among said target channels.

A method of allocating an audio signal among a plurality of output channels, comprising:

• providing an audio signal organized into successive temporal aperture periods, providing a vector signal that defines a spatial vector, establishing a correspondence between different vectors and different allocations of said audio signal among a plurality of output channels, determining the allocation that corresponds to the vector defined by said vector signal, and allocating said audio signal among said output channels based upon the allocation thus determined, wherein said correspondence is established by establishing different sets of coefficients for different vectors, and said coefficients for each of aperture periods vary among said aperture periods.

A method of encoding an audio signal for allocation among a plurality of output channels, comprising:

• generating vector signals that define different spatial vectors corresponding to different allocations of said audio signal organized into successive temporal aperture periods among said channels, and applying said audio signal along with said vector signals in digital format to a digital medium, wherein different sets of coefficients for said different spatial vectors are established and said coefficients for each of aperture periods vary among said aperture periods.

An encoded non-transitory digital audio medium, comprising:

• a digital audio storage medium have a first set of digital signal channels, a digitally encoded audio signal stored on said first set of channels and organized into successive temporal aperture periods, and for each channel in said first set, a set of mapping coefficients for each of said aperture periods stored on said medium in the form of digitally encoded signals that vary among said aperture periods and map audio signal levels on said channel onto desired signal levels for each channel in a second channel set, wherein the mapping coefficients for each of said first set of channels at any given time define a vector that allocates a distribution of at least a portion of the signal on said channel among the channels of the second set.