US 7,853,022 B2 · Audio spatial environment engine

Abstract

An audio spatial environment engine for flexible and scalable up-mixing from an M channel audio system to an N channel audio system, where M and N are integers and N is greater than M, is provided. The input M channel audio is provided to an analysis filter bank which converts the time domain signals into frequency domain signals. Relevant inter-channel spatial cues are extracted from the frequency domain signals on a sub-band basis and are used as parameters to generate adaptive N channel filters which control the spatial placement of a frequency band element in the up-mixed sound field. The N channel filters are smoothed across both time and frequency to limit filter variability which could cause annoying fluctuation effects. The smoothed N channel filters are then applied to adaptive combinations of the frequency domain input signals and are provided to a synthesis filter bank which generates the N channel time domain output signals.

Claims21

Dependent claims

A system for converting between an N channel audio system and an M channel audio system, where M and N are integers and N is greater than M, comprising:

a reference down-mixer receiving one or more of N channels of audio data and converting the one or more N channels of audio data to one or more M channels of audio data;
a reference up-mixer receiving the one or more M channels of audio data and converting the one or more M channels of audio data to one or more N′ channels of audio data;
a receiver receiving one or more corrected M channels of audio data and converting the one or more corrected M channels of audio data to one or more N′ channels of audio data;
and
a correction system receiving the one or more M channels of audio data, the one or more N channels of audio data, and the one or more N′ channels of audio data and correcting the one or more M channels of audio data based on differences between the one or more N channels of audio data and the one or more N′ channels of audio data.

2 more elements

A system for converting between an N channel audio system and an M channel audio system, where M and N are integers and N is greater than M, comprising:

a reference down-mixer receiving one or more of N channels of audio data and converting the one or more N channels of audio data to one or more M channels of audio data;
a correction system receiving the one or more M channels of audio data, the one or more N channels of audio data, and one or more N′ channels of audio data and correcting the one or more M channels of audio data based on differences between the one or more N channels of audio data and the one or more N′ channels of audio data;
and
a receiver receiving the corrected one or more M channels of audio data and generating one or more N″ channels of audio data.

1 more element

Dependencies are inferred from the claim text.

Audio spatial environment engine

Life of this patent

Audio spatial environment engine

Life of this patent

Abstract

Claims21